Check valves prevent the hydraulic shock by design
By Sheila Kennedy, CMRP, Chemical Processing Contributing Editor
Water hammer can be so damaging to machinery and dangerous to human health that every effort should be taken to prevent the hazard. Also known as hydraulic shock, water hammer sounds like a mechanical noise and is sometimes perceived to be a valve slamming closed. In reality, it is a phenomenon that occurs in piping systems when fast-moving fluid instantly stops, or reverse flow begins. The sudden change in momentum or direction induces the hydraulic shock wave, creating what sounds like a loud bang.