The Role Of Wire And Cable Braiding

Wire and cable are mainly composed of three basic structural elements: conductive core, insulating layer and sheath layer.

There is no strict boundary between wire and cable, but in a broad sense, the cable structure is more complex, it has a complex sheath layer, while the wire structure is relatively simple, some only have conductors and insulating layers, and some only have braided wax coating Lightweight sheathing or wrapping with a lightweight soft sheathing.

The conductive core of wire and cable is used to transmit current.

In order to reduce power loss and voltage drop, the conductive core is generally made of copper and aluminum with high conductivity.

The function of the insulating layer is to prevent the current from leaking along the radial direction and to ensure the safety of use.

Therefore, the insulating layer is required to have good electrical insulating properties. Heat resistance and certain mechanical strength.

The protective covering outside the insulated core or the cabled core is called the covering of the cable (the protective covering outside the covering is called the outer covering).

The main function of the protective layer is to protect the insulating layer.

Its main properties are moisture-proof, oil-proof and anti-corrosion. Anti-sunlight aging, flame resistance, and mechanical protection (the role of the outer sheath is mainly to strengthen the mechanical protection of the cable. It withstands tension and bumps), and also has the functions of anti-electricity, anti-magnetic dry resistance, etc.

From the perspective of wire and cable sheathing, braiding is one of many types of sheathing or outer sheathing of wire and cable. However, according to the material used in the wire and cable braid and the different parts of the braid in the wire and cable structure, the role of the braid is obviously different.

1. The role of the fiber braid

For electrical wires, the fiber braid is a form of its lightweight protective layer. Its main function is to protect the insulation from various light, heat and moisture. The corrosion of low temperature, acid and alkali gas and the damage of external mechanical force ensure the safe operation of the wire. For cables, the fiber braid is often in the middle of the sheath to enhance the tear strength of the sheath. For example, the reinforced sheath is to add cotton yarn, hemp and other fiber braids in the middle of the rubber or plastic sheath to improve the protective layer strength.

Second, the role of metal braid

1. The metal braid mainly includes copper wire braid and steel wire (iron wire) braid. The main function of copper wire braiding is: l-shielding effect against electromagnetic interference, such as tinned copper wire braided blue cable,

Copper wire braided control cables, etc.

2. Eliminate the shielding effect of the surface potential of the power cable. It binds power lines and eliminates induced electricity, such as the overall shielding of high-voltage cables.

3. The shielding effect of security protection. Braided copper wire outside the main core insulation and has good contact with the ground core or used as a ground wire, which can respond to leakage in time, such as shielded mine cables, the main functions of steel wire braiding are:

l. Mechanical protection. Such as marine power cable CF31 type.

2. To withstand the longitudinal breaking force, such as the magnetic survey cable WC-GC, WCT type for marine geological exploration.

3. Magnetic field shielding.