Certification and inspection documents

Service conditions

A ball valve opens or closes the pipeline by rotating a ported ball. Port geometry, seats and stem sealing determine its operating behavior. Selection should consider differential pressure, fluid cleanliness and cycling duty together.

A trunnion-mounted arrangement supports the ball independently of the seats. Fluid loading is carried through the supports and seat system. Seat loading, operating torque and cavity-pressure management are important to operation and maintenance at changing differential pressures.

Construction and description

Match the operator to the valve load and site operating method. Manual operation needs accessible clearance. Frequent cycling or remote control also calls for assessment of output capability, duty and position feedback.

Service conditions

Flanged ends support piping interfaces and removal for service. Match flange standard, pressure designation, facing, gasket and fasteners, and check face-to-face length and pipe support to limit piping loads on the body.

Construction and description

Define fluid composition and continuous and start-stop operating conditions, then assess body, internals and seals as a combination. Particles, deposits and cleaning affect sealing surfaces and mechanisms; plan maintenance for the actual service.