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The Gear Measurement was the 1st Special Interest Group (SIG) the BGA set up. The project that had the most support was to quantify the measurement uncertainty of UK gear measuring machines. It is still going.

As we know, gears are complex shaped precision components where deviations of 2 to 10μm are commonly specified to maximise power density, reduce cost, improve efficiency and minimise noise. This requires very high standard of measurement on the shop floor. The statistical measurement uncertainty of these machines is typically 1.8 to 3.0 μm and thus the risk from false acceptance and rejection of product is high. This risk can be minimised if you know how well your measurement process is performing.

The BGA round robin allows companies to bench mark their measurement capability against the rest of the gear industry. So far it has reached 14 SMEs so far on about 23 measuring machines. Each company takes 3 to 6 months to do the work and is provided with a confidential report containing an analysis of measurement uncertainty by NGML, the UKs national laboratory.

It also allows you to compare the performance of different measuring machines and different operators. Accurate gear measurement requires you to follow best practice, not only buying the best equipment

The confidential analysis results will show the measuring system is fit for purpose for your product gears. In the last 12 months a new smaller gear has been provided by Renown Gears who will retain the gear and a UKAS accredited calibration certificate with references data supplied by NGML.

If you are interested in learning more about this SIG and the round robin then please contact the BGA and you would be very welcome to join in. Membership of the SIG is free to BGA members.

Please contact Kirsty at the BGA if you wish to participate. We look forward to hearing from you.

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