Horizontal-spindle (peripheral) surface grinders
The flat edge of the wheel is in contact with the work piece, producing the flat surface. Peripheral grinding is used in high-precision work on simple flat surfaces; tapers or angled surfaces; slots; flat surfaces next to shoulders; recessed surfaces; and profiles.
The face of a wheel is used on the flat surface. Wheel-face grinding is often used for fast material removal, but some machines can accomplish high-precision work. The work piece is held on a reciprocating table, which can be varied according to the task, or a rotary-table machine, with continuous or indexed rotation. Indexing allows loading or unloading one station while grinding operations are being performed on another. An alternative term is snow grinding.
Disc grinders and double-disc grinders.
Disc grinding is similar to surface grinding, but with a larger contact area between disc and work piece. Disc grinders are available in both vertical and horizontal spindle types. Double disc grinders work both sides of a work piece simultaneously. Disc grinders are capable of achieving especially fine tolerances