The bearing and sealing diameters of shafts, axles, or gears, have the highest requirements for accuracy and surface finish. Based on the wear resistance such surfaces are often hardened and then finish machined. Similar requirements required for components such as cam lobes which are heat treated as forgings and are only hard machined.
In the past such surfaces were machined with ID or OD grinding on separate machines. Driven by cost effectiveness and flexibility, the classic grinding process with cutting fluid was substituted by hard turning, without limitations to accuracy and surface finish quality. In the Felsomat dry cutting process all features of the work piece are machined with hard turning with the exception of the ground surfaces specified on the drawing. These surfaces are machined with an integrated grinding spindle, removing a material stock of only 5 µm.
During the development of the Felsomat turning center FTC 180, consideration was given to achieving the highest possible rigidity of the machine, since the pre-machining has an extreme impact on roundness as well as on the surface finish. To achieve such superior quality was only possible be using mineral concrete for the machine base, a vertical work piece spindle integrated into the machine base and short levers of the axes system for the turret.
For in process control, Felsomat incorporates acoustic emission sensors for finish grinding. The dressing of the grinding pins is done automatically in the machine based on intervals that can be selected individually; thus tool change errors are eliminated.
A remarkable aspect of the Felsomat hard turn and grinding process is the environment friendly dry cutting. When required MQL can be added to the system.