Stainless Steel Spring Check Valve (Threaded)

An in-line check valve allows fluid to pass in one direction only. Pressure in the flow direction lifts the spring-loaded poppet off its seat to open the passage; when flow stops or reverses, the spring and back pressure press the poppet onto its seat to close the line. This prevents the line from draining back when the pump stops and keeps reverse flow from damaging equipment.

It is used at pump outlets, in parallel pump and accumulator circuits, in the hydraulic circuits of ship steering systems, in fire pump sets, and in the dosing and transfer lines of chemical and food plants.

• The cracking pressure depends on spring selection; select a suitable spring for low-pressure lines.
• Body and seal materials must suit the fluid, and the connection thread (BSP / NPT) must match the standard used in the line.
• With contaminated fluid, particles entering the poppet seat compromise sealing; consider filtration upstream.

Installation note: Install the valve with the flow arrow on the body pointing in the flow direction of the line. A check valve installed backward closes the line completely.