| 摘要 |
<p>The h.v. cable has a transposed or twisted wire core (1), inner conducting layer (2) for stress equalising, and extruded main insulation(3) typically of polyethylene. The outer conducting layer (4), similarly extruded, is made with longitudinal grooves(5) in its outer surface. Between the metallic armouring (7), which fits on the longitudinal ridges(6), and the grooves (5) an expandable filling material is inserted. This material swells with moisture to seal off any further moisture ingress. Typically, the material has a cellulose base.</p> |
