I. automotive wiring harness

Automotive wiring harness (car wire harness) realizes the physical connection  of the power supply and various electrical parts on the car. The wiring  harness is distributed all over the car. If the engine is compared to the  heart of a car, then the wiring harness is the neural network system of the  car, which is responsible for the information transmission between the  electrical parts of the whole car.

The system for manufacturing automotive wiring harness can be roughly divided  into two categories.

(1) divided by European and American countries, including China, TS16949  system is used to control the manufacturing process.

(2) Mainly Japan: Toyota and Honda, for example, have their own systems to  control the manufacturing process.

Automotive wiring harness manufacturers have their own particularity, and  attach importance to cable production experience and cable cost control.

Second, the introduction of commonly used materials in automotive wiring  harness.

1. Wire (low voltage wire, 60-600V)

Types of wires:

National standard lines: QVR, QFR, QVVR, QBV, qbv, etc.

Daily markings: AV, AVS, AVSS, AEX, AVX, CAVUS, EB, TW, SHE-G, etc.

German markings: FLRY-A, FLRY-B, etc.

American markings: SXL, etc.

Common specifications include wires with nominal cross-sectional areas of 0.5,  0.75, 1.0, 1.5, 2.0, 2.5, 4.0 and 6.0 square millimeters.

2. Sheath

Sheath (rubber shell), usually made of plastic, is inserted into it to ensure  the reliability of connection. The materials are mainly PA6, PA66, ABS, PBT,  PP, etc.

3. Terminal

A shaped hardware component, which is crimped on wires to connect different  wires to transmit signals, such as male terminals, female terminals, ring  terminals and round terminals.

The materials are mainly brass and bronze (the hardness of brass is slightly  lower than that of bronze), among which brass accounts for a large proportion.

2. Sheath fittings: waterproof plugs, blind plugs, sealing rings, locking  plates, buckles, etc.

Generally used to form connectors with sheath terminals.

3. Rubber parts of wiring harness through holes

It has the functions of wear resistance, waterproof and sealing. It is mainly  distributed at the interface between the engine and the cab, the interface  between the front cabin and the cab (two in all), the interface between the  four doors (or the back door) and the carriage, and the entrance of the fuel  tank.

4. Cable ties (clips)

An original, usually made of plastic, is used to fix the wiring harness in a  car. There are cable ties, bellows lock cable ties.

5. Tubing

Divided into corrugated pipe, PVC heat shrinkable pipe and glass fiber pipe.  Braided tube, wound tube, etc. Used to protect the wiring harness. (classified  by different diameters)

① Bellows

Bellows generally account for about 60%, or even more, in the binding of wire  bundles. The main feature is good wear resistance, high temperature  resistance, flame retardant and heat resistance in high temperature area. The  temperature resistance of bellows is between-40 and 150℃. Its materials are  generally divided into PP and PA. PA material is superior to PP material in  flame retardancy and wear resistance. However, PP material is stronger than PA  material in bending fatigue resistance.

② The function of PVC heat shrinkable tube PVC tube is similar to that of  corrugated tube. PVC pipes have good flexibility and bending deformation  resistance, and PVC pipes are generally closed, so PVC pipes are mainly used  at the branches of wire harness bends to make the wires smoothly transition.  The heat-resistant temperature of PVC pipes is not high, generally below 80℃.

6. Tape

Production tape: wound on the surface of wire harness. (divided into PVC,  sponge tape, cloth tape, paper tape, etc.) Quality identification tape: used  to identify the defects of the products.

The adhesive tape plays the roles of binding, wear resistance, insulation,  flame retardant, noise reduction, marking, etc., and generally accounts for  about 30% of the binding materials. There are three kinds of tapes for wire  harness: PVC tape, air flannel tape and duct tape tape. PVC tape has good wear  resistance and flame retardancy; The temperature resistance is about 80℃, the  noise reduction is not good, and the price is cheaper. Velvet tape and duct  tape are made of PET. Velvet tape has the best bandaging and noise reduction,  and its temperature resistance is about 105℃. Duct tape has the best wear  resistance, and the highest temperature resistance is about 150℃. The common  disadvantages of flannel tape and duct tape are poor flame retardancy and high  price.