4.1 Testing machines that apply and indicate torque are in general use in many industries. Practice E2624 has been written to provide a practice for the torque calibration and verification of these testing machines. A necessary element in Practice E2624 is the use of elastic torque measurement standards whose torque characteristics are known to be metrologically traceable to the International System of Units (SI). Practice E2428 describes how these elastic torque measurement standards are to be calibrated. The procedures are useful to users of testing machines, manufacturers and providers of elastic torque measurement standards, calibration laboratories that provide calibration services and documents of metrological traceability, service organizations using elastic torque measurement standards to calibrate and verify testing machines, and testing laboratories performing general structural test measurements.

1.1 The purpose of this practice is to specify the procedure for the calibration and verification of elastic torque measurement standards.

1.2 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.

1.3 This practice is intended for the calibration of static elastic torque measurement standards. The practice is not applicable for dynamic or high-speed torque calibrations or measurements, nor can the results of calibrations performed in accordance with this practice be assumed valid for dynamic or high-speed torque measurements.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.