Wire and cable in the process of operation often occurs a variety of unforeseen obstacle titles, the most direct reason is the loss of insulation and breakdown, cable damage.
Wire and cable
The following six are the main reasons for the obstruction of wires and cables:
First, environment and temperature.
The external environment and heat source where the cable is located can also cause the cable temperature to be too high, insulation breakdown, and even explosion and anger.
Second, the destruction of external forces.
According to incomplete statistics, the destruction of external forces can be described as the number one "killer" of wires and cables. Because the speed of urbanization in China is accelerating, almost everyone is doing large-scale transformation projects. In the process of construction, the cables are damaged horizontally in different cities. Some of them will block the cables completely, while others will leave "sequelae" to the cables, so that the protectiveness of the cables is too lost and the development of the cables will be prevented. Birth rate.
Thirdly, insulation is damped.
This kind of encounter is also very common, the same generally occurs in the discussion place of the cable buried directly or in the drain pipe. For example, discussing the fabrication of unqualified cables and commenting on the requirements of wet climate will make comments into water or vapor, which will form a branch of water for a long time under the effect of electric field, and gradually infringe upon the insulation strength of cables and prevent them from forming.
Fourth, cable discussion is hindered.
Cable discussion is the key to the thinnest cable line. Cable comments caused by staff's direct mistake (poor construction) often occur. In the discussion process of cable manufacturing, if there is discussion about the original network, such as not tightly pressed and inadequately heated, the insulation of cable head will be lost in the city, and then cause disorder.
Fifth, long-term overload operation.
When people are overloaded, things will fall down. Cables are no exception. Because of the thermal effect of the current, it is necessary to heat the conductor when the load current passes through the cable. At the same time, the skin effect of the charge, the eddy current consumption of the steel armor and the consumption of the insulating medium will also produce additional heat, and then the temperature of the cable will rise. When long-term overload operation, excessive temperature will accelerate the aging of insulation, so that insulation is broken down. Especially in the hot summer, the temperature rise of the cable often leads to the first breakdown of the thin insulation of the cable, so in summer, there are more obstacles to the cable.
Sixth, chemical decay.
Cables buried directly in areas with acid and alkali effects often form armor, lead or outer shield of wires and cables to be degraded. The protective layer suffers chemical or electrolytic degradation for a long time, which results in the failure of the protective layer and loss of insulation, and also leads to the deterioration of cables - the degradation environment of cables in units is equally serious.