Basic introduction to wire and cable

Wire and cable: It is usually made of several wires or groups of wires [at least two in each group] twisted together, similar to rope. Each group of wires is insulated from each other, and is often twisted around a center, with a highly insulated covering layer on the whole. It is mainly used to transmit, distribute electric energy or transmit electric signals.
Wire and cable are mainly composed of the following four parts
1. Conductive core: made of high conductivity material (copper or aluminum). According to the requirements of the laying and use conditions on the flexibility of the cable, each wire core may be formed by twisting a single wire or multiple wires.
2. Insulation layer: the insulation material used for cables shall have high insulation resistance. The commonly used insulating materials in cables include oil-immersed paper, PVC, polyethylene, cross-linked polyethylene, rubber, etc.
3. Sealing sheath: protect the insulated core from mechanical, moisture, moisture, chemicals, light, etc. For insulation susceptible to moisture, lead or aluminum extruded sealing sheath is generally used.
4. Protective coating: used to protect the sealing sheath from mechanical damage. Generally, galvanized steel strip, steel wire or copper strip, copper wire, etc. are used as armor to wrap around the sheath (called armored cable). The armor layer also plays the role of electric field shielding and preventing external electromagnetic wave interference. In order to avoid the corrosion of steel strip and steel wire by surrounding media, they are generally coated with asphalt or wrapped with jute layer or extruded polyethylene and PVC sheath.