Automatic tool selection for milling operations Part 1: Cutting data generation

Abstract

The selection of tools and cutting data is a central activity in process planning and is often liable to an element of subjectivity. It is further complicated by the wide range of choice presented by the various operation types and the huge portfolio of cutters and inserts available from many different tool manufacturers. This paper describes a procedure to select consistently and efficiently tools for rough and finish milling operations performed on a computer numerical controlled (CNC) machining centre. A wide range of milling operations is considered, including faces, square shoulders, slots, T-slots, pockets, holes and profiles. An initial set of feasible tools is generated that satisfy the constraints of the tool type, the operation geometry, the insert geometry and carbide grade, the workpiece material and the machine tool capacity. Each tool consists of a holder and one or more indexable carbide inserts. Aggressive cutting data are generated for each feasible tool using a rapid search procedure in the permissible depth/width/feed space for good chip control. The cutting data are further refined by a set of technological constraints, which include tool life, surface finish, machine power and available spindle speeds and feeds. The overall cutting data optimization criterion is selected by the user from minimum cost, maximum production rate or predefined tool life. A new optimization criterion, called ‘harshness’, allows the user to influence the chip thickness that is achieved for any given cutter. Any feasible tools that fail to satisfy all the constraints and optimization criteria are discarded.

Design of a Cutting Tools Information Integrated System

“…For example, there is no definition about uniform overall model, so which results in information redundancy. And data generally is stored in different places, so which makes it difficult to update information synchronously .And data model is inconsistent in different companies, so which makes it impossible to share information [4] Cutting tools is an important part in machinery manufacturing system. Cutting tools has a great influence on the surface geometry, dimensional precision, surface quality and processing cost [5,6].…”

Metaheuristic approaches to tool selection optimisation

“…Carpenter and Maropoulus provide a method for optimising tool selection on an array of different milling operation geometries [4,5]. The user is required to explicitly choose the geometry of the operation, and cannot go as far as a free form sculptured surface.…”

An integrated approach to the high-speed machining of moulds and dies involving both a knowledge-based system and a chatter detection and control system

“…Constraints considered were the dimensional tolerance of geometric features, workpiece surface roughness, workpiece material and machine tool characteristics. Carpenter and Maropoulos [19,20] developed the 'OPTIMUM' system for a range of rough and ®nish milling operations. Their research involved machinability data optimization under a range of technological constraints, which included tool life, workpiece surface roughness, machine power and available spindle speeds and feed rates.…”