Many different types of valves, the use of a very wide scope. Sometimes it is in the pipeline is the main equipment, from control; sometimes it is a secondary device, play a supporting role. If used improperly, we will have "run, run, drip, drain" phenomenon, light from the impact of production, in serious cases lead to accidents. Therefore, understanding and proper use of valves is a very important issue.
First, valve Categories
In the heating system, use the valve there are many. Such as gate valve, globe valve, ball valve, butterfly valve, check valve, safety valve, regulating valve, balance valve, self-balance valve and so on. Introduce them one by one below.
1.1 Gate
Also known as gate valve, gate valve, is widely used as a valve.
Working Principle: gate valve seat sealing surface with a high degree of sealing surface bright and clean, smooth, consistent and processed into a very fitting, tight sealing vice. Gate through the stem to the lower pressure, the formation of the media and on-off. Play it off line role.
Advantages: small fluid resistance; full when the sealing surface from erosion; can be two-way flow of media use, there is no direction; durable; not only suitable for small valves, and valve can be bigger.
Disadvantages: high big; hoist a long time; bulky; repair difficult; If it is large diameter valve, relatively easy manual operation.
According to the different valve stem and dark leveraged leveraged clear; gate structure according to different sub-parallel and wedge; have a single gate, the sub-双闸board. Heating projects, commonly prescribed under the single-wedge gate valve (Z41H-16C) and dark under a single gate valve wedge (Z45T-10), the former is installed in one side of the thermal station, which is loaded thermal stations in the secondary side. It is usually played two roles: as a master switch from the role; as an auxiliary equipment before and after the main equipment used for maintenance.
Valve installation, not to hand round the horizon in the following (flip), or make long-term retention medium in the valve cover, easy to stem erosion. Works in the heating, the valve was the main force of the valve. Now widely used as the butterfly valve, butterfly valve has been replaced.
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Monday, November 29, 2010
Use of emergency shut down valve should be noted that several issues
Emergency shut down valve is developed in recent years, new products. In engineering applications is increasing. In the installation and commissioning process, we also found some problems, there are some problems in construction, some design problems. A good product not only better the quality of the product itself, the most important thing is to make sure it should be familiar with it, reasonably use it to play its greatest role.
First, why should we use the emergency shut down valve
As we all know, has always been the fire control network and life are two water supply systems, water supply by the two pumps, respectively, from the pumping station to the building for a long distance from the water supply pipe Rd. Road due to the laying of this pipeline construction workload larger double pipe materials, as well as to identify the maintenance of a pipeline has a lot of inconvenience; the second, fire pipeline for many years not to use, easy to rust, wall panels and interface due to corrosion thinning, usually do not have no pressure, and in case of fire, a sudden pressure increase in tube, easy to burst, resulting in water supply systems can not fire. Third, the promotion of water directly from the Shanghai municipal pumping pipe network is no longer underground pool. This will not only save the cost of the construction of the pool, while avoiding secondary pollution of the water. To maintain the water clean, and ensure people's health this is the most important one. Because of the advantages of these areas, so the product is gradually welcomed by everyone.
Second, emergency shut down valve working principle
Emergency closure of the hydraulic control valve is a valve. By the main valve, throttle, guided valve, pressure gauge, as well as take over the other tube components. When the main valve inlet pressure below the set pressure valve guide, the guide in a valve open state at this time, the main valve cavity pressure above the main valve outlet pressure equal to the existence of import and export pressure, flow through the outflow valve port export . When the fire pump start-up or increased pump pressure, more than I. valve set pressure, the main valve by the import wizard increased pressure valve control, the role of pressure in the spring increases, pressed down, driven spool Down to guide valve closed at this time the main valve inlet pressure constantly replenished through the throttle valve to the main valve cavity covered, due to valve downward pressure by the upward thrust is greater than, the main valve to close. Please note the key point is that the inlet pressure is less than set pressure of the valve has been turned on, set the inlet pressure is greater than the pressure, the valve remained closed. Many designers now have the misconception that as long as the emergency shutdown valve installed, it will be related, do not say what conditions, it is wrong.
Third, problems in project
The actual installation and commissioning, we encountered many unreasonable, put forward for discussion. Yu Shan Road, Shanghai Pudong is located in a residential area. The pump room is located at the ground floor of a residential area, 3-storey 12-storey and two eight-storey, layer 2.8 meters high, fire pump pump life are DN80, living 53 meters lift pump, fire pump head of 60 m, flow rate 10L / S , water supply sub-Rd, DN80 pipe into the roof tank. At the same time, the water pump from DN80 Rd DN80 for water pipes, so water pressure is not high, only reluctantly entered the tank. Emergency shut down valves to the pressure set at 0.5MPa, Rd for water at the same time, the pressure no more than 0.5MPa, pay only for water tanks. However, if there are four full tanks, tanks on the surface control valve to close, leaving only a water tank still dissatisfied with pay, the pressure will increase at this time, more than 0.5MPa, emergency shut down valve will be shut down, The remaining tanks will not be able to pay the. In order to smoothly every tank pay, on the need to stabilize the pressure of 0.45MPa, so that less than 0.5MPa, it will not lead to the closure. This requires an additional pump in the life of a pressure relief valve. Most units have no life pump pressure relief valve. Some units use the electric contact pressure gauge, when the water automatically when hypertension tripping over 0.5MPa, water pumps stop running, it still will not solve the problem of a single tank of pay.
The second issue is when the fire pump start-up, all the emergency shut down valves are open. DN80 Rd DN80 pumps at the water pipes, water tank at this time if not satisfied, do not pressure on, it is impossible for more than 0.5MPa, until the pool filled, liquid level control valve closed, pressure can be increased. Here the designer should consider increasing the capacity of pumps, or water pipe diameter decreases, the difference between the two should be at least second gear, such as water pump replaced DN100, replaced water pipes Rd DN65, the pressure at this time to more than 0.5MPa, since to the closure of the role of fire in order to send water to the building. A further example, in Shanghai there are a控江讲residential quarters DN100 fire pumps, water pipes Road DN80, still can not shut down, so multi-channel pumps and water pipes should be appropriate for the difference between two files.
The third problem is that the drainage pumping systems, pressure relief valve should discharge water into the fire pond or drainage should not be prescribed in a small ditch. Or give examples on the above, when in debug Rd pipes, all the way to gradually shut down all the way, the results of pumping water out of China by the pressure relief valve on the basement, drainage pump is far less than the fire pump, the results of the underground pumping station flooded. The best option is the life of pumps and fire pump use, water pressure testing at a constant flow from the impact. Quantitative pumps or pressure relief valve can also be added, but the pressure relief valve necessary in conjunction with the pool water pipes or sewer, sewer inlet diameter than the first year to second gear. After an emergency shut down valve through the user's program is better. Network of fire and life should be to increase inter-network fouling off a valve to prevent return fire hose water pollution.
The fourth issue, the choice of installation location. So far, the majority of users to the location of emergency shut-off valve installed on the wells dumb. There is a user to set up an emergency shut down valve on the stairs, I think on a more reasonable under the stairs, easy to debug and maintenance. Wells should be as dumb on the maintenance of sufficient space, and some dumb well an area of only 40 × 60cm2, but more than 1 meter deep, space is too small maintenance staff simply can not debug. And there is no expansion joints at both ends of the valve or soft joints, if required can not be removed搭下去maintenance. Area of the proposed wells dumb 60 × 80cm2, the depth should not be too deep to stamp covers do not touch after the appropriate valves. In addition, the need to increase or soft joints bend valves have an access.
The fifth point is that before the opening of the pipeline should be in the running water. We found in the debugging process can not close the emergency shut-off valve, remove the pressure of factors, suspected of having little stones stay in the body memory, the check valve 12 the majority have little stones remaining, including two under the body cavity of filled. Therefore, the installation of emergency shut down valve should be cleaned before the pipeline, the valve in order to ensure that all work properly. valve ball valve gate valve check valve globe valve butterfly valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com
First, why should we use the emergency shut down valve
As we all know, has always been the fire control network and life are two water supply systems, water supply by the two pumps, respectively, from the pumping station to the building for a long distance from the water supply pipe Rd. Road due to the laying of this pipeline construction workload larger double pipe materials, as well as to identify the maintenance of a pipeline has a lot of inconvenience; the second, fire pipeline for many years not to use, easy to rust, wall panels and interface due to corrosion thinning, usually do not have no pressure, and in case of fire, a sudden pressure increase in tube, easy to burst, resulting in water supply systems can not fire. Third, the promotion of water directly from the Shanghai municipal pumping pipe network is no longer underground pool. This will not only save the cost of the construction of the pool, while avoiding secondary pollution of the water. To maintain the water clean, and ensure people's health this is the most important one. Because of the advantages of these areas, so the product is gradually welcomed by everyone.
Second, emergency shut down valve working principle
Emergency closure of the hydraulic control valve is a valve. By the main valve, throttle, guided valve, pressure gauge, as well as take over the other tube components. When the main valve inlet pressure below the set pressure valve guide, the guide in a valve open state at this time, the main valve cavity pressure above the main valve outlet pressure equal to the existence of import and export pressure, flow through the outflow valve port export . When the fire pump start-up or increased pump pressure, more than I. valve set pressure, the main valve by the import wizard increased pressure valve control, the role of pressure in the spring increases, pressed down, driven spool Down to guide valve closed at this time the main valve inlet pressure constantly replenished through the throttle valve to the main valve cavity covered, due to valve downward pressure by the upward thrust is greater than, the main valve to close. Please note the key point is that the inlet pressure is less than set pressure of the valve has been turned on, set the inlet pressure is greater than the pressure, the valve remained closed. Many designers now have the misconception that as long as the emergency shutdown valve installed, it will be related, do not say what conditions, it is wrong.
Third, problems in project
The actual installation and commissioning, we encountered many unreasonable, put forward for discussion. Yu Shan Road, Shanghai Pudong is located in a residential area. The pump room is located at the ground floor of a residential area, 3-storey 12-storey and two eight-storey, layer 2.8 meters high, fire pump pump life are DN80, living 53 meters lift pump, fire pump head of 60 m, flow rate 10L / S , water supply sub-Rd, DN80 pipe into the roof tank. At the same time, the water pump from DN80 Rd DN80 for water pipes, so water pressure is not high, only reluctantly entered the tank. Emergency shut down valves to the pressure set at 0.5MPa, Rd for water at the same time, the pressure no more than 0.5MPa, pay only for water tanks. However, if there are four full tanks, tanks on the surface control valve to close, leaving only a water tank still dissatisfied with pay, the pressure will increase at this time, more than 0.5MPa, emergency shut down valve will be shut down, The remaining tanks will not be able to pay the. In order to smoothly every tank pay, on the need to stabilize the pressure of 0.45MPa, so that less than 0.5MPa, it will not lead to the closure. This requires an additional pump in the life of a pressure relief valve. Most units have no life pump pressure relief valve. Some units use the electric contact pressure gauge, when the water automatically when hypertension tripping over 0.5MPa, water pumps stop running, it still will not solve the problem of a single tank of pay.
The second issue is when the fire pump start-up, all the emergency shut down valves are open. DN80 Rd DN80 pumps at the water pipes, water tank at this time if not satisfied, do not pressure on, it is impossible for more than 0.5MPa, until the pool filled, liquid level control valve closed, pressure can be increased. Here the designer should consider increasing the capacity of pumps, or water pipe diameter decreases, the difference between the two should be at least second gear, such as water pump replaced DN100, replaced water pipes Rd DN65, the pressure at this time to more than 0.5MPa, since to the closure of the role of fire in order to send water to the building. A further example, in Shanghai there are a控江讲residential quarters DN100 fire pumps, water pipes Road DN80, still can not shut down, so multi-channel pumps and water pipes should be appropriate for the difference between two files.
The third problem is that the drainage pumping systems, pressure relief valve should discharge water into the fire pond or drainage should not be prescribed in a small ditch. Or give examples on the above, when in debug Rd pipes, all the way to gradually shut down all the way, the results of pumping water out of China by the pressure relief valve on the basement, drainage pump is far less than the fire pump, the results of the underground pumping station flooded. The best option is the life of pumps and fire pump use, water pressure testing at a constant flow from the impact. Quantitative pumps or pressure relief valve can also be added, but the pressure relief valve necessary in conjunction with the pool water pipes or sewer, sewer inlet diameter than the first year to second gear. After an emergency shut down valve through the user's program is better. Network of fire and life should be to increase inter-network fouling off a valve to prevent return fire hose water pollution.
The fourth issue, the choice of installation location. So far, the majority of users to the location of emergency shut-off valve installed on the wells dumb. There is a user to set up an emergency shut down valve on the stairs, I think on a more reasonable under the stairs, easy to debug and maintenance. Wells should be as dumb on the maintenance of sufficient space, and some dumb well an area of only 40 × 60cm2, but more than 1 meter deep, space is too small maintenance staff simply can not debug. And there is no expansion joints at both ends of the valve or soft joints, if required can not be removed搭下去maintenance. Area of the proposed wells dumb 60 × 80cm2, the depth should not be too deep to stamp covers do not touch after the appropriate valves. In addition, the need to increase or soft joints bend valves have an access.
The fifth point is that before the opening of the pipeline should be in the running water. We found in the debugging process can not close the emergency shut-off valve, remove the pressure of factors, suspected of having little stones stay in the body memory, the check valve 12 the majority have little stones remaining, including two under the body cavity of filled. Therefore, the installation of emergency shut down valve should be cleaned before the pipeline, the valve in order to ensure that all work properly. valve ball valve gate valve check valve globe valve butterfly valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com
Dump Truck valve technology standards (b)
Table 1 allow the oil temperature range ℃
ABC level measurement
Allow the oil temperature range ± 1.0 ± 2.0 ± 5.0
5.2 Viscosity
At 50 ℃, the oil viscosity for the campaign 17 × l0-6 ~ 43 × 10-6m2 / s.
5.3 filtering accuracy
Oil filters shall not be less than the accuracy of 25μm.
5.4 Test apparatus, precision instruments
5.4.1 According to A, B, C grading of the three measurements to select the appropriate test instruments, meters, type testing should not be less than B-level measurement hierarchy, the factory test should not be less than C-level measurement hierarchy.
5.4.2 When charged with the value of parameter changes in the scope of the instructions in Table 2 provides the framework, it allows measurement of test parameters recorded.
Table 2 was charged with the parameters allowed to change the value of the scope of the instructions
ABC level measurement
Flow% ± 0.5 ± 1.5 ± 2.5
Pressure% ± 0.5 ± 1.5 ± 2.5
Temperature ℃ ± 1.0 ± 2.0 ± 5.0
Viscosity% ± 5 ± 10.0 ± 15
5.4.3 test test instruments, meters shall not exceed the measurement error of the provisions of Table 3.
Table 3 Instruments and Measurement tolerance
ABC level measurement
Flow% ± 0.5 ± 1.5 ± 2.5
Pressure% ± 0.5 ± 1.5 ± 2.5
Temperature ℃ ± 0.5 ± 1.0 ± 2.0
Note: given in Table 3 is chosen by the scope of the apparatus, instruments used in the actual scope of the range of the margin of error allowed.
5.4.4 the preparation of the test report should indicate the level of measurement tests.
6 Test device
6.1 Pressure point
6.1.1 The location near the mouth pressure
In the disturbance source (such as valves, elbows) downstream and upstream valve test between the disturbance source and the distance not less than 10d, and the distance from the test valve shall be not less than 5d (d is pipe diameter).
6.1.2 Export the location of pressure points
Downstream in the test valve, pilot valve and the distance should be not less than 10d.
6.2 the location of temperature measurement points
Point in the export of downstream pressure, and pressure points and exports should be not less than the distance of 5d.
Flow point measured 6.3 in the downstream temperature measurement and temperature measurement points and the distance should be not less than 5d.
ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com
ABC level measurement
Allow the oil temperature range ± 1.0 ± 2.0 ± 5.0
5.2 Viscosity
At 50 ℃, the oil viscosity for the campaign 17 × l0-6 ~ 43 × 10-6m2 / s.
5.3 filtering accuracy
Oil filters shall not be less than the accuracy of 25μm.
5.4 Test apparatus, precision instruments
5.4.1 According to A, B, C grading of the three measurements to select the appropriate test instruments, meters, type testing should not be less than B-level measurement hierarchy, the factory test should not be less than C-level measurement hierarchy.
5.4.2 When charged with the value of parameter changes in the scope of the instructions in Table 2 provides the framework, it allows measurement of test parameters recorded.
Table 2 was charged with the parameters allowed to change the value of the scope of the instructions
ABC level measurement
Flow% ± 0.5 ± 1.5 ± 2.5
Pressure% ± 0.5 ± 1.5 ± 2.5
Temperature ℃ ± 1.0 ± 2.0 ± 5.0
Viscosity% ± 5 ± 10.0 ± 15
5.4.3 test test instruments, meters shall not exceed the measurement error of the provisions of Table 3.
Table 3 Instruments and Measurement tolerance
ABC level measurement
Flow% ± 0.5 ± 1.5 ± 2.5
Pressure% ± 0.5 ± 1.5 ± 2.5
Temperature ℃ ± 0.5 ± 1.0 ± 2.0
Note: given in Table 3 is chosen by the scope of the apparatus, instruments used in the actual scope of the range of the margin of error allowed.
5.4.4 the preparation of the test report should indicate the level of measurement tests.
6 Test device
6.1 Pressure point
6.1.1 The location near the mouth pressure
In the disturbance source (such as valves, elbows) downstream and upstream valve test between the disturbance source and the distance not less than 10d, and the distance from the test valve shall be not less than 5d (d is pipe diameter).
6.1.2 Export the location of pressure points
Downstream in the test valve, pilot valve and the distance should be not less than 10d.
6.2 the location of temperature measurement points
Point in the export of downstream pressure, and pressure points and exports should be not less than the distance of 5d.
Flow point measured 6.3 in the downstream temperature measurement and temperature measurement points and the distance should be not less than 5d.
ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
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Need, please e-mail to valve401@gmail.com
Butterfly valve in the use of the structure and process problems
At present, the butterfly valve as a pipeline system used for on-off and flow control components, has been in the petroleum, chemical industry, metallurgy, water, electricity and many other fields has been very widely used. The public to know in the butterfly valve technology, the use of its seal form sealed structures, sealing materials for rubber, PTFE and so on. Structural characteristics as a result of the restrictions, not meet high temperature, high pressure and corrosion resistance, abrasion resistance and other industries.
A more advanced existing three eccentricity metal butterfly hard seal butterfly valve, valve body and seat components for the Siamese, the valve seat sealing surface layer welding temperature, corrosion resistant alloy material. Stacked multi-layer soft ring fixed in the valve plate, the butterfly valve butterfly valve as compared with traditional high temperature, operation light, no friction hoist, the closure of the torque transmission mechanism with the increase to compensate for sealing to improve the a butterfly valve sealing performance and durability advantages.
However, this butterfly is still in the course of the following questions:
I, as a result of hard and soft multi-layer stacked ring fixed in the valve plate, when the valve plate when the media always state of the formation of its positive sealing surface erosion, metal film sandwich with the soft seal by erosion, the direct impact on seal performance.
Second, the structural condition of the structure to do the following path DN200 valves, valve plates due to the overall structure of thick, large flow resistance.
Third, due to the structure of the three principles of eccentricity, valve plate and valve seat sealing surface is sealed between the gear on so that the torque pressure to the valve seat. Is flow state, the higher the pressure medium sealed more tightly squeezed. When the medium counter-current flow when the pressure increases with the dielectric plate and the valve seat between the valve units are smaller than the pressure of pressure medium, the seal started to leak.
Two-way high-performance three-eccentric hard-seal butterfly valve, is characterized by: the valve seat ring described by the soft sealing ring on both sides of T-shaped multi-layer film composed of stainless steel. Valve seat plate and the sealing surface for the oblique cone structure, in the oblique conical surface of valve plate welding temperature, corrosion resistant alloy material; fixed loop in the regulation of the spring between the plate and the plate with the adjustment bolt assembly structure.
This structure effectively compensation between the sleeve and the valve stem of the tolerance zone and in the media of elastic deformation under pressure to resolve the two-way valve in the transmission medium of exchange that exist in the process of sealing problems. T-soft on both sides of the use of multi-layer film composed of stainless steel ring with a hard metal sealing and soft sealing the dual advantages of low temperature and high temperature in both cases, all with zero leakage sealing performance.
Pools tested positive flow state (medium flow direction and rotation direction of the same butterfly plate), the sealing surface pressure is the transmission of torque and media pressure on the valve plate of the role. Medium pressure increases toward the valve seat surface and oblique cone sealing surface squeezed more tightly, sealing the better. When the current state, the valve seat plate and the seal between the drive torque on the valve so that pressure to the valve seat. With the increase reverse medium pressure, valve seat plate and between the units is less than the pressure of pressure medium, the adjustment ring is contained in the spring after the deformation energy stored in the compensation of the valve seat sealing surface and the tight the pressure to play the role of automatic compensation. Therefore this utility model, unlike the existing technology, the installation of hardware and software in the on-board multi-valve seals, but directly installed in the valve body, in the middle of plate and the seat adjustment is the addition of a very good two-way sealed hard way . It will be replaced by valve, the cut-off valve and ball valve .Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com
A more advanced existing three eccentricity metal butterfly hard seal butterfly valve, valve body and seat components for the Siamese, the valve seat sealing surface layer welding temperature, corrosion resistant alloy material. Stacked multi-layer soft ring fixed in the valve plate, the butterfly valve butterfly valve as compared with traditional high temperature, operation light, no friction hoist, the closure of the torque transmission mechanism with the increase to compensate for sealing to improve the a butterfly valve sealing performance and durability advantages.
However, this butterfly is still in the course of the following questions:
I, as a result of hard and soft multi-layer stacked ring fixed in the valve plate, when the valve plate when the media always state of the formation of its positive sealing surface erosion, metal film sandwich with the soft seal by erosion, the direct impact on seal performance.
Second, the structural condition of the structure to do the following path DN200 valves, valve plates due to the overall structure of thick, large flow resistance.
Third, due to the structure of the three principles of eccentricity, valve plate and valve seat sealing surface is sealed between the gear on so that the torque pressure to the valve seat. Is flow state, the higher the pressure medium sealed more tightly squeezed. When the medium counter-current flow when the pressure increases with the dielectric plate and the valve seat between the valve units are smaller than the pressure of pressure medium, the seal started to leak.
Two-way high-performance three-eccentric hard-seal butterfly valve, is characterized by: the valve seat ring described by the soft sealing ring on both sides of T-shaped multi-layer film composed of stainless steel. Valve seat plate and the sealing surface for the oblique cone structure, in the oblique conical surface of valve plate welding temperature, corrosion resistant alloy material; fixed loop in the regulation of the spring between the plate and the plate with the adjustment bolt assembly structure.
This structure effectively compensation between the sleeve and the valve stem of the tolerance zone and in the media of elastic deformation under pressure to resolve the two-way valve in the transmission medium of exchange that exist in the process of sealing problems. T-soft on both sides of the use of multi-layer film composed of stainless steel ring with a hard metal sealing and soft sealing the dual advantages of low temperature and high temperature in both cases, all with zero leakage sealing performance.
Pools tested positive flow state (medium flow direction and rotation direction of the same butterfly plate), the sealing surface pressure is the transmission of torque and media pressure on the valve plate of the role. Medium pressure increases toward the valve seat surface and oblique cone sealing surface squeezed more tightly, sealing the better. When the current state, the valve seat plate and the seal between the drive torque on the valve so that pressure to the valve seat. With the increase reverse medium pressure, valve seat plate and between the units is less than the pressure of pressure medium, the adjustment ring is contained in the spring after the deformation energy stored in the compensation of the valve seat sealing surface and the tight the pressure to play the role of automatic compensation. Therefore this utility model, unlike the existing technology, the installation of hardware and software in the on-board multi-valve seals, but directly installed in the valve body, in the middle of plate and the seat adjustment is the addition of a very good two-way sealed hard way . It will be replaced by valve, the cut-off valve and ball valve .Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com
Valve-regulated lead-acid batteries that the technical parameters
UPS (uninterruptible power supply) in the power have been able to continue to supply equipment for the computer because it has a stored energy inside the device at work, which is the UPS energy storage battery of the device. Its main function is: When the normal electricity will be converted into chemical energy stored in the internal battery; power failure when the city will convert chemical energy into electrical energy provided to the inverter or the load. UPS battery is directly related to the merits of the entire UPS system reliability, however, it is the UPS battery system MTBF (MTBF) of a device as soon as possible. If the user can be the proper use and maintenance, will be able to extend its useful life, on the contrary it will significantly shorten the life, the types of batteries in general to play lead-acid batteries, maintenance-free lead-acid batteries and nickel-cadmium batteries. VRLA battery capacity is rated 10-hour rate discharge capacity. Battery discharge current is too large, then less than rated capacity. Therefore, equipment should be based on load, voltage, size and other factors to select the appropriate battery capacity. The total capacity of the battery should be YD5040-97 "communications equipment installation design specifications of power" in the provisions of configuration, calculated as follows: Q ≥ KIT Η [1 + α (t-25)] Where: Q --- battery capacity (Ah); K --- safety factor, from 1.25; I --- Load Current (A); T --- discharge the number of hours (h); Η --- discharge capacity coefficient; t --- the location of the actual battery minimum ambient temperature values. Heating equipment is located there, according to 15 ℃ to consider, no heating equipment, by taking 5 ℃; battery temperature coefficient α --- (1 / ℃), when the discharge rate of ≥ 10 hours, let α = 0.006; when the 10> hour discharge rate of ≥ 1, let α = 0.008; hours when the discharge rate of <1, take α = 0.01. ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com
The technical requirements for procurement of pneumatic valve
Pneumatic valve Purchasing only on a clear specification, type, work pressure to meet the procurement requirements on the practice of a market economy in the current environment is not perfect. Because the pneumatic valve manufacturers for product competition, each pneumatic valve were unified design concept, innovation differently, forming their own company standards and product personality. Therefore, pneumatic valve procurement proposal of a more detailed technical requirements, coordinating with manufacturers to reach a consensus, as a pneumatic valve procurement annex to the contract is very necessary.
1. General Requirements
1.1 Pneumatic valve size and type of pipe should be consistent with the requirements of design documents.
1.2 Pneumatic valves should be specified based on the model numbers of the national standard requirements. If the enterprise standards, should be specified models for instructions.
1.3 Pneumatic valve working pressure ≥ pipeline working pressure, without affecting the price under the premise of the valve can withstand the public pressure should be greater than the actual working pressure pipelines; pneumatic valve closed position, or any side should be able to to withstand 1.1 times the working pressure value instead of the valve leakage; the valve open position, the valve should be able to withstand twice the working pressure valve requirements.
1.4 Pneumatic valve manufacturing standards, should indicate the basis of national standard number, if the enterprise standards, procurement contracts shall be attached to business documents.
2. Pneumatic valve-standard quality
2.1 The valve body material should be ductile iron-based, and indicate the actual grade and the cast iron the physical and chemical test data.
2.2 stem material, and strive to stainless steel stem (2CR13), large diameter valves also should be embedded in the package of stainless steel stem.
2.3 nut material, brass or cast aluminum with cast aluminum bronze, and the hardness and strength are greater than the stem.
2.4 Stem bushing material, its hardness and strength shall be not more than stem, and in the water-soaked conditions and the valve stem, valve did not form a electrochemical corrosion.
2.5 sealing surface of the material
① different categories of pneumatic valve, sealing methods and materials require different;
② Ordinary wedge gate valve, copper rings of material, fixed method, grinding method should show;
③ soft sealing gate valve, the valve plate rubber lining materials, the physical and chemical and health testing data;
④ valve shall be marked on the sealing surface of valve body materials and butterflies on-board sealing surface material; their physical and chemical test data, especially in rubber health requirements, anti-aging properties, wear resistance; usually NBR and ternary B C and rubber, and is strictly prohibited mixed with recycled rubber.
2.6 valve shaft packing
① As the pipe network in the pneumatic valve, normally open and close are not frequent, requiring the filling in a few years of inactivity, filler is not aging, long-term effects remain sealed;
② fill valve shaft should also bear the frequent hoist, the sealing effect of the good nature;
③ In view of the above requirements, the valve shaft packing seek no change in their life or 10 years without replacing them;
④ For replacement of packing, pneumatic valve design should be considered to have a situation of pressure change measures.
3. Speed gearbox
3.1 box and the internal and external anti-corrosion material requirements and body principles.
3.2 The cabinet should be sealed measures assembled box can withstand 3 meters on water-immersion.
3.3 Cabinet on the hoist limit devices, adjustment of nuts or cabinets should be located in boxes outside, but special tools need to be operating.
3.4 Drive structural design is reasonable, open and close valves can only be driven axis, not from top to bottom so that it ran a modest bite transmission parts, does not produce when the separation skid with a load hoisting.
3.5 Variable Speed Drive Cabinet Office with the valve shaft seal is not linked into the overall leak-free, or string should be a reliable anti-leakage measures.
3.6 cabinets without debris, the gear meshing parts of grease should be protected.
4. Pneumatic valve operating mechanism
4.1 pneumatic valve operation of the hoist direction should always be clockwise closing.
4.2 As the pipe network in the pneumatic valve, often manual hoist, hoist a few should not be too much to switch, that is, large-diameter valves should also be within the 200-600 turn.
4.3 In order to facilitate a person's open and close operation, pressure conditions in the plumber, the biggest might be desirable for hoisting torque 240N-m.
4.4 Pneumatic valve open and close operations side should be square tenon, and the size of standardization, and facing the ground so that people can be directly manipulated from the ground. With a wheel valve does not apply to underground pipe network.
4.5 degree of pneumatic valves open and close the display plate
① pneumatic valve open and close degree of scale-line should be cast in the gearbox cover or change the direction of the shell plate after the show, the all facing the ground, scale wire brush on the phosphor in order to show eye-catching;
② directed needle plate in the management of the materials available under better circumstances stainless steel plate, otherwise the painting of the steel plate, not to use aluminum leather production;
③ direct dial & hand eye-catching, fixed solid, once open and close and accurate adjustment, it should be in order to rivet lock.
4.6 If the pneumatic valve buried deep, operating mechanism and display the distance ≥ 1.5m from the ground plate, the pole should have added facilities, and secure a fixed so that people from the ground observation and operation. In other words, pipe network in the valves open and close operation, should not work underground operations.
5. Pneumatic valve performance testing
5.1 valve of a standard high-volume manufacturing, the authoritative body should be entrusted to make the following performance tests:
① valve pressure conditions in the work of hoisting torque;
② in the Public pressure conditions, can guarantee a continuous open and close the valve tightly closed times;
③ valve in the pipeline under the water situation in the resistance coefficient testing.
5.2 The valve should be carried out before leaving the factory the following tests:
① valve in the open position, the valve should withstand twice the value of the valve working pressure of the internal pressure detection;
② valve closure conditions, respectively, on both sides of the valve to withstand 1.1 times the value of public pressure, no leakage; but metal sealed butterfly valve, leakage value is not greater than the relevant requirements.
6. Pneumatic valve's internal and external corrosion
6.1 Body (including the variable speed transmission box) inside and outside, we should first shot blasting sand blasting, and strive to electrostatic spraying epoxy resin powder non-toxic, thickness of 0.3mm or more. Large non-toxic epoxy electrostatic spray valves have difficulties, they should do brushing, spraying a similar non-toxic epoxy paint.
6.2 Valve and valve plate all parts of the house for a full anti-corrosion, on the one hand immersed in water will not rust, in between the two metals does not produce the electrochemical corrosion; two areas over the water resistance of a smooth surface to decrease.
6.3 The valve body paint anti-corrosion epoxy resin or health requirements, there should be the appropriate authority of the organs of test report. Chemical physical properties should also meet the relevant requirements.
7. Pneumatic Valve Packing, Transport
7.1 The valve should be located on both sides of light blocking plate solid seal.
7.2, the small-caliber valve should be bundled straw, and transported in suitable containers.
7.3 The large-diameter valves are also simple framework for solid wood packaging, so as to avoid damage during transport in touch.
8. Pneumatic valve factory specifications
Pneumatic valve is a device in the factory should be marked with the following instructions related to data:
Valve specifications; model; working pressure; manufacturing standards; valve body material; stem material; sealing material; valve shaft packing material; stem sleeve material; internal and external anti-corrosion material; Action start direction; rpm; public pressure conditions Kai closed torque; factory factory name; factory date; serial number; weight; connecting flange diameter, pore number, the center pitch; with graphic images indicate the overall length, width and height of the control size; valve flow resistance coefficient ; the effective open and close times; valve factory testing data and installation, maintenance for attention.
ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com s
1. General Requirements
1.1 Pneumatic valve size and type of pipe should be consistent with the requirements of design documents.
1.2 Pneumatic valves should be specified based on the model numbers of the national standard requirements. If the enterprise standards, should be specified models for instructions.
1.3 Pneumatic valve working pressure ≥ pipeline working pressure, without affecting the price under the premise of the valve can withstand the public pressure should be greater than the actual working pressure pipelines; pneumatic valve closed position, or any side should be able to to withstand 1.1 times the working pressure value instead of the valve leakage; the valve open position, the valve should be able to withstand twice the working pressure valve requirements.
1.4 Pneumatic valve manufacturing standards, should indicate the basis of national standard number, if the enterprise standards, procurement contracts shall be attached to business documents.
2. Pneumatic valve-standard quality
2.1 The valve body material should be ductile iron-based, and indicate the actual grade and the cast iron the physical and chemical test data.
2.2 stem material, and strive to stainless steel stem (2CR13), large diameter valves also should be embedded in the package of stainless steel stem.
2.3 nut material, brass or cast aluminum with cast aluminum bronze, and the hardness and strength are greater than the stem.
2.4 Stem bushing material, its hardness and strength shall be not more than stem, and in the water-soaked conditions and the valve stem, valve did not form a electrochemical corrosion.
2.5 sealing surface of the material
① different categories of pneumatic valve, sealing methods and materials require different;
② Ordinary wedge gate valve, copper rings of material, fixed method, grinding method should show;
③ soft sealing gate valve, the valve plate rubber lining materials, the physical and chemical and health testing data;
④ valve shall be marked on the sealing surface of valve body materials and butterflies on-board sealing surface material; their physical and chemical test data, especially in rubber health requirements, anti-aging properties, wear resistance; usually NBR and ternary B C and rubber, and is strictly prohibited mixed with recycled rubber.
2.6 valve shaft packing
① As the pipe network in the pneumatic valve, normally open and close are not frequent, requiring the filling in a few years of inactivity, filler is not aging, long-term effects remain sealed;
② fill valve shaft should also bear the frequent hoist, the sealing effect of the good nature;
③ In view of the above requirements, the valve shaft packing seek no change in their life or 10 years without replacing them;
④ For replacement of packing, pneumatic valve design should be considered to have a situation of pressure change measures.
3. Speed gearbox
3.1 box and the internal and external anti-corrosion material requirements and body principles.
3.2 The cabinet should be sealed measures assembled box can withstand 3 meters on water-immersion.
3.3 Cabinet on the hoist limit devices, adjustment of nuts or cabinets should be located in boxes outside, but special tools need to be operating.
3.4 Drive structural design is reasonable, open and close valves can only be driven axis, not from top to bottom so that it ran a modest bite transmission parts, does not produce when the separation skid with a load hoisting.
3.5 Variable Speed Drive Cabinet Office with the valve shaft seal is not linked into the overall leak-free, or string should be a reliable anti-leakage measures.
3.6 cabinets without debris, the gear meshing parts of grease should be protected.
4. Pneumatic valve operating mechanism
4.1 pneumatic valve operation of the hoist direction should always be clockwise closing.
4.2 As the pipe network in the pneumatic valve, often manual hoist, hoist a few should not be too much to switch, that is, large-diameter valves should also be within the 200-600 turn.
4.3 In order to facilitate a person's open and close operation, pressure conditions in the plumber, the biggest might be desirable for hoisting torque 240N-m.
4.4 Pneumatic valve open and close operations side should be square tenon, and the size of standardization, and facing the ground so that people can be directly manipulated from the ground. With a wheel valve does not apply to underground pipe network.
4.5 degree of pneumatic valves open and close the display plate
① pneumatic valve open and close degree of scale-line should be cast in the gearbox cover or change the direction of the shell plate after the show, the all facing the ground, scale wire brush on the phosphor in order to show eye-catching;
② directed needle plate in the management of the materials available under better circumstances stainless steel plate, otherwise the painting of the steel plate, not to use aluminum leather production;
③ direct dial & hand eye-catching, fixed solid, once open and close and accurate adjustment, it should be in order to rivet lock.
4.6 If the pneumatic valve buried deep, operating mechanism and display the distance ≥ 1.5m from the ground plate, the pole should have added facilities, and secure a fixed so that people from the ground observation and operation. In other words, pipe network in the valves open and close operation, should not work underground operations.
5. Pneumatic valve performance testing
5.1 valve of a standard high-volume manufacturing, the authoritative body should be entrusted to make the following performance tests:
① valve pressure conditions in the work of hoisting torque;
② in the Public pressure conditions, can guarantee a continuous open and close the valve tightly closed times;
③ valve in the pipeline under the water situation in the resistance coefficient testing.
5.2 The valve should be carried out before leaving the factory the following tests:
① valve in the open position, the valve should withstand twice the value of the valve working pressure of the internal pressure detection;
② valve closure conditions, respectively, on both sides of the valve to withstand 1.1 times the value of public pressure, no leakage; but metal sealed butterfly valve, leakage value is not greater than the relevant requirements.
6. Pneumatic valve's internal and external corrosion
6.1 Body (including the variable speed transmission box) inside and outside, we should first shot blasting sand blasting, and strive to electrostatic spraying epoxy resin powder non-toxic, thickness of 0.3mm or more. Large non-toxic epoxy electrostatic spray valves have difficulties, they should do brushing, spraying a similar non-toxic epoxy paint.
6.2 Valve and valve plate all parts of the house for a full anti-corrosion, on the one hand immersed in water will not rust, in between the two metals does not produce the electrochemical corrosion; two areas over the water resistance of a smooth surface to decrease.
6.3 The valve body paint anti-corrosion epoxy resin or health requirements, there should be the appropriate authority of the organs of test report. Chemical physical properties should also meet the relevant requirements.
7. Pneumatic Valve Packing, Transport
7.1 The valve should be located on both sides of light blocking plate solid seal.
7.2, the small-caliber valve should be bundled straw, and transported in suitable containers.
7.3 The large-diameter valves are also simple framework for solid wood packaging, so as to avoid damage during transport in touch.
8. Pneumatic valve factory specifications
Pneumatic valve is a device in the factory should be marked with the following instructions related to data:
Valve specifications; model; working pressure; manufacturing standards; valve body material; stem material; sealing material; valve shaft packing material; stem sleeve material; internal and external anti-corrosion material; Action start direction; rpm; public pressure conditions Kai closed torque; factory factory name; factory date; serial number; weight; connecting flange diameter, pore number, the center pitch; with graphic images indicate the overall length, width and height of the control size; valve flow resistance coefficient ; the effective open and close times; valve factory testing data and installation, maintenance for attention.
ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com s
Sunday, November 28, 2010
Safety in production and automation technology
First, security of production and automation technology links 1. The meaning of security automation At present, China's weak technological base of production safety, security, science and technology behind the development of production technology, the production of our country's security situation is serious one of the important reasons. Therefore, the country through science and education, science and technology Xing'an strategy, the establishment of long-term mechanism for production safety, safety in production in our country the only way. Rely on scientific and technological progress, and create the essence of security of the operating conditions and operating environment, it is safe to adapt to product development requirements of building a moderately prosperous society of the inevitable choice. Production safety as the protection and development of social productive forces and promoting social and economic sustainable and healthy development of the basic conditions for social civilization and progress is an important indicator of well-off society and the nature of the connotation, but also improve the country's comprehensive national strength and international reputation of the specific embodiment. Automation refers to the machine or device in the absence of intervention by the procedures or instructions to operate automatically or under the control of the process. Automation technology is widely used in industrial agriculture � � � military transport scientific research � � � commercial � medical services and family and so on. Automation technology can be used not only to heavy manual labor from � � some mental work, as well as the risk of poor working environment liberate, but also the expansion of human organ function, significantly improve productivity, enhance human understanding of the world and the ability to change the world . Therefore, the automation of industrial agriculture � � modernization of national defense and science and technology, an important condition and significant signs. Machinery and equipment, systems or processes (production, management processes), or less in the absence of the direct involvement of people, in accordance with the request, after automatic detection, information processing, analysis, manipulation of control, to achieve the desired objectives. Automation technology is to achieve the above objectives of science and technology. Security automation is the implementation of automation technology the use of "science and technology Xing'an" strategy, referred to collectively achieve the safe production. Security automation is specific to the combination of all walks of life have their own different content, such as: coal mine safety in production automation, petrochemical, automation of production safety, chemical safety in production automation, automation of metallurgical production safety, traffic safety, automation, intelligent automation of construction safety in production, other automation of the security industry and so on. 2. Security content automation Called "automated safety" includes the following two aspects: First, the automation of the production process. Factories, mines, cities, the system can not be separated from production activities are the two factors: the production of equipment and the people engaged in production. The existence of security risks is by none other than these two factors. Second, information security and process automation. Both have their own "security content automation" of the content. Of course, there are also foreign experts believe that security is divided into three levels, namely, the personal safety of staff, machinery and equipment, security and security management. "Machine safety" (such as automotive, metal processing, packaging, printing, paper, elevator, etc.) and "safety" (such as coal, metallurgy, chemical, petrochemical, power, etc.) However, there is little or no contradiction between the front Department. In this article, our main target is to explore the production process of the "safety" of automation. Of course, these two aspects of "security automation" is not able to completely separate! As the field of the international community and the increasingly globalized economy, network-based, automated system of production safety, and information security has become more closely linked together. Terrorists, hackers and disgruntled employees there may be a threat, as well as the control system itself fragile and vulnerable characteristics that we must give them adequate protection of its security concerns. Should not lose sight of the control system to strengthen the voice of security continue to rise, this is by no means unfounded! Countries all over the world are increasingly concerned about the manufacturing sector and critical infrastructure of the computer information system has been "cyber" with the danger of the possibility of attack. Similarly, an important basis for manufacturing and industry (such as electricity, water and oil and gas) also began its own extensive attention in the critical plant control systems (DCS, PLC, SCADA systems, HMI and control system network) may be the possibility of attacks by computer .valve ball valve gate valve check valve globe valve butterfly valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com �
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com �
Knife-type valve and the use of technical features of Notes
The use of a knife gate valve gate-type knife with a good shearing, the most appropriate paste, powder aggregates, fiber and other difficult to control the fluid, are widely used in paper making, petrochemical, mining, water, food and other industries. With a variety of seat options, and can be controlled based on demand at the scene, equipped with electric or pneumatic actuators, valve automation to achieve. Material: cast iron, carbon steel, stainless steel Size range: DN50 ~ DN600 maximum pressure: 1.0MPa knife gate valve because of the use of knife-type gate, has a good shearing, the most appropriate paste, powder aggregates, fiber and other difficult to control the fluid, are widely used in paper making, petrochemical, mining, water, food and other industries. With a variety of seat options, and can be controlled based on demand at the scene, equipped with electric or pneumatic actuators, valve automation to achieve. Material: cast iron, carbon steel, stainless steel Size range: DN50 ~ DN600 maximum pressure: 1.0MPa
Knife-type gate valve product use and characteristics of note: the knife-type gate valve is the gate thing, flashboard fluid movement direction and vertical direction, knife-type gate valve can only be full and all related and can not to make adjustments and cut expenditure. There are two gate sealing surface, the most commonly used mode of gate valve sealing surface to form two wedge-shaped, wedge-shaped valve angle parameters vary, usually 50, wedge-type knife gate valve can be made of a whole called rigid ram; can also be made to produce micro-deformation of the gate, so as to improve its process, and cover the sealing surface in the processing point of view of the deviation process, the gate is called a flexible-type knife gate valve closed , can only rely on the sealing surface to seal the pressure medium, which will rely on the medium pressure ram pressure of the sealing surface to the other side of the valve seat to ensure the sealing surface of the seal, which is self-sealing. The majority of knife-type gate valve seal is mandatory, that is, the valve closed, will be forced to rely on external pressure to the valve seat gate to ensure the tightness of the sealing surface.
valve ball valve gate valve check valve globe valve butterfly valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com i
Knife-type gate valve product use and characteristics of note: the knife-type gate valve is the gate thing, flashboard fluid movement direction and vertical direction, knife-type gate valve can only be full and all related and can not to make adjustments and cut expenditure. There are two gate sealing surface, the most commonly used mode of gate valve sealing surface to form two wedge-shaped, wedge-shaped valve angle parameters vary, usually 50, wedge-type knife gate valve can be made of a whole called rigid ram; can also be made to produce micro-deformation of the gate, so as to improve its process, and cover the sealing surface in the processing point of view of the deviation process, the gate is called a flexible-type knife gate valve closed , can only rely on the sealing surface to seal the pressure medium, which will rely on the medium pressure ram pressure of the sealing surface to the other side of the valve seat to ensure the sealing surface of the seal, which is self-sealing. The majority of knife-type gate valve seal is mandatory, that is, the valve closed, will be forced to rely on external pressure to the valve seat gate to ensure the tightness of the sealing surface.
valve ball valve gate valve check valve globe valve butterfly valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com i
Oil and gas industry to the impact of valve technology
Although a century of oil, natural gas development and distribution of products covered by the scope of the valve is basically no change, but the valve manufacturers have continued to update the valve technology, a positive response to oil and gas industry to market changes. If you want to stay ahead in the market or not to be closed, valve manufacturers valve will be continuously updated the design, manufacture, service, sales techniques and processes. The fact is that oil companies on the requirements of the valve more and more: to provide the basis of a reasonable price, advanced valve manufacturers must be good at to solve the problems faced by oil companies, in the working environment even worse, more stringent environmental requirements of the situation , the extension of the valve performance, the ability to provide more services.
(1) metal seal on the world market oil, natural gas demand for the rapid growth in the footsteps of the development of crude oil has also traveled to every corner of the earth, crude oil extraction on new demands on equipment. For example, the ultra-deep technologies on equipment made the challenge of ultra-high pressure ultra-low-moderate. Extraction of crude overweight is optional profitable projects, especially in the crude oil reached 30 dollars a barrel. High concentrations of asphalt now, as well as other impurities Triazene for crude oil transportation and processing difficult. Oil is usually used in the soft-seal ball valve can not meet the requirements of the condition, which requires the development of metal seal valve manufacturers ball valve, and can adapt to temperature, pressure changes, even in the delivery of solid media (hydroxide, coke, etc. ) when it must make sure that absolutely sealed. Metal sealing technology to benefit from the development of surface coating technology. Valve manufacturers want to use this technology to maintain market leadership, and the inclusion of spray technology development strategies, and their research institutes, universities, hopes to develop the next generation of "super hard" coating.
(2) anti-"explosive decompression" In 2002, the American Petroleum Institute standard API 6D provides that: the design pressure of ASME Class 600 higher than the level of valve products must be designed to prevent "explosive decompression." Explosive decompression of the pressure valve means rapid decline, due to infiltration of high pressure in a sealed CO 2 due to the rapid expansion of lower pressure in the valve caused the closure of the process of sealing auriventris and fracture, resulting in the phenomenon of valve failure . An oil platform in the deep valve the first time found that the phenomenon of explosive decompression, the valve immediately after the expiration of the company had ceased operations a few weeks to replace the valve, resulting in heavy losses. From then on, the oil companies asked to provide the high-pressure valve manufacturers with anti-valve must be "explosive decompression" configuration. Soon, valve manufacturers to respond quickly to the development of anti-"explosive decompression" sealed and anti-"explosive decompression" valve in response to harsh environmental requirements.
(3) corrosion of the high sulfur content crude oil prices make oil refining companies to look on the sulfur content of crude oil, the sulfur content of the crude oil market investing in the development of lucrative, long-term supply contract prices are also competitive advantages. But the content of crude oil contains H 2 S and other corrosive medium, corrosion resistance of equipment to the new challenges. Valve manufacturer can provide the materials license ISO15156 requirements, but also provide the pilot (according to the provisions of ISO15156) data to prove that the corrosion resistance of the valve materials and long-life, end-user then the manufacturer of these valves to include corrosion-resistant valve list of suppliers.
(4) emissions飞逸provides for ISO15848 emissions飞逸valve design, manufacturers redesigned the general valve and special valve packing, sealing order to meet the updated standard. However, the new standard is too general, the requirements are too strict, so there are many oil companies to develop its own emission standards, for example, many North American companies with reference to API 622 standards. Valve飞逸of emission standards to further improve the needs of the valve manufacturers, users, standard-setters tripartite cooperation, learn from each other experience, the three parties together to resolve.
(5) in advance of fatigue wear and equipment for the pursuit of economic interests, many refineries are running overload. The result is endless capacity production equipment and improvement of the system. Business-to-equipment far exceeded the expectations of the original design, which requires manufacturers to take precautions valves, active participation of all users of the work of the production process to avoid an unreasonable design of the valve reliability, longevity and security of the adverse effects. For example, the application of heat in the circulatory system caused by parts of the valve easier to thermal fatigue, with experience in industrial processes valve valve manufacturer will make reasonable arrangements to reduce the possibility of problems.
(6) preventive maintenance of oil companies in order to ensure the production, arrangement for equipment maintenance cycle. With the valve test systems, electronic hardware, software development, preventive maintenance valves has been the concept of intelligence into a reality. Proficient in a small portion of the valve automation and control manufacturers to provide data analysis system to quantify the valve operation to provide time for preventive maintenance valve.
(7) self-executing agencies refining process automation is the trend, which has been the middle of the development of control technology for a long period of time. Valve manufacturers to install an automatic valve on executing agencies in order to achieve automatic control of production requirements. Self-executing agencies to develop great technology. On the other hand, the production of the executing agency of the manufacturers to provide users with the installation of the executive body of the valve products. Thus, the executive body of the trend of integration and the valve manufacturer for the formation of a single challenge, after all, a business user wants to find it easier to solve the problem in order to avoid the phenomenon of passing.
(8) natural gas transport pipeline ball valve on the valve for the pipeline project is a very large potential market. Of long-distance pipeline monitoring is very important. It has developed a smart device, the user can be used for detection of the pipeline. For example, "smart pig" technology. This robot can detect the thickness of the wall, and even corrosion points. Detection device on the pipeline but there is the request path, so the ball valve has become the path of long-distance company of choice for pipeline products. On the other hand, long-distance pipeline as far as possible the requirements of thin wall thickness of the valve, the valve material has a high yield toughness, corrosion resistance, to meet the telescopic pipes, steering, changing requirements of the local environment. The most important point is that managers of long-distance pipeline valves require the purchase of life must be longer than the life of the pipeline itself. valve ball valve gate valve check valve globe valve butterfly valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com e
(1) metal seal on the world market oil, natural gas demand for the rapid growth in the footsteps of the development of crude oil has also traveled to every corner of the earth, crude oil extraction on new demands on equipment. For example, the ultra-deep technologies on equipment made the challenge of ultra-high pressure ultra-low-moderate. Extraction of crude overweight is optional profitable projects, especially in the crude oil reached 30 dollars a barrel. High concentrations of asphalt now, as well as other impurities Triazene for crude oil transportation and processing difficult. Oil is usually used in the soft-seal ball valve can not meet the requirements of the condition, which requires the development of metal seal valve manufacturers ball valve, and can adapt to temperature, pressure changes, even in the delivery of solid media (hydroxide, coke, etc. ) when it must make sure that absolutely sealed. Metal sealing technology to benefit from the development of surface coating technology. Valve manufacturers want to use this technology to maintain market leadership, and the inclusion of spray technology development strategies, and their research institutes, universities, hopes to develop the next generation of "super hard" coating.
(2) anti-"explosive decompression" In 2002, the American Petroleum Institute standard API 6D provides that: the design pressure of ASME Class 600 higher than the level of valve products must be designed to prevent "explosive decompression." Explosive decompression of the pressure valve means rapid decline, due to infiltration of high pressure in a sealed CO 2 due to the rapid expansion of lower pressure in the valve caused the closure of the process of sealing auriventris and fracture, resulting in the phenomenon of valve failure . An oil platform in the deep valve the first time found that the phenomenon of explosive decompression, the valve immediately after the expiration of the company had ceased operations a few weeks to replace the valve, resulting in heavy losses. From then on, the oil companies asked to provide the high-pressure valve manufacturers with anti-valve must be "explosive decompression" configuration. Soon, valve manufacturers to respond quickly to the development of anti-"explosive decompression" sealed and anti-"explosive decompression" valve in response to harsh environmental requirements.
(3) corrosion of the high sulfur content crude oil prices make oil refining companies to look on the sulfur content of crude oil, the sulfur content of the crude oil market investing in the development of lucrative, long-term supply contract prices are also competitive advantages. But the content of crude oil contains H 2 S and other corrosive medium, corrosion resistance of equipment to the new challenges. Valve manufacturer can provide the materials license ISO15156 requirements, but also provide the pilot (according to the provisions of ISO15156) data to prove that the corrosion resistance of the valve materials and long-life, end-user then the manufacturer of these valves to include corrosion-resistant valve list of suppliers.
(4) emissions飞逸provides for ISO15848 emissions飞逸valve design, manufacturers redesigned the general valve and special valve packing, sealing order to meet the updated standard. However, the new standard is too general, the requirements are too strict, so there are many oil companies to develop its own emission standards, for example, many North American companies with reference to API 622 standards. Valve飞逸of emission standards to further improve the needs of the valve manufacturers, users, standard-setters tripartite cooperation, learn from each other experience, the three parties together to resolve.
(5) in advance of fatigue wear and equipment for the pursuit of economic interests, many refineries are running overload. The result is endless capacity production equipment and improvement of the system. Business-to-equipment far exceeded the expectations of the original design, which requires manufacturers to take precautions valves, active participation of all users of the work of the production process to avoid an unreasonable design of the valve reliability, longevity and security of the adverse effects. For example, the application of heat in the circulatory system caused by parts of the valve easier to thermal fatigue, with experience in industrial processes valve valve manufacturer will make reasonable arrangements to reduce the possibility of problems.
(6) preventive maintenance of oil companies in order to ensure the production, arrangement for equipment maintenance cycle. With the valve test systems, electronic hardware, software development, preventive maintenance valves has been the concept of intelligence into a reality. Proficient in a small portion of the valve automation and control manufacturers to provide data analysis system to quantify the valve operation to provide time for preventive maintenance valve.
(7) self-executing agencies refining process automation is the trend, which has been the middle of the development of control technology for a long period of time. Valve manufacturers to install an automatic valve on executing agencies in order to achieve automatic control of production requirements. Self-executing agencies to develop great technology. On the other hand, the production of the executing agency of the manufacturers to provide users with the installation of the executive body of the valve products. Thus, the executive body of the trend of integration and the valve manufacturer for the formation of a single challenge, after all, a business user wants to find it easier to solve the problem in order to avoid the phenomenon of passing.
(8) natural gas transport pipeline ball valve on the valve for the pipeline project is a very large potential market. Of long-distance pipeline monitoring is very important. It has developed a smart device, the user can be used for detection of the pipeline. For example, "smart pig" technology. This robot can detect the thickness of the wall, and even corrosion points. Detection device on the pipeline but there is the request path, so the ball valve has become the path of long-distance company of choice for pipeline products. On the other hand, long-distance pipeline as far as possible the requirements of thin wall thickness of the valve, the valve material has a high yield toughness, corrosion resistance, to meet the telescopic pipes, steering, changing requirements of the local environment. The most important point is that managers of long-distance pipeline valves require the purchase of life must be longer than the life of the pipeline itself. valve ball valve gate valve check valve globe valve butterfly valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
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Ceramic wear-resistant valve features and future development trend
China valves commonly used in industry for metal valves, metal valve has been the use of the history of a century, although the metal valve through the improvement of structure and materials, subject to the restrictions on the properties of metallic materials, can not meet the increasingly high wear and tear, corrosion, such as strong demand for the poor working conditions, mainly reflected in the life of a short, serious leaks have greatly affected the stability of system operation. In urgent need of the traditional metal valves from the materials, design and manufacturing process innovation and so thorough. Ceramic materials to be used in the industrial valve is a bold and useful innovation. Deformation of ceramic materials is very small, much higher than the metal with a combination of strength, generally composed of ceramic materials under the crystal ionic radius of the small and high-ion price, with the median, and these determine the nature of the tensile strength of ceramic materials strength, compressive strength, elastic modulus, hardness, etc. is very high. Ceramic itself, however the "brittle" and difficult-to-machine limited its scope of application, over the past decade over the past few years, as a result of martensitic transformation toughening technology, composite materials technology and nano-ceramic Section the concept of development and progress, has made ceramics " brittleness "have been greatly improved, and its toughness and strength has been greatly improved, expanding the scope of application.
In recent years, new types of ceramic materials in petroleum, chemical, and mechanical applications, such as very active using the wear resistance of ceramics, the production of wear-resistant Corrosion resistant parts of the Department in lieu of metal materials, high-tech materials in recent years the importance of market One direction of development. Social and economic benefits of ceramic valves: 1. Ceramic valve structure using high-tech ceramic materials new valve sealing components and vulnerable parts of the valve products to improve resistance to abrasion, corrosion and sealing, greatly extended the valve door life. 2. The use of ceramic valves can significantly reduce the number of valve replacement maintenance, equipment operation to improve security and stability, saving the cost of repairing equipment. 3. The use of ceramic valves can improve the sealing of industrial piping systems, to reduce the maximum leakage, thereby protecting the environment. 4. To create a wide range of ceramic raw materials, low-cost, aluminum, carbon, silicon and other non-Su-general will be able to create superior performance ceramic materials, can save a large number of rare metal materials and mineral resources. Wear-resistant ceramic valves are mainly used in electric power, petroleum, chemical, metallurgy, mining, sewage treatment and other industrial fields, especially in the face of high wear and tear, strong corrosion, high temperature, high pressure, such as poor working conditions, ceramic valve showed its excellent performance. Ceramic valves to meet the high wear and tear, the use of strong corrosive environment, in particular, is a prominent feature of the ultra-long life, ceramic valves are far superior to other similar cost-effective metal valve. With the continuous development of science and technology and progress of, ceramic materials from the formulation, molding, machining and assembly process technology and other more mature and complete, ceramic valves for its excellent performance has been a growing recognition of the valve industry . Manufacture of ceramics using the successful experience of the valve can also be used to promote a wider range of engineering fields.
ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
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In recent years, new types of ceramic materials in petroleum, chemical, and mechanical applications, such as very active using the wear resistance of ceramics, the production of wear-resistant Corrosion resistant parts of the Department in lieu of metal materials, high-tech materials in recent years the importance of market One direction of development. Social and economic benefits of ceramic valves: 1. Ceramic valve structure using high-tech ceramic materials new valve sealing components and vulnerable parts of the valve products to improve resistance to abrasion, corrosion and sealing, greatly extended the valve door life. 2. The use of ceramic valves can significantly reduce the number of valve replacement maintenance, equipment operation to improve security and stability, saving the cost of repairing equipment. 3. The use of ceramic valves can improve the sealing of industrial piping systems, to reduce the maximum leakage, thereby protecting the environment. 4. To create a wide range of ceramic raw materials, low-cost, aluminum, carbon, silicon and other non-Su-general will be able to create superior performance ceramic materials, can save a large number of rare metal materials and mineral resources. Wear-resistant ceramic valves are mainly used in electric power, petroleum, chemical, metallurgy, mining, sewage treatment and other industrial fields, especially in the face of high wear and tear, strong corrosion, high temperature, high pressure, such as poor working conditions, ceramic valve showed its excellent performance. Ceramic valves to meet the high wear and tear, the use of strong corrosive environment, in particular, is a prominent feature of the ultra-long life, ceramic valves are far superior to other similar cost-effective metal valve. With the continuous development of science and technology and progress of, ceramic materials from the formulation, molding, machining and assembly process technology and other more mature and complete, ceramic valves for its excellent performance has been a growing recognition of the valve industry . Manufacture of ceramics using the successful experience of the valve can also be used to promote a wider range of engineering fields.
ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com u
Thermostatic radiator control valves, Principle and Application
Thermostatic radiator control valves in the 40's as early as the 20th century in Europe, in the early 80s our country has begun to develop and radiator temperature control valve, into the 90's, the latter, with the heat metering policy and technology and the deepening masses of the people of personalized room temperature requirements, a variety of domestic, import radiator temperature control valve products came into being, and many of its projects in China were used.
In the radiator heating the room temperature control can be used to control the radiator temperature control valve, but also better resistance characteristics can be manually controlled valves. Thermostatic radiator valve control of the use of the advantage of being able to control better the use of "free heat" to achieve the purpose of energy conservation, while avoiding the user to repeatedly adjust cumbersome.
First, the radiator temperature control valve as well as the breakdown of the working principle
Radiator temperature control valve and valve body from the temperature controller is composed of two parts. Principles of its users will spin the controller to the desired temperature setting temperature, when the room temperature exceeds the set temperature, the thermostat temperature controller inside the package (with sufficient medium temperature) thermal expansion, the volume increased to promote the stem, the valve clearance small, reducing the water flow radiator, so that at room temperature to reach set temperature. When the indoor temperature below the set temperature, the temperature by the cold shrink package size decreases, with the reset spring spool stem back to the valve opening, increasing the radiator water flow until the temperature reached for value.
1. Thermostatic controller
Thermostat temperature controller package in accordance with its location can be divided into built-in temperature and package type FarEasTone. Package due to feelings of warm ambient air temperature is at the same time regulating valve action as well as changes in temperature have a packet size, so the location of temperature package for the importance of the proper use of valves. In most cases, the need to adjust the radiator in this group are the indoor room temperature, the built package suitable temperature valves. In some specific cases, such as the radiator in this group was blocking the radiator cover, valve cover is located within, or close valves, there are other hot (cold) source, such as cooking, lighting and so strong when the temperature is around the package of local feeling the heat, the room temperature is not accurate, they are advised to adopt FarEasTone type thermostat controller, the sensor can accurately adjust at room temperature suffered strong interference with the smaller local sources of heat in order to achieve accurate control The purpose of the room temperature. In some special systems, such as the level of single-pipe systems, can only be installed in the first group of radiator radiator valves, and adjust the user used the living room or master bedroom room temperature mainly, but also can be FarEasTone type valves, temperature sensors will be placed in the living room or master bedroom collected regulate its temperature. (1) steam temperature-inclusive.
Wen package filled with the medium as a low boiling point liquid, when the outside temperature, some of vaporization of the liquid as a gas, temperature increase packet size to promote stem off a small valve opening, into the radiator into the reduced water flow, when the outside temperature decreases, some of liquefied gas and a liquid, reducing the temperature package size, increase valve opening thereby increasing the influent flow radiator. The temperature inside the package temperature of a gas-liquid media are often mixed, and the role of time since the advantages of rapid, but the package seal temperature requirement is very stringent, very little in the domestic application.
(2) the liquid temperature-inclusive.
Bag filled with warm temperature of the liquid medium for special, general, such as methanol or toluene. Larger packages such temperature, short time, the current in the wider domestic applications.
(3) solid-state temperature-inclusive.
Wen bag is filled with high expansion coefficient of solids, such as for the paraffin. Because of the relative gas and liquid solid heat (cold) the smaller volume, so its temperature moves slower, but the relative volume of small packet of liquid temperature in the domestic as well as some applications.
(4) metal plate.
Its temperature controllers for temperature device with a special memory metal alloys, the thermal expansion of metal sheets by cold contraction driven valve action. Before the factory such products to its strict temperature devices and testing of the experiment at the same time, as a result of metal in frequent after stretching and bending characteristics, such as the existence of changes in fatigue fracture, and ductile metal with, so will such a sense of temperature devices affect the life and accuracy. Some manufacturers to produce products such valves, rarely seen their foreign products.
2. Thermostatic valve body
Valve body is generally made of copper, nickel appearance, in accordance with its inlet and outlet temperature controller is installed between the valve core can be divided into the following point of view.
(1) straight-through-type valve Valve: inlet and outlet valves for the 180-degree angle.
(2)-angle valve Valve: inlet and outlet valves for the 90-degree angle.
(3) three-dimensional valve body (valve three-dimensional): inlet valve, the valve core into the water and a 90-degree angle, similar to X, Y, Z coordinates.
(4) The special combination of valve body: for some new radiator (such as the bathroom radiator, etc.) and some connections (for example, by leaps and bounds in single-tube), many manufacturers also introduced a number of special temperature-controlled modular valve body. Not in this list.
Products abroad, the water regulating valve resistance value tends to be used Kv said a lot of Chinese-made products are used valve Kv value labeled water resistance characteristics. Kv value is defined as the regulating valve in the valve before the valve after the pressure drop for 1bar through the flow control valve. Kvs value of said regulating valve opening when the largest value of Kv. The following formula can be converted to Kv value commonly used in the local drag coefficient.
Second, the radiator valve radiator system in a variety of the proper use of
1. In our country most of the old radiator heating system is used in vertical up and down through the single-tube or twin-tube system.
(1) in the vertical single-pipe system, radiator water, the former group all through the next set of radiators, each radiator and is located in a different floor, radiator thermostatic valve can not be installed. Could be considered for such a system of vertical single-pipe system, so that the radiator can be installed in each valve or adjust the properties of a good manual control valve.
(2) in the vertical double-pipe system, due to the existence of vertical imbalance in the system can be installed with pre-setting function of the radiator valves. That is, the so-called pre-set features on the valve body with a pre-set the initial resistance of the device, the device will be available through the initial resistance valve settings, different floors of the initial resistance between the different settings can be certain solve the problem of vertical imbalance. However, this method to be used in practice do the following. Designers to do more detailed hydraulic calculation. Installation, construction has to carefully than on the provision of water supply manufacturers resistance flow chart will be accurate thermostatic valve to pre-set position. After running in the water, can be carried out in accordance with the specific circumstances of individual adjustments. Two-pipe system as a result of the high-resistance valve (after the details of the text will do), at the same time pre-set regulator further reduces the valve opening, so a higher quality of the heating requirements, otherwise easily cause obstruction.
2. In recent years, with household heat metering technology continues to develop, in the majority of the civil and industrial construction in the level of indoor household heating systems based ring was broad applications, is also designed with a maximum of kinds of indoor heating arrangement. Heating radiator layout is divided into levels: the level of single-type pipe (not allowed in the standard, non-recommended), the level of single-tube by leaps and bounds, on a twin-tube fraction, fraction of a twin-tube, radiation dual - tube a few major categories.
(1) the level of single-pipe type: horizontal single-pipe system with the earlier single-pipe vertical systems are similar, the heating water flowing through the radiator before a group of the next group after the full flow of cooling , and therefore should not be installed on each radiator valves or manual valves. This valve system is installed, consideration may be given in the first group of the front radiator inlet valve installed in the vicinity of Far, Far EasTone will valve temperature control sensors to be placed in the main room, such as master bedroom, living room . The drawbacks of this arrangement is to move through the valve, will lead to heating the entire room changes in water flow, and valve signal acquisition is only room for one of the signal, then there will be other room temperature fluctuations and precision can not be effective regulation. In this way could also be considered in the first group to install high-quality front-end radiator, opening with the linear relationship between flow control valve manually through the control valve regulating the system of rough. Radiator arrangement such as "standards" are not allowed, we do not recommend using this approach.
(2) the level of single-tube by leaps and bounds: the level of single-tube by leaps and bounds in recent years the application of a more interior arrangement has the merit of each radiator can be accurate for temperature control, adapted to the user's personalized home requirements, but also in line with the "household metering, sub-room temperature" of the policy requirements. At the same time as some high-temperature hot water (not through the radiator heat exchanger) flows to the next group of radiators, the next group to raise the water temperature of the radiator to ensure the quality of the heating.
Compared with other household level for the indoor ring arrangement, by leaps and bounds in single-tube is a relatively simple to adapt to a wide range of layout. In specific applications, according to the use of a variety of valve products (hand control valve) and its applications are many different forms.
In this way a relatively simple structure, low cost. However, in practical applications, there are some problems. Many of its projects, because of indiscriminate use of high resistance of the two-valve, causing the volume of hot water into the radiator is too small. Some works, some of the wrong usage, in order to meet the needs of the radiator into the water, across the tube had to install a regulator valve to increase the resistance across the tube part. Even with the low resistance to the two pass radiator valves should also factor into the calculation of flow. Radiator inlet channel coefficient is part of the radiator and across the tube part of the ratio of channel resistance. Increase in the level of single-tube across the tube system, generally more than 30%, to ensure the water flow radiator. However, this calculation more complicated.
(2.2) the form of bypass valve
In order to adapt to the indoor levels are one-pipe system plus applications across a number of manufacturers introduced a special kind of bypass valve, the valve to the radiator such access (including valve) and a combination of bypass slip overall, and slip into a bypass resistance adjustable bypass valve. The advantage for simplifying the calculation and installation, as the bypass ratio is adjustable to adapt to a wide range of systems, based on the specific circumstances of a separate regulation.
Such a bypass valve can also be calculated into the flow coefficient of the radiator. In some projects have already been adopted gradually.
(2.3) other special form of valve
Currently on the market there were a lot of new forms of the radiator, in order to meet these new radiator, all kinds of special form of valve products came into being.
(3) the level of the form of twin-tube.
Indoor levels of a twin-tube can also be installed in each water radiator valves, to carry out sub-room temperature control. The use of such arrangement, heating of good quality can be multiple sets of radiator series of different radiator valves regulate the system through the impact of small, but regardless of the fraction or fraction of the level of twin-tube arrangement, the interior more complicated pipeline arrangement, the overall decoration of the room, looking a certain effect.
And vertical layout of such a dual-track system, the greater the resistance due to the end, the system the smaller the volatility of its impact, it should choose the high resistance of the radiator valves.
(4) twin-tube radiation.
Such arrangements have also been known as the "octopus-style" layout, but also the level of belonging to the indoor area of a twin-tube. In the household at the entrance to the installation of a / watershed, and sub / catchment一环讲each device connected to a radiator. The advantage of flexible arrangements, which will help to carry out at room temperature, but more complex arrangement of pipes, cost over the previous several high indoor layout. In such a system should also refer to two-pipe system using high-resistance valve, if the use of reliable manual control valve can be installed in the inlet end of each radiator can be installed in each sub-path / Set Water carrying out centralized control.
In August 2003, the MOC issued a "Circular on the work of the urban heating system reform guidance" clearly stipulates that in the future, new public buildings and town houses, where the use of central heating facilities must be designed, installed splitting with temperature measurement and heating system control functions, and implementation of household energy use metering and charging of the new approach. Into the 21st century, the broad masses of the people on energy saving and thermal comfort of the continually increasing demands from household metering, at room temperature has been the policy of the people. Radiator valves will also be more widely used. However, the valve can not be a simple matter of a loaded, the system uses different forms of what kind of valve or other manual control valve, required careful calculation and products based on insight into the basis of At the same time, the installation and post-testing also should be consistent with good design and manufacturers of communication, in accordance with appropriate adjustments to the specific circumstances in order to achieve full and fair use purposes.
ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com t
In the radiator heating the room temperature control can be used to control the radiator temperature control valve, but also better resistance characteristics can be manually controlled valves. Thermostatic radiator valve control of the use of the advantage of being able to control better the use of "free heat" to achieve the purpose of energy conservation, while avoiding the user to repeatedly adjust cumbersome.
First, the radiator temperature control valve as well as the breakdown of the working principle
Radiator temperature control valve and valve body from the temperature controller is composed of two parts. Principles of its users will spin the controller to the desired temperature setting temperature, when the room temperature exceeds the set temperature, the thermostat temperature controller inside the package (with sufficient medium temperature) thermal expansion, the volume increased to promote the stem, the valve clearance small, reducing the water flow radiator, so that at room temperature to reach set temperature. When the indoor temperature below the set temperature, the temperature by the cold shrink package size decreases, with the reset spring spool stem back to the valve opening, increasing the radiator water flow until the temperature reached for value.
1. Thermostatic controller
Thermostat temperature controller package in accordance with its location can be divided into built-in temperature and package type FarEasTone. Package due to feelings of warm ambient air temperature is at the same time regulating valve action as well as changes in temperature have a packet size, so the location of temperature package for the importance of the proper use of valves. In most cases, the need to adjust the radiator in this group are the indoor room temperature, the built package suitable temperature valves. In some specific cases, such as the radiator in this group was blocking the radiator cover, valve cover is located within, or close valves, there are other hot (cold) source, such as cooking, lighting and so strong when the temperature is around the package of local feeling the heat, the room temperature is not accurate, they are advised to adopt FarEasTone type thermostat controller, the sensor can accurately adjust at room temperature suffered strong interference with the smaller local sources of heat in order to achieve accurate control The purpose of the room temperature. In some special systems, such as the level of single-pipe systems, can only be installed in the first group of radiator radiator valves, and adjust the user used the living room or master bedroom room temperature mainly, but also can be FarEasTone type valves, temperature sensors will be placed in the living room or master bedroom collected regulate its temperature. (1) steam temperature-inclusive.
Wen package filled with the medium as a low boiling point liquid, when the outside temperature, some of vaporization of the liquid as a gas, temperature increase packet size to promote stem off a small valve opening, into the radiator into the reduced water flow, when the outside temperature decreases, some of liquefied gas and a liquid, reducing the temperature package size, increase valve opening thereby increasing the influent flow radiator. The temperature inside the package temperature of a gas-liquid media are often mixed, and the role of time since the advantages of rapid, but the package seal temperature requirement is very stringent, very little in the domestic application.
(2) the liquid temperature-inclusive.
Bag filled with warm temperature of the liquid medium for special, general, such as methanol or toluene. Larger packages such temperature, short time, the current in the wider domestic applications.
(3) solid-state temperature-inclusive.
Wen bag is filled with high expansion coefficient of solids, such as for the paraffin. Because of the relative gas and liquid solid heat (cold) the smaller volume, so its temperature moves slower, but the relative volume of small packet of liquid temperature in the domestic as well as some applications.
(4) metal plate.
Its temperature controllers for temperature device with a special memory metal alloys, the thermal expansion of metal sheets by cold contraction driven valve action. Before the factory such products to its strict temperature devices and testing of the experiment at the same time, as a result of metal in frequent after stretching and bending characteristics, such as the existence of changes in fatigue fracture, and ductile metal with, so will such a sense of temperature devices affect the life and accuracy. Some manufacturers to produce products such valves, rarely seen their foreign products.
2. Thermostatic valve body
Valve body is generally made of copper, nickel appearance, in accordance with its inlet and outlet temperature controller is installed between the valve core can be divided into the following point of view.
(1) straight-through-type valve Valve: inlet and outlet valves for the 180-degree angle.
(2)-angle valve Valve: inlet and outlet valves for the 90-degree angle.
(3) three-dimensional valve body (valve three-dimensional): inlet valve, the valve core into the water and a 90-degree angle, similar to X, Y, Z coordinates.
(4) The special combination of valve body: for some new radiator (such as the bathroom radiator, etc.) and some connections (for example, by leaps and bounds in single-tube), many manufacturers also introduced a number of special temperature-controlled modular valve body. Not in this list.
Products abroad, the water regulating valve resistance value tends to be used Kv said a lot of Chinese-made products are used valve Kv value labeled water resistance characteristics. Kv value is defined as the regulating valve in the valve before the valve after the pressure drop for 1bar through the flow control valve. Kvs value of said regulating valve opening when the largest value of Kv. The following formula can be converted to Kv value commonly used in the local drag coefficient.
Second, the radiator valve radiator system in a variety of the proper use of
1. In our country most of the old radiator heating system is used in vertical up and down through the single-tube or twin-tube system.
(1) in the vertical single-pipe system, radiator water, the former group all through the next set of radiators, each radiator and is located in a different floor, radiator thermostatic valve can not be installed. Could be considered for such a system of vertical single-pipe system, so that the radiator can be installed in each valve or adjust the properties of a good manual control valve.
(2) in the vertical double-pipe system, due to the existence of vertical imbalance in the system can be installed with pre-setting function of the radiator valves. That is, the so-called pre-set features on the valve body with a pre-set the initial resistance of the device, the device will be available through the initial resistance valve settings, different floors of the initial resistance between the different settings can be certain solve the problem of vertical imbalance. However, this method to be used in practice do the following. Designers to do more detailed hydraulic calculation. Installation, construction has to carefully than on the provision of water supply manufacturers resistance flow chart will be accurate thermostatic valve to pre-set position. After running in the water, can be carried out in accordance with the specific circumstances of individual adjustments. Two-pipe system as a result of the high-resistance valve (after the details of the text will do), at the same time pre-set regulator further reduces the valve opening, so a higher quality of the heating requirements, otherwise easily cause obstruction.
2. In recent years, with household heat metering technology continues to develop, in the majority of the civil and industrial construction in the level of indoor household heating systems based ring was broad applications, is also designed with a maximum of kinds of indoor heating arrangement. Heating radiator layout is divided into levels: the level of single-type pipe (not allowed in the standard, non-recommended), the level of single-tube by leaps and bounds, on a twin-tube fraction, fraction of a twin-tube, radiation dual - tube a few major categories.
(1) the level of single-pipe type: horizontal single-pipe system with the earlier single-pipe vertical systems are similar, the heating water flowing through the radiator before a group of the next group after the full flow of cooling , and therefore should not be installed on each radiator valves or manual valves. This valve system is installed, consideration may be given in the first group of the front radiator inlet valve installed in the vicinity of Far, Far EasTone will valve temperature control sensors to be placed in the main room, such as master bedroom, living room . The drawbacks of this arrangement is to move through the valve, will lead to heating the entire room changes in water flow, and valve signal acquisition is only room for one of the signal, then there will be other room temperature fluctuations and precision can not be effective regulation. In this way could also be considered in the first group to install high-quality front-end radiator, opening with the linear relationship between flow control valve manually through the control valve regulating the system of rough. Radiator arrangement such as "standards" are not allowed, we do not recommend using this approach.
(2) the level of single-tube by leaps and bounds: the level of single-tube by leaps and bounds in recent years the application of a more interior arrangement has the merit of each radiator can be accurate for temperature control, adapted to the user's personalized home requirements, but also in line with the "household metering, sub-room temperature" of the policy requirements. At the same time as some high-temperature hot water (not through the radiator heat exchanger) flows to the next group of radiators, the next group to raise the water temperature of the radiator to ensure the quality of the heating.
Compared with other household level for the indoor ring arrangement, by leaps and bounds in single-tube is a relatively simple to adapt to a wide range of layout. In specific applications, according to the use of a variety of valve products (hand control valve) and its applications are many different forms.
In this way a relatively simple structure, low cost. However, in practical applications, there are some problems. Many of its projects, because of indiscriminate use of high resistance of the two-valve, causing the volume of hot water into the radiator is too small. Some works, some of the wrong usage, in order to meet the needs of the radiator into the water, across the tube had to install a regulator valve to increase the resistance across the tube part. Even with the low resistance to the two pass radiator valves should also factor into the calculation of flow. Radiator inlet channel coefficient is part of the radiator and across the tube part of the ratio of channel resistance. Increase in the level of single-tube across the tube system, generally more than 30%, to ensure the water flow radiator. However, this calculation more complicated.
(2.2) the form of bypass valve
In order to adapt to the indoor levels are one-pipe system plus applications across a number of manufacturers introduced a special kind of bypass valve, the valve to the radiator such access (including valve) and a combination of bypass slip overall, and slip into a bypass resistance adjustable bypass valve. The advantage for simplifying the calculation and installation, as the bypass ratio is adjustable to adapt to a wide range of systems, based on the specific circumstances of a separate regulation.
Such a bypass valve can also be calculated into the flow coefficient of the radiator. In some projects have already been adopted gradually.
(2.3) other special form of valve
Currently on the market there were a lot of new forms of the radiator, in order to meet these new radiator, all kinds of special form of valve products came into being.
(3) the level of the form of twin-tube.
Indoor levels of a twin-tube can also be installed in each water radiator valves, to carry out sub-room temperature control. The use of such arrangement, heating of good quality can be multiple sets of radiator series of different radiator valves regulate the system through the impact of small, but regardless of the fraction or fraction of the level of twin-tube arrangement, the interior more complicated pipeline arrangement, the overall decoration of the room, looking a certain effect.
And vertical layout of such a dual-track system, the greater the resistance due to the end, the system the smaller the volatility of its impact, it should choose the high resistance of the radiator valves.
(4) twin-tube radiation.
Such arrangements have also been known as the "octopus-style" layout, but also the level of belonging to the indoor area of a twin-tube. In the household at the entrance to the installation of a / watershed, and sub / catchment一环讲each device connected to a radiator. The advantage of flexible arrangements, which will help to carry out at room temperature, but more complex arrangement of pipes, cost over the previous several high indoor layout. In such a system should also refer to two-pipe system using high-resistance valve, if the use of reliable manual control valve can be installed in the inlet end of each radiator can be installed in each sub-path / Set Water carrying out centralized control.
In August 2003, the MOC issued a "Circular on the work of the urban heating system reform guidance" clearly stipulates that in the future, new public buildings and town houses, where the use of central heating facilities must be designed, installed splitting with temperature measurement and heating system control functions, and implementation of household energy use metering and charging of the new approach. Into the 21st century, the broad masses of the people on energy saving and thermal comfort of the continually increasing demands from household metering, at room temperature has been the policy of the people. Radiator valves will also be more widely used. However, the valve can not be a simple matter of a loaded, the system uses different forms of what kind of valve or other manual control valve, required careful calculation and products based on insight into the basis of At the same time, the installation and post-testing also should be consistent with good design and manufacturers of communication, in accordance with appropriate adjustments to the specific circumstances in order to achieve full and fair use purposes.
ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve Three way ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com t
Classification and application of the composition of Control Valve
A control valve of the composition and classification
Control valve control valve is also called, is the main type of actuator, control unit regulating the output by receiving the control signal, using power-operated to change the fluid flow. Regulating valve and valves are generally composed of the implementing agencies. If you press it with the implementing agencies to use power, control valve can be divided into pneumatic, electric, hydraulic three kinds, namely, the source of compressed air-powered pneumatic control valve, to electric power source for electric control valve in order to liquid medium (eg oil) pressure-powered electric hydraulic control valve addition, according to their functions and features points, as well as solenoid valves, electronic, intelligent, fieldbus-type regulating valve. Many types of valve products, the structure is also diverse, but also continuously updated and changes. Generally speaking valve is a common, either with the pneumatic actuator match, but also with electric actuators, or other implementing agencies match.
The choice of two types of control valve
2.1 The control valve of the valve type selection valve option is to control valve selection of the most important aspects.
Many types of valve body, often there are through single-seat, through two-seater, angular, diaphragm, small flow, three-, eccentric rotation, butterfly, sleeve type, spherical, etc. 10. In selecting the valve prior to the media of the control process, process conditions and parameters to make a careful analysis, to collect enough data to understand the system requirements on the control valve, according to the data collected to determine the type of valve to be used. Specific options are available from the following aspects:
(1) Plug the structure mainly based on the selected shape of the flow characteristics and to consider factors such as unbalanced force.
(2) The wear resistance when the fluid medium that contain high concentrations of abrasive particles in suspension, the valve core, valve seat will be closed joints every serious friction. Therefore, the valve flow path should be smooth, Valve's internal materials to be hard.
(3) anti-corrosion due to corrosive media, in the regulatory function to meet the circumstances, as we choose simple valve.
(4) medium temperature and pressure when the medium temperature and pressure variation in high and when the valve core and valve seat should use the material by the temperature and pressure changes in the small valve.
(5) to prevent flashing and flashing and cavitation cavitation produced only in liquid medium. In the actual production process, the flashing and cavitation not only affect the calculation of flow coefficient, but also the formation of vibration and noise, shorten the life of the valve, so the choice should be to prevent the valve produces flash valve and cavitation .
2.2 The selection of the implementing agencies regulating valve
2.2.1 consideration of output force
No matter what type of executive body, the output power are used to overcome the load effective (mainly refers to the unbalanced force and unbalanced moment together with friction, sealing force, gravity force and other relevant role). Therefore, in order to control valve to work, with executive body used to be able to generate sufficient output force to overcome resistance and ensure a high degree of sealing and the valve opening.
For the double-acting pneumatic, hydraulic, electric actuator, generally do not reset spring. The size of the force direction has nothing to do with its operation, therefore, selecting executing agencies is the key to understand the maximum output power and the motor rotational torque. For single role of the pneumatic actuator, the output force and the opening of the valve, regulating valve on the emergence of the force will also affect the motion characteristics, thus requiring the entire range of control valve opening to establish the force balance.
2.2.2 Determination of types of the implementing agencies
Output force of the implementing agencies to determine, based on the use of environmental requirements, process, select the appropriate enforcement agency. For the scene, where explosion-proof requirements, should use pneumatic actuator, and the junction box for the explosion-proof type electric actuator is not an option. If there is no explosion-proof requirements, pneumatic and electric actuator can be selected, but energy-saving considerations, should try to use electric actuator. For the hydraulic implementing agency, its use than pneumatic, electric actuator broad, but with adjustable high precision, speed and smooth movement characteristics, therefore, in some cases, in order to achieve better conditioning results, we must use hydraulic implementing agencies, such as power plants and transparent machine speed regulation, the refinery's catalytic cracking unit reactor temperature adjustment control.
3 mode of action of regulating valve selection
Mode of action of control valve selection of pneumatic actuator only when they left, their mode of action through the pros and cons of the role of implementing agencies and valve combination of positive and negative role in the formation. There are four kinds of combination that is precisely (gas off type), the pros and cons (gas open type), anyway (gas open type), anti-anti-(gas off type), through the formation of these four combined mode of action of a gas control valve Open off two kinds of gas. For the choice of mode of action of control valve, the main three-pronged approach to consider: a) process production safety; b) characteristics of the medium; c) to ensure product quality, minimize economic losses.
4 regulating valve flow characteristics of the choice of
Regulating valve flow characteristic refers to the medium flowing through the valve flow and the relative displacement (relative valve opening) the relationship between the ideal flow characteristics are mainly straight lines, such as percentage (right number), a parabola, and quick to open, etc. four kinds of . The ideal flow characteristics of commonly used only a straight line, such as percentage (right number), quick to open three kinds. Parabolic flow characteristic between the percentage of straight lines and so on between the percentage of the general features can be used to replace the other, while the quick opening feature is mainly used for two-conditioning and process control, so control valve characteristics of choice is a straight line and the percentage of flow characteristics such as choice.
The choice of control valve flow characteristic through theoretical calculations, but the methods and equations used are very complex. At present, many with experience of the criteria, specifically from the following aspects to consider: ① from the conditioning system regulating the quality of analysis and selection; ② be considered from the process piping; ③ load change from the situation analysis.
Choose a good control valve flow characteristics, we can determine the flow characteristics according to their shape and structure of the valve spool, but like the diaphragm valves, butterfly valves, etc., because of their structural characteristics, it is impossible to change the spool of the surface shape to achieve the the required flow characteristics, when, through a change in the valve positioner with feedback cam profile to achieve.
5, the choice of regulating valve diameter
Valve caliber selection and identify key capability that is based on the flow valve Cv. Instrument in a variety of engineering design and selection, we need to calculate Cv regulating valves, and provides control valve design specifications. The Cv calculated from the control valve to the valve diameter to be determined, subject to the following steps:
1) Calculate the flow rate determination. The existing production capacity, equipment, load and medium situation, we decided the calculation flow Qmax and Qmin.
2) The valves before and after the determination of pressure. According to the selected valve flow characteristics and system characteristics of the selected S (drag coefficient), and then determining the calculation of pressure.
3) The calculation of Cv. According to the regulation of the media choose the right formula and charts, obtained Cmax and Cmin.
4) The selection of Cv. According to Cmax, in the standard series of products chosen, select> Cmax and its closest one C.
5) regulating valve opening checking. Generally require maximum computing flow of the opening ≯ 90%, the minimum calculated flow of the opening ≮ 10%.
6) control valve with adjustable ratio of the actual checking. Generally require more than the actual adjustable ≮ 10.
7) The seat diameter and the determination of the nominal diameter. Verified suitable, according to C determined.
6 Conclusion
The choice of regulating valve is a very painstaking work, not only a solid professional theoretical knowledge, but also has rich practical experience. Is well chosen not only helps to balance control loop tuning of PID parameters, so parameters were adjusted to get better control effect, also control valve life has increased considerably. Regulating valve should be selected according to local conditions, not set in stone, we must constantly sum up the process of practice and innovation, in particular with the mechanical and electrical integration technologies, computers and digital information technology, control valve structure and function has become better, more comprehensive, for the selection of control valve provides a great convenience.
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Control valve control valve is also called, is the main type of actuator, control unit regulating the output by receiving the control signal, using power-operated to change the fluid flow. Regulating valve and valves are generally composed of the implementing agencies. If you press it with the implementing agencies to use power, control valve can be divided into pneumatic, electric, hydraulic three kinds, namely, the source of compressed air-powered pneumatic control valve, to electric power source for electric control valve in order to liquid medium (eg oil) pressure-powered electric hydraulic control valve addition, according to their functions and features points, as well as solenoid valves, electronic, intelligent, fieldbus-type regulating valve. Many types of valve products, the structure is also diverse, but also continuously updated and changes. Generally speaking valve is a common, either with the pneumatic actuator match, but also with electric actuators, or other implementing agencies match.
The choice of two types of control valve
2.1 The control valve of the valve type selection valve option is to control valve selection of the most important aspects.
Many types of valve body, often there are through single-seat, through two-seater, angular, diaphragm, small flow, three-, eccentric rotation, butterfly, sleeve type, spherical, etc. 10. In selecting the valve prior to the media of the control process, process conditions and parameters to make a careful analysis, to collect enough data to understand the system requirements on the control valve, according to the data collected to determine the type of valve to be used. Specific options are available from the following aspects:
(1) Plug the structure mainly based on the selected shape of the flow characteristics and to consider factors such as unbalanced force.
(2) The wear resistance when the fluid medium that contain high concentrations of abrasive particles in suspension, the valve core, valve seat will be closed joints every serious friction. Therefore, the valve flow path should be smooth, Valve's internal materials to be hard.
(3) anti-corrosion due to corrosive media, in the regulatory function to meet the circumstances, as we choose simple valve.
(4) medium temperature and pressure when the medium temperature and pressure variation in high and when the valve core and valve seat should use the material by the temperature and pressure changes in the small valve.
(5) to prevent flashing and flashing and cavitation cavitation produced only in liquid medium. In the actual production process, the flashing and cavitation not only affect the calculation of flow coefficient, but also the formation of vibration and noise, shorten the life of the valve, so the choice should be to prevent the valve produces flash valve and cavitation .
2.2 The selection of the implementing agencies regulating valve
2.2.1 consideration of output force
No matter what type of executive body, the output power are used to overcome the load effective (mainly refers to the unbalanced force and unbalanced moment together with friction, sealing force, gravity force and other relevant role). Therefore, in order to control valve to work, with executive body used to be able to generate sufficient output force to overcome resistance and ensure a high degree of sealing and the valve opening.
For the double-acting pneumatic, hydraulic, electric actuator, generally do not reset spring. The size of the force direction has nothing to do with its operation, therefore, selecting executing agencies is the key to understand the maximum output power and the motor rotational torque. For single role of the pneumatic actuator, the output force and the opening of the valve, regulating valve on the emergence of the force will also affect the motion characteristics, thus requiring the entire range of control valve opening to establish the force balance.
2.2.2 Determination of types of the implementing agencies
Output force of the implementing agencies to determine, based on the use of environmental requirements, process, select the appropriate enforcement agency. For the scene, where explosion-proof requirements, should use pneumatic actuator, and the junction box for the explosion-proof type electric actuator is not an option. If there is no explosion-proof requirements, pneumatic and electric actuator can be selected, but energy-saving considerations, should try to use electric actuator. For the hydraulic implementing agency, its use than pneumatic, electric actuator broad, but with adjustable high precision, speed and smooth movement characteristics, therefore, in some cases, in order to achieve better conditioning results, we must use hydraulic implementing agencies, such as power plants and transparent machine speed regulation, the refinery's catalytic cracking unit reactor temperature adjustment control.
3 mode of action of regulating valve selection
Mode of action of control valve selection of pneumatic actuator only when they left, their mode of action through the pros and cons of the role of implementing agencies and valve combination of positive and negative role in the formation. There are four kinds of combination that is precisely (gas off type), the pros and cons (gas open type), anyway (gas open type), anti-anti-(gas off type), through the formation of these four combined mode of action of a gas control valve Open off two kinds of gas. For the choice of mode of action of control valve, the main three-pronged approach to consider: a) process production safety; b) characteristics of the medium; c) to ensure product quality, minimize economic losses.
4 regulating valve flow characteristics of the choice of
Regulating valve flow characteristic refers to the medium flowing through the valve flow and the relative displacement (relative valve opening) the relationship between the ideal flow characteristics are mainly straight lines, such as percentage (right number), a parabola, and quick to open, etc. four kinds of . The ideal flow characteristics of commonly used only a straight line, such as percentage (right number), quick to open three kinds. Parabolic flow characteristic between the percentage of straight lines and so on between the percentage of the general features can be used to replace the other, while the quick opening feature is mainly used for two-conditioning and process control, so control valve characteristics of choice is a straight line and the percentage of flow characteristics such as choice.
The choice of control valve flow characteristic through theoretical calculations, but the methods and equations used are very complex. At present, many with experience of the criteria, specifically from the following aspects to consider: ① from the conditioning system regulating the quality of analysis and selection; ② be considered from the process piping; ③ load change from the situation analysis.
Choose a good control valve flow characteristics, we can determine the flow characteristics according to their shape and structure of the valve spool, but like the diaphragm valves, butterfly valves, etc., because of their structural characteristics, it is impossible to change the spool of the surface shape to achieve the the required flow characteristics, when, through a change in the valve positioner with feedback cam profile to achieve.
5, the choice of regulating valve diameter
Valve caliber selection and identify key capability that is based on the flow valve Cv. Instrument in a variety of engineering design and selection, we need to calculate Cv regulating valves, and provides control valve design specifications. The Cv calculated from the control valve to the valve diameter to be determined, subject to the following steps:
1) Calculate the flow rate determination. The existing production capacity, equipment, load and medium situation, we decided the calculation flow Qmax and Qmin.
2) The valves before and after the determination of pressure. According to the selected valve flow characteristics and system characteristics of the selected S (drag coefficient), and then determining the calculation of pressure.
3) The calculation of Cv. According to the regulation of the media choose the right formula and charts, obtained Cmax and Cmin.
4) The selection of Cv. According to Cmax, in the standard series of products chosen, select> Cmax and its closest one C.
5) regulating valve opening checking. Generally require maximum computing flow of the opening ≯ 90%, the minimum calculated flow of the opening ≮ 10%.
6) control valve with adjustable ratio of the actual checking. Generally require more than the actual adjustable ≮ 10.
7) The seat diameter and the determination of the nominal diameter. Verified suitable, according to C determined.
6 Conclusion
The choice of regulating valve is a very painstaking work, not only a solid professional theoretical knowledge, but also has rich practical experience. Is well chosen not only helps to balance control loop tuning of PID parameters, so parameters were adjusted to get better control effect, also control valve life has increased considerably. Regulating valve should be selected according to local conditions, not set in stone, we must constantly sum up the process of practice and innovation, in particular with the mechanical and electrical integration technologies, computers and digital information technology, control valve structure and function has become better, more comprehensive, for the selection of control valve provides a great convenience.
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The average family used to buy Valve
When you purchase your visual valve, the surface should have no trachoma; plating the surface should be shiny uniform, to watch for peeling, cracking, burning, Lo the end of peeling, dark spots and obvious defects such as pits; spraying the surface of organizations should be detailed, smooth and uniform, not a stream linked to defects such as exposed at the end.
Civil valves commonly used in the current average family generally have gate valve, ball valve, triangle valve and other forms, usually iron or copper.
As the mechanical properties of copper alloys is good, with easy to rust, corrosion resistance strong advantages, it has gradually replaced the valve copper valve steel. Triangle valve basically have adopted the surface plating, and its role not only to control the flow of media channels, but also play a decorative role. Triangle valve normally connecting pipes and water hoses for Tap, Toilet water use, there are connecting pipes and water hoses for the water heater.
Gate the basic connections for the pipes and water meters.
Valve is used to connect pipes and water heaters.
As the ball valve open and close easily than the current pipeline and meter connections are also most of the use of ball valves.
Civil valves buy:
Should be based on the user's different requirements of different types of commercial valve selection:
1. When you purchase your visual valve, the surface should have no trachoma; plating the surface should be shiny uniform, to watch for peeling, cracking, burning, Lo the end of peeling, dark spots and obvious defects such as pits; spraying the surface of the Organization should dense, smooth and uniform, not a stream linked to defects such as exposed at the end. These deficiencies will directly affect the life of the valve.
2. Valve with the pipe connection pipe thread, and in choosing whether or dent the surface when the visual thread, broken teeth and other obvious defects, with particular attention to the pipe thread to connect pieces of rotating together with the effective length will affect the seal of the reliability, should pay attention to when purchasing the effective length of the pipe thread. General DN15 effective length of cylindrical pipe thread in the 10mm or so.
3. Gate valve, ball valve, or in general in their marked nominal pressure on the handle to purchase when the need to choose according to their own.
4. The replacement of existing gate valve or ball valve, it is necessary to ascertain the length of its structure so that can not be installed after purchase.
5. Triangular valves are female pipe thread and external thread two kinds, based on the need to purchase; would also like to note that currently on the market some of the triangular zinc alloy valves, the valve price is lower than the average product, But easy to fracture caused by corrosion.
Should be in a regular building materials stores, supermarkets, shopping, so that can better guarantee product quality. ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com o
Civil valves commonly used in the current average family generally have gate valve, ball valve, triangle valve and other forms, usually iron or copper.
As the mechanical properties of copper alloys is good, with easy to rust, corrosion resistance strong advantages, it has gradually replaced the valve copper valve steel. Triangle valve basically have adopted the surface plating, and its role not only to control the flow of media channels, but also play a decorative role. Triangle valve normally connecting pipes and water hoses for Tap, Toilet water use, there are connecting pipes and water hoses for the water heater.
Gate the basic connections for the pipes and water meters.
Valve is used to connect pipes and water heaters.
As the ball valve open and close easily than the current pipeline and meter connections are also most of the use of ball valves.
Civil valves buy:
Should be based on the user's different requirements of different types of commercial valve selection:
1. When you purchase your visual valve, the surface should have no trachoma; plating the surface should be shiny uniform, to watch for peeling, cracking, burning, Lo the end of peeling, dark spots and obvious defects such as pits; spraying the surface of the Organization should dense, smooth and uniform, not a stream linked to defects such as exposed at the end. These deficiencies will directly affect the life of the valve.
2. Valve with the pipe connection pipe thread, and in choosing whether or dent the surface when the visual thread, broken teeth and other obvious defects, with particular attention to the pipe thread to connect pieces of rotating together with the effective length will affect the seal of the reliability, should pay attention to when purchasing the effective length of the pipe thread. General DN15 effective length of cylindrical pipe thread in the 10mm or so.
3. Gate valve, ball valve, or in general in their marked nominal pressure on the handle to purchase when the need to choose according to their own.
4. The replacement of existing gate valve or ball valve, it is necessary to ascertain the length of its structure so that can not be installed after purchase.
5. Triangular valves are female pipe thread and external thread two kinds, based on the need to purchase; would also like to note that currently on the market some of the triangular zinc alloy valves, the valve price is lower than the average product, But easy to fracture caused by corrosion.
Should be in a regular building materials stores, supermarkets, shopping, so that can better guarantee product quality. ball valve Trunnion Mounted Ball Valve Floating Ball Valve Top Entry Ball Valve ball valve V Type Ball Valve
We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com o
Needle valve material selection
Under normal circumstances, needle valve materials shall be in accordance with its parameters and properties of the materials selected in accordance with this standard and shall comply with the relevant product standard requirements. Can also use the performance of not less than specified in this standard or for a contract the two sides agreed to purchase other materials.
The exceptional circumstances, the technical requirements of needle valve are as follows:
1. Gray cast iron needle valve
For the nominal pressure pN ≤ 1.0MPa, a temperature of -10 ~ 200 ℃ of water, steam, air, gas and oil and other media, gray cast-iron valves, the main part materials selected according to Table 1.
2. Malleable iron needle valve
For the nominal pressure pN ≤ 2.5MPa, a temperature of -30 ~ 300 ℃ of water, steam, air and oil and other media malleable iron valves, the main part materials selected according to Table 2.
3. Ductile iron needle valve
For the nominal pressure pN ≤ 4.0MPa, a temperature of -30 ~ 350 ℃ of water, steam, air and oil and other media, ductile iron system of valves, the main part materials selected according to Table 3.
4. Copper alloy needle valve
PN pN ≤ 2.5MPa for water, sea water, oxygen, air, oils and other media, as well as the temperature of -40 ~ 250 ℃ steam medium copper alloy valves, the main part materials selected according to Table 4.
5. Carbon steel needle valve
For the nominal pressure pN ≤ 32.0MPa, a temperature of -30 ~ 450 ℃ of water, steam, air, hydrogen, ammonia, nitrogen and petroleum products such as medium carbon steel valves, the main part materials selected according to Table 5.
6. High temperature steel needle valve
For the nominal pressure pN ≤ 16.0MPa, the temperature is less than or equal to 550 ℃ steam and petroleum products such as media, high-temperature steel valves, the main part materials selected according to Table 6.
7. Cryogenic steel needle valve
For the nominal pressure pN ≤ 6.4MPa, the temperature is higher than or equal to -196 ℃ ethylene, propylene, liquefied natural gas and liquid nitrogen cryogenic medium such as steel valves, the main part materials selected according to Table 7.
8. Stainless acid-proof steel needle valve
For the nominal pressure pN ≤ 6.4MPa, temperature is less than or equal to 200 ℃ of nitric acid, acetic acid and other media, stainless steel valves, the main part materials selected according to Table 8.
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The exceptional circumstances, the technical requirements of needle valve are as follows:
1. Gray cast iron needle valve
For the nominal pressure pN ≤ 1.0MPa, a temperature of -10 ~ 200 ℃ of water, steam, air, gas and oil and other media, gray cast-iron valves, the main part materials selected according to Table 1.
2. Malleable iron needle valve
For the nominal pressure pN ≤ 2.5MPa, a temperature of -30 ~ 300 ℃ of water, steam, air and oil and other media malleable iron valves, the main part materials selected according to Table 2.
3. Ductile iron needle valve
For the nominal pressure pN ≤ 4.0MPa, a temperature of -30 ~ 350 ℃ of water, steam, air and oil and other media, ductile iron system of valves, the main part materials selected according to Table 3.
4. Copper alloy needle valve
PN pN ≤ 2.5MPa for water, sea water, oxygen, air, oils and other media, as well as the temperature of -40 ~ 250 ℃ steam medium copper alloy valves, the main part materials selected according to Table 4.
5. Carbon steel needle valve
For the nominal pressure pN ≤ 32.0MPa, a temperature of -30 ~ 450 ℃ of water, steam, air, hydrogen, ammonia, nitrogen and petroleum products such as medium carbon steel valves, the main part materials selected according to Table 5.
6. High temperature steel needle valve
For the nominal pressure pN ≤ 16.0MPa, the temperature is less than or equal to 550 ℃ steam and petroleum products such as media, high-temperature steel valves, the main part materials selected according to Table 6.
7. Cryogenic steel needle valve
For the nominal pressure pN ≤ 6.4MPa, the temperature is higher than or equal to -196 ℃ ethylene, propylene, liquefied natural gas and liquid nitrogen cryogenic medium such as steel valves, the main part materials selected according to Table 7.
8. Stainless acid-proof steel needle valve
For the nominal pressure pN ≤ 6.4MPa, temperature is less than or equal to 200 ℃ of nitric acid, acetic acid and other media, stainless steel valves, the main part materials selected according to Table 8.
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The correct choice based primarily on the valve electric device
Valve electric device is programmed to achieve the valve, self-control and remote control can not be a lack of equipment, the process of its movement can be stroke, torque, or to control the size of the axial thrust. As the valve electric device operating characteristics and utilization depend on the type of valves, fittings and valves regulate the work or equipment at the location on the pipeline, therefore, correct choice of valve electric device, to prevent overload phenomenon (the work is delegated Moments higher than the control torque), is essential.
Typically, the correct choice of valve electric device based on the following:
Operation torque torque operation is to choose the most important parameters of valve electric device, electric device output torque valve operation should be the greatest moment of 1.2 ~ 1.5 times.
Operation Thrust host structure of the valve electric device, there are two: one is not configured thrust plate, direct output torque; the other is to configure thrust plate, the output torque of the stem nut through the thrust disk is converted to the output thrust.
Output shaft rotational number of laps valve electric actuator output shaft rotation the number of laps and the valve nominal diameter, stem pitch, thread the first few related, according to M = H / ZS calculated (M for the electrical installations should meet the total the number of rotating ring, H is the valve opening height, S for stem transmission thread pitch, Z for the valve stem thread first few).
Stem diameter and rotational ming for multi-pole valve, if the electrical device allows the maximum stem diameter of the valve stem can not be dispensed, it can not be assembled into electric valve. Therefore, the electrical device hollow output shaft diameter must be greater than specified under the valve stem diameter. On the part of the rotary valves, as well as multi-turn valves in the dark bar valves, although without considering the adoption of stem diameter, but should also take full account of the matching stem diameter and keyway size, so that work can be assembled .
Valves open and close the output speed if the speed too quickly, is easy to produce water hammer phenomenon. Should therefore be under different conditions of use, choose the appropriate hoist speed.
Valve electric device has its own special requirements that must be able to limit the torque or axial force. Valve Electric installations are usually limited torque Couplings. When the electrical device specification is established, its control torque also determined. Usually in a pre-determined period of time to run the motor is not overloaded. However, if the following conditions it may lead to overload: First, the supply voltage is low, are not required torque, the motor stops rotating; second is wrong it is set torque limit agencies, so that the torque is greater than stop , resulting in too big produces a continuous torque, the motor stops rotating; third intermittent use, the heat generated savings of more than the permitted temperature rise of the motor; Fourth, for some reason, body torque limit circuit failure, so that torque too large; 5 is to use the ambient temperature is too high, the relative decline in the motor heat capacity.
In the past to protect the motor way is to use fuses, overcurrent relays, thermal relays, thermostats, etc. However, these methods have their own advantages and disadvantages. This change of the electrical device load device, absolutely reliable protection method is not. Therefore, we must adopt various combinations, be summed up in two ways: First, changes in the input current to the motor to judge; second heat of the motor itself, to judge. These two methods, regardless of the kind of motor thermal capacity must take into account the given time margin.
Typically, the basic overload protection methods are: continuous operation of motor jog operation, or overload protection, using a thermostat; right motor locked rotor protection, thermal relay; pairs of short-circuit accident, following the use of fuse or over-current appliances.
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Typically, the correct choice of valve electric device based on the following:
Operation torque torque operation is to choose the most important parameters of valve electric device, electric device output torque valve operation should be the greatest moment of 1.2 ~ 1.5 times.
Operation Thrust host structure of the valve electric device, there are two: one is not configured thrust plate, direct output torque; the other is to configure thrust plate, the output torque of the stem nut through the thrust disk is converted to the output thrust.
Output shaft rotational number of laps valve electric actuator output shaft rotation the number of laps and the valve nominal diameter, stem pitch, thread the first few related, according to M = H / ZS calculated (M for the electrical installations should meet the total the number of rotating ring, H is the valve opening height, S for stem transmission thread pitch, Z for the valve stem thread first few).
Stem diameter and rotational ming for multi-pole valve, if the electrical device allows the maximum stem diameter of the valve stem can not be dispensed, it can not be assembled into electric valve. Therefore, the electrical device hollow output shaft diameter must be greater than specified under the valve stem diameter. On the part of the rotary valves, as well as multi-turn valves in the dark bar valves, although without considering the adoption of stem diameter, but should also take full account of the matching stem diameter and keyway size, so that work can be assembled .
Valves open and close the output speed if the speed too quickly, is easy to produce water hammer phenomenon. Should therefore be under different conditions of use, choose the appropriate hoist speed.
Valve electric device has its own special requirements that must be able to limit the torque or axial force. Valve Electric installations are usually limited torque Couplings. When the electrical device specification is established, its control torque also determined. Usually in a pre-determined period of time to run the motor is not overloaded. However, if the following conditions it may lead to overload: First, the supply voltage is low, are not required torque, the motor stops rotating; second is wrong it is set torque limit agencies, so that the torque is greater than stop , resulting in too big produces a continuous torque, the motor stops rotating; third intermittent use, the heat generated savings of more than the permitted temperature rise of the motor; Fourth, for some reason, body torque limit circuit failure, so that torque too large; 5 is to use the ambient temperature is too high, the relative decline in the motor heat capacity.
In the past to protect the motor way is to use fuses, overcurrent relays, thermal relays, thermostats, etc. However, these methods have their own advantages and disadvantages. This change of the electrical device load device, absolutely reliable protection method is not. Therefore, we must adopt various combinations, be summed up in two ways: First, changes in the input current to the motor to judge; second heat of the motor itself, to judge. These two methods, regardless of the kind of motor thermal capacity must take into account the given time margin.
Typically, the basic overload protection methods are: continuous operation of motor jog operation, or overload protection, using a thermostat; right motor locked rotor protection, thermal relay; pairs of short-circuit accident, following the use of fuse or over-current appliances.
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We can offer more Knife Gate Valve Information.If you need us according your spcification to produce the Knife Gate Valve .
Need, please e-mail to valve401@gmail.com
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