How Are The Rings Of NSK One-Way Bearings Processed?

The raw material for manufacturing rings is cylindrical bar or tube. At present, according to different molding processes, NSK one-way bearing rings generally have the following manufacturing processes.
1) (Bar material) blanking – forging – annealing (or normalizing – turning (cold rolling forming) – heat treatment quenching, tempering – grinding – parts inspection – demagnetization, cleaning – submitting for assembly.
2) (Bar material, tube material) blanking – cold rolling forming – heat treatment quenching, tempering – grinding – parts inspection – demagnetization, cleaning – submitting for assembly.
3) (pipe material) blanking – turning forming – heat treatment quenching, tempering – grinding – parts inspection – demagnetization, cleaning – submitting for assembly
4) (bar stock) blanking – cold (warm) extrusion – turning – heat treatment quenching, tempering – grinding – parts inspection – demagnetization, cleaning – submit assembly

Ferrule forming method:
At present, in ferrule processing, there are mainly the following forming methods: forging forming, turning forming, cold rolling forming and cold (warm) extrusion forming. Among the above molding methods, forging molding is the most widely used, accounting for about 80% of the total production. For some small general-purpose products, rod (tube) materials can be directly turned into shape.

1) forging molding
Forging can eliminate internal defects of metal, improve metal structure, make metal streamline distribution reasonable, and metal tightness. The forging forming process is widely used in the forming process of NSK one-way bearings, which can complete the processing from small products with an inner diameter of ~20mm to extra-large products with an outer diameter of 5000mm. Common forging forming methods are: hot forging, cold forging, warm forging, hot forging is the main method in my country.
Due to the different forming processing equipment, hot forging process is divided into: free forging process, press forging process, flat forging machine forging process and high-speed cold forging machine forging process.
2) cold rolling
The cold rolling process is an advanced process method that can improve the utilization rate of materials, improve the compactness of the metal structure, and maintain the linearity of the metal. It is a chip-free processing method. Theoretically speaking, the products formed by cold rolling can be directly heat treated and ground without turning. At present, the cold rolling process is mainly used in medium and small deep groove ball NSK one-way bearings. The main process is:
Forging blank (ring) – turning (removing grooves) – rolling (grooving and chamfering) diameter – soft grinding of both ends.
When adopting the cold rolling process and forging forming process, the precision of the product is not only affected by the precision of the equipment, but also by the precision of the forming die.
3) Turning forming:
In the NSK one-way bearing industry, the traditional turning forming technology is to use a special lathe and adopt the centralized process method to complete the forming process. However, due to the difficulty in adjusting the equipment used in this method, the low precision of machine tools, and the low utilization rate of materials, this process method is being eliminated.
With the development of science and technology, CNC turning machine tools are developing rapidly and improving day by day. At present, some products with complex shapes and high precision requirements are increasingly using CNC turning forming technology.
To sum up, the direction of ferrule forming and processing should be towards the direction of high utilization rate of metal materials, high production efficiency and high forming precision. Therefore, high-speed upsetting technology, cold rolling technology, and CNC turning forming technology will be more and more applied.