Cable structure composition, the structural components of wire and cable products, in general, can be divided into wire, insulation, shielding and protective layer of these four main structural components as well as filling elements and bearing elements. According to the use requirements and application occasions of the product, some products have a very simple structure, only a structural part of the wire, such as overhead bare wire, overhead contact line wire, copper and aluminum busbar (bus); The external electrical insulation of these products is ensured by the installation of insulators and space distance (that is, the use of air insulation).

Wire and cable products are the vast majority of the cross-section (cross section) shape is exactly the same (ignoring the error caused by manufacturing), the product is a long strip, which is due to the system or equipment is used as a line or coil and determined by the characteristics. Therefore, the study and analysis of the structural composition of cable products only need to observe and analyze from its cross section. The following is a detailed analysis of the cable structure and cable materials:

1, cable structure composition: wire

Wire is the most basic and essential component of the product to carry out current or electromagnetic wave information transmission function. Conductor is short for conductive wire core.

What are the materials of cable wire: The materials of wire are generally made of non-ferrous metals with excellent electrical conductivity such as copper and aluminum. In the past 30 years, the optical cable used in optical communication network has developed rapidly, and the optical guide fiber is used as the conductor.

2, cable structure: insulation layer

The insulation layer is a component that acts as electrical insulation around the periphery of the wire. That is, it can ensure that the transmitted current or electromagnetic wave, light wave only travels along the wire and does not flow outside, and the potential on the conductor (that is, the potential difference formed on the surrounding objects, that is, the voltage) can be isolated, that is, it is necessary to ensure the normal transmission function of the wire, and to ensure the safety of external objects and people. Wire and insulation layer are the two basic components that must be included in cable products (except bare wire).

What is the cable insulation material: In today's wire and cable, the cable insulation material classification is mainly plastic and rubber two categories of surface polymer materials dominate the material, derived from a wide variety of types of wire and cable products suitable for different uses and environmental requirements. Common wire and cable insulation materials are polyvinyl chloride (PVC) material, crosslinked polyethylene (XLPE), fluorine plastics, rubber material, ethylene propylene rubber material, silicone rubber insulation material.

3, cable structure composition: protective layer

When the wire and cable product is installed and run in a variety of different environments, it must have a component that protects the product as a whole, especially the insulation layer, which is the protective layer. Because the insulation material is required to have excellent electrical insulation properties, the purity of the material must be very high and the impurity content is very small; Often unable to take into account its ability to protect the outside world, so for the outside world (that is, installation, use occasions and use) a variety of mechanical forces to withstand or resistance, atmospheric environment, chemical or oil resistance, biological damage prevention, and reduce the risk of fire must be borne by a variety of protective structures. The main function of the cable sheath is waterproof, flame retardant and anti-corrosion. Many cable products dedicated to a good external environment (such as clean, dry, no mechanical external force indoor), or insulating layer material itself has a certain mechanical strength, weather resistant products, you can not have this component.

What kinds of cable sheath materials: cable sheath materials mainly include rubber, plastic, paint, silicone and various fiber products. The rubber and plastic protective layer is characterized by softness and lightness, and is widely used in mobile cables. However, because rubber and plastic materials have a certain degree of water permeability, it can only be applied when using polymer materials with high moisture resistance as cable insulation. Some users will ask why they see plastic as a protective layer on the market? Rubber sheath compared with plastic sheath characteristics: rubber sheath elasticity and flexibility will be higher, aging resistance, but the process is relatively complex. The plastic sheath has good mechanical properties, water resistance, rich resources, cheap price and convenient processing, so the market is more widely used. It should be noted that there is also a type of metal sheath, which has both mechanical protection and the shielding effect mentioned below, and also has corrosion resistance, compressive tensile strength and water resistance characteristics, which can prevent moisture and other harmful substances from entering the interior of the cable insulation, so it is widely used as the sheath of oil-soaked paper insulated power cables with poor moisture resistance.

4, cable structure: shielding layer

It is a component that isolates the electromagnetic field in the cable product from the external electromagnetic field; The cable product also needs to be isolated from each other between different wire pairs (or groups of wires) within it. It can be said that the shielding layer is an "electromagnetic isolation screen". Over the years, the industry is used to the shielding layer as part of the shielding structure, the reason is that in addition to the function of the shielding layer is electromagnetic isolation - that is, the information transmitted in the cable product does not leak, does not interfere with external instruments or other lines; Various electromagnetic waves from the outside world will not enter the cable product through electromagnetic coupling, and these functional requirements are different from the traditional protective layer function. It is also because the shielding layer is not only placed on the outside of the product, but also between the groups of each pair or multilog cable. In recent decades, with the rapid development of wire and cable used in information transmission systems, as well as the existence of more and more electromagnetic wave interference sources in the atmosphere, the variety of shielded structures has multiplied, and everyone's understanding of the shielding layer as a basic component in cable products has tended to agree.

Cable shield material: The cable shield layer uses metallized paper or semiconductor paper tape as the inner shield layer, and the outer shield layer is sometimes tied with copper tape or braided copper wire, and the braided layer material is generally red copper or tinned copper.

5, cable structure composition: filling structure

Many wire and cable products are multi-core, such as low-voltage power cables are mostly four-core, five-core cables (suitable for three-phase systems), the city telephone cable is 800 pairs, 1200 pairs, 2400 pairs to 3600 pairs. After these insulated wire cores or wire pairs are wired (or divided into multiple cables), the first is that the shape is not rounded, and the second is that there is a large gap between the insulated wire cores, so the filling structure must be added when the cable is formed. The filling structure is to make the cable outer diameter relatively rounded to facilitate the wrapping and squeezing of the sheath, and also to make the cable structure stable and internal stones. In use (during stretching, compression and bending during manufacturing and laying), the force is uniform without damaging the internal structure of the cable. Therefore, although the filling structure is an auxiliary structure, it is also necessary, and its material selection and shape design are also specified in detail.

Cable filling material: General cable stuffing includes polypropylene tape, non-woven PP rope, hemp rope, or recycled rubber processing of the general cheaper material. It can be used as a cable filling material, which must have no adverse effect on the insulation cable core, and the material itself does not have the characteristics of hygroscopic, easy to shrink, and non-corrosion.

6, cable structure composition: tensile element

Traditional wire and cable products use the armor layer of the protective layer to withstand the tension caused by external tension or self-weight. The typical structure is steel tape armor and steel wire armor (such as the submarine cable to use Phi 8mm thick steel wire, stranded synthetic armor layer). However, in order to protect the optical fiber from small tensile forces, so as not to affect the transmission performance of the optical fiber with slight deformation, a primary and secondary coating and a special tensile force element are set up in the optical fiber structure. In addition, such as the mobile phone headphone wire adopts the structure of thin copper wire or thin copper tape wrapped on the synthetic fiber wire to extrude the insulation layer, which is the tensile element. In short, in the special small, soft types developed in recent years, and require multiple bending and twisting products, tensile elements play a major role.

Cable tensile component materials include: steel strip, steel wire, stainless steel foil.

Qingdao Tianxing Cable Co., Ltd. focuses on the production of customized wire and cable manufacturers, main: fire wire and cable, power cable, control cable and other products, exported to more than 40 countries and regions around the world, the annual production capacity of 1 billion yuan. 6000 square meters of storage, standing hundreds of millions of inventory, order demand for rapid distribution and delivery, large prices more favorable. Hotline: 16678668098