Power cable fault repair
cable failure occurs, should according to the failure type and failure properties, the corresponding repair measures, in order to avoid failure to further expand, accidents caused by cable. Common troubleshooting can be divided into oil leakage fault repair, corona discharge cable fault repair, cable flashover failure repair skin repair, cable, cable insulation damage lead crack fault repair, cable outer sheath fault repair a total of six categories.
cable oil leakage fault repair
due to various reasons, cause lead ( Aluminum) Rupture, or crack, to make the cable oil spill, oil leakage cable, can make the oil pressure reduced in the cable, cause the loss of high cable insulation oil deficiency, serious can make the air and water immersion, and insulation breakdown caused by accidents. The common welding repair methods are divided into lead leakproof method, steel sleeve sealing method, epoxy fill oil, now the points mentioned below.
1, lead welding leakproof method ( Apply to power failure conditions)
(1) the cable oil pressure switch to allow Min ( For oil filled cable) 。
2. Stripped of leakage point kai packed layer, outer covering, such as copper tape, waterproof layer, layer exposed lead after leaking fissure, dip in with cotton ball cable oil layer surface wipe the lead.
(3) according to the lead plane leaking fissure size, intercepting the appropriate size of the lead, lead a bare skin, and drill a hole on it.
seal lead electrode with sealing. Copper lead sheathed outside diameter about a large set of diameter of 30 mm, so that when the welding seam copper set itself, the flame does not lead to burn out bags and can accommodate second to welding seam of the spill. When copper set of longitudinal seam welding, copper sets to figure 4 2 the location of the upper and lower two nozzle position in Max and Min respectively, so that the lead seal oil discharge and then on copper set of oil filled. Between the package for copper at both ends and lead sealing, under the sheath of nozzle on a lead tube, drew the leaking oil to oil pan, oil to avoid contact with the burner flame. For the same purpose, to the upper extension of nozzle, the high temperature and volatilization of oil and gas from contact with the burner flame. Lead sealing to complete, wait for after cooling, to charge by copper sets, to have the right amount of oil spills, immediately stop up the upper and lower nozzle with plug nut.
2, epoxy method with bare
the foregoing two methods of repair shall be under the condition of power cable, but in the actual operation should not be a power outage, this creates repair need epoxy glass cloth oil spill, but should do the following safety measures.
1) cable oil spill package should lead directly grounded.
(2) the abundant groundwater leakage personnel should take advantage of the insulation surface insulation.
(3) the operating field sand with fire prevention, fire extinguisher, etc.
its operating method are described below.
1) strip spill section of outer sheath, exposed the lead plane leaking fissure, dip in with cotton ball cable oil and benzene, lead to this layer is swabbed clean.
(2) make plugging reservoir. First according to the size of the lead layer of the leak, shearing oil resistant rubber ring, a lead into the oil spill layer surface; Again, overlapping winding and poly (ethylene with several layers of Syria, and the oil resistant rubber tightly tie up on the lead layer, outside the PVC belt tightly around the package again a layer of soft copper wire. Around the bag to wipe around the cladding surface impurities and cable oil.
(3) production of reinforcement layer. With a file wool first lead at the ends of the copper wire around the cladding layer surface, so that the bonding surface, wash oil, with benzene will lead layer is swabbed clean; Then with good epoxy resin coating, and in addition to wax, overlapping drying of glass ribbon winding and layers, using infrared light bulbs or thermal heating with epoxy layer, to accelerate the curing.
(4) after check no leakage, to repair the cable outer sheath, reinforcing layer.