TFL assembly for a dual diameter flow-line/riser system and flow- line/riser system for use with the assembly

摘要

A TFL assembly is disclosed for use in a dual diameter flow- line/riser system which includes a small diameter flow-line section and a large diameter riser section. The assembly comprises a pig fitting in the small diameter flow-line section and a pig catching tool fitting in the large diameter riser section. The pig catching tool comprises a central opening which is sealed off by the pig upon joining said pig and tool after entry of the pig from the small diameter flow-line section into the large diameter riser section.