Custom Precision Parts - Wheel Needle

The CNC machining custom wheel needles are used in the coil winding process of transmission devices, which needs to have both wear resistance and impact resistance.

Customer Pain Points — Design Conflicts:
￮ Without Heat Treatment: The hardness of the needle body (the part in contact with the wire) is insufficient, leading to wear and a short lifespan.
￮ Overall Heat Treatment: The bushing area experiences increased hardness (e.g., >40 HRC), resulting in greater brittleness and a risk of chipping or breaking.

Solutions:
1. Modular Structure Design: Split the parts into two components – the needle body (wear-resistant core) and the bushing (impact-resistant support).
2. Heat Treatment of the Needle Body: Use heat treatment (quenching + tempering) to stabilize the hardness at 41-46 HRC, enhancing wear resistance.
3. Precision Machining of the Bushing: No heat treatment is done to avoid brittleness risks. Precision CNC machining ensures a smooth fit into the needle body.
4. Precision Assembly Process: Use cold pressing to insert the bushing into the needle body, ensuring overall structural stability.

Effects:
The wear resistance of the needle body is improved by over 200%, and the bushing has no brittleness or chipping.
The winding efficiency is increased by 77%.