Intermediate Hydraulics Practice Test

When a pilot-operated check valve closes, the fluid in the line has inertia and can drive a sudden pressure surge known as hydraulic shock or water hammer. A decompression poppet provides a controlled relief path as the valve is closing, allowing the trapped fluid to decompress gradually. This dampens the closure event and prevents the sharp pressure spike that would otherwise occur, so the valve closes smoothly without shocking the system.

This tool isn’t about creating or maintaining low or high pressure or about preventing leakage; its purpose is to suppress the sudden pressure surge that comes with rapid valve closure.