RU1785060C - Method for rubber insulated cables jointing - Google Patents

Abstract

The method includes cable cutting, connection of cores, sequential winding in the form of tapes on the spliced portion of the conductive screen of rubber compound based on synthetic rubbers, winding in the form of insulation tapes from rubber compound based on natural and synthetic rubbers, winding in the form of tapes of rubber hose mixture based on natural and synthetic rubbers. Before application, the insulating rubber mixture is cured and coated with a vulcanizing composition based on natural rubber, the casing is pre-vulcanized and, when the tape is wound, coated with a layer based composition of chloroprene rubber. Vulcanization is carried out at room temperature. 3 tab. SB with

Description

The invention relates to a method for splicing power cables with rubber insulation and can be used in the electrical industry for the repair and installation of cable lines.

The invention makes it possible to significantly simplify the existing technology for repairing and splicing cables with rubber insulation, reducing labor costs, energy consumption, splicing and repairing cables at low temperatures, and increasing the bond strength between the layers.

Various methods of cable splicing are known, which consist in winding rubber bands onto a connection section with a preliminary glueing thereof.

site with subsequent vulcanization under pressure at high temperature.

These methods cannot provide repair and connection of cables with various compositions of rubbers included in the cable elements.

Closest to the proposed technical essence is a method of splicing cables with rubber insulation, which consists in cutting the end nodes of the cables, connecting the cores, applying repair material to the spliced section: insulating rubber mixture, wt. per 100 parts by weight rubber: NK-70, SKD-30, sulfur - 0.17, tiuram - 2.55, zinc oxide - 5.00, neozone-D (naphtham-2) - 1.0. dvj 00

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athen-FP -3.0. AF-1 alloy - 15.0, stearic acid - 1.0, bitumen varnish - 3.0, separated chalk -41.3, talc - 40, carbon black - 10; electrically conductive rubber composition, m.h. per 100 parts by weight rubber: NK-100: thiuram - 3.2, captax -1.1. zinc oxide - 5.0, neozone-D (naphtham-2) - 1.0, stearic acid - 3.2, softener PP-32, carbon black - 113.0; hose rubber composition, parts by weight per part by weight, rubber: NK-60. SKD-40, sulfur - 2.5, captax - 0.70, zinc oxide - 5.0, neoson-D (naphtham-2) - 1.0, stearic acid 5.0, paraffin - 10.0, carbon black - 72.9, rosin - 3.0 and glue between different layers of such rubbers, followed by vulcanization in a mold at a temperature of 140-150 ° С and further exposure of the repaired area in a tank with cold water

However, the known method, which has until now been widely used in the splicing and repair of cables with rubber insulation, has a number of significant disadvantages, namely: vulcanization of the spliced portion of the cable can be carried out only at high temperatures (140-150 ° C) mold under pressure. The known method requires high energy consumption and is very laborious; due to the low strength between the layers, unsatisfactory moisture resistance of the spliced area and insufficient adhesion after wetting between cable elements are observed.

An object of the invention is to simplify splicing technology while increasing the cable insulation resistance.

This goal is achieved by the fact that in the method of splicing power cables with rubber insulation, including their butchering, connecting the cores, sequentially winding onto the spliced portion of the electrically conductive screen in the form of tapes of a rubber mixture comprising synthetic rubber, tetramethylthiurism disulfide, 2-mer captobenzthiazole, zinc oxide, phenyl naphthylamine. stearic acid, emollient, carbon black, insulation from a rubber compound including natural rubber, sulfur, synthetic rubber, tetramethylthiuram disulfide, zinc oxide, phenyl / naphthylamine, stearic acid, talc, separated chalk and a hose shell made of a rubber mixture comprising natural rubber, synthetic unsaturated rubber, sulfur, 2-mercaptobenzthiazole, zinc oxide, phenyl / naphthylamine, stearic acid, rosin, carbon black and subsequent vulcanization, characterized in that in order to simplify Splicing technologies while increasing the cable insulation resistance in a rubber mixture for a screen use a mixture of stereo-regulating butadiene and isoprene rubbers, taken in a weight ratio of (45-55): (55-45) as synthetic rubber. in the following ratio of components, parts by weight: stereoregular butadiene rubber - 45-55, isoprene rubber 45-55. tetramethylthiuramdisulfide 3.8-4.2; 2-mercaptobenzthiazole - 0.8-1.2; zinc oxide - 5.0-7.0; phenyl- / naphthylamine - 1.5-1.8; stearic acid 6.0-7.0, an alloy of paraffin and petrolatum - 25-28; technical carbon - 115-143. in the rubber mixture for isolation, styrene-butadiene rubber is used as synthetic rubber in the following ratio of composition components (parts by weight): natural rubber-70-80, styrene-butadiene rubber - 20-30; sulfur - 0.18-3.0; tetramethylthiuram disulfide - 2.0-3.0 :, zinc oxide - 2.8-3.5; phenyl- / 3-naphthalamine - 1.2-1.6; stearic acid - 1.8-2.5; separated chalk - 80-110; talc - 40-60, into the rubber composition for the hose sheath, tetramethylthiuram disulfide, bitumen varnish and p: isopropyl-p-phenylenediamine are added in the following ratio (parts by weight): natural rubber - 65-75; stereoregular butadiene rubber 25-35; sulfur - 2.0-3.0; tetramethylthiuram disulfide - 0.5-2.5; 2-mercaptobenzothiazole - 0.5-1.0: zinc oxide - 4.0-6.0; phenyl- / naphthylamine 0.8-1.2; p-isopropyl-p-phenylenediamine - 1.8-2.2; stearic acid - 4.5-5.5; bitumen varnish - 4.5-5.0; technical carbon furnace - 60-75; rosin - 25-32; moreover, before application, the insulating rubber mixture is pre-vulcanized to a tensile strength (MPa): 5.4-5.8, and when winding the tape, it is smeared layer by layer with a composition composition, parts by weight: natural rubber 95-100; zinc dimethyl dithiocarbomate - 9-11; polyethylene glycol - 0.9-1.1; tetramethylthiuram disulfide - 4.0-6.0; chloroform - 240-260, and the rubber mixture along the length of the hose sheath is pre-vulcanized to a strength level (MPa) of 14.8-15.5 and when winding the tape is coated with layers of the composition composition (parts by weight): chloroprene rubber-95-100 ; chlorinated polypropylene - 9.0-11. zinc oxide - 18.0-22.0; Kumaron-indenova resin - 8.0-12.0,

aromatic hydrocarbon softener 4.0-6.0; polyethylene glycol - 0.8-1.2; octaphor - 2.8-3.2; zinc stearate - 0.9-1.1; sulfur - 0.9-1.1; tetramethylthiuradi sulfide 0.9-1.1; furnace carbon black-0, 9-1.1; gasoline - 100-200; ethyl acetate - 200-220; leukonate - 33.0-37.0; after which vulcanization is carried out at normal temperature.

The repaired cable is tested in accordance with the applicable technical documentation.

The proposed method of splicing cables with rubber insulation includes the following operations: cutting the cores and connecting them, degreasing the outer surfaces of the connected cables by wiping them with gasoline or an alcohol-gasoline mixture, followed by air drying, preparing vulcanized repair materials in the form of a tape, preparing the ends of the subject cable repair, fixing the ends of the core in the sleeve, wiping the prepared repair material (tapes) with gasoline and drying them, applying an electrically conductive screen to the core While washing each layer with vulcanizing liquid, applying an insulating layer with one layer of electrical insulating rubber overlapping each layer with vulcanizing liquid, restoring the clear screen and winding the rubberized fabric tape, smearing the wound fabric tape with glue, followed by drying 3-5 min, applying pre-coated with a glue hose sheath, drying the entire cable structure at room temperature for 50-60 minutes.

All materials used are produced by domestic industry in accordance with the existing technical documentation.

This method has been tested for splicing cable products with rubber insulation of the KGE brand at 6 kV.

The invention is illustrated by the following example.

Example. The ends of the cable of the KGE Z1 0 1 10 mm2 brand, prepared for splicing, are cut with a hacksaw. In a section 600 mm long from the end of the cable, the surface of the bolt is cleaned of dirt and wiped with a clean rag soaked in gasoline. At a distance of 350 mm, annular and longitudinal cuts are made on the sheath and the waist shield and the sheath and back shield are removed from the end of the cable. At a distance of 5 mm from the notch, the sheath and the waist screen are cut into a cone. Cone surface and

the adjacent sections of the casing and the waist screen are cleaned with a drastic file until a rough surface is formed, then they are wiped with a clean cloth soaked in gasoline and dried for 3-5 minutes. The insulated cores are untwisted and straightened. At a distance of 125 mm from the end, at each core, rubber insulation is cut with a knife with

0 conductive screen around the circumference and along the vein and remove it. Similarly, another cable is prepared for connection.

Lay the cut ends of the connecting cables against each other and. combining the ends of the main conductors, they put a sleeve on one end of the prepared core, bring it into contact with the insulation, then insert it into

0 sleeve the second end of the connecting core, shift the sleeve so that both ends of the core enter the sleeve to the same depth. The sleeve is fixed at the ends by crimping with PK-2 pliers. In a similar way, all other veins are connected.

Before restoration, the end face of the insulation is cut into a cone at half the length of the sleeve.

0 Repair insulating rubber and electrically conductive rubber 6 Forms Tapes with a width of 15-20 mm and a thickness of 2.0-2.5 mm are wiped on both sides with a clean, damp cloth moistened with gasoline and allowed to dry.

5 4-5 minutes. A section of a core with a cut-off conductive screen and a junction of conductors is tightly wrapped with 50% overlap of turns with one layer of tape from an electrically conductive rubber compound. Then, an insulating rubber mixture is imposed on this section, preliminarily vulcanized to a degree of swelling in m-xylene up to 1000-1200% (corresponds to a tensile strength of 5.4-5.8 MPa) in layers with 50% overlap. At the end of the winding of each layer, the surface is lubricated with a vulcanizing fluid. Winding is carried out until the outer diameter of the restored insulation is 5

0 mm exceed the diameter of the core along the external conductive screen. The insulation applied to the core is tightly wrapped with 50% overlap of the wires with one layer of electrically conductive rubber and coated

5 vulcanizing liquid. To restore laziness of the waist shield and sheath, the indentation between the cores is filled with flat inserts cut from a 3-4-fold folded electrically conductive rubber. The liners are secured with a tape of electrically conductive rubber, wrapped with a 5% overlap until then. until the diameter of the wrapped section is 5 mm larger than the outer waist screen. A layer of rubberized fabric tape with a 50% overlap is wound around the surface to restore the waist screen. The wound fabric tape is liberally greased with glue with a hardener (leukonate), taken at a ratio of 1:20. The conically incised shell is carefully roughened, evenly lubricated with glue and allowed to dry for 4-5 minutes.

Pre-vulcanized hose rubber mixture pre-vulcanized to a degree of swelling in m-xylene up to 90-100% (corresponding to strength 15.8–15.5 MPa) is cut into tapes, wiped with a rag moistened with gasoline, allowed to dry for 3-4 minutes and then coated with glue on both sides and allowed to dry. The hose sheath is restored over the section wrapped with fabric tape, by wrapping it with tape from repair hose rubber with 50% overlap in layers until the diameter of the section being restored is 5 mm larger than the outer diameter of the cable for a length of 20 mm. On top of each layer, a vulcanizing fluid is dried and dried for 3-5 minutes.

After restoration of the shell, the joint is greased 2 times with glue and allowed to air dry for 50-60 minutes.

After performing all the above operations, the reconstructed section is tested with increased voltage and the insulation resistance is determined for compliance with the requirements of TU 16.K73.02-88.

 In the table. Compositions of mixtures are shown in Tables 1 and 2, and in Table-3 the insulation resistance of the repaired cable section with (rubber insulation).

Said method can be used to repair elements of cable products with rubber insulation.

As follows from the table. 2 of the test results of the KGE brand cable 3 x 50 + 1x10 mm2, the proposed method using the compositions developed for this allows 1.8-2.0 times higher insulation resistance of the cable compared to the known method and significantly simplifies the splice technology.

Claims (1)

The claims A method of splicing power cables with rubber insulation, including cutting them, connecting conductors. sequentially winding onto the spliced portion of the electrically conductive screen in the form of tapes made of rubber compound, including synthetic rubber, tetramethylthiuram disulfide, 2-mercaptobenzthiazole, zinc oxide, phenyl / 3-naphthylamine, stearic acid, softener, carbon black, rubber compound insulation including natural rubber, sulfur, synthetic rubber, tetramethylthiuram disulfide, zinc oxide, phenyl / naphthylamine, stearic acid, talc, separated chalk, and a hose shell made from a rubber mixture including natural rubber, synthetic unsaturated rubber, sulfur, 2-mercaptobenzothiazole. zinc oxide, phenylnaphthylamine, stearic acid, rosin, carbon black, and subsequent vulcanization, characterized in that, in order to simplify the splicing technology while increasing the cable insulation resistance, a mixture of stereo-regulating butadiene and isoprene rubbers is used as synthetic rubber in the rubber composition for the screen; taken in the mass ratio (45-55): (55-45), in the following ratio of components, wt.h .: stereo-butadiene rubber-45-55; isoprene rubber 45-55; tetramethylthiuram disulfide 3.84, 2; 2-mercaptobenzthiazole - 0.8-1.2; zinc oxide 5.0-7.0; phenyl- / 3-naphthylamine - 1.5-1.8; stearic acid 6.0-7.0; an alloy of paraffin and petrolatum - 25-28; carbon black - 115-143. in rubber compound for isolations, styrene-butadiene rubber is used as synthetic rubber, in the following ratio of components of the composition, parts by weight: natural rubber - 70-80; styrene butadiene rubber - 20-30; sulfur - 0.18-3.0; tetramethylthiuram disulfide - 2.0-3.0; zinc oxide - 2.8-3.5; phenyl-dnaphthylamine - 1.2-1.6; stearic acid - 1.8-2.5; separated chalk - 80-110; talc - 40-60, tetramethylthiuram disulfide, bitumen varnish and p-isopropyl-p-phenylenediamine are further reduced to a rubber composition for a hose shell in the following ratio of components, parts by weight: natural rubber 65-75; stereo adjustable butadiene rubber - 25-35; sulfur - 2.0-3.0; tetramethylthiuram disulfide 0.5-2.5; 2-mercaptobenzothiazole - 0.5-1.0; zinc oxide - 4.0-6.0; phenyl- / 3-naphthylamine-0.8-1.2: ni- -isopropyl-p-phenylenediamine -1.8-2.2; stearic acid - 4.5-5.5; bitumen varnish - 4.5-5.5; technical furnace carbon - 60-75; rosin - 25-32. moreover, before applying the insulating rubber mixture is pre-vulcanized to the degree tensile strength, MPa 5.4-5.8 and when winding the tape it is smeared layer by layer with the composition, max.,: natural rubber - 95-100; zinc dimethyldithiocarbomatum - 9-11: polyethylene glyco-0.9-1.1; tetramethylthiuram disulfide - 4.0-6.0; chloroform - 240-260, and the rubber mixture for the hose sheath is pre-vulcanized to a strength of MPa 14.8-15.5 and when winding the tape is coated with layers of the composition, wt.h .: chloroprene rubber - 95-100; chlorinated polypropylene - 9.0-11.00; zinc oxide -18.0-22.0; coumaron-indene resin - 8.0-12.0, aromatic hydrocarbon softener - 4.0-6.0; polyethylene glycol - 0.81 .2; octaphor - 2.8-3.2; zinc stearate - 0.9-1.1; sulfur - 0.9-1.1; tetramethylthiuram disulfide - 0.9-1.1; technical furnace carbon - 0.9-1.1; gasoline - 100-120; ethyl acetate - 200-220; leukonate - 33.0-37.0. after which vulcanization is carried out at normal temperature. Table 2 The composition of the adhesive composition Table3