The production process of key-locking thread inserts (also known as keenserts or keyserts) involves multiple steps to ensure precision threading, strength, and self-locking functionality. Below are the common manufacturing processes for key-locking thread inserts:
1. Material Selection and Preparation
Key-locking inserts are typically made from high-strength metal materials such as stainless steel, carbon steel, or copper alloys. The material choice affects the insert's corrosion resistance, wear resistance, and strength. Before production, raw materials undergo cleaning and pre-treatment to ensure the surface is free of impurities or contaminants.
2. Wire Forming
The production of key-locking inserts usually involves wire forming techniques. Metal wire is processed through cold or hot drawing to form a specific diameter and shape, ensuring uniformity and strength of the material.
3. Threading
Specialized threading equipment, such as thread rolling machines or lathes, is used to machine the internal and external threads of the formed wire. This step defines the shape, size, and precision of the threads on the insert. High precision is required to ensure a tight fit between the insert and the bolt or screw.
4. Key Installation
The unique design of key-locking inserts includes locking keys (or pins) that prevent bolts or screws from loosening. After threading, these keys are added to the insert. Automated systems precisely insert the keys into specific slots on the insert and ensure they are securely positioned.
5. Heat Treatment
To improve the hardness and wear resistance of key-locking inserts, heat treatment is applied. This involves processes such as quenching and tempering, where the material is heated and cooled to modify its internal structure, achieving the desired mechanical properties. The temperature and duration of the heat treatment are carefully controlled based on the material characteristics and application requirements.
6. Surface Treatment
Surface treatment is applied to improve the corrosion resistance, wear resistance, and appearance of the insert. Common surface treatment processes include:
Plating: Applying a metallic coating (such as zinc, nickel, or chrome) to the insert to enhance its corrosion resistance.
Oxidation: Creating an oxide layer on the surface through a chemical reaction to improve wear resistance.
Spraying or Coating: Applying a protective layer to the surface to prevent corrosion and mechanical wear.
7. Inspection and Quality Control
After production, key-locking inserts undergo strict quality inspections, including:
Thread Precision Testing: Verifying the size, angle, and accuracy of internal and external threads to ensure tight fits.
Key Fixation Testing: Ensuring the keys are firmly secured within the insert and will not loosen during use.
Surface Quality Testing: Checking for uniformity in surface treatments and identifying any defects or damages.
8. Packaging and Storage
Inserts that pass quality inspection are sorted and packaged, often in rust-proof and moisture-resistant packaging to ensure protection during transportation and storage.
Through these processes, key-locking thread inserts achieve strong thread connections, anti-loosening properties, and extended service life, making them widely used in industries such as aerospace, automotive, and mechanical manufacturing.