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Thread Gauge Certification Agencies

The following independent agencies have informed API that they offer certification of thread gauges in accordance with API Specifications 5B, 7-2 and/or 11B.

API has not audited or certified these organizations, and does not endorse any of these agencies. This directory is being provided as an information source to address the gauging certification requirements of API Specifications 5B, 7-2 and/or 11B. API is not a party to any services provided by the individual agencies and provides no warranties, express or implied, as to the quality of their services.

Please contact the agencies directly to verify if the offered services meet your organization’s requirements.

NOTE: This informational listing has been reproduced from information contained in API Spec 5B, 15th Edition, Section 8.1.1; API Spec 11B, 27th Edition, Annex I, Section I.16.1; and API Spec 7-2, 1st Edition, Annex E, Section E.1.1 and Annex J.

API Spec 5B Thread Gauge Certification Agencies

  • Instituto Nacional de Tecnologia Industrial / Buenos Aires, Argentina
  • Stabilimento Militare Materiali Elettronici e di Precisione / Rome, Italy
  • National Institute of Metrology / Beijing, People’s Republic of China
  • National Institute of Standards and Technology / Gaithersburg, Maryland, USA
  • National Physical Laboratory / Teddington, Middlesex, England
  • National Research Laboratory of Metrology / Ibaraki, Japan
  • National Standards Laboratory / Chippendale, New South Wales, Australia

API Spec 11B Thread Gauge Certification Agencies

  • Instituto Nacional de Tecnologia Industrial / Buenos Aires, Argentina
  • National Institute of Metrology / Beijing, People’s Republic of China
  • National Institute of Standards and Technology / Gaithersburg, Maryland, USA
  • National Physical Laboratory / Teddington, Middlesex, England
  • Oil Country Tubular Goods Inspection Laboratory, China Natural Oil & Gas Exploration and Development Corporation / Baoji, Shaanxi, People’s Republic of China
  • Physikalisch-Technische Bundesanstalt / Braunschweig, Germany

API Spec 7-2 Thread Gauge Certification Agencies

  • National Institute of Standards and Technology / Gaithersburg, Maryland, USA
  • National Physical Laboratory / Teddington, Middlesex, England
  • National Research Laboratory of Metrology / Ibaraki, Japan
  • Instituto Nacional de Tecnologia Industrial / Buenos Aires, Argentina
  • National Institute of Metrology / Beijing, People’s Republic of China
  • API Grand and Regional Master Rotary Connection Gauges

If your organization has inquiries regarding this information, please contact certification@api.org