Understanding the best way to avoiding valve slam. 

check valve is a simple self-acting device used to prevent reverse flow in a pipeline.  When it comes to choosing the correct non-slam check valve, several factors need to be considered such as media type, temperature, pressure and flow rates.  Correct selection will ensure valve longevity and prevent wear and slam. 

What is check valve slam?

Check valve slam generally occurs following pump stop or failure event.   As the pump stops, gravity and reserve flow acts on the valve disc potentially resulting in slam.  As fluids are not compressible, it creates a pressure or shock wave, also known as water hammer.  The fluid continues to oscillate within the pipe until friction losses cause the wave to dissipate.   

non-slam-valve
Recoil Check Valve, DN80-DN1200, PN16, Single Door

Rattling pipes and equipment damage can result from slamming check valves.   Correct valve selection taking into consideration hydraulic conditions will avoid water hammer and valve slam. 

For product selection advice, you can get in touch with us on +44 (0) 1630 647200Heavy-Duty Recoil Check Valve from TT Flow, which is used to avoid valve slam.