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STEP AP213 Coverage Analysis



Shaw C. Feng, Lihong Qiao


This report provides a quantitative coverage analysis of a draft Application Protocol (AP) for numerically controlled machining process plans in an international standard for product data representation and exchange. The analysis addresses the effectiveness of this AP by analyzing the coverage of the data model in the AP to the interface data from several commercial computer-aided process planning systems and numerical control programming systems. It is necessary to evaluate how much machining process information can be unambiguously exchanged among commercial systems in order to determine if the AP should proceed through the standards process as is or if there should be further changes. The report documents several measurement techniques, describes meassurement results, and reveals some limitations found in the AP.

NIST Interagency/Internal Report (NISTIR) - 6207
Report Number


application protocol, data exchange, NC programming, numerical control, process planning, product data, STEP


Feng, S. and Qiao, L. (1998), STEP AP213 Coverage Analysis, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 21, 2024)


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Created July 31, 1998, Updated October 12, 2021