| 摘要 |
<p>An insulating tube is made by drawing a composite tube (16) comprising an inner tube (10) and an outer tube (14) defining an annular space therebetween, the annular space containing a compressible compacted particulate microporous insulation material (12), the outer tube (14) being made of a ductile material. The composite tube (16) is drawn through one or more dies (18) so as to reduce the diameter of the outer tube (14) to a predetermined diameter while the diameter of the inner tube (10) remains substantially constant and so as to further compress and compact the particulate microporous insulation material (12) and maintain it under compressive stress. Thereafter the ends of the composite tube (16) are trimmed. The inner tube (10) can be open at the ends thereof as the composite tube (16) is drawn through the one or more dies (18). <IMAGE></p> |
