The importance of proper geometric dimensioning and tolerancing as a means of expressing the designer's functional intent and controlling the inevitable geometric and dimensional variations of mechanical parts and assemblies, is becoming well recognized. The research efforts and innovations in the field of tolerancing design, the development of supporting tools, techniques and algorithms, and the significant advances in computing software and hardware all have contributed to its recognition as a viable area of serious scholarly contributions. The field of tolerancing design is successfully making the transition to maturity where deeper insights and sound theories are being developed to offer explanations, and reliable implementations are introduced to provide solutions. Machine designers realized very early that manufacturing processes do not produce the nominal dimensions of designed parts. The notion of associating a lower and an upper limit, referred to as tolerances, with each dimen sion was introduced. Tolerances were specified to ensure the proper function of mating features. Fits of mating features included clearances, location fits, and interference fits, with various sub-grades in each category assigned a tolerance value depending on the nominal size of the mating features. During the inspection process, a part is rejected if a dimension fell outside the specified range. As the accuracy requirements in assemblies became tighter, designers had to consider other critical dimensions and allocate tolerances to them in order to ensure the assembly's functionality.

The contents of this book originate from a collection of selected papers presented at the 9th CIRP International Seminar on CAT held in April, 2005 at Arizona State University, USA. The CIRP plans this seminar every two years, and the book is one in a series of Proceedings on CAT. It contains 33 papers by experts from around the world on subjects that range from theoretical models to practical applications.

This book contains selected contributions from the 6th CIRP International Seminar on Computer-Aided Tolerancing, which was held on 22-24 March, 1999, at the University of Twente, Enschede, The Netherlands. This volume presents the theory and application of consistent tolerancing. Until recently CADCAM systems did not even address the issue of tolerances and focused purely on nominal geometry. Therefore, CAD data was only of limited use for the downstream processes. The latest generation of CADCAM systems incorporates functionality for tolerance specification. However, the lack of consistency in existing tolerancing standards and everyday tolerancing practice still lead to ill-defined products, excessive manufacturing costs and unexpected failures. Research and improvement of education in tolerancing are hot items today. Global Consistency of Tolerances gives an excellent overview of the recent developments in the field of Computer-Aided Tolerancing, including such topics as tolerance specification; tolerance analysis; tolerance synthesis; tolerance representation; geometric product specification; functional product analysis; statistical tolerancing; education of tolerancing; computational metrology; tolerancing standards; and industrial applications and CAT systems. This book is well suited to users of new generation CADCAM systems who want to use the available tolerancing possibilities properly. It can also be used as a starting point for research activities.

This book focuses in particular on Geometrical Product Specification and Verification which is an integrated tolerancing view and metrology proposed for ISO/TC213. Common geometrical bases for a language allowing to describe both functional specification and inspection procedures are provided. An extended view of the uncertainty concept is also given. Geometric Product Specification and Verification: Functionality Integration is an excellent resource to anyone interested in computer aided tolerancing, as well as CAD/CAM/CAQ. It can also be used as a good starting point for advanced research activity and is a good reference for industrial issues. A global view of geometrical product specification, models for tolerance representation, tolerance analysis, tolerance synthesis, tolerance in manufacturing, tolerance management, tolerance inspection, tolerancing standards, industrial applications and CAT systems are also included.

Geometric tolerances are changing the way we design and manufacture industrial products. Geometric Tolerances covers their impact on the world of design and production, highlighting new perspectives, possibilities, current issues and future challenges. The topics covered are designed to be relevant to readers from a variety of backgrounds, ranging from product designers and manufacturers to quality inspection engineers and quality engineers involved in statistical process monitoring. Areas included are: • selection of appropriate geometric tolerances and how they stack up in assembled products; • inspection of parts subjected to geometric tolerancing from the macro to the micro and sub-micro scales; and • enhancement of efficiency and efficacy of quality monitoring. Geometric Tolerances provides the reader with the most recent scientific research in the field, as well as with a significant amount of real-life industrial case studies, delivering a multidisciplinary, synoptic view of one of the hottest and most strategic topics in industrial production.