Tolerancing for Function

Summary Although the basic objective of design is to create mechanical systems which are first of all suitable for function, the way to achieve this aim is usually an indirect one. The designer has to observe a certain number of standards and technical rules relating to mechanical tolerances, geometrical and dimensional, which will enable to produce a design which is not only consistent with the function of the part, but also with manufacturing constraints, assembly limitations and inspection possibilities. These latter conditions determine essentially the economy of the industrial production of components. It is therefore a central concern of the design and manufacturing functions in industry to strive for a tolerancing system which would support the designer in finding an optimal way from functional requirements and production constraints to a comprehensive tolerance assessment of mechanical features composing the parts. This review is therefore concerned with identifying the remaining problems in tolerancing, their relations with functions and to suggest approach directions for their future practical solutions.