Cutting Speed, Feed and Depth of Cut

Cutting Speed

Cutting speed is the rate at which material is removed from the surface of the work piece. It is specified from the surface of the work piece. It is specified in meters per minute (m/min). Choice of cutting speed depends on

·         Material of the work piece

·         Material of cutting tool

·         Type of operation

·         Rigidity of the machine and setup

·         Use of coolant etc.

Cutting speed is directly related to the tool life at higher cutting speeds tool life is less and at lower cutting speeds tool life is more.

Cutting speeds are fixed, taking into consideration an optimum tool life for each cutting tool material. These cutting speeds are listed in engineering tables.

Cutting speed is calculated from the formula
Where

V= Cutting speeds in meters per minute

D= Diameter of work piece in mm

N= number of revolutions of the work piece per min (RPM)

Feed

In turning, feed is longitudinal or cross travel of the tool in relation to the work piece. It is usually specified in mm/rev. The selection of feed rate depends on the following factors.

·         Power of the machine

·         Type of Operation

·         Rigidity of setup

Depth of Cut

It is the travel of the tool, Perpendicular to the axis of the work piece in longitudinal turning, and parallel to the axis in facing operation.