These large machines have a reciprocating table that holds a workpiece and moves it against the wheel.
Surface grinding stainless steel.
The confusion is understandable considering those grinding with a large grit wheel remove a lot of metal quickly and in so doing leave a finish of very deep scratches.
Since stainless steel has a high intensity and strong adhesion force to avoid grinding wheel block the grinding wheel should be loose no 5 to no 8 in general.
They re used on cast iron steel brass and aluminum workpieces as well as some plastic workpieces.
Surface grinders have an abrasive grinding wheel that produces a smooth finish on flat surfaces.
When the requirement for surface roughness is low or it is mold grinding tight grinding wheel is appropriate.
When stainless steel grinding the workpiece surface deformation is severe and the stress and strain increase resulting in work hardening.