JPH0715822A - Step stripping method at joint of high voltage power cable - Google Patents

Abstract

PURPOSE:To shorten the work time in the step stripping process at the joint of high voltage power cable while enhancing the quality and safety. CONSTITUTION:A high voltage power cable 1 is fixed with a stopper 11 and the upper part thereof is rotated while being clamped by a slicing tool thus slicing a vinyl sheath 2. A replacing die held in a die winder is fitted to the tip of the sheath which is stripped up to a sliced part 21a by means of a strip cutter. A strip band is then fixed to an exposed copper shield 4 which is then cut, at the upper part thereof, by means of a longitudinal cutter and stripped. Outer semiconductor layer 5 is then sliced 21b by a slicing tool on the stopper 11 fixed to the sheath and the upper part thereof is stripped. Subsequently, the replacing die is fitted to an insulator 6 and rotated thus cutting the insulator spirally and stripping. A beveling tool is then rotated to bevel 10 the end of the insulator in conjunction with the stopper 11 thus stripping the sheath, conductor, insulator, outer semiconductor layer, copper shield, and sheath stepwise with predetermined dimensions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a triplex type crosslinked polyethylene insulated vinyl sheath power cable connection in which a conductor is insulated with crosslinked polyethylene and a protective coating is provided with a compound mainly composed of vinyl chloride resin (hereinafter referred to as vinyl). The present invention relates to an improvement in the method of stripping the terminal connection portion for construction.

[0002]

2. Description of the Related Art This triplex type crosslinked polyethylene insulated vinyl sheath power cable (hereinafter referred to as "high voltage power cable") is formed by uniformly extruding and coating an inner semiconductive layer on the conductor of a compressed strand of annealed copper wire and then crosslinking it. An insulator that concentrically coats polyethylene or a mixture thereof, an outer semiconductive layer on which a semiconductive layer is uniformly extruded and coated, and a 1/6 annealed copper tape is lapped 1/6 It is composed of a shielding copper, and a vinyl sheath (hereinafter referred to as a sheath) in which vinyl is concentrically coated on the annealed copper tape (there is also a nonwoven fabric on which the annealed copper tape is superposed and wound).

Such a high-voltage power cable is divided into a straight connection portion of the underground power distribution section and a terminal connection to a ground connection box such as a building, an electric pole, and a substation. In recent years, the number of connection boxes has increased along with the extension of the cable. is doing.

In these connection work steps, common to the terminal connection and the straight line connection, the cable is straightened, the cable is temporarily supported, the core of the wire is cut, and the cable step is stripped. Compression, taping,
For cable support, and for straight connection, insert spacer,
The work steps of compression, insulation tube insertion, ground wire attachment, taping, and cable support are required in that order.In these operations, the multi-layered high-voltage power cable is cut from its cable tip with an electric knife. The conductor, the insulator, the outer semi-conductive layer, and the shielding copper were stripped to a specified length so as to expose the copper in a precise dimension, which required considerable skill.

[0005]

In the step of stripping the high-voltage power cable, which is the most troublesome of these connection work steps, the outer sheath of the high-voltage power cable is first removed from the tip by using an electric knife according to the dimensional ruler. Make a round cut at the length of the specified dimension, then open the sheath with your left hand and make a vertical cut from the upper end, but during the vertical cut of the sheath, the knife blade slips and you are likely to cut your hand and hat it. In many cases, the sheath stripping with an electric knife, stripping of the outer semiconductive layer, and stripping of the insulator occupy about 80% of the step stripping process. There is also a risk of damage to the equipment, and almost 70% of the high-voltage power cable connection process work is spent on the cable step stripping process, which not only requires skill but also a long working time. Was Tsu.

The present invention solves these problems and provides a step stripping method for improving construction quality, shortening working time, and ensuring work safety.

[0007]

In order to achieve the above object, the present invention provides a two-part split in which a stopper is attached at a specified length position from the tip of a high-voltage power cable according to a size ruler, and a blade is attached locally over the inner diameter. Insert the cable with a freely openable and closable circular cutting tool that has a cylindrical part and a handle part and rotate it on the stopper to cut the sheath into rings.Then, turn the die and replace it in the tube part. Continuously spirally cut the sheath with a peeling blade attached to the die and peel off to the sliced portion, then also peel off the cotton tape around the shield copper presser, and then strip off the shield copper exposed above the sheath. Attach, and cut the shielded copper on it with the vertical cutting tool.

Next, the stopper is replaced with the stripped upper part of the sheath, and a circular cutting tool of the same outer semiconductive layer having an inner diameter smaller than that of the circular cutting tool is rotated on the stopper to cut the outer semiconductive layer into a circle. Then, the outer semiconductive layer is vertically cut with a vertical cutting tool and peeled off, the stopper is stopped at a predetermined length position from the exposed tip of the insulator, and a small diameter hole is formed in the die turning cylinder. Replacing the exchange die it has and fitting it on the tip of the insulator and rotating it, the insulator is attached to the insulator to spirally cut the insulator up to the upper surface of the stopper and strip it to expose the conductor. Fit a chamfering tool on the die turning and rotate it on the stopper to chamfer the upper edge of the insulator, and then conductor with a length according to the dimension ruler,
The insulator, the outer semiconductive layer, and the shielding copper could be exposed.

[0009]

In the step stripping method for the high voltage power cable of the present invention,
First, determine the length position where the sheath is stripped from the cut end of the high-voltage power cable using a dimensional ruler, and use that position as a reference line to attach a stopper that clamps and fixes the cable to the main unit with the base and the movable base that moves back and forth with screws. . On the stopper's upper surface, the cable is sandwiched by a circular cutting tool that has a cylinder part that can be opened and closed with a hinge as a fulcrum and a handle part, and the cable is rotated, so that the peeling blade attached to the inner part of the cylinder part Cut and cut the sheath into a circle.

Next, by replacing the exchange die with the die rotating cylinder part, inserting it into the end of the cable and rotating it, the sheath is continuously spiraled by a peeling blade provided on one side surface of the V-shaped inclined surface of the exchange die. It is discharged while being cut, and peeled off to the position of the wheel slice. Next, strip the exposed spirally wound cotton tape to the sliced area, attach a stripping band of a specified width on the shielding copper at the top of the sheath, and use a rotary blade of a vertical cutting tool (vertical cutter) to reach the band. Cut vertically and peel off.

Next, the stopper is replaced at the upper end of the sheath, and a circular cutting tool for the outer semiconductive layer similar to the circular cutting tool is rotated on the stopper to cut the outer semiconductive layer into a circular slice and then peeled off. The insulator is exposed, and this stopper is attached on the insulator at the specified length from the cable tip, and it is inserted into the die rotating cylindrical part with an exchange die with a small hole inner diameter and then inserted into the insulator tip to rotate. By doing so, the insulator is spirally cut by the peeling blade attached to the V-shaped recess, and is horizontally cut by the rotation along the upper surface of the stopper to be peeled off to expose the conductor to a predetermined length. To be done.

Finally, the stopper is replaced from the tip of the cable to a predetermined length position of the insulator, the chamfering tool is fitted to the cylindrical portion of the die and screwed, and the blade of the chamfering tool is rotated by rotating on the stopper. Then, the outer peripheral portion of the upper end of the insulator is obliquely cut and chamfered, so that the conductor, the insulator, the outer semiconductive layer, and the shielding copper can be exposed in a step according to the dimension according to the dimension ruler.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of the present invention, a tool for use in a step stripping work in a high voltage power cable connecting work shown in the drawings and its use will be described below. FIG. 1 shows a dimensional ruler used for stripping the high-voltage power cable and a state in which the multi-layered high-voltage power cable 1 is peeled off according to the specified dimensions.
2 is an outer sheath, 3 is a cotton tape, 4 is a shielding copper wrapped with a copper tape, 5 is an outer semiconductive layer, 6 is an insulator, and 7 is a conductor. In order to expose the length b of the shielding copper 4 according to the specified dimensions, the length c of the outer semiconductive layer 5, the length d of the insulator 6, and the length d of the conductor 7 in the high-voltage power cable connection work. A linear ruler for cable straight connection used in the step stripping work step, and 8a is a dimension ruler for cable termination junction box.

Reference character a indicates a defined length of stripping from the tip of the conductor 7 of the high-voltage power cable 1 to the tip of the sheath 2, and the shaded portions X, Y, and Z are based on the specified length a. The step of the high-voltage power cable 1 indicates the mounting and fixing position and the order in which the stopper 11 shown in FIG. The shaded portion Y indicates the stopper mounting / fixing position when the outer semiconductive layer is peeled, and the shaded portion Z indicates the stopper mounting / fixing position when the insulator is peeled.

As an example, a CV for 325 to 400 sq.
In case of T cable straight connection, a is 335 mm, b is 20 m
m and c are 10 mm, e is 17 mm, d is 198 mm, and 1
For 50 to 250 sq, a is 318 mm, b is 20 mm, c
Is 10 mm, e is 90 mm, and d is 198 mm. On the other hand, 2
For CVT cable termination connection for 50-325sq,
a is 385 mm, b is 20 mm, c is 10 mm, e is 120 m
m and d are 235 mm, for 100 to 200 sq, a is 37
5 mm, b is 20 mm, c is 10 mm, e is 115 mm, d is 2
The prescribed dimension of stripping, such as 30 mm, is determined, and stripping of the power cable according to the dimension is required.

FIG. 2 shows a stopper 11, which is a V-shaped fixed claw 13 provided on one side of a U-shaped main body 12.
And a V-shaped movable claw 14 which is opposed to the claw 14 and which is advanced and retracted by a thumbscrew 15, and is detachably attached across a predetermined position of the cable 1.

FIG. 3 shows a circular cutting tool, which is provided with a halved cylindrical portion 16 and a handle portion 17 which are opened and closed with a hinge 9 at one end as a fulcrum, and an end face portion of the cylindrical portion 16 traverses a side portion of the inner hole. Thus, the blade body 18 is attached by the set screw 19, and the inner surface is provided with a circular cutting tool 21 having a circular guide 20 that turns around the cable.

Also, such a circular cutting tool having different hole inner diameters and distances from the center of rotation to the blade 18 is prepared so that the sheath 2 and the outer semiconductive layer 5 can be easily peeled from a predetermined position. It is used to accurately pre-cut only those thicknesses, and when these are sliced and cut, they are sequentially moved to the positions shown by the shaded portions X and Y in the figure in accordance with the work steps of the high-voltage power cable in FIG. The stopper 11 is attached and replaced, and the circular cutting tool 21 is rotated by using the upper surface of the stopper as a guide to horizontally slice the sheath and the outer semiconductive layer 5 with these blade bodies 18, thereby cutting the sheath 2 It is possible to form a wheel-cutting portion 21a for peeling off and a wheel-cutting portion 21b for peeling off the outer semiconductive layer 5.

FIG. 4 shows a state of use in which an exchange die 29 for cutting a sheath is set in the tubular portion 22 of the die turning 23. Inside the cylindrical portion 22 of the die turning 23, there is a collar cylinder 25 having a guide hole 24 in the center, and an opening 26 cut out in a semicircular shape slightly larger than the inner diameter of the sheath in the upper portion thereof, and the semicircular circumference of the side wall portion thereof. An exchange die 29 for cutting a sheath is provided on the inclined surface of the V-shaped inclined surface 27, which is obliquely peeled off and attached to the inner diameter side portion of the guide hole 24, and is attached to the cylindrical portion 22 of the die rotating member 23. It is fitted in the inside through a collar cylinder 25 and fixed by a fixing screw 30 to be mounted.

FIG. 5 shows an exchange die for stripping an insulator, which has the same structure as the die, and has a guide hole 24 at the bottom.
A flanged cylinder 25a having a and an opening 26a slightly larger than the outer diameter of the conductor 7 in the upper part thereof, and a stripping blade 28a obliquely formed on the slope of the V-shaped sloped surface 27a of the semicircle of the side wall. Is a replacement die 29a for stripping the insulator, which is attached by appropriately projecting it to the inner diameter side portion of the guide hole 24a.

These exchange dies 29 and 29a are selected in accordance with the work order and are mounted in the cylindrical body 22 of the die rotating 23, fitted into the sheath 2 of the cable and the end portion of the insulator 6, and then the die rotating 23 Is rotated to be spirally cut from the tip of the sheath 2 or the insulator 6 by the peeling blades 28 or 28a provided on the exchange dies 29 or 29a.
After reaching a, and in the case of the insulator 6, by rotating the upper surface of the stopper several times, the sheath 2 and the insulator 6 are accurately and easily cut and peeled to a prescribed dimensional length, and the external semiconductive layer 5 is removed. It is possible to perform step stripping work for exposing the conductor 7 and the conductor 7.

FIG. 6 shows an annular structure made of a thin stainless steel strip having a predetermined width w for mounting on the shielding copper tape 4, and the worm of the worm handle 35 meshes with the outer periphery of the overlapping portion. Adjustment band 3 for adjusting the inner diameter
Figure 6 shows a tightening band 34 having 6

FIG. 7 shows a vertical cutting tool 39 in which a rotary blade 38 is attached to the tip of a handle 37 for vertically cutting and peeling the shielding copper tape 4. Figure 8 shows dice turning 2
3 shows a chamfering tool 33 to be set in the cylindrical portion 22 of No. 3, in which one side of a cylindrical body 33a having a guide hole 31 corresponding to the outer diameter of the insulator 6 is obliquely cut to form a sloped recess. 32
A chamfering blade 32 is attached to a so that the corner of the top of the guide hole 31 is cut obliquely. The chamfering tool 33 is mounted in the cylindrical portion 22 of the die turning device 23, and is rotated on the stopper 11 attached to the stopper attachment fixing position Z shown by the hatched portion in the upper part of FIG. The corner is chamfered 10.

Through the above work steps, in the cable connection work, as shown in FIG. 1, the conductor 7, the insulator 6, the outer semiconductive layer are defined with reference to the length a from the tip of the high-voltage power cable 1 to the specified dimension. 5, each of the shielding copper tapes 4 can be exposed and formed.

[0025]

INDUSTRIAL APPLICABILITY The present invention is applied to the construction work of a triplex type crosslinked polyethylene insulation sheath power cable in which a conductor is insulated with crosslinked polyethylene and a protective coating is applied with a compound mainly containing vinyl chloride resin, as described above. Since the conductor, insulator, outer semiconductive layer, and shielding copper tape are exposed stepwise from the outer sheath to a predetermined length by the construction method, all cable step stripping work steps are performed using tools, There is no danger of damaging your hands or other parts as compared with the stripping work with a tool knife, and the incidence of cases such as hating or nearing during the work is 0.32 (19 / 82 times)
On the other hand, since it is almost nonexistent, it can greatly contribute to work stability and safety.

Moreover, the work of stripping the cable step of the specified length can be performed accurately in accordance with the size ruler, and the working time has conventionally required 541 seconds per cable on average for a skilled person. According to the construction method, even an unskilled person averages 250
The work time was greatly reduced to less than half, including the step stripping work process being completed in about two seconds. In addition, regardless of skill level, anyone can easily and safely obtain high construction quality, which is an economical method.

[Brief description of drawings]

FIG. 1 shows the stripped state of a triplex type cross-linked polyethylene insulated vinyl sheath high voltage power cable and its size ruler, (A) for straight connection of a 6600V high voltage power cable, and (B) a cable termination. It is for a connection box.

2A and 2B show a stopper used for stripping a step of a high-voltage power cable connection portion in the present invention, in which FIG. 2C is a front view thereof, and FIG.

FIG. 3 shows a sheath circular cutting tool, (E) is a front view,
(F) is a side view in which a part thereof is cut.

4A and 4B show a die rotating tool and a replacement die for cutting and peeling the sheath, which is set inside the die rotating tool. FIG. 4G is a plan view, FIG. 4H is a front view, and FIG. 4I is a sectional view of the replacement die.

FIG. 5 shows an exchange die for peeling an insulator, (J) is a plan view, and (K) is a front view.

FIG. 6 shows a stripping band to be mounted on a shielding copper tape, (L) is a plan view and (M) is a front view.

FIG. 7 shows a vertical cutting tool for a shielding copper tape, (N) is a side view, and (P) is a front view.

FIG. 8 shows an upper end chamfering tool for an insulator, (Q) is a plan view, (R) is a front view, and (S) is a sectional view.

[Explanation of symbols]

 1 High-voltage power cable 2 Vinyl sheath 3 Cotton tape 4 Shielding copper tape 5 Outer semi-conductive layer 6 Insulator 7 Conductor 8, 8a Dimension ruler 9 Hinge 10 Chamfer 11 Stopper 12 Stopper body 13 Fixed claw 14 Movable claw 15 Thumb screw 16 20% Cylindrical part 17 Handle part 18 Blade 19 Set screw 20 Circular guide 21 Circular cutting tool 21a, 21b Wheel cutting part 22 Cylindrical part 23 Die turning 24, 24a Guide hole 25, 25a Collar cylinder 26, 26a Open hole 27, 27a V-shaped inclination Surface 28, 28a Peeling blade 29, 29a Exchange die 30 Stop screw 31 Guide hole 32 Slope blade 32a Slope recess 33 Chamfering tool 33a Cylinder 34 Clamping band 35 Worm handle 36 Adjustment band 37 Grip 38 Rotating blade 39 Vertical cutting tool

Front page continuation (72) Inventor Toysei Fukuda 4-8-20 Takeshima, Nishiyodogawa-ku, Osaka-shi, Osaka Fukuda Seiko Co., Ltd.

Claims (1)

[Claims] 1. A stopper is attached to a predetermined position of a high-voltage power cable, which is sandwiched and rotated by a circular cutting tool to rotate the sheath into slices. Then, a replacement die held by a die rotating tool is fitted to the tip of the sheath and rotated. With the peeling blade, the sheath is spirally cut to the sliced portion and stripped off, a stripping band is attached to the shield copper on the upper end of the sheath, the shield copper above it is cut off with a vertical cutting tool, and then on the sheath top. Replacing the stopper, sandwiching it with the circular cutting tool with the smaller inner diameter on its upper surface and rotating it to slice the outer semiconductive layer and peeling off the upper part, stopping the stopper at a predetermined position of the exposed insulator,
Fit the replacement die, which was replaced with a die-turner, onto the tip of the insulator, rotate it, and with the peeling blade, spirally cut the insulator to the stopper part and peel it off, chamfer the upper end of the insulator, and then conductor it according to the specified dimensions. A method of stripping a high-voltage power cable connection part, characterized by stripping the insulator, the outer semiconductive layer, the shielding copper, and the sheath.