A Window approach for tolerance charting

This paper presents a simple and systematic approach to the tolerance charting process. A model representing the process links, as well as their associated signs, is constructed directly from the process plan in accordance to the operation sequence. The appropriate process links between any two feature planes are then captured off-line easily from the model. After establishing the links, constraint equations on working dimensions and tolerances are formulated. Having derived all the necessary relationships, the unknowns are solved using LINDO, a linear programming optimization software. The effectiveness of this method lies in its simplicity in constructing the model without the need to employ any comprehensive algorithms. Also, computations on unnecessary variables are avoided when employing this ‘Window’ method.