scope:

Whirling is a fast method of producing worms: a tool holder ring, carrying a series of profiled carbide cutters, is set eccentric to the workpiece axis and rotates at a very high speed.

After a description of this machining process (axis movements and chip formation), the paper presents a case history: the introduction of a new whirling machine tool in a company that produces gear drives, especially worm gear speed reducers. There is a comprehensive view of all the benefits in terms of time and costs, compared to the previous situation with standard machine tools. The better quality obtained with the whirling process also reduced the cost of grinding after the heat treatment. All these benefits helped the company to maintain cost-effective production onsite, without relocating to foreign countries.

This paper also describes some geometric constraints in the worm shaft design, due to the whirling process, while there are no restrictions with the traditional machining.

There is also particular attention paid to the environment, because the thread whirling process needs no metalworking oils.