摘要 |
An electric covering for a joint between a pair of electric cables, a device including such covering in elastically expanded condition on a rigid tubular support and electric cable joints including such covering. The covering includes at least two elastic sleeves of cross-linked polymeric material, a first radially inner sleeve at least partly of insulating material and a second radially outward sleeve. To permit the covering to be elastically expanded and encircling the rigid support for a long period of time, e.g. two years, the two sleeves have different mechanical properties and in particular, the material of the second sleeve has a residual deformation, which is applied by elongation over a period of time, which is less than the residual deformation, similarly applied, to the material of the first sleeve. The covering can also include a radially innermost stress grading, elastic third sleeve of cross-linked polymeric material, and the sleeves can be in contact and bonded together at their contacting surfaces.
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