US1655258A - William edward boyle - Google Patents

Description

Jan. 3, 1928. 1,655,258

w. E. BOYLE HIGH TENSION CABLE AClNT Original Filed March 22, 1923 INVENTOR L a M a; TTOR Y Patented Jan. 3, 1928.

UNITED STATES PATENT OFFICE.

WELIAM EDWARD BOYLE, OF NEW YORK,

N. Y., ASSIGNOB, BY MESNE ASSIGNMENTS,

TO ENGINEERING PRODUCTS CORPORATION, INC., 01: NEW YORK, N. Y., A CORPO- BATION 01: NEW YORK.

HIGH-TENSION-CABLE JOINT.

Continuation of application flerial llq, 626,758, tiled Harch'22, 1823. This annllcation nlcd May 28, 1824.

- Serial No. 715,314.

This invention relates I his application, is a. continuation of my" application Serial N umber 626,756, filed 5 March 22, 1923. The object of the invention generally stated is a high tension cablejoint for underground use which is capable of resisting to an unusual-degree the ordinary break down and disruptive effects of electrical phenomena inhigh voltage transmiss on lines and particularly an improved method of insulation whereby an impaired cable may be economically joined and eifectivelyi' insulated 16 in the open air by an ordinary"'electrical worker to obtain a joint of a break down resistance equal to or greater than that of the original unimpaired cable. 1

1n the progress of the art the voltages ap- 20 plied to underground cables-are constantly being increased and it becomes increasingly diflicult to obtain the-necessary higher dielectrie resistance with reasonable cost and within reasonable dimensions. The dielectric resistance must be'ell'cctive as against puncture or creepage in any direction and involves the necessity of providing a joint as completely free as possible of entrapped air.

By my invention Lam enabled to produce a cheap, relatively small, joint capable of withstanding very high voltages because it has not only a high dielectric resistance againstpuncture, or lateral resistance, but also a very high dielectric resistance in any 5 possible creepage path between contactin insulation parts from the conductor at the joint to the cable sheath or to the metal enclosing the joint. My invention involves a joint in which the bared ends of the conduc- 40 tors to be joined are joined by a metal connector, preferably a sleeve; in which the bared ends of the conductor are covered by a tightly wound insulating tape until'ga co'v ering is thus formed of the same diameter as 5 the usua mill insulation of the cable, this tape preferably covering also previously g enciled ends of the mill insulation; vand in \rhicb'the core formed of the mill insulation -=nd the intervening tightly wound tape is so =.=irro,unded by rol'l f oiled pa or on the like. The resulting 5 join is, o ne wh ch more thoroughly excludes z-lectrioresistance, both laterally and longilengt h is obtained, thecomparatively me- "chanically'nnperfect or soft ends of a rea continuous tightly wound,

air thanany previous joint known to me and for this reason has a greatly increased dietudinally.

I have found, however, that by using a, slightly tapered sheet, it is possible to wind such a roll of sheet insulation, even though roughly cut, around the joint by hand more tightly than is possible if a sheet of uniform width and smooth out is employed; and moreover that by winding the wide end of the sheet first upon the joint a roll-of unusual tightness and-firmiiess throughout its versely wound roll or of a roll formed of a sheet of uniform width being obviated. 'lhe insulating roll may be formed of a single continuous strip would tightly about itself,

but I'have found it preferable .in practice to divide the longer strips into longitudinally separated sections and" wind these sections successively upon each other to form the roll. For example if the total length of strip and depth of roll'exceed certain limits, a roll of greater uniformity in tightness and hardness throughout its depth with greater dielectric strength maythus be obtained.

For a. better understanding of this inventwo, reference may be had to the following detailed description and the-accompanying drawings wherein Y Fig. 1 is a longitudinal section through the cable joint;

Fig. 2 is a plan view of insulating strip employed in this invention;

Fig. 3 is a. view of the" strip rolled up;

Fig. 4 a view illustrating the winding of the strip about the joint;

Fig. 5 is a view of the strip wound about the joint and being tightened and bound thereabout.

Referring to the drawings where like numerals designate similar parts throughout, a cable is illustrated SFig. 1) having an interior conductor 1, a aye-r or' covering of insulation 2 of suitable character and depth, and a metallic sheath 3 of the usual and standard ,chai'actei', this being a cable or 'dinarily employed in underground high tension transmission lines. I ,l P

The cable is illustrated as 'haviii'gfi-li'eeii 'f broken or impaired in 'the vicinity of point 4 and the present invention relates particularly to the repairing of the insulation at this point and the building up of the insulation thereabo'ut of a character and in a manner to render the resistance of the cable to break down at this mintequal to or greater than that of the unimpaired parts of the insulated cable. The conductor parts 1 of the cable are mechanically and electrically connected and joined together by means of a metallic sleeve 5 which surrounds and closely e mbraces the free ends of the conductor 1 and is-seeured and sealed thereto in any suitable suit-able insulating material such as eambric tape," this 'tape beingjwound as indicated until the cable is tilled in completely along the tapered lines 7 and the circumference of the insulation 8 forms an approxh'nate continuation of the circumference of the insula- -tion 2. A tapered strip of oiled insulating paper 9 which is wide enough to bridgeand overla the taperedc'uds of the insulation 2 iS'lllCIl wound and bound tightly about thein'sulation 8 and the insulation'2 as a foundation, the strip being wound wide end first so as to form a built up insulation of cylindrical or roll form 10 about the joint, the gradually narrowing of the tapered strip resulting in a slight sliorteningof the length of the r -ll from the inner surface 11 to the miter surface 12. The drawings which are more or less diagrammatic show the buililin up of this tapered strip along thebevel or mnical edge- 13. After the insulat in; strip is wound --ery tightlyabout the splice to torn: the cylindricalroll 10 it may be secured or ane-bored in posit-iouju 'any suitable manner t obviate any tendency of the roll to loosen. l have illustrated diagrammatically a binding means 14 disposed this operation a suitableinetalhc sheath or container 1;? is positioned over the splice with its ends it; turned over into engagc i ment with the metallicsheath 3, and sealed thereto to-enahlc' asuitalile tiller, such as petroleum -jellyor' other insulator, to be contained within the annular chamber formed thereby 'ilioiit the splice," openings 17 are indicated for introducing this tiller. This filler serves the double purpose of insulating and excluding air from about the s lice.

The strip 9 ma be of any suitablb and length, but have found a paper strip 0.004 inches in thickness, approximately fift (50) '.-feet in length, fourteen (14) inc es wide at the wide-end 18 and gradually narrowing to a width-of twelve (12) inches at the narrower-end 19, suitable for a.cable of 5000. M. copper with 20/32" paper insulation, carryin a tension of 45,000V0lts delta or 26,000 volts to ground.

The strip 9 may be tapered in any suitable 'that the tapering is exaggerated in Fig. 2

to: o'onvemenoem illustration and exposiwidth tion. The strip thus formed is then wound y and bound tightly about'th'e s lice as in'- dicated in Figs. 4 and 5,. with t e wide end 18' wound ad acent to the foundation of insulation 8 and covering .2. I have found it convenient to wind thestrip intq a roll illustrated in' Fig, 3 with the narrow end roll first and the wide end 18 outside as a preliminary step to beginning the winding-of the samejaboutthe splice, Fig, 4 illustrat;- ing the beginning of thewindmg operation, although it is obvious thatthe strip ma be woundlabout the splicefas'indieated ig. 5 without this preliminary rolling step. The drawings illustrate the referred procedure'of bindihg'the joint with the tapered strip 9, when-done by hand, and such nand operation consists essentiall first winding th'e strip more'or less loose y aboutthe joint and then after'such loose'winding without any particular efi'orts' to a tight wrapping, the roll is gripped'b' the hands as ndicat'cdin Fig, 5 -and t e roll bound tightly too by twisting the roll in the direction of wind 7 to tighten the same, .each'suecessive superposed layer of turnt en'ding to bind tightly throughout its. width, against the next lower layer and prevent therebythe formation of air chambers at' any point therebetween through which leakage. might take place with the resultant tendency to disruption and break downQ Thef roll of oiled paper about the circuniference of insulation 10 at either end thereof" for this purpose. 'After;

thus-,enel osing and binding the joint is noticeablysolid and firm throughout its length, even at its ,ends.

Having thusZtlescribed invention what I claim desire to protect by Letters Iat- Tie tape directly surroundin the hated conrounding the cylindrical foundation and ductors, the connector and t e penciled porformed of an elongated sheet of insulation tions of the cable insulation and built up to tightly wound about the foundation and a. diameter approximately that of the cable about itself. 5 insulation to form a substantially continu- In testimony whereof, I have signed my qus cylindrical foundation therewith, and a name to this specification. closely wound roll of insulating material sur- WILLIAM EDWARD BOYLE.

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