CN117995468A - Intermediate cold-shrink cable accessory for crosslinked polyethylene insulated power cable - Google Patents

Abstract

The invention discloses an intermediate cold shrink cable accessory for cross-linked polyethylene insulated power cable, relates to the technical field of cold shrink cable accessories, comprises two symmetrically arranged power cables, the power cable is composed of an external cable sheath and three internal cable wires, characterized in that the cable sheath comprises an inner sheath layer, a steel belt armor and an outer sheath layer from the inside to the outside, and the cable wire comprises a conductor, an insulating layer, an insulating shielding layer and a copper shielding layer from the inside to the outside; a cold shrink middle piece is arranged between the two symmetrical conductors, a tinned copper mesh sleeve is arranged on the outside of the cold shrink middle piece, a shielding ground wire is arranged on one side of the tinned copper mesh sleeve, an inner insulating protective composite layer is arranged on the outside of the two inner sheath layers, an outer insulating protective composite layer is arranged on the outside of the inner insulating protective composite layer, and an armor belt is arranged on the outside of the outer insulating protective composite layer. The invention improves the electrical performance and electromagnetic shielding effect of the cable system, as well as the performance and maintainability of the cable system through multi-layer insulation and shielding protection.

Description

An intermediate cold shrink cable accessory for cross-linked polyethylene insulated power cable

Technical Field

The invention relates to the technical field of cold shrink cable accessories, in particular to an intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable.

Background technique

Cross-linked Polyethylene (XLPE) insulated power cable is a type of cable commonly used to transmit electricity. It is widely used in underground cable lines, underground cable channels, power substations, industrial facilities and buildings in power transmission and distribution systems. Cross-linked polyethylene is a polymer material that forms a three-dimensional network structure between its molecular chains through a special cross-linking process, which improves its resistance to electrical breakdown and thermal performance. This special insulating material can withstand power transmission under high temperature and high voltage conditions, reducing the risk of wire insulation aging. At the same time, XLPE insulated cables have excellent heat resistance and can operate in high temperature environments without softening or deformation. Therefore, XLPE insulated cables are widely used to transmit high-voltage electricity, including power transmission between substations, urban power grids, underground cable lines, submarine cables, industrial facilities, and power distribution systems inside buildings.

In the cross-linked polyethylene insulated power cable system, the intermediate cold shrink cable accessories are an important component used to connect, maintain and insulate the cable, and are usually used in the middle of the cable to ensure the reliability and safety of the cable system. The main function of the intermediate cold shrink cable accessories is to provide cable connection, insulation and protection to prevent damage, contamination and electrical failure of the cable connection point.

Cold shrink parts are usually made of silicone material. They are pre-expanded and placed in a support tube to expand and deform. During installation, the support tube is extracted so that it can be wrapped around the installation position by its own elasticity. It does not need to be deformed by flame heating. This is called "cold shrinkage". Traditional medium-pressure cold shrink straight-through joints (important main products of intermediate accessories) are usually a combination of stress cones, conductive tubes, insulation layers, and outer shielding layers. Generally, silicone rubber products themselves do not have sufficient mechanical protection capabilities and may be susceptible to mechanical damage, such as physical impact or extrusion, which may damage the silicone body. The design or installation of the shielding layer is not sufficient to provide the necessary electromagnetic shielding effect. The cable may be susceptible to external electromagnetic interference, which may affect its performance. Improper grounding or failure of the shielding layer may cause grounding problems in the cable system, causing electrical failures or dangers.

Currently, no effective solution has been proposed for the problems in the related technologies.

Summary of the invention

In view of the problems in the related art, the present invention proposes an intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable to overcome the above technical problems existing in the existing related art.

To this end, the specific technical solution adopted by the present invention is as follows:

An intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable comprises two symmetrically arranged power cables, the power cable being composed of an outer cable sheath and three inner cable wires, and being characterized in that the cable sheath comprises an inner sheath layer, a steel belt armor and an outer sheath layer in sequence from the inside to the outside, and the cable wire comprises a conductor, an insulating layer, an insulating shielding layer and a copper shielding layer in sequence from the inside to the outside; a cold shrink middle piece is arranged between the two symmetrical conductors, a tinned copper mesh sleeve is sheathed on the outer side of the cold shrink middle piece, a shielded ground wire is arranged on one side of the tinned copper mesh sleeve, an inner insulating protective composite layer is sheathed on the outer side of the two inner sheath layers, an outer insulating protective composite layer is sheathed on the outer side of the inner insulating protective composite layer, and an armor belt is sheathed on the outer side of the outer insulating protective composite layer.

Furthermore, in order to ensure the cleanliness of the power cable itself to the greatest extent and avoid residual semi-conductive particles in the insulating area, a stripping process is used to strip the cable line into a multi-layer extended structure, which is helpful for the installation and implementation of subsequent conductor connections. The cable line adopts a stripping process to strip the copper shielding layer, the insulating shielding layer and the insulating layer in turn, and the end faces of the insulating layer and the insulating shielding layer are chamfered using a notch chamfering process; the outer surface of the insulating layer and the outer surface of the insulating shielding layer are polished with emery cloth strips to remove the semi-conductive particles remaining on the outer surface of the insulating layer, and a semi-conductive wrapping tape is provided at the end face connection between the insulating shielding layer and the copper shielding layer.

Furthermore, in order to utilize conductor connections, semi-conductive tapes, cold shrinkable intermediate bodies and inner waterproof insulating composite tapes to achieve reliable connection and insulation between conductors, semi-conductive tapes and inner waterproof insulating composite tapes are added to the outside of the insulating shielding layer, which effectively improves the electrical performance, shielding capability and waterproof performance of the cable system, and ensures the reliability, safety and environmental resistance of the cable connection points. The cold shrinkable intermediate piece includes a conductor connection arranged between two symmetrical conductors, a semi-conductive tape is provided on the outside of the conductor connection, a cold shrinkable intermediate body is provided on the outside of the semi-conductive tape, and inner waterproof insulating composite tapes are provided at both ends of the cold shrinkable intermediate body. The conductor connection completely covers the two conductors, both ends of the semi-conductive tape extend to the outside of the insulating layer, and the inner waterproof insulating composite tape is located on the outside of the insulating shielding layer.

Furthermore, in order to ensure the safety and performance stability of the cable system, inner constant force spring coils are provided at both ends of the tinned copper mesh sleeve, both ends of the shielded ground wire are located on the inner side of the circumference of the inner constant force spring coil, a PVC tape ring is provided on the outer side of the circumference of the inner constant force spring coil, and an intermediate tape ring is provided in the middle position between the tinned copper mesh sleeve and the shielded ground wire.

Furthermore, in order to effectively provide double insulation and waterproof protection for the cable, waterproof sealant is arranged at both ends of the inner layer and the outer layer of the inner insulation protection composite layer, and an armored ground wire is arranged between the outer layer of the inner insulation protection composite layer and the inner layer of the outer insulation protection composite layer, thereby further enhancing the waterproof performance and electromagnetic shielding effect of the cable system. This helps to ensure the reliability and stability of the cable system in a humid environment and reduce the impact of external interference. The inner insulation protection composite layer and the outer insulation protection composite layer are both double-layer structures, and the inner layers of the inner insulation protection composite layer and the outer insulation protection composite layer are both PVC tape layers, and the outer layers are both waterproof insulation composite tape layers. Waterproof sealant is arranged at both ends of the inner layer and the outer layer of the inner insulation protection composite layer, and an armored ground wire is arranged between the outer layer of the inner insulation protection composite layer and the inner layer of the outer insulation protection composite layer.

Furthermore, in order to enhance the mechanical protection of the cable and the connection stability between the insulation layers, the external constant force spring coil provides a reliable ground wire connection to ensure the grounding performance of the cable system, while the sealing PVC tape helps prevent external moisture and contaminants from entering the cable system, thereby maintaining the reliability and long-term performance of the cable, and jointly improving the anti-interference, mechanical protection and maintainability of the cable system. External constant force spring coils are provided at both ends of the armored ground wire, and the external constant force spring coils are located between the inner insulation protection composite layer and the outer insulation protection composite layer. The two ends of the armor belt are respectively located on the outside of the two outer sheath layers, and sealing PVC tapes are provided on the outside of both ends of the armor belt.

The beneficial effects of the present invention are:

1. Through the multi-layer composite design, the cable line has been given multi-layer insulation and shielding protection repair, which improves the electrical performance and electromagnetic shielding effect of the cable system. At the same time, the design of cold shrink middleware and conductor connection, semi-conductive tape, and inner waterproof insulation composite tape helps to achieve reliable connection and insulation between conductors, improves the performance and maintainability of the cable system, and ensures the integrity of the cable connection.

2. By adopting the stripping process, chamfering and grinding process, the semi-conductive particles remaining in the insulating area can be effectively removed, thereby improving the cleanliness of the insulating area and ensuring the insulation quality of the cable. On this basis, through the configuration of tinned copper mesh, shielded ground wire, semi-conductive tape, inner waterproof insulating composite tape, etc., the influence of external electromagnetic interference on the cable system is effectively reduced, and the waterproof performance of the cable system is increased.

3. By configuring external constant force spring coils, sealing PVC tape, armored ground wire and other structures at the connection point, the mechanical protection and grounding system of the cable are enhanced, and the stability and anti-interference of the cable system are improved.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

1 is a schematic cross-sectional view of an intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable according to an embodiment of the present invention;

FIG2 is a partial enlarged view of point A in FIG1;

3 is a schematic structural diagram of three cable wires of a power cable in an intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable before being stripped according to an embodiment of the present invention;

4 is a schematic structural diagram of three cable wires of a power cable in an intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable after stripping according to an embodiment of the present invention;

FIG5 is a partial enlarged view of point B in FIG4;

6 is a schematic structural diagram of two power cables in an intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable according to an embodiment of the present invention after being connected by a cold shrink intermediate piece.

In the figure:

1. Inner sheath layer; 2. Steel belt armor; 3. Outer sheath layer; 4. Conductor; 5. Insulation layer; 6. Insulation shielding layer; 7. Copper shielding layer; 8. Cold shrinkage middle piece; 801. Conductor connection; 802. Semi-conductive tape; 803. Cold shrinkage middle body; 804. Inner waterproof insulation composite tape; 9. Tinned copper mesh; 10. Shielded ground wire; 11. Inner insulation protection composite layer; 12. Outer insulation protection composite layer; 13. Armor belt; 14. Semi-conductive wrapping tape; 15. Inner constant force spring coil; 16. PVC tape coil; 17. Middle tape coil; 18. Waterproof sealant; 19. Armored ground wire; 20. Outer constant force spring coil; 21. Sealing PVC tape.

Detailed ways

To further illustrate each embodiment, the present invention provides drawings, which are part of the disclosure of the present invention and are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, ordinary technicians in the field should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

According to an embodiment of the present invention, an intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable is provided.

The present invention is now further described in conjunction with the accompanying drawings and specific embodiments. As shown in Figures 1 to 6, an intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable according to an embodiment of the present invention comprises two symmetrically arranged power cables, which are composed of an external cable sheath and three internal cable wires, and are characterized in that the cable sheath comprises an inner sheath layer 1, a steel belt armor 2 and an outer sheath layer 3 from the inside to the outside, and the cable wire comprises a conductor 4, an insulating layer 5, an insulating shielding layer 6 and a copper shielding layer 7 from the inside to the outside; a cold shrink middle piece 8 is arranged between the two symmetrical conductors 4, a tinned copper mesh sleeve 9 is provided on the outside of the cold shrink middle piece 8, a shielded ground wire 10 is provided on one side of the tinned copper mesh sleeve 9, an inner insulating protective composite layer 11 is provided on the outside of the two inner sheath layers 1, an outer insulating protective composite layer 12 is provided on the outside of the inner insulating protective composite layer 11, and an armor belt 13 is provided on the outside of the outer insulating protective composite layer 12.

With the help of the above technical solution, through a multi-layer composite design, the cable line is given multi-layer insulation and shielding protection repair, which improves the electrical performance and electromagnetic shielding effect of the cable system. At the same time, the design of the cold shrink middle piece 8 helps to achieve reliable connection and insulation between conductors, improves the performance and maintainability of the cable system, and ensures the integrity of the cable connection.

In one embodiment, for the above-mentioned cable line, the cable line adopts a stripping process to sequentially strip the copper shielding layer 7, the insulating shielding layer 6 and the insulating layer 5, and the end faces of the insulating layer 5 and the insulating shielding layer 6 are chamfered by a notch chamfering process; the outer surface of the insulating layer 5 and the outer surface of the insulating shielding layer 6 are polished with a 400-mesh sandpaper strip to remove the semi-conductive particles remaining on the outer surface of the insulating layer 5, and the end surface connection of the insulating shielding layer 6 and the copper shielding layer 7 is provided with a semi-conductive wrapping tape 14, so as to ensure the cleanliness of the power cable itself to the greatest extent and avoid the residual semi-conductive particles in the insulating area. The cable line is stripped into a multi-layer extended structure by a stripping process, which is helpful for the installation and implementation of subsequent conductor connections.

In one embodiment, for the above-mentioned cold shrink middle piece 8, the cold shrink middle piece 8 includes a conductor connection 801 (standard name: connecting tube) arranged between two symmetrical conductors 4, a semi-conductive tape 802 is sleeved on the outside of the conductor connection 801, a cold shrink middle body 803 is sleeved on the outside of the semi-conductive tape 802, and inner waterproof insulating composite tape 804 is arranged at both ends of the cold shrink middle body 803. The conductor connection 801 completely covers the two conductors 4, and both ends of the semi-conductive tape 802 extend to the outside of the insulating layer 5. The inner waterproof insulating composite tape 804 is located on the outside of the insulating shielding layer 6, so that the conductor connection 801, the semi-conductive tape 802, the cold shrink middle body 803 and the inner waterproof insulating composite tape 804 can be used to achieve reliable connection and insulation between the conductors 4. At the same time, the semi-conductive tape 802 and the inner waterproof insulating composite tape 804 are added to the outside of the insulating shielding layer 6, which effectively improves the electrical performance, shielding capability and waterproof performance of the cable system, and ensures the reliability, safety and environmental resistance of the cable connection point.

In one embodiment, for the above-mentioned tinned copper mesh sleeve 9, both ends of the tinned copper mesh sleeve 9 are provided with inner constant force spring coils 15, both ends of the shielding ground wire 10 are located on the inner side of the circumference of the inner constant force spring coil 15, and the outer side of the circumference of the inner constant force spring coil 15 is provided with a PVC tape ring 16, and the middle position of the tinned copper mesh sleeve 9 and the shielding ground wire 10 is provided with an intermediate tape ring 17, thereby ensuring the safety and performance stability of the cable system.

In one embodiment, for the above-mentioned inner insulating protective composite layer 11, the inner insulating protective composite layer 11 and the outer insulating protective composite layer 12 are both double-layer structures, and the inner layers of the inner insulating protective composite layer 11 and the outer insulating protective composite layer 12 are both PVC tape layers, and the outer layers are both waterproof insulating composite tape layers, and waterproof sealants 18 are provided at both ends of the inner layer and the outer layer of the inner insulating protective composite layer 11, and an armored ground wire 19 is provided between the outer layer of the inner insulating protective composite layer 11 and the inner layer of the outer insulating protective composite layer 12, thereby effectively providing double insulation and waterproof protection for the cable line. At the same time, by providing waterproof sealants 18 at both ends of the inner layer and the outer layer of the inner insulating protective composite layer 11, and providing an armored ground wire 19 between the outer layer of the inner insulating protective composite layer 11 and the inner layer of the outer insulating protective composite layer 12, the waterproof performance and electromagnetic shielding effect of the cable system are further enhanced, which helps to ensure the reliability and stability of the cable system in a humid environment and reduce the impact of external interference.

In one embodiment, for the above-mentioned armored ground wire 19, both ends of the armored ground wire 19 are provided with external constant force spring coils 20, and the external constant force spring coils 20 are located between the inner insulating protection composite layer 11 and the outer insulating protection composite layer 12, and the two ends of the armor belt 13 are respectively located on the outside of the two outer sheath layers 3, and the outsides of both ends of the armor belt 13 are provided with sealing PVC tapes 21, thereby enhancing the mechanical protection of the cable and the connection stability between the insulation layers. The external constant force spring coil 20 provides a reliable ground wire connection to ensure the grounding performance of the cable system, and the sealing PVC tape 21 helps to prevent external moisture and contaminants from entering the cable system, thereby maintaining the reliability and long-term performance of the cable, and jointly improving the anti-interference, mechanical protection and maintainability of the cable system.

In order to facilitate understanding of the above technical solutions of the present invention, the working principle or operation mode of the present invention in the actual process is described in detail below.

In actual application, the installation is carried out on the basis of two power cables according to the installation procedure. The specific operation procedures are as follows: preparation work → stripping off the outer sheath layer 3 and steel tape armor 2 of the cable → stripping off the copper shielding layer 7 and the insulating shielding layer 6 of the cable → stripping off the insulating layer 5 and chamfering → installing the cold shrink straight-through joint body (cold shrink middle piece 8) → installing the cold shrink straight-through joint body → waterproofing repair and semi-conductive layer repair at both ends of the middle body → repairing the copper shielding layer 7 (installing the inner constant force spring ring 15 and the PVC tape ring 16) → winding the inner insulating protective composite layer 11 → installing the armored ground wire 19 (the armored ground wire 19 has outer constant force spring rings 20 on both sides to keep it fixed) → winding the outer insulating protective composite layer 12 → winding the armor belt 13.

In summary, with the aid of the above technical solution of the present invention, through the multi-layer composite design, the cable line is provided with multi-layer insulation and shielding protection repair, the electrical performance and electromagnetic shielding effect of the cable system are improved, and the design of the cold shrink middle piece 8 is helpful to achieve reliable connection and insulation between conductors, improve the performance and maintainability of the cable system, and ensure the integrity of the cable connection. By adopting the stripping process, chamfering and grinding process, the semi-conductive particles remaining in the insulation area are effectively removed, thereby improving the cleanliness of the insulation area and ensuring the insulation quality of the cable. On this basis, the tinned copper mesh sleeve 9, the shielded ground wire 10, the semi-conductive tape 802, the inner waterproof insulation composite tape 804 and other configurations are used to effectively reduce the influence of external electromagnetic interference on the cable system, and at the same time increase the waterproof performance of the cable system. By configuring the external constant force spring coil 20, the sealing PVC tape 21, the armored ground wire 19 and other structures at the connection, the mechanical protection and grounding system of the cable are enhanced, and the stability and anti-interference of the cable system are improved.

In the present invention, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. The utility model provides a cross-linked polyethylene insulating power cable is with middle shrinkage cable accessory, includes two power cable that symmetry set up, this power cable comprises outside cable sheath and inside three cable conductor, its characterized in that, the cable sheath includes inner sheath layer (1), steel band armour (2) and oversheath layer (3) from inside to outside in proper order, the cable conductor includes conductor (4), insulating layer (5) insulating shield layer (6) and copper shield layer (7) from inside to outside in proper order;

Be provided with shrinkage middleware (8) between two symmetries conductor (4), shrinkage middleware (8) outside cover is equipped with tinned copper net cover (9), tinned copper net cover (9) one side is provided with shielding ground wire (10), two the cover is equipped with interior insulation protection composite layer (11) in inner sheath layer (1) outside, the cover is equipped with outer insulation protection composite layer (12) in the outer cover of interior insulation protection composite layer (11), outer insulation protection composite layer (12) outside cover is equipped with armor tape (13).

2. The intermediate cold shrink cable accessory for a crosslinked polyethylene insulated power cable according to claim 1, wherein the cable sequentially strips the copper shielding layer (7), the insulating shielding layer (6) and the insulating layer (5) by adopting a stripping process, and the end surfaces of the insulating layer (5) and the insulating shielding layer (6) are chamfered by adopting a notch chamfering process;

The outer surface of the insulating layer (5) and the outer surface of the insulating shielding layer (6) are polished by using 400-mesh abrasive cloth strips, and the abrasive cloth strips are used for removing semiconductive particles remained on the outer surface of the insulating layer (5).

3. An intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable according to claim 1 or 2, characterized in that the end surface connection of the insulating shielding layer (6) and the copper shielding layer (7) is sleeved with a semi-conductive wrapping tape (14).

4. The middle cold-shrink cable accessory for the crosslinked polyethylene insulated power cable according to claim 1, wherein the cold-shrink intermediate piece (8) comprises a conductor connection (801) arranged between two symmetrical conductors (4), a semi-conductive belt (802) is sleeved outside the conductor connection (801), a cold-shrink intermediate body (803) is sleeved outside the semi-conductive belt (802), and inner waterproof insulating composite adhesive tapes (804) are arranged at two ends of the cold-shrink intermediate body (803).

5. An intermediate cold shrink cable attachment for a cross-linked polyethylene insulated power cable according to claim 4, characterized in that the conductor connection (801) completely covers both conductors (4), both ends of the semiconductive tape (802) extend outside the insulating layer (5), the inner waterproof insulating composite tape (804) being located outside the insulating shielding layer (6).

6. The middle cold-shrink cable accessory for the crosslinked polyethylene insulated power cable according to claim 1, wherein inner constant force spring rings (15) are arranged at two ends of the tinned copper mesh (9), two ends of the shielding ground wire (10) are located on the inner circumference of the inner constant force spring rings (15), PVC adhesive tape rings (16) are sleeved on the outer circumference of the inner constant force spring rings (15), and middle adhesive tape rings (17) are arranged at the middle positions of the tinned copper mesh (9) and the shielding ground wire (10).

7. The cold shrink cable accessory for a cross-linked polyethylene insulated power cable according to claim 1, wherein the inner insulation protection composite layer (11) and the outer insulation protection composite layer (12) are both of a double-layer structure, and the inner layers of the inner insulation protection composite layer (11) and the outer insulation protection composite layer (12) are both PVC tape layers, and the outer layers are both waterproof insulation composite tape layers.

8. The middle cold shrink cable accessory for the crosslinked polyethylene insulated power cable according to claim 1 or 7, wherein waterproof sealant (18) is arranged at two ends of the inner layer and the outer layer of the inner insulation protection composite layer (11), and an armored ground wire (19) is arranged between the outer layer of the inner insulation protection composite layer (11) and the inner layer of the outer insulation protection composite layer (12).

9. An intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable according to claim 8, characterized in that the armoured earth wires (19) are provided with outer constant force coils (20) at both ends, and the outer constant force coils (20) are located between the inner insulation protection composite layer (11) and the outer insulation protection composite layer (12).

10. An intermediate cold shrink cable accessory for a cross-linked polyethylene insulated power cable according to claim 1, wherein two ends of the armor tape (13) are respectively positioned outside the two outer sheath layers (3), and sealing PVC tapes (21) are respectively arranged outside the two ends of the armor tape (13).