A new testing procedure just published by the American Society of Mechanical Engineers (ASME) represents the final step in a decade-long effort led by the National Institute of Standards and Technology (NIST) to unite the United States with the rest of the world in evaluating the performance of coordinate measuring machines (CMMs).
CMMs, which make precision measurements of the dimensions of objects, are critical in such industries as aerospace, automobile and heavy equipment manufacturing to ensure that parts match blueprints, and for performing reverse engineering and managing process control. The United States has been the only major country with its own national standard for CMM performance evaluation because U.S. standards developers were concerned that the current version of international standard, ISO 10360-2, left major error sources unevaluated and contained ambiguities in the interpretation of the performance specifications. For a decade the U.S. team on the International Standards Organization CMM standard committee, led by NIST, worked to revise the international standard to correct these deficiencies and to develop a U.S. version that also added tutorials and optional tests to address concerns specific to the United States.
The new U.S. document has been published by the ASME as B89.4.10360.2, while its ISO counterpart is currently out for final approval by the international standards community. ASME B89.4.10360.2-2008 "Acceptance Test and Reverification Test for Coordinate Measuring Machines (CMMs) Part 2: CMMs Used for Measuring Linear Dimensions" may be obtained from ASME at http://catalog.asme.org/home.cfm?SEARCH=B89.4.10360.2.