CN200950364Y

CN200950364Y - Single-core power cable

Info

Publication number: CN200950364Y
Application number: CN 200620010032
Authority: CN
Inventors: 丁振生; 张涛
Original assignee: QINGDAO HANHE CABLE GROUP CO Ltd
Current assignee: Qingdao Hanhe Cable Co., Ltd.
Priority date: 2006-09-18
Filing date: 2006-09-18
Publication date: 2007-09-19
Anticipated expiration: 2016-09-18

Abstract

The utility model discloses a single-core power cable. The cable core consists of a copper conductor (1), a conductor shielding layer (2), an insulation layer (3) and an insulation shielding layer (4); the cable core is wrap with a metal shielding layer (5), and covered with an external extruded sheath (6); wherein the metal shielding layer (6) is made of lengthwise metal jacketed strips, in which a minimum of 6mm in width is provided for the lapping between the metal jacketed strips and an adhesive layer is arranged for securing joints; a waterproof buffering layer (5) is provided between the cable core (1) and the metal shielding layer (6). The utility model can effectively improve the short-circuit withstand ability of the cable shielding and meet the short-circuit demands of a direct grounding or a small-resistance grounding, enhance the water resistance in radial and lengthwise directions, eliminate the adverse influences on the cable caused by thermal expansion and cold contraction due to temperature variation, avoid the mechanical damages of the insulation shielding layer caused by the covered metal shielding layer, thereby improving the safety of cable manufacturing and running and extending the service life of the power cable.

Description

Single-core power cables

Affiliated technical field

The utility model relates to a kind of structure of power cable, is a kind of improvement of single-core power cables structure specifically.

Background technology

Usually employed power cable in power distribution network or industrial equipment, generally by the core of conductive copper wire core, conductor shield, insulating barrier and cable that insulation screen is formed, the wrapped metal screen layer of external spiral extrudes sheath then and constitutes.The power cable of this structure because the wrapped metallic shield layer process of spiral, has limited metal screen layer, i.e. the width of copper strips, and the short-circuit capacity of cable shield is smaller, can not satisfy the short circuit requirement of direct ground connection or low resistance grounding system; And, the wrapped metallic shield layer process of this spiral, can't solve metal screen layer, be the bonding closed-ended question of overlapping the slot place that in wrapped process, occurs of copper strips, cause power cable under the situation that the power cable sheath sustains damage, can not effectively block water, in the use of cable, cause the power cable into water that makes moist easily, influence is normally used, and reduces its working life.Before the utility model design is finished, not seeing the power cable identical with the utility model structure as yet uses in power distribution network and industrial equipment, not seeing the power cable identical with the utility model structure has sale on market, it is on the books in the literature also not see the power cable identical with the utility model structure.

Summary of the invention

The purpose of this utility model is to provide a kind of single-core power cables, can effectively improve the short-circuit capacity of cable shield, can satisfy the short circuit requirement of direct ground connection and low resistance grounding system, strengthen cable radially, water-resisting ability longitudinally, eliminate because variation of temperature, the harmful effect that cable material is produced expand with heat and contract with cold and cable is produced, solve the mechanical damage of wrapped metal screen layer, improve the fail safe of cables manufacturing, operation and prolong useful life of power cable insulation screen.

For achieving the above object, the utility model adopts following technical proposals:

A kind of single-core power cables, core by conductive copper wire core, conductor shield, insulating barrier and cable that insulation screen is formed, core has metal screen layer outward, it is outer for extruding sheath, said metal screen layer is vertical clad metal band, the seam lap width is not less than 6mm between metal tape and the metal tape, and seam crossing has adhesive linkage bonding, is provided with water-blocking buffer layer between conductive copper wire core and metal screen layer.

In technique scheme, said metal screen layer is through the copper strips of embossing or compound copper-plastics band.

In technique scheme, said seam crossing adhesive linkage is that PUR or tack compound copper-plastics band are bonded in the technique scheme, and said water-blocking buffer layer is the semiconductive zone of swelling that blocks water.

The utility model has effect described below and good effect:

1, the metal screen layer of single-core power cables by wrapped change vertical bag into after, the short-circuit capacity of the cable shield of the identical copper strips thickness of same cable specification can increase more than 3 times.

Table 1 is that Qingdao Chinese cable group company technique center is the contrast of the shielding of the wrapped copper strips of different size 35kv single-core crosslinked cable and the calculating cross section of indulging the shielding of copper-clad band and measured short-circuit current value (regulation of IEC949-88 is pressed in the calculating cross section of copper strips).

Table 1

Nominal cross mm ²	Core external diameter mm	Wrapped copper strips area mm ²	The long-pending mm of vertical copper-clad zone face ²	Wrapped short circuit current A/1s	Vertical bag short circuit current A/1s
Nominal cross mm ²	Core external diameter mm	Wrapped copper strips area mm ²	The long-pending mm of vertical copper-clad zone face ²	Wrapped short circuit current A/1s	Vertical bag short circuit current A/1s	50	33.3	4.2	13.7	882	2877
70	34.6	4.2	14.2	882	2982	50	33.3	4.2	13.7	882	2877
70	34.6	4.2	14.2	882	2982	95	36.2	4.2	14.8	882	3108
120	37.6	4.2	15.3	882	3213	95	36.2	4.2	14.8	882	3108
120	37.6	4.2	15.3	882	3213	150	39.2	4.8	15.9	1008	3339
185	40.8	4.8	16.5	1008	3465	150	39.2	4.8	15.9	1008	3339
185	40.8	4.8	16.5	1008	3465	240	43.0	4.8	17.4	1008	3654
300	45.2	4.8	18.2	1008	3822	240	43.0	4.8	17.4	1008	3654
300	45.2	4.8	18.2	1008	3822	400	48.8	4.8	19.6	1008	4116

2, after vertical pack arrangement was adopted in metallic shield, the radially water-resisting ability of cable strengthened greatly.The minimum width of putting up that 6mm is arranged of vertical copper-clad band shielding, the copper strips seam is bonding with PUR, forms the metal tube of a sealing.Metal tube is integral with the plastics oversheath is bonding again, if moisture by plastics oversheath endosmosis, will be prevented from when arriving metallic sheath, has only from the overlap joint mouth and inwardly spreads by PUR along overlapping the slot.But the permeation pathway lengthening, permeable area is small, and shipwreck has improved the radially water-resisting ability of cable to infiltrate, and cable is suitable for direct-burried and moist operational environment.

3, after vertical bag was adopted in metallic shield, cable can be realized vertically blocking water.Add material water-proof material between insulation shielding and metallic shield, this material imbibition stops moisture vertically to connect along insulating surface, and restriction moisture continues to enter, and makes into that the water degree is restricted in the minimum scope, improves the reliability and the recoverability of cable.

4, vertical genus shielding covered with gold leaf can be eliminated cable because of variations in temperature, and the harmful effect that material expands with heat and contract with cold cable is produced is as 35kv 95mm ²Single-core crosslinked cable, the about 36.2mm of the external diameter of insulation shielding in the time of 20 ℃, when temperature is elevated to 90 ℃, the insulation shielding external diameter may expand to 37.42mm, and the linear expansion amount of wrapped copper strips this moment on circumference only has 0.135mm, can't satisfy the thermal expansion requirement of insulating barrier, force insulating barrier distortion or copper strips to produce irreversible elongation, influence the normal operation of cable.Vertical genus shielding covered with gold leaf has a water-blocking buffer layer between insulation shielding and metal tape, the influence of thermal expansion to cable eliminated in the gap between may command copper strips and insulation shielding on the technology simultaneously.

5, can eliminate the mechanical damage of wrapped copper strips to insulation shielding, wrapped copper strips shielding is general direct wrapped on insulated wire cores, around-packing technology has determined that copper strips applies bigger wrapped power to core when wrapped, improper or the copper strips generation fold when lapping angle, be easy to damage insulated wire cores, on technology, eliminate the possibility of damaging core and indulge the shielding of gold filled genus fully, guaranteed the fail safe in cable design manufacturing, the running.

Description of drawings

Below in conjunction with drawings and Examples structure of the present utility model is done explanation in further detail:

Fig. 1 is the structural representation of the utility model embodiment 1.

The 1st, conductive copper wire core, the 2nd, conductor shield, the 3rd, insulating barrier, the 4th, insulation screen, the 5th, water-blocking buffer layer, the 6th, metal screen layer, the 7th, sheath.

Embodiment

Embodiment 1:

A kind of rated voltage 35kV and following crosslinked polyetylene insulated vertical covered with gold leaf genus of being produced by QingDao HanLan Group Co., Ltd shield single-core cable, it is by conductive copper wire core (1), conductor shield (2), insulating barrier (3), insulation screen (4) is formed the core of cable, one deck water-blocking buffer layer (5) is arranged between core and the metal screen layer (6), the outer sheath (7) that extrudes of metal screen layer (6), said metal screen layer (6) forms through the vertical bag of special technology for the copper strips through embossing, seam has the bonding layer of PUR, seam crossing copper strips lap width is 6.5mm, the thickness 0.12mm of copper strips, between conductive copper wire core (1) and the metal screen layer (6) one deck water-blocking buffer layer (5) is arranged, be the semiconductive zone of swelling that blocks water, thickness is 0.6mm.

Claims

1, a kind of single-core power cables, the core of being formed cable by conductive copper wire core (1), conductor shield (2), insulating barrier (3) and insulation screen (4), core has metal screen layer (5) outward, it is outer for extruding sheath (6), it is characterized in that said metal screen layer (6) is vertical clad metal band, the seam lap width is not less than 6mm between metal tape and the metal tape, seam crossing has adhesive linkage bonding, is provided with water-blocking buffer layer (5) between conductive copper wire core (1) and metal screen layer (6).

2, single-core power cables according to claim 1 is characterized in that said metal screen layer (6) is copper strips or compound copper-plastics band through embossing.

3, single-core power cables according to claim 1 is characterized in that said seam crossing adhesive linkage is PUR or tack compound copper-plastics band adhesive linkage.

4, single-core power cables according to claim 1 is characterized in that said water-blocking buffer layer (5) is the semiconductive zone of swelling that blocks water.