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The following BSI references relate to the work on this document:
Committee reference ISE/101/1
Draft for comment 17/30340200 DC

Foreword

Publishing information

This British Standard is published by BSI Standards Limited, under licence from The British Standards Institution, and came into effect on 31 August 2017. It was prepared by Panel ISE/101/1/2, Torque measuring and testing, under the authority of Subcommittee ISE/101/1, Uniaxial testing, and Technical Committee ISE/101, Test methods for metals. A list of organizations represented on these committees can be obtained on request to their secretary.

Supersession

This British Standard supersedes BS 7882:2008, which is withdrawn.

Information about this document

This revision introduces the relative measurement uncertainty interval, the range in which the expected error is likely to lie, calculated as the sum of the absolute relative deviation and the expanded uncertainty.

Some of the values in Table B.4 and Table B.7 are given to 8 decimal places, to allow users to check the data manually against these and the other tables in Annex B, and to eliminate rounding errors. It is not necessary to report at this level.

Presentational conventions

The provisions of this standard are presented in roman (i.e. upright) type. Its methods are expressed as a set of instructions, a description, or in sentences in which the principal auxiliary verb is “shall”.

Commentary, explanation and general informative material is presented in smaller italic type, and does not constitute a normative element.

Contractual and legal considerations

This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.

Compliance with a British Standard cannot confer immunity from legal obligations.

1 Scope

This British Standard specifies requirements for the calibration and classification of torque measuring devices, including those used for the calibration of torque tools.

It describes the method of calibration, calculation of calibration results and the classification of the torque measuring device in a static mode. The information to be given on the certificate of calibration is also listed.

Annex A provides diagrams of the application of torque, and examples for the calibration of torque measuring devices. Annex B indicates how to determine uncertainty of the calibration results of the torque measuring device.

2 Terms, definitions, abbreviations and symbols

3 Preparation for calibration

3.1 Reference standard

3.2 Condition and identification of a torque measuring device

3.3 Resolution of the indicator

3.4 Lower limit of calibration, T_min

3.5 Number of calibration orientations (see Annex A)

4 Preliminary procedure

4.1 Alignment

4.2 Temperature considerations

4.3 Instrumentation set-up

4.4 Preloading procedure

5 Calibration procedure

5.1 Selection of calibration torques

5.2 Application of calibration torques

6 Calculation of results

6.1 Determination of deflection, d

6.2 Determination of relative repeatability, R₁

6.3 Determination of relative reproducibility, R₂

6.4 Determination of relative errors of interpolation, E_it and E_itd

6.5 Determination of relative residual deflection, R₀

6.6 Determination of relative reversibility, R₃

6.7 Determination of relative errors of indication, E_i and E_id

6.8 Determination of uncertainty of measurement and relative measurement uncertainty interval

7 Classification of torque measuring devices

7.1 General

7.2 Determination of a classification and its range

8 Calibration certificate

Bibliography

BS 7882:2017

Method for calibration and classification of torque measuring devices

Current

Published:

31 Aug 2017