"水锤压力" can be translated into English as "water hammer pressure" or "hydraulic shock pressure" (though "water hammer pressure" is more straightforward and commonly used in this context).
"Water hammer" refers to the sudden pressure surge or shock wave that occurs in a piping system when the flow of a fluid (usually water) is abruptly stopped or changed direction, due to factors like valve closure or pump shutdown. The pressure associated with this phenomenon is thus termed "water hammer pressure."