| 摘要 |
<p>PURPOSE:To facilitate insertion into an underground conduit where a triplex type power cable consisting of three twisted insulation wires is already constructed by pushing by composing an outer coating layer of plastic material having spiral grooves in the outer surface. CONSTITUTION:A core wire is composed of a tension member 2, and an optical fiber unit 3. The unit 3 is composed of a center reinforcement wire 31, and a plurality of optical fibers 32 provided on its circumference twisted with each other, and the outer circumference of the unit 3 is coated with a coating layer 1, where the coating layer 1 has a plurality of spiral grooves 11. A small diameter cable can be inserted along a triplex cable already constructed in a conduit along the direction of twist, so additive construction of the small diameter cable becomes easy.</p> |
