Understand The Key Points of Manufacturing Process And Quality Control of Automotive Wiring Harnesses

As an indispensable means of transportation in modern society, the internal electrical system of automobiles is becoming more and more complex, relying on a large number of precision wires and connectors to achieve functional control and power transmission of the whole vehicle. As a "neural network" connecting various electrical components of the vehicle, the manufacturing process and quality control of the wiring harness directly affect the performance, safety and stability of the whole vehicle. This article will take you to an in-depth understanding of the manufacturing process and key quality control points of auto wires, and introduce the performance comparison of several commonly used wires for automotive use on the market, to help you better understand the technical background of this key component.

Basic concepts of automotive wires and wiring harnesses

Automotive electrical wires usually refer to low-voltage, high-temperature resistant, oil-resistant and corrosion-resistant wires used inside the car. These wires will eventually be processed into a complete wiring harness system, which runs through the engine compartment, dashboard, door, chassis, roof and other parts of the vehicle to achieve power distribution, signal transmission, function control and other functions.

Compared with ordinary industrial wires, vehicle wires have higher technical requirements:

• Must work stably for a long time in complex environments such as high temperature, vibration, and humidity;

• Need to have excellent wear resistance and oil resistance;

• Require compact size to facilitate wiring in limited space;

• Have good flame retardancy and insulation performance.

Manufacturing process of automotive wiring harnesses

1. Material preparation

First, professional automotive wire suppliers provide wire raw materials that meet automotive standards, including conductors (generally multi-strand copper wires) and insulation layers (such as PVC, XLPE, silicone, etc.). These automotive wire materials need to undergo raw material certification, environmental testing, and temperature resistance evaluation.

2. Stripping and wire cutting

Use automated wire stripping equipment to accurately cut the length according to the design drawings, and strip the insulation layer at both ends of the wire, leaving the conductor for crimping.

3. Crimping terminals

Firmly connecting the wire and the terminal through a crimping machine is a key link to ensure signal integrity and mechanical stability. The crimping quality must pass the tensile test.

4. Plug and Assemble

Insert the crimped wires into the corresponding connectors according to the circuit diagram and combine them into branch harnesses. Then use tape, corrugated tubes, cable ties, etc. to wrap and protect.

5. Inspection and Testing

Through electrical performance testing, appearance inspection, high temperature aging testing and other means, each harness is fully inspected to ensure that its conductivity, insulation and mechanical strength meet the standards.

Comparison of 3F automotive wire product performance

The three representative products of 3F automotive wiring harnesses are shown in the following table:

As can be seen from the table, the performance of wire for automotive use varies significantly:

EV XLPE automotive wire has high temperature and high pressure characteristics, and is the preferred choice for high-demand scenarios such as new energy vehicles;

QB-B PVC wire is suitable for medium temperature and low pressure applications, and has a high cost-effectiveness;

QFR PVC wire is mainly used in parts with low power requirements, such as interior decorative lights, electric window control circuits, etc.

Key points of quality control for automotive wiring harnesses

1. Material selection compliance

The purchased auto wire must comply with ISO 6722, JASO D611, QC/T 730 and other standards to ensure that the conductor is of high purity and the insulation layer meets the temperature resistance level and environmental protection requirements.

2. Crimping reliability control

Whether the crimping is firm directly affects the stability of the vehicle circuit. The crimping quality can be effectively monitored through tensile testing and metallographic section analysis.

3. High temperature resistance and aging test

The whole harness is subjected to environmental simulation tests such as high temperature, humidity, and salt spray to test its reliability under extreme conditions.

4. Electrical performance testing

Including continuity test, resistance test, insulation test and short circuit test to ensure that the wiring harness can work normally without leakage risk.

5. Consistency and batch control

Establish a production traceability system to achieve traceability of each batch of materials, products and process parameters.

Conclusion

Today, as the degree of automotive electronics and intelligence continues to increase, the importance of automotive wiring harness manufacturing quality is becoming increasingly prominent. Choosing high-quality automotive electrical wire and reliable automotive wire suppliers, combined with scientific manufacturing processes and rigorous quality control systems, is the cornerstone to ensure the stable operation of automotive products.

Whether it is traditional fuel vehicles or new energy vehicles, the performance requirements for vehicle wire are continuously upgraded. In the future, with the in-depth development of lightweight, high-voltage and modular trends, automotive wiring harnesses will also move to a higher level in material innovation, structural optimization and intelligent manufacturing.