Double walled pipe structures

摘要

An outer tube 12 contains an inner flow pipe 10, insulating material 16 being within the space therebetween, with longitudinally compressed elastomeric members 32 in the space between the tube and the pipe as the primary means for transferring longitudinal forces between them. The insulation 16 can be other than hollow alumina-silicate microspheres. Compression of each elastomeric member 32 is preferably by way of rigid plates on either side thereof which compress it. Bolts can be passed through bores in the plates and elastomeric member 32 and tightened thereby to compress the said member. The elastomeric member 32 is preferably in annular form and hence extends around the entire annular space between the tube and the pipe.