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AssigneeSouthwire Company
InventorsTerry Chambers, Randy D. Kummer, John Armstrong, Philip Sasse, David Reece, Hai Lam
Estimating the term…
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.
In a process for manufacturing a THHN cable of the type comprising a conductor and protective sheath surrounding said conductor, in which the protective sheath has at least its exterior portion formed of nylon, the improvement in which a pulling lubricant is introduced in said material during the manufacture of the cable, in a concentration sufficient to either permeate throughout, or migrate through, said exterior portion of the sheath to be available at the exterior surface of said protective sheath when said cable is pulled along an installation surface through inclined building passageways, said concentration sufficient to reduce the required installation pulling force for installation of the THHN cable through said building passageways;
An improved process of manufacturing a finished THHN cable of the type comprising at least a central conductor and a surrounding sheath of nylon material defining the exterior surface of the finished THHN cable, said process comprising:
Dependencies are inferred from the claim text.