Centerless grinding work allows unwanted material to be removed by abrasive techniques. This style of production is often used to create industrial tools and machine parts. The piece being worked on can either be fed into the grinding unit in which case the procedure is deemed through feed grinding, or in the case of larger pieces, the grinding devices can be attached to it, in which case the process is called plunge grinding. The process removes bits of material from the outer edge of a component, reducing it in size. It eliminates the need for centers, chucks, or other holding devices, and it permits the creation of high precision at considerable speed. This makes it ideal for mass production. There are three main parts to a grinding unit: a wheel for grinding, a wheel for positioning, and a work support blade.
The abrasives found in the grinding wheel of this process will be similar to the centered grinding method that makes use of spindles to hold forms in place. The wheel for positioning will generally be made of rubber compounds where the unit will rest. This wheel will turn at a fraction of the speed of the grinding wheel, say at 30 rpm versus 1300 rpm for the grinding wheel. The blades that cut will often be fashioned from carbide, which provides greater strength, or from ceramic and bronze. The blades are angled to aid in rounding.
Centerless grinding companies can now be found all over the world. While the fundamentals have remained the same, refinements of the designs for the machine have permitted greater speed in production as well as more exact tolerances. Cylindrical objects will usually be used in conjunction with the through feed form of this procedure. Objects with diameters that vary are more likely to use the plunge method. The calculations needed to determine the desired radius can require complex trigonometry calculations. To ease this portion of the process there are databases that exist to provide examples of this.