"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 increase in pressure in a piping system caused by the rapid change in flow velocity, often due to the sudden closure of a valve or the rapid stopping of a pump. The pressure surge resulting from this phenomenon is termed "water hammer pressure."