Fully Welded Flanged Ball Valve

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 fully welded body uses welded joints to form the pressure-containing shell with fewer detachable body joints. Review shell inspection, end-connection welding procedures and the maintenance approach after installation. Body construction and pipeline end connections are separate design decisions.

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

Welded ends must suit pipe material, wall thickness and the construction procedure. Heat effects, protection of internal seals and post-weld cleanliness are important. Set welding parameters and inspection methods for the actual materials and joint.

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.