Application of parallel-two-ring-dimension-chain theory to computer aided calculating of machining- process- dimension -chain

This paper studies the characteristics of machining-process-dimension-chain (MDC) and parallel dimension chain, especially the special two-ring-dimension-chain in MDCs. It emphasizes that the two-ring-dimension-chain with parallel-connection relation is an important and decisive factor to find the deviation of machining process dimension in the MDC, and stresses its existence, necessity and position. Based on this, theory of MDC is proposed and presents a basic thought of calculating process dimensions and tolerances and deviations thereof in the machining process. Mathematical models for distribution of tolerance in calculating and analyzing operation dimension in the machining process are built. The distribution of dimension tolerance in the chains is optimized using optimizing algorithm. In view of the need of CAPP, a computer aided calculating (CAC) system is introduced into the MDC based on the theory of MDC in this paper.