PROFIT RATE MAXIMIZATION IN MULTIPASS TURNING WITH CONSTRAINTS - A GEOMETRIC-PROGRAMMING APPROACH

Geometric programming (GP) has been successfully used for the determin ation of cutting parameters considering minimum production cost or max imum production rate as objective functions. However, GP was found not to be useful for another important criterion of optimization, namely maximum profit rate, due to its signomial nature. In this paper it has been shown that, through modification of the constraint set, the prob lem of profit rate maximization can be converted to posynomial form, a nd thus can be solved by GP combined with linear programming (GP-LP). The problems of single and multipass turning are formulated and solved for profit rate maximization using the GP-LP approach. The resulting cutting conditions have been compared with the conditions obtained for minimum production cost and maximum production rate.