There are three main type
of Centerless Grinding: Through-Feed, In-Feed and
Through-Feed: In through-feed grinding, the part rotates
between the grinding wheel and a regulating wheel as
For through-feed grinding, one or both
wheels of the centerless grinding machine are canted out
of the horizontal plane, as shown below. This imparts a
horizontal velocity component to the work piece, so that
outside feed mechanisms are not necessary.
grinding wheel is canted with respect to the other two
axes so that a component of its surface velocity pushes
the part in the direction shown below. This auto feeding
characteristic is useful for rapidly processing many
parts in quick sequence.
Because of the axial movement, through-feed parts can
only have right circular cylindrical ground surfaces.
The wheel cannot be dressed to grind more complex
Below are parts produced with the through-feed
centerless grinding process. As can be seen from the
quantities produced, through-feed grinding is primarily
a mass-production process because of its high
In-feed grinding differs from
through-feed grinding in that the part is not fed
axially so that the ground surface does not need to be a
right circular cylinder. The grinding wheel can be
dressed to accommodate the part. Once the work piece
part is in place, the grinding wheel is fed in radially.
Because of the set up time involved for each part,
in-feed grinding does not have the high throughput of
through-feed grinding. In-feed grinding is illustrated
In end-feed grinding, the part
moves in axially between the grinding wheels, stops for
grinding, and then moves out again. The wheel can be
dressed to form more complex shapes, but the part can
only get progressively smaller in diameter. End-feed
grinding is illustrated below.