| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat insulating pipe whose inner pipe is made out of a hard synthetic resin, which is easy to manufacture, excellent in quality, has a stable structure preventing heat insulating martial from being protruded or pulled out from its cut-ends, and also prevents the occurrence of dew condensation. SOLUTION: An inner pipe 1 is formed up by letting belt shaped material 1' made out of a hard synthetic resin in a semi-fused state, by wound up in a spiral form, and a heat insulating layer 2 is formed up by letting belt shaped heat insulating material 2' made out of a foamed polyethylene resin which is hardly bonded or difficult to be bonded over to the inner pipe 1 made out of a hard synthetic resin, by similarily wound up in a spiral form over the inner pipe 1, and concurrently, the inner and outer end parts themselves at the joint surface of a belt shaped heat insulating material part having been wound up in advance and a belt shaped heat insulating material part wound up later on, are mutually fused so as to be integrally bonded with each other 4 and 5, and furthermore, the occurrence of dew condensation is prevented by letting the surface of a heat insulating layer 2 be fully exposed, or covered with an outer tube made out of nonwoven fabric in order to absorb moisture. |
