| 摘要 |
A heat-shrinkable plastics cover, partic. for use over a gas or oil pipeline joint, comprises a rectangular sheet with a pair of tongues along each end edge and with electrical heating element coated with cross-linked polymer and located to cross at right angles the inherent shrink direction of the sheet so that it does not interfere with shrinking. The sheet pref. has a heat-sensitive cross-linkable bonding layer on one surface and on the inner surface of either one of the opposing tongues. The element pref.extends through the sheet and in an upper tongue on one end and a lower tongue on the other.
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