When the spiral cable is in use, the phenomenon of aging will occur. The common reasons for the aging of the spiral cable are: 

1. Obstruction of cable joints

The cable joint is the weaker link in the cable line, and the cable joint obstacle caused by the direct fault of the staff (poor construction) often occurs. In the process of manufacturing cable joints, if there are reasons such as insufficient joint crimping and insufficient heating, the insulation of the cable head will be reduced, and the conduction will be weakened, which will stimulate the event.  

2. Insulation is damp

This condition is also very common and usually occurs at cable joints in direct burial or in pipes. For example, the manufacture of cable joints is different and the joints are made under humid climate conditions, which will cause the joints to enter water or mix with water vapor. After a long time, water branches will be formed under the action of the electric field, which will gradually damage the insulation strength of the cable and form obstacles.

3. Long-term overload operation

When the load is running, due to the thermal effect of the current, the conductor will inevitably heat up when the load 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 generate additional heat, which will increase the temperature of the cable. During long-term load operation, excessive temperature will accelerate the aging of the insulation, and even the insulation will be broken down. More and more in the hot summer, the temperature rise of the cable usually causes the weak point of the cable insulation to be broken down, so in the summer, there are many obstacles to the cable.

4. External Injury 

Judging from the operation analysis in recent years, Haipudong is more and more in the rapid economic development, and now a considerable number of cable obstacles are formed due to mechanical damage. For example, non-standard construction during cable laying and installation can easily cause mechanical damage; civil construction on directly buried cables is also easy to damage the cables in operation. Occasionally, if the damage does not matter, it will take several months or even years for the damaged part to break down to form an obstacle. Occasionally, if the damage is important, a short-circuit obstacle may occur, which directly affects the safe production of electricity and electricity units.