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

Patent metadata

Field	Value
Publication number	US-10763010-B2
Application number	US-201816015688-A
Country	US
Kind code	B2
Filing date	Jun 22, 2018
Priority date	Sep 28, 2004
Publication date	Sep 1, 2020
Grant date	Sep 1, 2020

Abstract

Disclosed are cable types, including a type THHN cable, the cable types 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 material containing nylon or thermosetting resin. A silicone based pulling lubricant for said cable, or alternatively, erucamide or stearyl erucamide for small cable gauge wire, is incorporated, by alternate methods, with the resin material from which the outer sheath is extruded, and is effective to reduce the required pulling force between the formed cable and a conduit during installation.

First claim

That which is claimed:

1. A thermoplastic high heat-resistant nylon-coated (THHN) electrical cable having a reduced installation pulling force through a building passageway defined by a PVC conduit setup sized to accommodate the THHN electrical cable and having at least two 90° bends within the PVC conduit setup, the THHN electrical cable comprising:
at least one conductor capable of carrying an electrical current through the THEN electrical cable, wherein the conductor is formed at least in part from a metal; 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, contacting, and forming a coating for the insulating layer, wherein the outer layer comprises a solidified extrusion of a material mixture, the material mixture comprising:
a nylon material; and
a pulling lubricant mixed within at least a portion of the nylon material, wherein at least a portion of the pulling lubricant is present at an exterior surface of the sheath to reduce the amount of force required to pull the cable through the building passageway; and

wherein the outer layer is both resistant to heat, moisture, oil, and gasoline and provides the THHN electrical cable with the physical characteristic of requiring at least about 30% less force to pull the electrical cable through the building passageway compared to an amount of force required to pull a non-lubricated THEN electrical cable having an extruded sheath without the pulling lubricant mixed therein through the building passageway.

2. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 1 , wherein the pulling lubricant comprises a silicone oil.

3. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 1 , wherein the pulling lubricant comprises a high molecular weight silicone based pulling lubricant.

4. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 1 , wherein the pulling lubricant comprises a low molecular weight silicone based pulling lubricant.

5. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 1 , wherein the pulling lubricant comprises erucamide.

6. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 1 , wherein the at least one conductor comprises a plurality of grouped conductors.

7. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 1 , wherein the at least one conductor is a large gauge conductor.

8. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 7 , wherein the at least one conductor comprises an AWG 4/0 conductor.

9. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 1 , wherein the sheath is formed with geometrical characteristics that are not altered relative to the geometrical characteristics of the extruded sheath of the non-lubricated THEN cable.

10. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 9 , wherein the sheath has a round profile.

11. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 1 , wherein the THEN electrical cable is rated for use in dry locations at temperatures not to exceed 90° C.

12. The thermoplastic high heat-resistant nylon-coated (THEN) electrical cable of claim 1 , wherein the THEN electrical cable is rated to carry current at voltages not to exceed 600 Volts.

13. A thermoplastic high heat-resistant nylon-coated (THEN) electrical cable having a reduced installation pulling force through a building passageway defined by a PVC conduit setup sized to accommodate the THEN electrical cable and having at least two 90° bends within the PVC conduit setup, the THEN electrical cable comprising:
at least one conductor capable of carrying an electrical current through the THEN electrical cable, wherein the conductor is formed at least in part from a metal; 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, contacting, and forming a coating for the insulating layer, wherein the outer layer comprises a solidified extrusion of a material mixture, the material mixture comprising:
a nylon material; and
a pulling lubricant mixed within at least a portion of the nylon material, wherein at least a portion of the pulling lubricant is present at an exterior surface of the sheath to reduce the amount of force required to pull the cable through the building passageway; and

wherein the outer layer is both resistant to heat, moisture, oil, and gasoline and provides the THHN electrical cable with the physical characteristic of requiring at least about 50% less force to pull the electrical cable through the building passageway compared to an amount of force required to pull a non-lubricated THHN electrical cable having an extruded sheath without the pulling lubricant mixed therein through the building passageway.

14. The thermoplastic high heat-resistant nylon-coated (THHN) electrical cable of claim 13 , wherein the sheath is formed with geometrical characteristics that are not altered relative to the geometrical characteristics of the extruded sheath of the non-lubricated THHN cable.

15. The thermoplastic high heat-resistant nylon-coated (THHN) electrical cable of claim 14 , wherein the sheath has a round profile.

16. A non-metallic sheathed (NM-B) electrical cable having a reduced installation pulling force through a building passageway extending through throughholes drilled at a 15 degree angle through a broadface of each of four 2″×4″ wood blocks, wherein the wood blocks are linearly spaced apart from one another and are offset such that a centerline of each of the throughholes is offset by 10″ relative to one another, the NM-B electrical cable comprising:
a conductor core comprising at least two insulated metal conductors capable of carrying an electrical current through the NM-B electrical cable, wherein the conductor is formed at least in part from metal; and
a sheath for protecting the conductor core, wherein the sheath comprises a solidified extrusion of a material mixture, the material mixture comprising:
an insulating material providing electrical insulation to the conductor core, wherein the insulating material comprises polyvinyl chloride; and
a pulling lubricant mixed with at least a portion of the insulating material, wherein at least a portion of the pulling lubricant is present at an exterior surface of the sheath to reduce the amount of force required to pull the cable through the building passageway; and

wherein the sheath provides the NM-B electrical cable with the physical characteristic of requiring at least about 30% less force to pull the electrical cable through the building passageway compared to an amount of force required to pull a non-lubricated NM-B electrical cable having an extruded PVC jacket without the pulling lubricant mixed therein through the building passageway.

17. The NM-B electrical cable of claim 16 , wherein the pulling lubricant comprises one of erucamide or oleamide.

18. The NM-B electrical cable of claim 17 , wherein the pulling lubric

Assignees

• Southwire Co Llc

Inventors

• Sasse Philip
• Chambers Terry
• Kummer Randy D
• Armstrong John
• Reece David
• Lam Hai

Classifications

• H01B13/24 Primary

  by extrusion {(extrusion of cables with plastic material in general B29C48/15)} · CPC title

• C08K5/54

  Silicon-containing compounds {(C08K5/0091 takes precedence)} · CPC title

• H01B7/02

  Disposition of insulation · CPC title

• H01B7/292

  using material resistant to heat · CPC title

• H01B3/22

  hydrocarbons · CPC title