![<?echo $_SERVER['SERVER_NAME'];?>](/template/twentyseventeen/skin/images/header.jpg)
The process is to pass a linear molecular structure of polyethylene (PE) material through a specific processing method to form a cross-linked polyethylene of a bulk net-like structure. The long-term allowable operating temperature is increased from 70°C to 90°C (or higher), and the short-circuit allowable temperature is increased from 140°C to 250°C (or higher), greatly improving the premise of maintaining its excellent electrical performance. Actual use performance.
Identifying spurious breakdowns of cross-linked cables:
In the process of using the series resonance test system to perform partial discharge and high voltage test on medium-voltage cable finished products, false breakdown phenomenon may suddenly occur in the test process for various reasons. How to correctly identify whether the cable itself has a true breakdown or Other causes of false breakdown of the cable are significant for improving the efficiency of the cable factory test.
The partial discharge and high voltage test of medium-voltage cross-linked power cables are carried out in a shielded room on a disk-by-disc basis. In this case, re-examination of the insulated cores may be considered. If the core test is passed after the cores are replaced, the voltage test should be able to determine the cable. Breakdown really happened. Alternatively, if the breakdown voltage is gradually reduced, it can be determined that a true breakdown of the cable has occurred. If the breakdown voltage of the cable is the same value, consider whether the end of the cable has occurred. Breakdown, at this time, the partial discharge switch of the partial discharge shield room door can be artificially closed, the shield room door can be opened, the pressure can be increased, the breakdown phenomenon can be observed, and the end breakdown position can be determined very quickly. If there is no breakdown at the end of the cable after the investigation, replace the multiple insulated cores and cables, and even retest the cable that has passed qualified or no-load retest. The breakdown voltage always maintains the same value, and the cable should be confirmed. There was a false breakdown and the equipment should be inspected and tested before troubleshooting. However, for some large-length single-core medium-voltage cross-linked cables for cross-checking, it is also necessary to check whether they have exceeded the allowable load of the test equipment. In this case, the detuning tripping phenomenon will occur during the test, do not arbitrarily determine the cable Breakdown.
There also need a special case described here, the internal cable insulation may short circuit, the series resonant test system may not resonant step, which is a special cable breakdown. When this happens, it can be confirmed by simply replacing the insulated core with a good insulation test.
Flap discs are made by Aluminum oxide,calcined aluminum, SIC or zirconia coated cloth, also call as power flex discs. Flap discs have the advantages of grinding discs and fiber discs, making it easier for grinding and polishing disposable, reducing the work process and lower the grinding cost.
Abrasive grains include: Aluminum oxide, calcined aluminum, silicon carbide and zirconia.
Flap discs are widely used in grinding and polishing of wood, glass, stainless steel, futniture, mold, metal casting, weld seams and so on. Especially, zirconia power-flex discs fit in sanding seld seam of stainless steel. Flap discs have the features of quick speed, high efficiency, synchronous consumption, strong grinding force, fast heat disspation and good performance.
Flap Disc,Flap Disk,Diamond Flap Disc,Flap Disc For Wood
Henan Yuteng Abrasives Co.,Ltd , https://www.henanyutengabrasives.com