TABLE OF CONTENTS Gregory A.Hetland, Ph.D.
Hutchinson Technology Inc.
Hutchinson, Minnesota
Dr. Hetland is the manager of corporate standards and measurement sciences at Hutchinson Technology Inc. With more than 25 years of industrial experience, he is actively involved with national, international, and industrial standards research and development efforts in the areas of global tolerancing of mechanical parts and supporting metrology. Dr. Hetland s research has focused on tolerancing optimization strategies and methods analysis in a sub-micrometer regime.
Measurement methods analysis is a highly critical step in the overall concurrent engineering process. Today s technology advancements are at a stage where measurement science is being pushed to the limit of technological capabilities. The past has allowed capabilities of measurement equipment to be acceptable if the Six Sigma capability was ?1 m (0.001 mm). Today, submicrometer capability is much more the norm for high technology manufacturing firms, with the percentage of features in this tolerancing regime getting larger and larger.
The primary objective of this chapter is to generate a capability matrix that reflects Six Sigma capability for all 14 geometric controls, as well as individual feature controls using an ultra-precision class coordinate measuring machine (CMM). In this particular case, a Brown & Sharpe/Leitz PMM 654 Enhanced Accuracy CMM was used for all testing to generate this matrix.
Analysis included variables that impact optimum measurement strategies in a submicrometer regime such as feature-based sampling strategies, calculations for determining capability of geometrically defined features, the thermal expansion of...
