How much do you know about the basic structure of Linyi power cables?
2023-04-03
Power cables are commonly used in urban underground power grids, internal power supply of industrial and mining enterprises, outgoing lines of power stations, and underwater transmission lines across rivers and seas. They are cable products used for transmitting and distributing high-power electricity in the main power system. The basic structure of Linyi power cable is composed of core wire (conductor), shielding layer, insulation layer, and protective layer. In power lines, the proportion of cables gradually increases. Linyi power cable is a cable product used in the transmission and distribution of high-power electricity in the power system trunk line, including various voltage levels of 1-500 kV and above and various insulated power cables.
The inner part of Linyi power cable is the wire core, and the outer part of the wire core is phase insulation and filler. Then, the outer part is three-phase integrated insulation, and the outer part of the integrated insulation is lead wrapped. The outer part of the lead wrapped is steel armor, PVC sheath, and other protective layers. The structure of Linyi power cables from inside out is: conductor, conductor shield, semi conductive tape, insulation shield, longitudinal waterproof layer, asphalt, lead sheath, PVC sheath, PVC tape, and semi conductive coating.
The allowable bending radius of Linyi power cable: The bending radius of Linyi power cable is related to its diameter, and the allowable bending radius is not less than a multiple of the cable diameter: 25 times for single core cables and 15 times for three core oil immersed insulated cables; 30 times the outer diameter of oil immersed paper insulated lead wrapped cables above 40mm, and 25 times the outer diameter of cables below 40mm; Rubber plastic insulated cables are 10 times larger.
Linyi power cable grade: According to domestic and international customs, cables are divided into low-voltage cables, medium voltage cables, high-voltage cables, and low-voltage cables with voltages of 35kV and below; Above 35kV -69kV is a medium voltage cable; 110-220kV is a high-voltage cable; Above 220kV is called an ultra-high voltage cable.
The function of the shielding layer and grounding wire of Linyi power cable: The shielding layer is divided into two parts: internal shielding and external shielding, both of which are to ensure good contact between the cable conductor and the insulation layer, and between the cable insulation layer and the inner sheath, eliminating the increase in surface electric field strength caused by the unsmooth surface of the conductor and inner sheath. The grounding wire is installed on the cable to mainly protect the induced voltage of the metal sheath. In the event of insulation breakdown failure or large fault current passing through the wire core, the insulation will break down, causing an arc and burning through the metal sheath.
The basic structure of Linyi power cable: The outer sheath of the cable is generally composed of three parts: inner lining, armor layer, and outer sheath. The function of the inner lining layer is to prevent the inner sheath from being corroded and damaged by the armor layer when the cable is bent, located between the armor layer and the inner sheath. The function of the armor layer is to reduce the impact of mechanical forces on the cable, so that the mechanical forces acting on the cable are borne by the armor layer outside the inner lining. The outer coating is placed outside the armor layer to prevent corrosion. Therefore, the function of the outer sheath of the cable is to protect the inner sheath from external influences and mechanical damage.
Quick Quote
* Note: Please be sure to fill in the information accurately and keep the communication open. We will get in touch with you as soon as possible
Shandong Zhongmai Cable Co., Ltd.
Tel:
Sales Phone:
E-mail:
WhatsApp:
Copyright © 2023 Shandong Zhongmai Cable Co., Ltd