How does the wire or cable made?

2021-12-02
The procession of making wire and cable :
 Let me introduce your how to making the wire and cable as below,

1.Copper and aluminum monofilament drawing: copper and aluminum rods commonly used in wire and cable, at room temperature, use a wire drawing machine to pass through one or several die holes of a drawing die to reduce the cross-section, increase the length and improve the strength. Drawing is the first process of each wire and cable company, and the main process parameter of drawing is die matching technology.

2.Monofilament annealing: When copper and aluminum monofilaments are heated to a certain temperature, the toughness of the monofilament and the strength of the monofilament are reduced by recrystallization to meet the requirements of the wire and cable for the conductive core. The key to the annealing process is Prevent oxidation of copper wire.

3.Stranding of conductors: In order to improve the softness of wires and cables and facilitate laying and installation, the conductive cores are twisted with multiple monofilaments. From the twisting form of the conductive wire core, it can be divided into regular twisting and irregular twisting. Irregular stranding is divided into bundle stranding, concentric compound stranding, special stranding, etc.

4.In order to reduce the occupied area of ​​the wire and reduce the geometric size of the cable, the compacted form is adopted while the conductor is twisted, so that the ordinary circular shape is changed into a semicircle, a fan shape, a tile shape and a compacted circle. Such conductors are mainly used in power cables.
5.Insulation extrusion: Plastic wires and cables mainly use extruded solid insulation layers. The main technical requirements for plastic insulation extrusion:

a.Eccentricity: The deviation value of the extruded insulation thickness is an important symbol of the extrusion process level. Most of the product structure dimensions and their deviation values ​​are clearly specified in the standard.

 

b. Smoothness: The surface of the extruded insulating layer should be smooth, and there should be no poor quality problems such as rough surface, scorch and impurities.

 

c. Density: The cross-section of the extruded insulating layer should be dense and firm, and no pinholes visible to the naked eye are allowed to prevent the existence of air bubbles.

Cabling: For multi-core cables, in order to ensure the formability and reduce the shape of the cable, it is generally necessary to twist it into a circular shape. The mechanism of stranding is similar to that of conductor stranding. Due to the large pitch diameter of the stranding, most of them adopt the method without back-twisting.

 

The technical requirements for cabling: First, to prevent the twisting of the cable caused by the overturning of the special-shaped insulated core; the second is to prevent the insulating layer from being scratched. Most cables are cabling with the completion of two other processes: one is filling, to ensure the roundness and stability of the cable after cabling; the other is bundling, to ensure that the cable core is not loose.


Inner sheath: In order to protect the insulated wire core from being hurt by the armor, it is necessary to properly protect the insulating layer. The inner sheath is divided into: extruded inner sheath (isolation jacket) and wrapped inner sheath (cushion layer) . The wrapping cushion replaces the binding tape and is carried out simultaneously with the cabling process.

Armouring: It is laid in underground cables and may be subjected to a certain positive pressure during work. The inner steel tape armouring structure can be selected. When the cable is laid in the occasions with both positive pressure and tensile force (such as water, vertical shaft or soil with large drop), the structure type with inner steel wire armor should be selected.

Outer sheath: The outer sheath is the structural part that protects the insulation of the wire and cable from environmental factors. The main function of the outer sheath is to improve the mechanical strength, chemical corrosion resistance, moisture resistance, waterproof immersion, and prevention of cable burning of the wire and cable. According to the different requirements of the cable, the plastic sheath is directly extruded by the extruder.