Abstract: This article takes the actual engineering project of a large refinery in Guangdong Province for example, and analyzes the concept of water hammer in engineering mentioned in traditional literature. It is believed that the concept of water hammer in the current literature is vague and imprecise, and some amendments are proposed to the traditional concept of water hammer. This article analyzes in detail the causes of valve-closed water hammer and pump-stopping hammer in UF backwash process based on the revised concept of water hammer and puts forward the corresponding solutions.

Key words: water hammer, valve-closed water hammer, pump-stopping water hammer