JPS608A - Oil-immersed insulating cable - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to oil-immersed insulated cables. BACKGROUND ART Biaxially stretched polypropylene films with paper laminated on both sides, and non-stretched polypropylene films with paper laminated on both sides are conventionally known.

However, oil-immersed insulated cables using these cables have the disadvantage that the insulating oil swells to a large extent, causing the insulating layer to bunch up, resulting in poor oil flow.

For this reason, as a result of intensive research, the density was 0.905 to 0.
9157/crn3, an oil-immersed insulated cable using a laminated paper made by laminating biaxially oriented polypropylene or polyethylene terephthalate film on one or both sides of a polypropylene film with birefringence in the range of 0.020 to 0.035 is as described above. I discovered that it is possible to overcome these shortcomings.

The density of the polypropylene film used here is 0.90
5-0.91517 cm8, preferably 0.0912
t/lyn". If the density is lower than this range, swelling due to oil will increase; if the density is higher than this range, the film will become brittle and its mechanical strength will decrease. Also, the birefringence of the polypropylene film is 0.020 to 0.035, preferably 0.025 to 0.0.
It needs to be in the range of 32. If the birefringence is smaller than this range, swelling due to oil will increase, and if it is thicker than this range, the film will be more likely to break.

The birefringence of the biaxially oriented polypropylene film laminated with this polypropylene is in the range of 0 to 0.018, and the birefringence of the biaxially oriented polyethylene tereclate film is in the range of 0 to 0.050. be.

Examples will be explained below. First, an unstretched polypropylene film is prepared by a conventional method. This unstretched film
It is inserted between a set of rolling rolls and rolled. The rolling magnification is 7
About 10 times is preferable. The pressure during rolling is 100-10
00 kg/an is preferred.

The invention product thus produced (90μ), a biaxially oriented polypropylene film, and a biaxially oriented polyethylene terephthalate film (30μ) were laminated using an adhesive consisting of terephthalic acid and neopentyl glycol.

This laminated paper was cut into tapes with a width of 1Qmm, and 10 pieces of this tape were wrapped around 150111 m2 of copper stranded wire using a 1/3 lamp. On top of this, place 3 pieces of 0.2m thick copper tape.
I wrapped 1/3 of a sheet with a lamp.

The cable thus completed (2.5m) is 100'G
of alkylbenzene (viscosity l〇7 inches stokes 30°
It was immersed in C for 4.8 hours. After soaking, radius 5ocrn
The test was conducted 16 times by wrapping it around a cylinder. After the final test, the AC breakdown value was determined. The results are shown in the table below along with comparative examples.

As shown in the table above, the Examples exhibit superior properties compared to the Comparative Examples. In this way, the invention was completed.

Procedural amendment document January 1980/P date 1, Indication of case Patent application No. 107294 No. 107294 of 1988 Name of invention Oil immersion insulated cable 3, Person making the amendment Relationship to the case Patent applicant address Higashi-ku, Osaka City 5-15 Kitahama Name (213) President of Sumitomo Electric Industries Co., Ltd. Tetsubu Yogami Agent address 1-1-3 Shimaya, Konohana-ku, Osaka-shi Sumitomo Electric Industries Co., Ltd. 6, Specification subject to amendment 7, Amendment Please submit a clearly written detailed statement with the contents typed as a separate sheet.

Claims (1)

[Claims] Density 0.90.5-0.915g/C1n8, birefringence 0
．． 020~0,. An oil-immersed insulated cable using a laminated paper made by laminating a biaxially oriented polypropylene film or a biaxially oriented polyethylene terrestrial film on one or both sides of a polypropylene film falling within the range of 035.