The Key Processes of Automotive Wiring Harness Manufacturing: From Raw Materials to Finished Products

Automotive wire harness processing is a complex and sophisticated process involving multiple critical steps. This article will introduce these steps in detail, focusing on the most distinctive and critical aspects of wire harness processing.

The Basic Workflow of Harness Processing

Generally speaking, the processing of automotive wiring harnesses must adhere to the following procedural workflow:

  1. Material Incoming Inspection and Stock Release
  2. Stripping and Pre-assembly
  3. Crimping and Final Assembly
  4. Conductivity Testing
  5. Comprehensive Inspection and Packaging for Storage

Among these, the steps involving wire stripping, crimping, pre-assembly, and testing are the most distinctive and critical aspects of wiring harness processing.

Stripping Process

The stripping process is the foundation of harness processing and directly impacts the entire production timeline.

Key Points of the Stripping Process:

  • Precisely cutting wires and protective tubes
  • Bundling and organizing wires according to requirements
  • Establishing reasonable parameters for wire stripping lengths, sheath dimensions, etc.
  • Determining appropriate stripping techniques and bundling methods

Note:
If the stripped dimensions are too short, it may necessitate rework at every workstation, adversely affecting subsequent production.

Crimping Process

The crimping process is a crucial step in connecting wires and connector contact points, ensuring electrical conductivity and mechanical connection.

Crimping Quality Assessment Criteria:

  • Terminal crimp height
  • Surface condition
  • Pull-out force

Key Points of the Crimping Process:

  • Determining crimping parameters based on the terminal types prescribed in the blueprint
  • Creating a crimping operation manual
  • Highlighting specific requirements and conducting targeted training

Other Connection Techniques:

  • Ultrasonic metal welding
  • Riveting

These techniques have limited applications in automotive wiring harness processing but are significant in certain situations.

Pre-assembly Process

The pre-assembly process integrates semi-finished products from stripping or crimping with components such as protective tubing and rubber parts to form further semi-finished products.

Advantages of Pre-assembly:

  • Reducing the operational load on the main assembly line
  • Alleviating the workload at more challenging workstations
  • Rectifying bottlenecks and improving overall line efficiency

Note:
Pre-assembly operations must be performed per the prescribed pre-assembly process instructions, while process engineers should continuously adapt based on feedback from the production floor and summarize amendments.

Final Assembly Process

The final assembly phase combines various semi-finished products and materials on an assembly fixture to forge the completed wiring harness.

Key Factors in Final Assembly:

  • Clearly marked and comprehensive blueprints
  • Precisely aligned assembly fixtures
  • Thoughtful organization of workspace for material placement and identification
  • Clearly defined responsibilities and requirements at each workstation

These factors can significantly mitigate human error during assembly and contribute to enhanced overall assembly line efficiency.

Testing Process

Testing operations for wiring harnesses can generally be classified into two broad categories:

  1. Quality monitoring during the harness processing stages (including semi-finished product inspections)
  2. Electrical performance testing of the completed harnesses

Testing Contents Include:

  • Image inspection
  • Installation quality assessments
  • Functionality testing
  • Visual inspections
  • Dimensional checks

The automotive wiring harness industry commonly mandates 100% full inspection for these products.

Automation Trend

With the increasing prevalence of fully automated stripping and crimping machinery, many operations within the front-end stages (stripping, crimping, and pre-assembly) are progressively being consolidated into a single device for completion, indicating the industry’s trend towards automation.

Through these precise process workflows, automotive wiring harness processing enterprises can produce high-quality, reliable harness products, ensuring the safety and performance of automotive electrical systems.