江蘇春晨電纜有限公司生產(chǎn)春晨JBYH電機引接線YYYYY，

Power cable flammability, string ductility, once the fire,serious harm, especially in power plants and large substations,once the fire, spread to other circuits. Therefore, the power cablefire protection technology is one of the important technologies ofthe normal operation of the electrical system.

Power cable is an important part of electrical engineering, itsrole is used to transmit and distribute electrical energy. Powercable is composed of insulated core wire, insulation sheath andprotective layer. In order to adapt to a variety of complex layingenvironment, the power cable is designed to have good insulationperformance, waterproof performance and mechanical performance.However, when the current in the cable loop leads to overheating ofthe cable, the performance of the cable changes, and then a fireoccurs. In this paper, the fire protection technology of cable isdiscussed.

1. Create a good operating environment to avoid acceleratedaging and damage of cable insulation

Cable trench, cable tunnel should have good drainage facilities,such as setting shallow water groove, water collection well, andcan effectively drainage, if necessary, set up automatic stoppumping device, to prevent water supply, keep the internal drying.Longitudinal drainage slope of cable trench and tunnel. Preventwater, corrosive gas or liquid and flammable liquid or gas fromentering cable trench and cable tunnel. The cable tunnel should beventilated naturally, and the air temperature in the tunnel ishigher than 40~50 degrees when the normal load of the cable istaken, so the ventilation can be carried out by combining thenatural ventilation and mechanical exhaust. The fan of ventilationsystem should be linked with fire detector, so as to ensure thatthe tunnel can automatically stop the fire when the fire occurs,and the cable tunnel can not be used as the inlet duct of theventilation system.

It is necessary to avoid the cable fire door in normally closedstate, use the fire barrier to close the cable completely, and talkabout the sealing and sealing of the gap of the cable ditch coverplate, etc., which affect the ventilation and heat dissipation ofthe cable. And the cable is completely closed, also make the normalinspection of the cable becomes impossible, can not find cablefault in time.

According to statistics, the cable fire and explosion caused bythe cable head fault accounted for about 70% of the total cableaccident. The material and process of the empty cable headmust be strictly controlled. The service life of the cable headmust not be less than the service life of the cable. The ratedvoltage level and insulation level of the street shall not be lowerthan the rated voltage level of the connected cable and itsinsulation level. The withstand voltage between insulation pads onboth sides of insulation head shall not be less than 2 times of theinsulation level of cable protection layer. The joint form shouldbe adapted to the set of environmental conditions, and does notaffect the cable circulation capacity. Cable head on both sides ofthe range of 2 ~ 3M, should be taken as the fire spread fire bagprocessing.

Generally speaking, the weak link of cable perspective cableinsulation, so strengthening the monitoring and management of cablehead is an important part of cable fire protection. The middle headof the cable terminal cable head must not be placed in the cabletrench, cable tunnels, cable tray, cable interlayer must beinventoried, and used to detect a variety of testing e the cable head has abnormal temperature rise or odor andsmoke, the emergency exits early to avoid fire when the cable isput into operation.

There should be enough safe length distance between eachintermediate cable head, more than two cable heads are placed inthe same position, and close sealing measures should be takenbetween the cable head and other cables.

2. Strengthen the preventive test of the cable

After the cable and cable accessories are installed, the DCwithstand voltage test [preventive test] shall be carried out. Theexperimental data are compared and analyzed. It can be comparedwith the experimental data of the same cable, and also can becompared with the historical experimental data of the cable, so asto find the law of experimental data. If the DC withstand voltagetest is carried out, the leakage current value is one of thefollowing circumstances, the cable insulation may be defective,reflecting the defect location, and to deal with:

(1) with the increase of the test voltage or the increase of thepressure time, it rises faster

(2) compared with the same cable, the value increases more

(3) compared with the previous data measured by this cable,there is an obvious upward trend

(4) the unbalanced coefficient of leakage current betweenthree-phase is larger.

The above situation should be carefully analyzed, such asimproper test results caused by improper, you can appropriatelyincrease the experimental voltage or extend the test time,determine whether the cable meets the conditions of continuedoperation.

Power cable DC withstand voltage test standards see "electricale installation engineering electrical e transfertest standard" (GB50150-91) seventeenth chapters. The DC withstandvoltage test value of the commonly used plastic insulated powercables is 4 times, and the rated voltage of the cable is 15minutes.

3. Strengthen the management and operation monitoring of cablehead production .

4, prevent other e ignition ignitioncable春晨JBYH電機引接線YYYYY

Oil filled electrical e for ignition of ignition cableand coal handling, pulverizing system, gasoline engine system. Theymust take corresponding measures: the cable trench cover near theoil filled electrical e should be sealed, and when thetextile e fails, the oil will flow into the cable trench toignite the cable. The dust accumulated on the cable near the coalhandling and pulverizing system should be cleaned regularly toprevent the spontaneous ignition of the pulverized coal. The antiriot door of the pulverizing system should be packed with fireproofbox, so as to prevent the explosion door from action. [cnecPage]

5, use sealing, plugging, coating, package and other measures toprevent cable delay burning春晨JBYH電機引接線YYYYY

Fire retardant coating has a thin coating, does not affect thenormal heat dissipation, and can play a good insulation and flameretardant effect, but there are many defects. Including theselection of inappropriate fire retardant coating varieties, marketlate in the practical application of fake and shoddy products inthe use of poor results, spewing material is peeling, coatingthickness