Centerless Grinding Machines can be either computer numerically controlled (CNC), microprocessor controlled, or controlled conventionally via manually actuated hydraulic controls. These machines are designed to grind round workpieces without workpiece center holes or holding devices. The workpiece is held or balanced on a workrest blade device and either fed through two opposed wheels, one grinding wheel for stock removal and one regulating wheel for workpiece rotation and support, or plunged infeed and then ejected out of the grinding zone.

The thrufeed process is used to grind a workpiece outer diameter (OD) by passing it through the two wheels, driven by the regulating wheel, adjusted to a feed angle. This is often a high production operation utilizing automatic loading and unloading devices.

The infeed process is a plunge grind operation where a workpiece with a profile can be plunge or in-feed ground to finish dimensions and ejected to the unload zone. It is also quite common to utilize automatic loading and unloading devices with this type of centerless grinding machine.