The insulation of the cable tray is wrapped separately. Once it is not well protected and exposed to the ambient air for a long time, the insulation will be greatly reduced, and it will harden slowly until autumn. At this time, the insulation effect is not good. Generally, the cable insulation is made of rubber and plastic. What is the reason for its aging? Next, Shandong Cable Tray will explain it to you.
1. Long term overload operation: overload operation, due to the thermal effect of the current, when the load current passes through the cable, it will inevitably lead to conductor heating. At the same time, the skin effect of the charge, the eddy current loss of the steel armor, and the insulation medium loss will also produce additional heat, which will increase the cable temperature. During long-term overload operation, excessive temperature will accelerate the aging of insulation, and even the insulation will be broken down. Especially in the hot summer, the temperature rise of the cable often leads to the breakdown of the weak insulation of the cable first. Therefore, in summer, there are many cable failures.
2. Corrosion of chemical raw materials: cable bridge is directly buried in the area with acid and alkali effect, which often causes corrosion of cable armor, lead skin or outer protective layer. The protective layer is subject to chemical corrosion or electrolytic corrosion for a long time, resulting in failure of protective layer, insulation reduction, and cable failure.
3. Environment and temperature factors: The external environment and heat source around the cable tray and cable will also cause excessive temperature and insulation breakdown of the cable, which will seriously cause explosion and fire.
4. Cable joint failure: the bridge joint is a weak link in the cable route, and cable joint failures caused by direct negligence of personnel (poor construction) often occur. In the process of making cable joints, if there are loose crimping and insufficient heating of the original network, the insulation of the cable head will be reduced, which will lead to accidents.
In addition, the cable laying and installation are not standardized, which is easy to cause mechanical damage; Civil construction on directly buried cables is also easy to damage cables in operation. The above is the answer to the question. Do you have any questions to answer? Welcome to our website http://www.yeeones.com consulting service