NPL’s Product Verification team worked with JJ Churchill’s engineers as part of the Sharing in Growth programme to further develop its measurement (metrology) capability.
JJ Churchill is a precision engineering firm employing 120 people and turning over £16 million a year. Working in exotic metals such as Jethete, Inconel 718, titanium and RR1000, the company machines compressor and turbine blades to extremely tight tolerances for the aero industry, along with cast aluminium and iron components for large diesel engines.
The first issue NPL helped the Nuneaton-based company address was a problem with a customer rejecting parts. This appeared to be as a result of a discrepancy between results from their Coordinate Measurement Machine (CMM) and their customer’s. As JJ Churchill’s Quality Manager, Paul Oldfield, said:
“All our CMM readings showed an exact match with the drawings the customer provided, but these were not replicated when the customer checked. Our CMM and the customer’s were telling two different stories.
“The problem was fundamentally with the two different sets of algorithms used by the two different CMM brands: measuring an aerofoil surface is not straightforward. When we showed this to the customer, we were able to explain the reason for the variations and to re-establish our quality credentials. We learnt a valuable lesson in the use of metrology.”
The discrepancy was identified by the team at NPL, who worked on JJ Churchill’s parts on their CMMs in Huddersfield. This work was supported by working with staff on CMM good practice and Measurement Systems Analysis practice following NPL’s standard Product Verification Health Check.
“This work has been valuable in understanding our CMM’s capabilities and our own ability to achieve the tight tolerances prescribed by our customer base,” explains Paul Oldfield, JJ Churchill’s Quality Manager. “We have reduced downtime by eight per cent, improved measurement stability and embedded best practice across our entire workforce. This, in turn, has eliminated the variation in working practices originally observed in a number of areas.”
NPL’s work will result in a reduction in downtime in the company, leading to increased production and cost reductions, and will help JJ Churchill to achieve their ambitious growth objectives.