During external cylindrical grinding, the workpiece is machined after being clamped on one side or between two centers. Depending on the grinding process, the grinding wheel can be guided radially using a plunging movement, angled to the workpiece or axially along the workpiece.
Peel grinding is used for cylindrical or tapered workpieces when the workpiece length to be machined is significantly greater than the grinding wheel width. Through a longitudinal movement, the grinding wheel, which is rotating with cutting speed vc, is moved parallel to the workpiece axle. At the reversal points, the delivery movement runs radial to the workpiece, with the grinding wheel not completely leaving the workpiece profile. To allow for greater accuracy in clamping, workpieces are usually mounted between centers. Multiple idle strokes (spark-out) are used to improve the shape accuracy and surface quality.
In general, there is always the possibility of removing the entire stock in one grinding pass. This procedure is referred to as external cylindrical circumference peel grinding. The feed motion is made outside the workpiece contact, and the longitudinal feed speed and the workpiece speed are lower than during traverse grinding. For more information on this procedure, see peel grinding.
During external cylindrical form grinding, the axial primary feed movement overlaps with an additional radial feed movement (NC-controlled) to create contours. In most cases, the entire stock removal is cut in one pass (peel grinding). Due to high stresses and strains, grinding wheels that are highly resistant to wear (diamond or CBN) are primarily used for this process. The use of narrow grinding wheels allows for various workpiece contours to be machined flexibly.
Angular plunge-cut grinding is used to process an external diameter and a face surface (shoulder). The diameter is finish ground first before the grinding wheel machines the face surface.
External cylindrical plunge-cut grinding is frequently used in areas of serial production for the machining of bearing seats, shoulders, grooves or nozzle needles. Metal removal is achieved through a radial feed of the grinding wheel onto the workpiece in the following order: roughing, finishing, fine finishing, spark-out. One variant of plunge grinding is external circumferential angular grinding (angular plunge-cut-grinding) where the grinding wheel axis is set around the B axis in order to machine high shoulders and circumferential surfaces. The infeed is carried out by a combination of axial and radial traverse motions. Profiled grinding wheels make it possible to create contours during plunge grinding.
Source: Conrad, Klaus-Jörg (eds.): Taschenbuch der Werkzeugmaschinen, 3. Auflage, München: Hanser Verlag, 2015. P. 645-647