pp 1–9 | Cite as

Proficiency Investigation of Torque Tools Calibration as a National Demand

  • K. M. KhaledEmail author
  • Seif M. Osman
Original Paper


The current paper represents a round loop for calibration of torque tools organized by NIS. These measurements are aimed to evaluate the performance of torque tools calibration laboratories in Egypt in the range from 200 N m up to 1000 N m in both clockwise and anticlockwise directions. Results are evaluated using En-value method and Z-score method based on the weighted means and the corresponding uncertainties. The outlier test and consistency test were performed on the measurements before applying the Z-score test. The Z-score evaluation shows that participants’ results are consistent specifically in the range from 400 N m up to 1000 N m. Further comparison with lower capacity artifact is recommended in the lower torque range.


Torque Calibration Proficiency test En-value Z-score 


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Copyright information

© Metrology Society of India 2019

Authors and Affiliations

  1. 1.National Institute of Standards (NIS)GizaEgypt

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