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9 janvier 2012 1 09 /01 /janvier /2012 22:00

Another article from the same source (Ricardo) as previous, this time related to the assembly process of the engine.

New Ricardo engine assembly facility 3One of the biggest challenges of the programme was not just to design and test a new engine ready for production in just 18 months, but to design the assembly process and the 600 square metre plant in which to produce it as well. Ground was broken in April 2010 and the plant was production ready, just four months later, in August 2010. “It is a model factory showing how things should be done,” says Ricardo assembly facility production manager Tom Soar.

An obvious question to ask is why the facility is sited in the UK and not in a low cost location: “We can achieve low cost just as well as anyone else,” explains Soar, and his views are echoed by no less a figure than Ron Dennis, executive chairman of the McLaren Group: “Several people have asked me why here, in England. I’m fiercely patriotic and we are desperately trying to communicate the importance of science and engineering for our country,” he says. “We came to Ricardo because we had a firm belief in its capability, its science, experience and commitment to excellence.”

The manufacturing building provides a semi clean-room environment with a positive air pressure system; it is modular, allowing for easy extension, and a BIPO cell (bed-in and pass-off engine dynamometer cell station) is integral. The production philosophy is one of lean manufacturing and the line is organised on a single piece flow (one engine per station), no faults forward basis; the line can take any engine in any order. It has been specified on the basis of producing 2000 M838T engines per shift per year. Stock control is operated on a ‘pull’ system (where stock control is based on production needs) and there is a 45-minute takt time – the cycle time before each unit moves to the next station. Two idle stations allow for an increase in production numbers at short notice.

13 assembly stations

The cylinder heads are assembled and set up on a discrete six-point line to one side of the hall, while the main line of 10 stations is positioned in the centre of the hall. There are also two sub-assembly stations, making a total of 13 in all. The highly sophisticated cylinder head production line not only builds the cylinder heads with valves, collets, springs, followers and stem seals but ‘pops’ the valves to ensure they are properly seated. It also performs a leak test on them, installs the camshafts and confirms all components are present.

All stations have a sophisticated human machine interface (HMI) which contains details of the work, indicates the tool to be used and keeps track of the status and cycle time. An HMI also controls parts bin selection, warning operators if they are about to select the wrong part. Rechargeable DC battery tools are pre-set and used for fastening, measuring rotations, angle and torque: all of these readings are stored in a database giving a full birth history of each engine. Once each operation is complete an operator acknowledges the fact with a step completion button. The job is only unlocked ready for the next station if all steps are completed.

Liquid gaskets are applied by machine and seal integrity is checked with an air pressure liquid leak detector and, if necessary, by using hydrogen gas and a sniffer.

Final stage: testing and power check

The final stage is for the engine to be bedded in, testing all the engine’s functions and also checking power and torque output. The sophisticated BIPO cell used for this stage incorporates hardware from three main UK suppliers and is operated using ST ARS software. The powerful dynamometer is rated at 460 kW and incorporates automated docking and undocking and coolant and oil fill. It also pre-heats the fluids and is equipped with a number of safety systems including an FM200 fire suppression system, smoke and flame detectors and explosion protection.

Once the BIPO session is complete, engines are ready for delivery to McLaren Production Centre in Woking, with a consignment leaving every working day.

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