The basic process flow of plastic cable production

Plastic wires and cables have a lot of contact in life, but many people should understand their production process. After all, we do not do this business is not necessary to understand. As a professional wire cable extrusion machine manufacturer, Taisheng is very familiar with the production process of wire and cable. The following is to share with you the production of plastic wire and cable Process flow.

1.Copper and aluminum single wire drawing

Wire and cable commonly used copper and aluminum rods. At room temperature, with a wire drawing machine through one or several wire drawing die holes, you can reduce the cross-section, increase the length and improve the strength. The first process of wire and cable enterprises is wire drawing. and the mold supporting technology is the main process parameter of it.

2.Monofilament annealing

When copper and aluminum monofilament are heated to a specific temperature, recrystallization improves the toughness of the monofilament. It reduces the monofilament's strength to meet the conductor core wire and cable requirements. The key to the annealing process is to eliminate the oxidation of the copper wire.

3.The conductor stranding

In order to improve the flexibility of wire and cable, a conductive wire core is easy to lay and install, using multiple single wires stranded. The conductor core stranding form can be divided into regular and irregular stranding. Irregular stranding is divided into bundle stranding, concentric composite stranding, special stranding, etc.

In order to reduce the area occupied by the conductor and the geometry of the cable, a compact form is used while stranding the conductor so that a usual circle can be turned into a semicircle, a fan, a tile, and a tight circle. Such conductors are mainly used for power cables.

4. Insulation extrusion

Extruded solid insulation is mainly used for plastic wire and cable. The main technical requirements of plastic insulation extrusion are as follows.

4.1. eccentricity: the deviation value of the extruded insulation thickness is an important symbol to reflect the level of the extrusion process. Most of the product structure dimensions and their deviation values are specified in the standard.

4.2. Smoothness: the surface of extruded insulation layer should be smooth without surface roughness, scorching, and impurities

4.3. Densification: The cross-section of the extruded insulation layer should be dense and solid, without pinholes visible to the naked eye, to eliminate the presence of air bubbles.

5. Cabling

For multi-core cables, it is generally necessary to twist them into a circle to ensure formability and reduce the shape of the cable. The stranding mechanism is similar to conductor stranding. Due to the large diameter of stranded knots, most of them are used without untwisting. The technical requirements for cable formation are to prevent the shaped insulation core from tipping over and causing the cable to twist; the other is to prevent the insulation layer from being scratched.

Most cable completion requires two other processes: filling to ensure the roundness and stability of the cable after completion; one is trying to ensure that the core does not loosen.

6. Inner sheathing

The insulation layer needs to be adequately protected to protect the insulated wire core from being damaged by the armor. The inner protection layer is divided into extrusion inner protection layer (isolation sleeve) and wrapping inner protection layer (cushion pad). Wrapping pad instead of taping should be carried out simultaneously with the cable formation process.

7. Armor

The inner steel belt armored structure can be used if the cable is laid underground and may be under certain positive pressure when working. When the cable is laid under positive pressure and tension simultaneously (such as in water, shaft, or soil with significant drop), the structure type with inner steel wire armor should be chosen.

8. Outer sheath

The outer sheath protects the wire and cable insulation layer from environmental factors of the structural components. The primary role of the outer sheath is to improve the mechanical strength of the wire and cable, chemical corrosion, moisture, water, and human immersion to prevent the cable from burning. Depending on the different requirements for the cable, the plastic sheath is directly extruded by the extruder.

If you have plans to produce wire and cable, join the wire and cable production industry, and want to buy high-quality and affordable wire cable extrusion machines or other related production equipment, welcome to contact us.