Pipe-line for cryogenic medium - has tubular coaxial insulating member with deformable plastics end walls sustaining internal vacuum

摘要

The transfer line component is for a thermal medium, particularly cryogenic, having a metal pipe section insulated under vacuum by a sealed casing having a tubular insulating member coaxial to the pipe and annular end walls forming thermal barriers. Each end wall (7,8) is formed by a buckling component of plastic, of thickness sufficient to sustain the insulating vacuum, and joined on the inside and outside respectively to pipe and member. The material used for joining the walls to the pipe has a mean modulus of elasticity less than 400hbar, and a ratio of fracture strength to modulus of elasticity of 0.01 or more. Its extension at fracture is greater than 4 per cent for the minimum temp. during distortion, and it has appropriate resilience at low temp.