A revolutionary new technology makes it possible to manufacture bevel gears faster and more simply than with conventional methods.

The uP-Gear technology focuses on small to medium-sized production runs.

Beveling

Bevel gears are used in everything from cars to industrial machinery. Until now, manufacturers have been able to choose between two different manufacturing methods: expensive and complicated solutions with special machines or solutions with end mills, which are flexible but limit productivity.

The uP-Gear technology developed by Voith Turbo, Sandvik Coromant and Heller is groundbreaking. Based on 5-axis milling machines, it combines flexibility with high productivity and low cost. The focus is on small to medium-sized production runs.

Opening Gear’s Tooth Gap

The solution comprises a set of milling tools that open the gear’s tooth gap step by step to the desired shape, in a soft state. After processing in the soft state, the gear is hardened, and a milling operation (with subsequent grinding)is carried out before it is fitted in the transmission.

The next stage of development is milling of extra-hard materials, where grinding has been the dominant technique. Kenneth Sundberg, who is responsible for the global commitment to gear milling at Sandvik Coromant, says the results of hard milling are so good that it might allow elimination of the grinding operation.

Indexing Carbide Inserts

This hob cutter with an indexable insert solution is a new concept for very large modules.

The company’s indexable insert solution for hob cutters is another completely new concept. The indexable carbide insert technology is well established for very large modules (from module 10, where the gears are 0.945 inches and upwards) used, for example, in the mining and wind power industries. Until now it has not been available for the smaller gears typical in transmissions used, for example, in heavy vehicles, agricultural machinery and trains (modules 5-8).

Together with Voith Turbo, Sandvik Coromant has developed a solution that is now available for line production. The biggest challenge was achieving the micrometer precision required to meet DIN standards (German Institute for Standardization).

The hob cutter, with 60 or so cutting teeth in spiral formation, increases productivity by 50 percent compared with established technologies.

Originally published in Metalworking World 3.2011, a business magazine published by Sandvik Coromant.