check valve(back pressure valve, swing valve, one-way valve): a valve that closes by fluid pressure to prevent return flow (Also called nonreturn valve),A check valve is a mechanical valve that only permits water flow in one direction. There must install check valve where don't allow fluid flow back such as compressor or pump outlet. | |||||||
For low pressure medium and nominal diameter If require pipe small water hammer or no water hammer, better select slow-close type swing check valve and low-close butterfly check valve. | |||||||
Types | Max. DN |
Max. PN | Temperature | Installation | Features and Application | sealing | resistance |
Vertical lift check valve |
50 | 6.4 | -29~550ºC | Horizontal pipe | Water, steam, oil | good | high |
Horizontal lift check valve |
50 | 6.4 | -29~551ºC | Horizontal / vertical pipe | Water, steam, oil | good | high |
Foot Valve bottom valve |
 |  |  | vertical pipe | Vertical pipe at Pump inlet and fluid flow from bottom to top. | ||
Swing Check Valves |
>2000mm | 42MPa | -196~800 ºC | Any direction (Horizontal, vertical, slant^) | Water, Seam, air, corrosive fluid, oil, food, medicines ect. Any fluid. | worse | low |
Butterfly Swing Check Valve |
>2000mm | 6.4MPa | -196~540ºC | Any difection (Horizontal, vertical, slant^) | low pressure big piping, suitable low speed flow medium | worse | low |
Diaphragm check valve |
>2000mm | 1.6MPa | -20~120ºC | tap water pipeline | Can relieve water hammer. |  |  |
Ball check valve |
200~1200mm | 42MPa | -196~540ºC | Horizontal / vertical pipe | Water, steam, oil, Nitric acid, urea and strong oxidizing medium,can relieve water hammer. full tube access. | good | low |
Valves are found in virtually every industrial process, including water and sewage processing, mining, power generation, processing of oil, gas and petroleum, food manufacturing, chemical and plastic manufacturing and many other fields.
People in developed nations use valves in their daily lives, including plumbing valves, such as taps for tap water, gas control valves on cookers, small valves fitted to washing machines and dishwashers, safety devices fitted to hot water systems, and poppet valves in car engines.
In nature there are valves, for example one-way valves in veins controlling the blood circulation, and heart valves controlling the flow of blood in the chambers of the heart and maintaining the correct pumping action.
Valves may be operated manually, either by a handle, lever, pedal or wheel. Valves may also be automatic, driven by changes in pressure, temperature, or flow. These changes may act upon a diaphragm or a piston which in turn activates the valve, examples of this type of valve found commonly are safety valves fitted to hot water systems or boilers.
More complex control systems using valves requiring automatic control based on an external input (i.e., regulating flow through a pipe to a changing set point) require an actuator. An actuator will stroke the valve depending on its input and set-up, allowing the valve to be positioned accurately, and allowing control over a variety of requirements.
Valves
Stop Valves, Ball Cock, Angle Valves, Gate Valves, Check Valves
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