Method of manufacturing electrical cable, and resulting product, with reduced required installation pulling force

摘要

Disclosed is type THHN cable having a reduced surface coefficient of friction, and the method of manufacture thereof, in which the central conductor core and insulating layer are surrounded by a nylon sheath. A high viscosity, high molecular weight silicone based pulling lubricant for THHN cable, or alternatively, erucamide or stearyl erucamide for small THHN gauge wire, is incorporated, by alternate methods, with the nylon material from which the outer sheath is extruded, and is effective to reduce the required pulling force on the cable during installation.

主权项

1. A thermoplastic high heat-resistant nylon-coated (THHN) electrical cable having reduced installation pulling force through a polyvinyl chloride (PVC) conduit setup, the THHN electrical cable comprising:
at least one conductor capable of carrying an electrical current through the THHN electrical cable, wherein the conductor is formed at least in part from copper; and, a sheath for protecting the conductor, wherein the sheath comprises:
an insulating layer surrounding the conductor and providing electrical insulation to the conductor, wherein the insulating layer is formed at least in part from extruded polyvinyl chloride (PVC); and,an outer layer surrounding the insulating layer, wherein the outer layer further comprises;
an extruded nylon component;a pulling lubricant incorporated in the extruded nylon component that aids in reducing the installation pulling force as the THHN electrical cable is pulled through a PVC conduit setup; and wherein,
the pulling lubricant is silicone based; andthe pulling lubricant is present in at least a portion of the outer layer at a concentration of between about 4% and about 14% by weight; and further wherein,the outer layer is both resistant to heat, moisture, oil and gasoline, and provides the THHN electrical cable with the physical characteristic of having an average coefficient of friction against an interior surface of a PVC conduit setup of less than about 0.25.