Inca Geometric rebuilds complex fixtures in tight timeframe

Each fixture, that had been in continuous three-shift production for over five years machining two crankshafts per cycle, weighed over two tonnes. Managing director Mike Cain says: "We had general arrangement, circuit and most key part drawings, however, due to in-use wear, modifications and service changes through the life of the units, we were involved in a considerable number of reverse engineering exercises. We also had to make full use of our machine tool build experience to ensure perfect alignment of the various datums enabling uninterrupted production to continue immediately following the shutdown." Prior to the shutdown Inca's engineers surveyed the fixtures on-site and produced as many items as possible to reduce the lead time for the rebuild. The company was totally responsible for stripping out the fixtures from the machine and shipping to the factory in Chartham, near Canterbury, and following the rebuild, return, refit, re-commission the machine and gain quality approval prior to factory start up. As part of the rebuild a complete strip down of each fixture was performed with all wear parts replaced. Location areas were either coated with ceramic or hard chromed and ground, all bearings, seals and linear ways were replaced. Each hydraulic cylinder was stripped and either refurbished or replaced, valves checked and all hoses replaced with new. Mr Cain concludes: "The critical part of the whole operation, apart from the tight schedule, was the resetting of clamping heights which was achieved by replacing and regrinding spacers and shims against a master component and then re-aligning each fixture."