Overview

Turning is a machining process for generating external surfaces by the action of a cutting tool on a rotating workpiece, usually in a lathe (Ref 3, p.135). Among various basic operations performed on turning equipment (boring, facing, cutoff, and threading), only straight turning is discussed in this chapter, because this operation is characterized by higher metal removal rate and, subsequently, by higher power consumption. The value of required machining power is the key element for maximizing productivity of cutting.

For almost three decades, the Machining Data Handbook (Ref 1 and Ref 2) has remained a reliable source of technical information on the cutting speed data versus depth of cut, feed rate, cutting tool material, and the workpiece materials.

The speeds and feeds for the various operations presented in Machining Data Handbook were obtained from the many sources and represent a tool life of 30 60 minutes applicable for carbide indexable inserts (Ref 1, p. XV). This handbook provides machining data when turning of steel with HSS, cemented carbide, cermet, and ceramic cutting tools. Unfortunately, machining data for turning of hardened tool steels with polycrystalline cubic boron nitride cutting tools were not included in this handbook.

Machining parameters for turning of steel with coated carbide, cermet, and ceramic cutting tools were adopted from this handbook and analyzed.

The machining recommendations (Ref 1, pp.1.3 1.33; 1.59 1.78) should be considered only as starting cutting parameters that require certain adjustments in accordance with today s metalcutting technology. It means that the final selection of cutting speeds...