AN INTEGRATED PROCESS PLANNING APPROACH FOR CNC MACHINE-TOOLS

In view of the high investment and tooling cost of a CNC machining cen tre, the cutting and idle times should be optimised by considering the tool consumption and the non-machining lime cost components. In this paper, we propose a detailed mathematical model for the operation of a CNC machine tool which includes the system characterisation, the cutt ing conditions and tool life relationship, and related constraints. Th is new module will be a part of an overall computer-aided process plan ning system to improve the system effectiveness and to provide consist ent process plans. A hierarchical approach is presented for finding to ol-operation assignments, machining conditions, appropriate tool magaz ine organisation and an operations sequence which results in the minim um production cost.