Gear Manufacturing – Precision Tooth Profiles from Blank to Finished Surface 

Gear manufacturing is divided into soft machining and hard machining, each requiring different processes. Soft machining includes gear hobbing, power skiving, and gear shaping, which cut the tooth profile into the component before hardening. After heat treatment, hard finishing is performed via gear generating grinding or profile grinding to correct distortion errors and create precision surfaces. Deburring and chamfering complete the process chain as indispensable intermediate steps. 

Gears require tight tolerances on tooth form, flank lines, and surface finish – even minimal waviness at the micrometer level can cause noise in the drive. Interfering contours, small run-outs, and internal gear teeth add further challenges, limiting the use of certain processes. Dimensional deviations from heat treatment must be  deliberately compensated in hard machining. For electric drives, the demands on smooth running and surface finish continue to increase. 

For internal gear cutting, EMAG primarily offers the processes of power skiving and gear shaping. Power skiving is the more productive choice: It operates continuously with axial feed and is two to three times faster than gear shaping. For workpieces with interfering contours or very small clearance, gear shaping offers design advantages, as the tool operates with precision even in confined spaces. 

A complete process chain begins with pre-turning of the blank, followed by rough gear cutting by gear hobbing or power skiving. Burrs are removed next, by roll deburring or deburring discs. After hardening, gear generating grinding or profile grinding handles finishing. The result: dimensionally accurate tooth profiles with a defined surface finish and long service life. 

Gear manufacturing is a core process wherever torque is transmitted – especially in automotive and its supplier base, commercial vehicle manufacturing, and agricultural machinery. Gear manufacturing is also becoming increasingly important for electric drives: High torques and motor speeds require particularly low-noise surfaces and tight tolerances. For this, EMAG provides specially tailored solutions – planetary gearboxes or bevel gears in electric vehicles, for example. 

Key factors include short cycle times, minimal non-productive time, and few setup changes. Power skiving in a single setup with pre-turning reduces part handling and concentricity errors simultaneously. In gear generating grinding, a second workpiece spindle lets loading and unloading happen within the cycle time. Deburring directly on the gear hobbing machine saves a process step. Gear shaving costs less than grinding and still achieves low-noise results – a clear advantage for high-volume production.