Plane-parallel functional surfaces on workpieces are generated most efficiently with the double disc surface grinding process. I.e. two parallel surfaces are machined simultaneously by two grinding wheels arranged in a set. Typical examples include roller bearing rings, piston rings, shims and seals, spacer plates, connecting rods, as well as blades and shearing plates.
The workpiece is transported and guided through the grinding gap by rotating perforated discs or, in rare cases,
by means of linear guides. The grinding wheels can rotate in the same direction or in opposite directions depending on the properties of the component. When the grinding wheels rotate in opposite directions, the transport wheel needs to exert less force and therefore wears slower; taller workpieces, however, create a tilting effect, which negatively influences the geometry of the parts.
Avoidance of thermal surface damage (grinding burn)
A particular challenge when using the double disc surface grinding process is the avoidance of thermal surface damage (grinding burn), as a sufficient amount of coolant cannot always be transported to the grinding zone through the very narrow grinding gap. Therefore, resin-bonded grinding wheels with grit sizes between 36 and 220 and extremely soft hardness grades between D and H are predominantly used.
Vitrified-bonded grinding wheels are preferred in some special cases, as these maintain their profile more efficiently and ensure a longer service life for heavy duty grinding tasks.