Minimum Exponential Cost Allocation of Sure-Fit Tolerances

Abstract

The least cost allocation of sure-fit machine tolerances for Speckhart’s exponential cost model is solved in closed form, without numerical iteration, as a geometric program with zero degrees of difficulty. The results show the importance of an exponential cost sensitivity parameter defined as the “characteristic tolerance”. The theoretical minimum cost can be determined without specifying the corresponding tolerances. Specific minimum cost tolerances can be computed later in closed form if potential cost savings are significant.