Applied Research on Field Joint Technology of 3LPP Coating

摘要

Normally the maximum continuous in-service operating temperature of 3-layer polyethylene (3LPE) coating is not more than 70 ° C.In order to solve the problem of pipeline coating under temperatures higher than 80 ° C,especially for crude oil pipeline,a 3-layer polypropylene (3LPP) coating structure has been developed and applied in practice both domestically and abroad.However,at present time only one form of field joint coating based on polypropylene shrinkable tape is widely adopted for 3LPP coating.This paper will introduce the pioneering work of a new field joint technology based on solvent-free epoxy,viscoelastic and PE heat shrinkable tapes.Also discussed are the selection of new filed joint coating materials,the establishment and testing of the filed joint coating overall performance,and the application of this new field joint technology on the Chad crude oil pipeline project.