Page 37 - EngineerIT November 2021

Figure 4: Flange type transducer calibration Figure 5: Square Drive type transducer calibration Figure 7: The 10 N∙m torque rig
Torque Transducers including Square Drive, Flange Type and Smooth Shaft Transducers. Figure 4 measurement standards and techniques.
and Figure 5 depict the calibration of a flange type and square drive type transducers respectively. The Torque Laboratory is driven by advances
The laboratory possesses a wide range of adapters that are needed to mount most of in technology and an ongoing increase in
the transducers that are typically found in industry (Figure 6). In the rare event that available industrial demand for torque measurement
adapters cannot be mounted to the client’s transducer, the client will be notified before accuracy and precision.
calibration commences. In such cases, an arrangement for the fabrication of the needed adapters NMISA is a type 3A entity and agency
will be discussed. To keep up with the ever-increasing pace of development, the laboratory is of the Department of Trade, Industry,
constantly developing and refining its torque measurement capabilities. This leads to a variety of and Competition (the dtic), established
research and development projects. and fulfilling its legal mandate under the
One of these research projects includes the development of torque measurement Measurement Units and Measurement
capabilities in the lower torque ranges (< 1000 N∙m). The laboratory is currently working Standards Act, Act no. 18 of 2006: to keep the
on developing two torque rigs, the 100 N∙m (Figure 7) rig and the 1000 N∙m (Figure 8) rig. National Measurement Standards for South
These will be used to perform calibration of torque transducers using the beam and weights Africa and ensure global equivalence of our
principle. Another project aims to use the kibble balance principle to realise continuous measurement units. n
torque measurements in accordance with the international redefinition of the kilogram. The
dissemination of torque angle traceability through the calibration of torque angle transducers For more information visit www.nmisa.org
(Figure 9) is also currently in development. Online Shop: https://store.nmisa.org/
The NMISA Torque Laboratory is accredited by the South African National Accreditation System Facebook: National Metrology Institute of
(SANAS) (accreditation number: 1621). The goal is to continually improve the Institute’s torque South Africa https://www.facebook.com/
NMISouthAfrica
Twitter: @NMISouthAfrica https://twitter.
com/NMISouthAfrica
Instagram link: https://instagram.com/
nmisouthafrica?utm_medium=copy_link
LinkedIn: National Metrology Institute of
South Africa (NMISA)
https://www.linkedin.com/company/
national-metrology-institute-of-south-africa/
YouTube: National Metrology Institute of
South Africa NMISA
https://www.youtube.com/channel/
Figure 6: Different types of adaptors available in the NMISA torque laboratory. UC0Koa9NKwm9B3zeVYOdsLig

Figure 8: The 1000 N∙m torque rig Figure 9: Torque angle calibration setup

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