Double-walled pipe coupling - has one pipe expanded to enclose other, and has elastic seals sealing ring chamber between two pipes

摘要

A coupling (1) for double-walled pipes (2, 3), esp. vacuum insulated cryogenic fluid pipes, has the inner fluid line (8) of one pipe (2) expanded (at 10) at the coupling to enclose the outer shell (5) of the other pipe (3). Elastic seals (12, 18) seal each end of the ring chamber (11) formed between the two pipes at the coupling. The innermost seal (12) is gas-tight, at least in the direction towards the transported fluid. ADVANTAGE - Improved seal, preventing gas and water vapour entering the fluid line, for pipes at all inclinations.