AN INSULATED FLUID DUCT

摘要

A duct section (2) comprises inner and outer pipes ( 4, 6) which define a space (8) between them. The space (8) is evacuated to insulate the inner pipe (4). The inner (pipe 4) comprises first and second inner pipe portions (14, 16) of which the first pipe (portion 4) includes a bellows (26) to accommodate differential expansion between the inner pipe (4) and the outer pipe (6). The inner pipe (4) is supported within the outer pipe (6) by support elements (34) which are secured to the inner pipe (4) and slidable with respect to the outer pipe (6). The support elements also support a radiation screen (54).