CHECK VALVES

[visitor]

?CHECK VALVES USE?

 

[visitor]

check valves are very important when we deal with
pumps and fluids, hight velocity systems, flow must
be sufficient to keep the valve open fully otherwise
it will cause damages and high pressure drop.
location these valve in system is critical and it
must be not less than five pipe diameters from elbows.

 

[visitor]

now, cavitation can happen when we use this type
of valves especially when we use them with pumps
which can cause damage to pump .
these valves to my knowledge are normally designed
for installation in horizontal pipe runs or in vertical
lines where flow is up only.
i suggest to make sure the designed calculated with
safety factor to avoid that, maintain valve constanly,
make sure the pressure doesn`t drop and valve seat
maintain periodically.

 

[victim]

What is a recoil valve and can it help reduce water hammering?

 

[stanier]

I think your description "recoil" valve may be related to a translational type of check valve as manufactured byu Mokveld or Mannesmann Demag & others. It is a disc type check vale spring assisted where the disc travels on a central shaft in the direction opf flow. these valves are designed to close rapidly on loss of pressure. Thus the pump is protected from transients. In addition the spring keeps the disc seated until the pumps restart. Of course I'm guessing that is what recoil refers to. It may be a rubber duckbill type of valve as made by RED Valve.\b

 

[Wrokshop]

My comment may be for check valve application.
When pump (and associate pipeline) is not running or operating, related isolation /block valves shall be closed. There was crude oil spill incident due to the oil leaked through check valves. It was happen because of equilibrium pressure in the line during no flow. Check valve does not function or no meaning when there is no flow or no pressure drop.