| 摘要 |
<p>PURPOSE:To inhibit firing from the breaking port of a power cable by forming the primary disaster preventive layer of a non-magnetic metallic tape having high strength and the secondary disaster preventive layer of a flame-retardant resin sheet having elasticity. CONSTITUTION:When a breaking point is generated in a power cable, internal pressure is applied to the metallic tape 21 of a primary disaster preventive layer 2 by discharged energy, but grounding energy is dispersed and absorbed by the high strength of the metallic tape 21. When grounding energy is considerably large, however, the metallic tape 21 is bursted from a coupling section under a non-sealing state before breaking and energy is discharged to the outside. The pressure of energy discharged is lowered by its own expansion and deformation by internal pressure in the internal layer 4 and external layer 5 of a secondary disaster preventive layer 3, thus absorbing energy. Oil leaking from the breaking point of the power cable 1 is confined in the internal layer 4 or external layer 5 of the secondary disaster preventive layer 3, and the danger of ignition is eliminated.</p> |
