Power Required for Cutting

Power Required for Cutting

Power Required for Cutting -With the need to increase production with faster metal removal and multiple cuts, an engineer may put too much load on a machine too much for the available horsepower, bearings and gears.

The knowledge of power required in cutting helps the engineer to put only that much loads on the machine tool, which does not overload it. In metal cutting, horsepower is most often calculated in terms of unit horse power. Unit horse power is defined as the power required cutting a material at the rate of one cubic inch per minute.

Unit power (kW_u) which is similar to unit horse power, is defined in terms of kilowatts required to remove one cubic centimeter of material per second.

KW_u = kw / cm³ / s

Where F_t = tangential cutting force or simply the cutting force

f = feed rate in mm/rev.

t = depth of cut in mm.

F_t can be found as explained in article 30.12

An efficiency factor must be applied as no machine works at 100% efficiency. The basic equation is H.P. available for work = H.P. of motor on machine x efficiency. The efficiency indicates the power lost in overcoming frictional resistances in the main drive and feed mechanisms.