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AssigneeSouthwire Company
InventorsRandy D. Kummer, David Reece, Hai Lam, Philip Sasse, John Armstrong, Terry Chambers
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 power cable of the type comprising a conductor and sheath surrounding said conductor, in which the sheath has at least its exterior portion formed of nylon material, an improvement in which a erucamide pulling lubricant is introduced in said material during the manufacture of the cable but prior to the formation of said sheath, and either permeates throughout, or migrates through, at least said exterior portion of the sheath to be available at the exterior surface of said sheath as said power cable is pulled along an installation surface through building passageways in rafters or joists or conduit bends, and in a concentration sufficient to reduce the required installation pulling force for installation of the cable through building passageways in rafters or joists or conduit bends.
An improved process of manufacturing a finished power cable assembly of the type comprising a central conductor and a surrounding sheath of at least one outer layer of nylon material defining the exterior surface of the finished cable, said process comprising:
An improved process of manufacturing a finished power cable of the type comprising a central conductor and a surrounding sheath, at least an outer portion of which is of nylon material, the process comprising introducing a erucamide pulling lubricant into the sheath prior to the completion of the manufacturing of the finished power cable of a concentration of between about 0.25% and 0.85%, by weight, to be available at the exterior surface of the sheath, and sufficient to reduce the required pulling force during the cable's installation through building passageways in rafters or joists or conduit bends.
In a power cable of the type comprising a conductor and a sheath surrounding said conductor, in which the sheath has at least its exterior portion formed of nylon material, an improvement in which a silicone based pulling lubricant, is introduced in said material during the manufacture of the cable but prior to the formation of said sheath, permeates throughout at least said exterior portion of the sheath to be available at the exterior surface of said sheath as said cable is pulled along an installation surface through building passageways in rafters or joists or conduit bends, and in a concentration sufficient to reduce the required installation pulling force for installation of said cable through building passageways in rafters or joists or conduit bends.
An improved process of manufacturing a finished power cable assembly of the type comprising a central conductor and a surrounding sheath of at least one outer layer of nylon material defining the exterior surface of the finished cable, said process comprising:
Dependencies are inferred from the claim text.