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NPL is home to the UK's national force standards – a set of seven machines used to generate precisely‑known forces in the range from 25 N to 30 MN. The most accurate of these are our four deadweight machines which use the Earth's gravitational pull on calibrated masses to realise forces with an uncertainty of 0.001 %. The largest of these can generate forces of up to 1.2 MN. Above this range, we generate forces hydraulically in machines with capacities of 5 MN, 12 MN and 30 MN. The machines are used to calibrate force-measuring devices which are then used in industry to make accurate and traceable force measurements.
The 1.2 MN machine was designed and manufactured in the 1980s. A major programme to replace its control system, both software and hardware, is under way. The opportunity is also being taken to improve certain aspects of its operation, including:
The 5 MN and 12 MN machines were constructed in the 1960s and 1970s respectively. Their current performance (a generated force uncertainty of 0.05 %) is at the upper limit of what UK industry requires.
We are continuously improving and reviewing our facilities and services within this force range by developing a new hydraulic machine resulting in the following improvements:
Find out more about NPL's Technical consultancy service
Find out more about NPL's Manufacture and supply of transducers service
Our research and measurement solutions support innovation and product development. We work with companies to deliver business advantage and commercial success. Contact our Customer Services team on +44 20 8943 7070