Valve Commissioning and Pre-Startup Testing Procedures

Valve commissioning before plant startup verifies that installed valves function correctly, meet performance specifications, and are properly configured for service. A systematic commissioning procedure reduces the risk of valve-related problems during startup and normal operation. Commissioning activities include pre-installation inspection, stroke testing, calibration, leak testing, and documentation. Thorough commissioning is particularly important for safety-critical valves, control valves, and valves in hazardous service.

Pre-Installation Inspection

Before valve installation, each valve should be inspected to verify it matches the purchase specification (correct size, pressure class, material, end connection, body and trim material, actuator type). Documentation review should confirm the valve data sheet, manufacturer's test reports, material certifications, and NDE reports are complete and acceptable. Physical inspection should check for shipping damage, cleanliness, proper packing protection (bore plugs installed), and correct orientation markings. Actuated valves should be operated manually to verify free movement, correct range of motion, and absence of binding.

• Nameplate verification: confirm size, pressure class, material match specification

• Documentation review: test reports, material certs, NDE records

• Physical inspection: no shipping damage, bore plugs present, marking correct

• Manual stroke: verify valve moves freely through full range of travel

• Limit switch check: verify open and closed position switches trip correctly

Stroke Testing and Calibration

Actuated valves must be stroke-tested in the installed configuration to verify proper response to control signals, correct travel limits, and fail-safe positioning. For pneumatic control valves, the positioner input signal range (4-20 mA), output pressure range, and actuator stroke must be calibrated per manufacturer procedures and the instrument data sheet. Zero, span, and characterization should be verified. For on-off valves (ESD and block valves), full open and full closed stroking should be confirmed, and limit switch positions verified to send correct position feedback to the control system.

Hydrostatic and Leak Testing

Installed valves may require post-installation leak testing per project specifications. Shell (body) leak testing confirms the pressure integrity of the installed valve and flange connections. Seat leak testing verifies acceptable shutoff performance. Testing pressure and acceptance criteria must match the applicable standard (API 598, ASME B16.34) and project specifications. Safety valves (PRVs and PSVs) must be verified for correct set pressure by certified test facilities and tagged with tamper-evident seals. Documentation of all commissioning test results must be retained as part of the plant's as-built records.