1.Main process of wire and cable:
Wire and cable are made by drawing, twisting and wrapping. The more complex the model and specification, the higher the repeatability.
Under the action of external force,the metal is forced to pass through the die (roller),the cross-sectional area of the metal is compressed, and the required cross-sectional area shape and size are obtained.
In order to improve the softness and integrity of wires and cables, more than 2 single wires are interwoven in the specified direction, which is called stranding.
According to the different performance requirements of wires and cables, special equipment is used to coat different materials on the outside of the conductor.
2.The basic process flow of wire and cable manufacturing
Due to the different requirements of using characteristics, laying occasions and working conditions, the product structure is also in various forms.
(1)Copper, aluminum wire
Commonly used copper and aluminum rods for wires and cables, at room temperature, use a wire drawing machine to pass through one or several stretch die holes to reduce the cross-section, increase the length and increase the strength.
(2) Monofilament annealing
Copper and aluminum wires are heated to a certain temperature and recrystallized to improve toughness and reduce strength to meet the requirements of wires and cables for conductive cores.
(3) Stranding of conductors
In order to improve the softness of wires and cables and facilitate the laying and installation, the conductive core is made of multiple single wires.
(4) Insulation extrusion
Extruded solid insulation layer is mainly used for plastic wires and cables. The main technical requirements of plastic insulation extrusion are a. eccentricity b. smoothness c. density.
For the multi-core cable, in order to ensure the molding degree and reduce the shape of the cable, it is generally necessary to twist it into a circle.
(6) Shielding layer
Block the interference of external electromagnetic wave or prevent the interference of high frequency signal in the cable and mutual interference between line pairs .
(7) Outer sheath
The outer sheath is a structural part to protect the insulation layer of wires and cables from environmental factors. The main function of the outer sheath is to improve the mechanical strength, chemical corrosion resistance, moisture resistance, water immersion and prevent the cable from burning.