CN201584211U

CN201584211U - Medium-voltage water-blocked power cable for nuclear power station

Info

Publication number: CN201584211U
Application number: CN200920241724XU
Authority: CN
Inventors: 陈虎啸; 肖克俭; 张文华
Original assignee: JIANGXI CABLE CO Ltd
Current assignee: JIANGXI CABLE CO Ltd
Priority date: 2009-12-11
Filing date: 2009-12-11
Publication date: 2010-09-15
Anticipated expiration: 2019-12-11

Abstract

The utility model relates to a medium-voltage water-blocked power cable for a nuclear power station, which comprises a conductor (1), a conductor shielding layer (2), a cross-linked polyethylene insulating layer (3), an insulation shielding layer (4), a semi-conductive water-blocked layer (5), a copper strip shielding layer (6), water-blocked rope fillers (7), a lapping water-blocked strip (8), an oxygen separating layer (9) and a dedicated low-smoke zero-halogen outer sheath (10) used for the nuclear power station, wherein the conductor (1) forms insulating cores by sequentially extruding and wrapping the conductor shielding layer, the cross-linked polyethylene insulating layer and the insulation shielding layer through three layers of coextrusion crosslinking machines; the three insulating cores form a cable in the right direction; the water-blocked rope fillers (7) are filled in the gaps and on the outer part of the insulating cores, and the lapping water-blocked strip (8) is wound around the insulating cores; the oxygen separating layer (9) is extruded and wrapped outside a cabling core; and an outer sheath wound around the outermost layer of a cable is the dedicated low-smoke zero-halogen outer sheath (10) used for the nuclear power station. The dedicated low-smoke zero-halogen outer sheath (10) used for the nuclear power station is made of low-smoke zero-halogen polyolefin materials. The medium-voltage water-blocked power cable is suitable for a medium-voltage distribution cable in the nuclear power station.

Description

Pressure drag hydroelectric power cable in the used in nuclear power station

Technical field

The utility model relates to pressure drag hydroelectric power cable in a kind of used in nuclear power station, belongs to the electrical material technical field.

Background technology

Used in nuclear power station 3.6/6～8.7/15kV1E level K3 class midium voltage cable is one of important auxiliary products of nuclear power station, is mainly used in electric power transfer in the nuclear power station.Because environment for use is special, therefore very high to the requirement of cables of nuclear power, cables of nuclear power also should possess following individual character or characteristic: 1. have excellent fire retardant except that general character that possesses general cable such as electric, mechanical, physical property, low cigarette (light transmittance is greater than 60%), Halogen etc.; 2. 40 years～60 years useful life; 3. can in the environment that humidity, ozone and oil are arranged, normally use; 4. Yan Ge nuclear safety quality assurance and Quality Identification.

For middle pressure power cable with cross-linked polyethylene insulation, following several stop water is arranged usually:

1. for single-core cable, wrapped semiconductive waterstop on the insulation screen of cable, at the wrapped common waterstop in metal screen layer outside, extrude oversheath then, for three-core cable then in order to guarantee the abundant contact of metallic shield, only at the wrapped semiconductive waterstop in insulation shielding outside, metallic shield is outward no longer around waterstop, look the height that water resistance requires, filling can be adopted common filling or the filling that blocks water, the same single-core cable of inner covering and jacket material;

2. indulge alclad plastic composite strip layer as watertight composition in the inside of oversheath or inner covering;

3. directly extrude the HDPE oversheath in the cable outside.

Nuclear power station is generally built coastal area in, because these regional weathers are moistening, air humidity is big, and this has influenced cable performance and useful life greatly.This mainly is that test data shows that water tree can cause local stress to increase, and may become the cradle of electric branch because easily form cable water tree in wet environment.Under the high temperature, in the water tree significant oxidation may take place, cause water absorption to increase, conductivity increases, final thermal breakdown; Even at low temperatures, water tree is through the long period oxidation or be converted into electric branch, also can cause the destruction of insulation.

When cable moved in wet environment for a long time, if there is not good waterproof construction, more to be easy to generate the water tree of insulation aging for cable so, thereby the destruction of causing insulation will be shortened life-span of cable so greatly.Therefore, development waterproofing type used in nuclear power station cable is necessary.

More existing power cables are used for general industry more, the disclosed a kind of water-resistant power cable of publication number CN2751415, and it comprises conductor, outer insulating barrier and the oversheath of conductor, is full of material water-proof material between this insulating barrier and the oversheath and fills; Publication number CN101071658 is disclosed to be a kind of waterproof power cable and manufacture method, this waterproof power cable is by three single cores cable twisting stranding that blocks water, and every single core cable that blocks water is made of conductor, the bisque that blocks water, screen, insulating barrier, insulation screen, semiconductor waterstop I, metal screen layer, semiconductor waterstop II, water blocking layer and external sheath layer from inside to outside successively.But above-mentioned cable can not adapt to nuclear power plant environment to be used.

Summary of the invention

The objective of the invention is,, propose a kind of nuclear power station electricity needs that both had been fit to, again pressure drag hydroelectric power cable new construction in the 1E level K3 class that can not damage in the medium-term and long-term work of wet environment according to the nuclear power station requirement.

Technical scheme of the present invention is that pressure drag hydroelectric power cable is filled the special-purpose low smoke and zero halogen oversheath of (7), wrapped waterstop (8), oxygen barrier layer (9) and nuclear power station (10) and formed by conductor (1), conductor shield (2), crosslinked polyetylene insulated layer (3), insulation screen (4), semiconductive water blocking layer (5), copper strips screen (6), waterproofing rope from the inside to the outside in the used in nuclear power station of the present invention; The conductor of cable (1) is for forming copper or stranded pressing of aluminium monofilament; Conductor extrudes conductor shield (2), crosslinked polyetylene insulated layer (3) and insulation screen (4) successively through the three-layer co-extruded cross-linking unit and forms insulated wire cores; Wrapped successively semiconductive waterstop (5) and copper strips screen (6) on insulated wire cores then; Three thoroughly do away with edge core dextrad stranding, fill waterproofing rope (7) in the gap and the outside of insulated wire cores, and wrapped thereon waterstop (8); Become cable core to extrude one deck oxygen barrier layer (9) outward again, the cable outermost layer is wrapped up in the low smoke and zero halogen oversheath (10) that multiple oversheath is the nuclear power station special use, and this low smoke and zero halogen oversheath is selected the low-smoke halogen-free polyolefin material for use.

The utility model decapacitation is satisfied the general kernel power station to outside the performance requirements such as cable electrical, physical and mechanical properties, low-smoke non-halogen flame-retardant, the most outstanding characteristics are to be provided with water blocking layer in the structure of cable, when cable uses in a humid environment, the water blocking layer imbibition also stops moisture content further to spread, stop it to the cable internal penetration, thereby anti-sealing tree form, and has improved the stability and the fail safe of nuclear power station supply line, prolong cable useful life, reduced power supply cost.

The utility model beneficial effect compared with the prior art is, pressure drag hydroelectric power cable can not only satisfy every requirement that nuclear power plant environment is used in the used in nuclear power station of the present invention, and owing to be provided with cable impervious layer, when being used in a humid environment, cable insulation avoid the water tree to produce, improve the fail safe and the reliability of cable operation, prolonged the useful life of cable.

The utility model is suitable for pressing in the nuclear power station transmission ﹠ distribution cable to use.

Description of drawings

Accompanying drawing is a product structure schematic diagram of the present utility model.

Picture in picture number expression: (1) conductor; (2) conductor screen; (3) crosslinked polyetylene insulated layer; (4) insulation screen; (5) semiconductive water blocking layer; (6) copper strips screen; (7) filling that blocks water; (8) wrapped waterstop; (9) oxygen barrier layer; (10) the special-purpose low smoke and zero halogen oversheath of nuclear power station.

Embodiment

The utility model embodiment is example with the three-core cable, and as shown in Figure 1, the conductor of cable is to form stranded pressing of copper monofilament (1); Conductor extrudes conductor screen (2), crosslinked polyetylene insulated layer (3) and insulation screen (4) successively through the three-layer co-extruded cross-linking unit; Wrapped successively semiconductive waterstop (5) and copper strips (6) on the insulated wire cores; Three thoroughly do away with edge core dextrad stranding, fill waterproofing rope (7) in the gap and the outside of insulated wire cores, and wrapped thereon waterstop (8); Become cable core to extrude one deck oxygen barrier layer (9) outward, the cable outermost layer is wrapped up in the low smoke and zero halogen oversheath (10) that multiple oversheath is the nuclear power station special use, and the low smoke and zero halogen oversheath is the low-smoke halogen-free polyolefin material of nuclear power station special use.Finished cable is that the referable user uses through exfactory inspection.

Claims

1. pressure drag hydroelectric power cable in the used in nuclear power station, it is characterized in that described power cable is filled the special-purpose low smoke and zero halogen oversheath of (7), wrapped waterstop (8), oxygen barrier layer (9) and nuclear power station (10) and formed by conductor (1), conductor shield (2), crosslinked polyetylene insulated layer (3), insulation screen (4), semiconductive water blocking layer (5), copper strips screen (6), waterproofing rope from the inside to the outside; Described conductor (1) extrudes conductor shield (2), crosslinked polyetylene insulated layer (3) and insulation screen (4) successively through the three-layer co-extruded cross-linking unit and forms insulated wire cores; Three thoroughly do away with edge core dextrad stranding, fill waterproofing rope (7) in the gap and the outside of insulated wire cores, and wrapped thereon waterstop (8); Become cable core to extrude one deck oxygen barrier layer (9) outward again, the cable outermost layer is wrapped up in the low smoke and zero halogen oversheath (10) that multiple oversheath is the nuclear power station special use.

2. pressure drag hydroelectric power cable is characterized in that in the used in nuclear power station according to claim 1, and described low smoke and zero halogen oversheath (10) is selected the low-smoke halogen-free polyolefin material for use.