CN203813397U - Middle voltage power cable middle joint vertical water stopping device - Google Patents

Abstract

The utility model relates to a longitudinal water-blocking device for an intermediate joint of a medium-voltage power cable, which solves the problem that none of the existing intermediate joints of the medium-voltage power cable has longitudinal water-blocking capability. The utility model adopts copper braided mesh to restore the cable copper shield at the joint, uses copper braid to restore the cable steel armor at the joint, uses a butt joint to realize the conductor connection, uses a stress cone to restore the connection between the inner and outer semiconducting and insulating, and uses the first waterproof sleeve, The second waterproof sleeve and the three-finger sleeve realize three-layer longitudinal water resistance, and the waterproof layers are all airtightly connected, and a copper mesh layer and an additional layer of armor are set on the outside of the copper braid to restore the copper shielding and armor of the cable. Layers. The utility model is suitable for being used as a water blocking device for an intermediate joint of a medium-voltage power cable.

Description

Longitudinal water blocking device for intermediate joints of medium voltage power cables

technical field

The invention relates to a longitudinal water blocking device for an intermediate joint of a medium-voltage power cable.

Background technique

At present, the intermediate joints of 10kV and 20kV medium-voltage power cables at home and abroad do not have the ability to prevent water in the longitudinal direction. In production practice, there are a large number of directly buried power cables that cause water to enter the cable body due to damage or damage to the outer sheath. , the moisture entering the cable body penetrates or flows into the cable intermediate joint along the cable body, causing progressive joint failures such as the reduction of the insulation performance of the cable intermediate joint, aging of water branches, severe partial discharge, and breakdown of insulation discharge, leading to power outages. occur, which greatly affects the quality and reliability of power supply. In recent years, among the faults of 10kV cable intermediate joints in Harbin Power Supply Company, the faults caused by longitudinal water ingress in cable intermediate joints accounted for about 50%. The problem of vertical water ingress.

Contents of the invention

The utility model proposes a longitudinal water blocking device for the middle joint of the medium voltage power cable in order to solve the problem that none of the intermediate joints of the existing medium voltage power cables has the longitudinal water blocking capacity.

The medium-voltage power cable intermediate joint longitudinal water blocking device described in the utility model, the medium-voltage power cable includes a three-phase wire core, three main insulating layers, three semi-conductive layers, three copper shielding layers, an inner sheath, an armor The three main insulating layers are respectively coaxially coated on the outside of the three-phase conductor core; the three semi-conductive layers are respectively coaxially coated on the outside of the three main insulating layers; three copper shielding layers Coaxially coated on the outside of the three semi-conductive layers; the inner sheath is wrapped on the outside of the three copper shielding layers; the armored layer is wrapped on the outside of the inner sheath;

The water blocking device includes two copper braids, two constant force springs, two first waterproof covers, two second waterproof covers, two three-finger covers, three butt joints, three stress cones, and three pieces of copper Braided mesh, third waterproof layer, crimp sleeve, copper mesh layer and additional layer of armor;

The three butt joints are respectively socketed on the outside of the three-phase wire core joints of the two cables, the three stress cones are respectively socketed on the outside of the three semi-conductive layer joints of the two cables, and the three copper braided meshes are respectively Wrapped on the outside of the three copper shield joints of the two cables, the third waterproof layer is wrapped on the outside of the three copper braided meshes, and wraps the three copper braided meshes as a whole; the two three-finger sleeves are respectively Cover the three-phase wire cores of the two cables, and one end of the two three-finger sleeves is respectively airtightly connected with the two second waterproof sleeves, and the other ends of the two three-finger sleeves are respectively connected to the three-phase wire cores of the two cables. The three copper shielding layers are sealed; two constant force springs are respectively sleeved on the outer sides of the armor layers of the two cables, and one end of the two copper braids is respectively crimped in the two constant force springs, and the two copper braids The other end is fixedly connected by crimping sleeve;

The two first waterproof sleeves respectively seal the inner sheath, the armor layer and the constant force spring of the two cables; the two second waterproof sleeves are respectively placed on the outer sides of the two first waterproof sleeves;

The copper mesh layer will cover the outer sides of the two first waterproof sleeves and the two copper braids;

The additional layer of armor is wrapped on the outside of the copper mesh waterproof layer.

In the practical application of the utility model, the cable at the joint is first stripped and cut, as shown in Figure 1, the utility model adopts a copper braided mesh to restore the copper shield of the cable at the joint, uses a copper braid to restore the steel armor of the cable at the joint, and uses a pair of The connecting pipe realizes the conductor connection, uses the stress cone to restore the connection between the inner and outer semiconducting and insulating, and uses the first waterproof jacket, the second waterproof jacket and the three-finger jacket to realize three-layer longitudinal water blocking, and the waterproof layers are all airtightly connected, avoiding the The problem of moisture reverse osmosis, and the copper mesh layer and armor additional layer are set on the outside of the copper braid, which restores the copper shielding and armor layer of the cable, and effectively solves the problem that the existing medium-voltage power cable intermediate joints do not have longitudinal The problem of water blocking capacity has effectively improved the longitudinal waterproof capacity of the intermediate joint of the medium voltage power cable, and compared with the existing intermediate joint device of the medium voltage power cable, the longitudinal waterproof capacity has increased by 20% year-on-year.

Description of drawings

Figure 1 is a schematic diagram of cable stripping and cutting at the joint;

Figure 2 is a schematic diagram of the installation structure of the longitudinal water blocking device for the intermediate joint of the medium-voltage power cable described in the utility model;

Fig. 3 is a schematic diagram of the installation positions of the copper braid 8 and the constant force spring 9 described in Embodiment 1;

Fig. 4 is a schematic diagram of the installation position of the first waterproof case 10 described in the first embodiment;

Fig. 5 is a schematic diagram of the installation position of the second waterproof case 11 described in the first embodiment;

Fig. 6 is a schematic diagram of the installation position of the finger cot 12 described in the first embodiment;

FIG. 7 is a schematic diagram of the installation position of the connecting pipe 13 described in the first embodiment.

Detailed ways

Specific Embodiments 1. This embodiment will be described with reference to Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6 and Fig. The cable includes three-phase wire core 1, three main insulating layers 2, three semiconducting layers 3, three copper shielding layers 4, inner sheath 5, armor layer 6 and outer sheath 7; three main insulating layers 2 are respectively coaxially coated on the outside of the three-phase wire core 1; the three semi-conductive layers 3 are respectively coaxially coated on the outside of the three main insulating layers 2; the three copper shielding layers 4 are coaxially coated on the three The outer side of a semiconducting layer 3; the inner sheath 5 is wrapped on the outer side of three copper shielding layers 4; the armor layer 6 is wrapped on the outer side of the inner sheath 5;

The water blocking device includes two copper braids 8, two constant force springs 9, two first waterproof cases 10, two second waterproof cases 11, two three-finger cases 12, three butt joints 13, three A stress cone 14, three copper braided meshes 15, a third waterproof layer 16, a crimp sleeve 17, a copper mesh layer 18 and an additional armor layer 19;

The three butt joints 13 are respectively socketed on the outside of the three-phase wire core 1 joints of the two cables, and the three stress cones 14 are respectively socketed on the outside of the three semi-conductive layer 3 joints of the two cables. Copper braided nets 15 are respectively wound on the outsides of the three copper shielding layers 4 joints of the two cables, and the third waterproof layer 16 is wrapped on the outsides of the three copper braided nets 15, and the three copper braided nets 15 are wrapped as One whole; two three-finger sleeves 12 are set on the three-phase wire cores 1 of the two cables respectively, and one end of the two three-finger sleeves is respectively airtightly connected with two second waterproof sleeves 11, and the other end of the two three-finger sleeves One end is respectively sealed with the three copper shielding layers 4 of the three-phase conductor core 1 of the two cables; two constant force springs 9 are respectively sleeved on the outer sides of the armor layers 6 of the two cables, One end is respectively crimped in the two constant force springs 9, and the other ends of the two copper braids 8 are fixedly connected by crimping sleeves 17;

The two first waterproof casings 10 respectively seal the inner sheath 5, the armor layer 6 and the constant force spring 9 of the two cables; the two second waterproof casings 11 are placed on the outer sides of the two first waterproof casings 10 respectively;

The copper mesh layer 18 will be coated on the outer sides of the two first waterproof casings 10 and the two copper braids 8;

The additional layer of armor 19 is coated on the outside of the copper mesh waterproof layer 18 .

Specific embodiment 2. This embodiment is a further description of the medium-voltage power cable intermediate joint longitudinal water blocking device described in specific embodiment 1. The first waterproof cover 10, the second waterproof cover 11 and the finger cot 12 are all made of waterproof tape The bypass is realized.

Strip and cut the two ends of the cable to be made into the cable intermediate joint according to the required size (as shown in Figure 1), tie the copper braid and the armor layer with a constant force spring or copper wire, and the outer sheath and armor layer are broken. At the center, the outer sheath, armored layer, and inner sheath are crossed and repeatedly bypassed the gap between the three-phase cables with waterproof tape, hooked into the first waterproof jacket (first longitudinal water-blocking layer), and then waterproofed with cold shrinkage The second waterproof jacket (the second longitudinal water-blocking layer) passes through the three-phase cable longitudinally, wraps it on the outside of the first waterproof jacket, and repeatedly wraps the second waterproof jacket and the copper shielding joint of the three-phase cable with multi-layer wrapping tightly. Finger cot (the third longitudinal water blocking layer), and then after completing the crimping of the three-phase core conductors at both ends to restore the conductor connection, the stress cone of the sleeve to restore the connection between the inner and outer semiconducting and insulation, and the copper braided mesh to restore the copper shielding The connection of the three-phase cable after the copper shielding has been restored is tightly wrapped with waterproof tape for multiple layers to cover the second waterproof, and then the copper braids on both sides are crimped with pressure pliers, and the copper braid and the cable body are wrapped with waterproof tape The three layers are covered to 80mm on both sides of the copper braid, and finally the three layers are wrapped with armor tape to cover the waterproof tape, and the middle joint of the longitudinal water-blocking cable is completed.

Claims (2)

1. medium-pressure power cable transition joint longitudinal water-blocking device, medium-pressure power cable comprises three-phase conducting wire core (1), three main insulating layers (2), three semi-conductive layers (3), three copper shields (4), sheath (5), armour (6) and oversheath (7); Three main insulating layers (2) are coaxially coated on respectively the outside of three-phase conducting wire core (1); Three semi-conductive layers (3) are coaxially coated on respectively the outside of three main insulating layers (2); Three copper shields (4) are coaxially coated on respectively the outside of three semi-conductive layers (3); Sheath (5) is coated on the outside of three copper shields (4); Armour (6) is coated on the outside of sheath (5);

It is characterized in that, this waterproofing device comprises two copper braid over braids (8), two constant force springs (9), two the first waterproof jackets (10), two the second waterproof jackets (11), two tri-finger stalls (12), three butt tubes (13), three stress cones (14), three copper mesh grids (15), the 3rd watertight composition (16), pressure welding case (17), copper mesh layers (18) and armouring extra play (19);

Three butt tubes (13) are socketed in respectively the outside of three-phase conducting wire core (1) joint of two cables, three stress cones (14) are socketed in respectively the outside of three semi-conductive layers (3) joint of two cables, three copper mesh grids (15) are wrapped in respectively the outside of three copper shields (4) joint of two cables, the 3rd watertight composition (16) is coated on the outside of three copper mesh grids (15), and three copper mesh grids (15) are coated as a whole; Two tri-finger stalls (12) are enclosed within respectively on the three-phase conducting wire core (1) of two cables, and one end of two tri-finger stalls respectively with airtight connection of two the second waterproof jackets (11), two tri-finger stall other ends respectively with three copper shields (4) sealing of the three-phase conducting wire core (1) of two cables; Two constant force springs (9) are socketed in respectively the outside of two armature of cable layers (6), one end of two copper braid over braids (8) is crimped on respectively in two constant force springs (9), and the other end of two copper braid over braids (8) is fixedly connected with by pressure welding case (17);

Two the first waterproof jackets (10) are respectively by the sheath of two cables (5), armour (6) and constant force spring (9) sealing; Two the second waterproof jackets (11) are enclosed within respectively the outside of two the first waterproof jackets (10);

Copper mesh layers (18) will be coated on the outside of two the first waterproof jackets (10) and two copper braid over braids (8);

Armouring extra play (19) is coated on the outside of copper mesh watertight composition (18).

2. medium-pressure power cable transition joint longitudinal water-blocking device according to claim 1, is characterized in that, the first waterproof jacket (10), the second waterproof jacket (11) and fingerstall (12) all adopt adhesive waterproof tape solderless wrapped connection to realize.