How valve hammer causes knocking in triplex pumps

This article investigates valve hammer as opposed to water hammer in triplex pumps, both of which produce knocking under certain distinctly different hydraulic operations. The occurrence of water hammer is reviewed and the development of valve hammer is discussed and documented. This work examines normal valve operation and abnormal operations at higher speeds where valve lag develops and valve hammer occurs. Valve hammer results in high impact at the instant of closure which produces a bang noise and can result in part peening and possible failure.