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The world's largest facility for torque calibration

PTB can now calibrate torque transducers in the MN · m range. With the new 1.1 MN · m torque standard machine PTB has measurement facilities to span a range of nine orders of magnitude which can cover almost all of the requirements of industry and research with the necessary measurement uncertainty.

The new 1.1-MN · m-torque standard machine is currently still in testing yet already in demand by industry. A special torque transducer for a test stand of Siemens Power Generation has been calibrated. This torque transducer will be used for power measurements on heavy gas turbine prototypes for power plants.

Until now the only place in the world where traceable torque calibrations up to 200 kN · m could be carried out was at the French National Metrology Institute LNE in Paris. The new PTB facility can calibrate torque transducers up to 1.1 MN · m with a measurement uncertainty of 0.1 %. The installation space of this torque standard machine allows transducers for torque greater than 1.1 MN · m to be set up and calibrated in sub-ranges of their nominal range. Today, torque transducers up to 2.5 MN · m are produced.

In contrast to the scale presented by direct loading with masses used up to 20 kN · m the torque in this equipment is produced by means of a double lever arm of equal length with two mechanical spindle drives at its ends in the lower machine platform. The torque transducer to be calibrated is installed vertically in series with a reference torque transducer. The applied torque is measured by means of two tension-compression force transducer pairs which are arranged on a double lever arm on the upper cross-beam section. The design allows to measure the applied torque with almost no disturbing components. The new torque standard machine is under adjustment and testing since May 2004. Calibrations first up to 100 kN · m and successively up to 700 kN · m as well as tests up to 1.1 MN · m have provided proof of-principle and confirm the functional capability of the facility. First calibration orders for industry have already been carried out in this time. Regular calibration operation will start in 2005.

Contact at PTB:

Phone: +49-531-592-0