TREA

Semi-foamed polyethylene molding tape

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Information

  • Patent Grant
  • 4759973
  • Patent Number
    4,759,973
  • Date Filed
    Friday, December 12, 1986
    38 years ago
  • Date Issued
    Tuesday, July 26, 1988
    36 years ago
Information
Abstract
A semi-foamed polyethylene tape for use in the molding of foamed jacket pethylene cables. After tumble mixing low density foaming polyethylene, ethylene vinyl acetate co-polymer and polyethylene color concentrate, the tape is extruded on a thermoplastic extruder having a maddox mixing screw that effectively mixes polyethylene compounds and a slot die with a suitable opening dimension. The tape is then quenched. By controlling manufacturing variables the tape is foamed to 40% to 50% of its maximum. The tape is then foamed to 100% maximum during the manufacturing of a cable assembly.
Description
Claims
  • 1. A molding tape for use in providing insulated covering for electrical hardware comprising:
  • substantially 100.00 parts of low density foaming polyethylene;
  • substantially 15.00 parts of ethylene vinyl acetate co-polymer; and
  • substantially 1.20 parts of polyethylene color concentrate.
  • 2. A molding tape for use in providing insulated covering for electrical hardware according to claim 1 wherein said tape is foamed to 40% to 50% of its maximum foaming capability.
  • 3. A molding tape for use in providing insulated covering for electrical hardware according to claim 2 wherein said tape has a thickness of 0.042" plus/minus 0.003".
  • 4. A molding tape for use in providing insulated covering for electrical hardware according to claim 3 wherein said tape has a specific gravity of 0.6-plus/minus 0.05 and hardness Shore A: 82 plus/minus 2.
STATEMENT OF GOVERNMENT INTEREST

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor. This patent application is co-pending with related patent application Ser. No. 003,020 entitled "Method of Making a Cable Assembly for Use in an Antenna Element Assembly" by the same inventors filed on the same date as this patent application. (1) Field of the Invention The present invention relates to an insulated covering for electrical hardware and more particularly to a tape covering for bonding a cable jacket to the strength member of an electrical connector for use in a cable system that is buoyant in seawater. (2) Description of the Prior Art Prior systems used strips of cable jacket material or polyethylene tape or a combination of both. Because the jacket material had been foamed to its optimum buoyant cable characteristics during cable manufacture, further heating/molding always increased the density of the material. This resulted in a less flexible cable section of higher specific gravity that was more prone to stress cracking. These are not desirable characteristics for the present buoyant cable system. The present invention provides a polyethylene tape that is quenched immediately following extrusion so that it is foamed to a predetermined percent of its maximum. The tape is molded to the strength members of an electrical connector and buoyant polyethylene electrical cable jacket to provide a transition from the cable to the connector. The tape has low molding temperature, high flexibility after molding and low density/specific gravity. After molding it closely approximates the basic buoyant polyethylene electrical cable jacket material.

US Referenced Citations (2)
Number Name Date Kind
4499141 Paisley et al. Feb 1985
4525297 Yamane et al. Jun 1985