Claims
- 1. In a method for manufacturing an oil-filled electric cable comprising a conductor, a semi-conductive screen around and in contact with said conductor, a solid, stratified insulation around said screen, a metal sheath around said insulation and an insulating oil impregnating said insulation, a method for forming said insulation which comprises the steps of:
- providing a separate film tape of plastic material;
- impregnating said film tape with an insulating oil to cause it to at least partially swell;
- removing the last-mentioned said insulating oil from the surfaces of said film tape;
- providing a tape of cellulosic paper having a moisture content such that the reduction in thickness thereof upon drying is substantially equal to the swelling in thickness of said film tape when the cable is filled with the insulating oil;
- after the insulating oil has been removed from the surfaces of the film tape, winding said tape of cellulosic paper and said film tape independently of each other in alternate and adjacent layers around said semi-conductive screen; and
- after said alternate layers have been formed, drying said tape of cellulosic paper and impregnating said tape of cellulosic material and contacting said film tape with the first-mentioned said insulating oil.
- 2. A method as set forth in claim 1 wherein said tape of cellulosic material has, a moisture content not greater than 2%.
- 3. Method as set forth in claim 1 wherein said plastic material is a plastic material which swells when immersed in said insulating oil.
- 4. Method as set forth in claim 1 wherein the insulating oil is removed from the surfaces of the film tape by washing the film tape in a detergent and removing the detergent from the surfaces of the film tape with a stream of air.
Priority Claims (1)
Number |
Date |
Country |
Kind |
19182 A/84 |
Jan 1984 |
ITX |
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Parent Case Info
This is a division, of application Ser. No. 690,666 filed Jan. 11, 1985 now U.S. Pat. No. 4,602,101.
US Referenced Citations (8)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0129755 |
Jan 1985 |
EPX |
1045527 |
Oct 1966 |
GBX |
Divisions (1)
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Number |
Date |
Country |
Parent |
690666 |
Jan 1985 |
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