High performance

Ever higher quality requirements with regard to operational reliability, durability, efficiency, quiet running and appearance require continual improvement of the manufacturing process. In this process superfinishing as the last manufacturing step has an important role to play as it defines the quality of the product. Superfinishing is characterised by the following parameters.

Highest surface quality and process stability

Today, the superfinishing process is used to generate the best possible surface characteristics which are exactly matched to the load of the functional surface area. In contrast to ground surfaces it is possible to achieve extremely stable characteristics in the process. This is true for a single workpiece and also true for workpieces in series production. Due to the high contact area there is practically no running-in to observe. The high material proportion results in an exceptionally low increase in clearance between the paired components for the whole of their life.

Improvement of the workpiece form

The contact zone with superfinishing machining is always configured to be large. This enables the considerable improvement of form errors such as lack of roundness, waviness and imprecise transverse forms.

Excellent economy

The integration of the superfinishing process in a production line can usually remove the need for the last fine grinding operation which incurs far higher machining costs. New technology furthermore also allows the superfinishing of fine or hard turned surfaces without a previous grinding operation (substitution).

Removal of the thermally induced surface zone

With grinding and hard and fine turning a microstructure modification at the edge zone occurs. This so-called soft layer is the result of the high temperatures in the contact zone between the workpiece and tool. Under this load the tool thus is subject to significant abrasion and rapid wear. In the process of superfinishing there is no significant thermal development. The edge zone is completely removed so that the undamaged, abrasion-proof base material becomes the load-bearing surface. As the base material is not thermally influenced, the risk of the formation of cracks or pitting due to changes in the microstructure is considerably reduced under a rolling load.

Improvement of bearing lubrication

The cross-hatch arrangement of the machining traces realised in superfinishing machining leads to a favourable distribution of the lubrication film. Furthermore, two-stage machining creates plateaus with a fine, load bearing surface and a cross-hatch pattern of grooves which serve as lubricant pockets.