Tradition maintained by full PLM

Bentley may be noted for producing what it calls 'hand-crafted' cars, but that should not imply that the company is anything less than technologically sophisticated. Indeed, it implements every possible aspect of CAD, PLM and CAM software in order to produce vehicles with maximum sales appeal and quality. CAD strategy manager John Unsworth says: "In previous projects, a lot of time and energy was wasted from changes at the end of the engineering process." He said that now, even though full PLM has now been applied to the Mulsanne model currently in pre-production: "The process is still not perfect, but it is better than it has ever been." Because Bentley cars are such premium products – the Mulsanne will have a recommended retail price of £220,000 – purchasers expect perfection. Says Unsworth: "We are very much a styling-driven organisation." Thus, the design process begins with use of sketches, clay models and use of Alias and ICEM Surf. Engineering design is undertaken in Catia V5, while the company makes extensive use of Delmia virtual assembly modelling with Enovia to manage the PLM, and 3DVIA composer is used to produce technical illustrations. A walk round the factory reveals automated assembly lines, robots putting 20 coats of lacquer on the veneered wood trim and leather which is examined and marked up by eagle-eyed inspectors, but which is then scanned and cut on large robotic flat beds. There is a lot of hand polishing and finishing and attention to detail, but computer controlled machines are used wherever they give benefits – CNC machines can, after all, work to precisions not possible for unaided humans. Bentley's owner Volkswagen has clearly invested significantly in the plant and its processes, so it was perhaps not surprising to hear Unsworth say: "We share our experiences with the other branches of Volkswagen, including Skoda and Seat, often on a daily basis… We have taken elements of the process further than other members of the group". Ian Swann, senior virtual assurance engineering manager, lists the advantages of the Delmia-based virtual build studies: "[It] reduces manufacturing assembly issues, improves build quality, supports the delivery of serviceability, contributes to faster products development and delivers enhanced training and visualisation." Putting a car together requires 831 operations to be undertaken at 30 assembly stations, while servicing issues investigated with the aid of Delmia included the discovery that changing a sensor in the bumper in the original version of the design would have required dropping the underfloor. One of the big advantages of running an integrated PLM system is said to be to assist collaboration between teams. The Mulsanne project took four years, but Unsworth says he expects other projects to be done more quickly. For instance, placing the dashboard assembly into the body frame could be investigated as soon as a scan was made of the first clay model, meaning any problems with assembly could be ironed out by the stylists before undertaking detailed engineering design. The next major step, according to Unsworth, will be to: "Take the PLM wider than the factory gates and integrate suppliers into the design and review process."