Cap

A butt-weld cap closes the end of a piping run with a permanent welded joint. It differs from a bolted blind flange and is not intended as a routine removable access closure. Selection should cover the pipe-end diameter and wall, material and fluid compatibility, end geometry and clearance, welding procedure, and inspection requirements. Any future cutting or removal requires safe isolation, depressurization, and control of trapped contents under the project procedure; the cap designation alone does not establish design conditions.