Summary of stainless steel check valve/classification/use
1, summary of stainless steel check valve stainless steel check valve is also known as reflux valve, non-return valve, back pressure valve, check valve.
Stainless steel check valve is to rely on the force created by the flow of the medium itself in the line of the automatic opening and closing, belongs to a kind of automatic valve.
Stainless steel check valve can be divided into lift check valve, stainless steel swing check valve, stainless steel disc type check valve and all kinds of stainless steel stainless steel stainless steel check valve check valve to the clamp can also be used to give the pressure could rise to more than the main system of auxiliary system supply piping.
Stainless steel check valve according to different materials, the pipeline can be applied to a variety of media.
Check valve installed in the pipeline, that is, to become a full line of fluid components, one of the valve opening and closing process will be affected by it in system is influenced by transient flow state;
On the other hand, the disc in closing feature and have hair effects on fluid flow state.
Working characteristics of the stainless steel check valve is the load change is big, small open-close frequency, one in closed or open, apply cycle is very long, and does not require moving parts movement.
But once again & other;
Switch & throughout;
Request, you must move the flexible, this is one of the more common mechanical movement is more demanding.
Because the stainless steel check valve in the most practical use, qualitatively determine for fast shut down, and at the instant of the check valve closed, medium is a direction, with the disc in closing, the medium from the rapid rate of maximum back down to zero, while the pressure rise rapidly, which produce the possible damage to pipeline system & other
Water hammer & throughout;
For more than one pump in parallel for high pressure pipeline system, the check valve water hammer problems become more prominent.
Water hammer is one of the pressure transient flow in the pipeline pressure wave, which is caused by the change of the fluid velocity in pressure piping pressure jump or fall rise of the hydraulic impact phenomenon.
Its physical reason is that the incompressibility of fluid, fluid motion inertia and elastic pipe combination results.
In order to prevent water hammer in pipeline risk, over the years, people in the design of the check valve, adopted some new structure, new material, the guarantee of the check valve is applicable for the performance at the same time, minimize the impact of the water hammer has achieved gratifying progress.
2, the classification of the stainless steel check valve.
Stainless steel swing check valve with the humble hinge institutions, there is also a disc freely like door on the tilt of the seat surface.
In order to ensure that each disc to seat the appropriate location, in valve design hinge agencies, so that the disc with enough space of a swing, and real, comprehensive, and the valve seat contact.
All disc can be made from metal, can be embedded in the metal on leather, rubber, or synthetic coverage, depending on the use of performance requirements.
Swing check valve in the fully open conditions, almost unimpeded fluid pressure, so the pressure drop across the valve is relatively small.
Stainless steel lift check valve disc is located in the body seat sealing surface.
In addition to this check valve can be freely valve movements, like the rest of the cut-off valve, fluid pressure from the valve seat sealing surface lift, medium return led to the disc back to seat, and cut off the flow.
According to the conditions of use, valve can be all-metal structure, it can also be embedded in disc shelves rubber mat or rubber ring form.
Like a cut-off valve, fluid through the lift check valve channel is narrow, so the lift check valve through the pressure drop than the swing check valves are bigger, and swing check valves are very few restrictions.
Butterfly check valve disc around a seat inside the pin shaft rotation of check valve.
Disc check valve has simple structure, can only be installed in horizontal pipe runs, poor sealing.
Shigeru letter a breakdown of the stainless steel check valve: stainless steel check valve stainless steel swing check valve lift check valve stainless steel wafer check valves 3, stainless steel stainless steel swing check valve check valve using stainless steel check valve is suitable for the pressure 1.
6 ~ 25 mpa / 2。
- 0 mpa working temperature
29 ~ + 550 ℃ in the petroleum, chemical, pharmaceutical, chemical fertilizer, power industry, such as the pipeline under various working conditions, suitable medium such as water, oil, steam, acid medium.
Stainless steel check valve used for pipeline system, its main role is to prevent the backflow medium, to prevent the pump and its pattern in reverse driving voltage, and the discharge of the containers within the medium.
The editorial by letter always fine alum valve co. , LTD