Centerless grinding is the process of removing material from the outside diameter of a work piece using an abrasive wheel.  In its simplest form, a centerless grinder consists of the machine base, grinding wheel, regulating wheel and work blade.  With centerless grinding, the work piece is not mechanically held to drive the part. 

The work piece is located on its outside diameter and supported by the work blade which is between the regulating wheel and the grinding wheel. The regulating wheel drives the part and the grinding wheel removes the material. 

centerless grinding process

There are two main types of centerless grinding: throughfeed grinding and infeed grinding.

Benefits of centerless grinding:

Tight tolerances

Excellent surface finish

Excellent roundness

Excellent straightness

Less stock compared to between-center grinding

Little work deflection (allows for grinding of long parts)

Ease of automation

Lower cycle times

Parts that can be processed by centerless grinding machines include axles, balls, bearings, bolts, bushings, camshafts, carbide rods, compressor shafts, copy rollers, cylinders, drills, gear shafts and hubs, injector needles, injector plungers and bodies, isolators, motor shafts, needles, pins, piston pins,  pivots, rotors, shafts, small crankshafts, spools, tubes, valve lifters, valve pistons and valve stems.

Centerless grinding is used in a number of industries such as automotive, aviation, aerospace, bearing, consumer products, glass, medical and tool and die.