Patent ID: 8616918

Claim:
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; wherein the so-manufactured THHN cable has the characteristic that an average amount of force required to install said cable through an arrangement of conduit is less than the average amount of force required to install a cable of the same cable type and size, that has substantially no external lubrication at said exterior portion, through said arrangement of conduit, the arrangement of conduit being defined as PVC conduit that is sized to accommodate said cable having an initial 10 foot straight section of conduit, followed by a first 90Â° bend having a left-orientation, followed by a second 90Â° bend having a right-orientation, followed by a 30 foot straight section of conduit, followed by a third 90Â° bend having a right-orientation, followed by a 5 foot straight section of conduit, followed by a fourth 90Â° bend having a right-orientation, followed by a 10 foot straight section of conduit.