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12 March 2012

MacDonald Humfrey Automation (MHA) and sister company Exmac Automation have

joined forces to help automotive engineering specialist Ricardo create a

state-of-the-art 600 square metre assembly facility to build its first ever

high-performance engine at Ricardo's Technical Centre in West Sussex. Providing

a near cleanroom production environment the facility has the capacity to produce

4000 engines annually across two daily shifts. Its core is a ten-station

vertical conveyor mini-line supported by incoming materials inspection and

line-side delivery of components. Each station is equipped with a sophisticated

MacDonald Humfrey 'Human Machine Interface' (HMI) providing guidance to each

operator on the precise sequence of operations required at each stage of

assembly' to ensure No Fault Forward' (NFF) assembly. Tools at each station are

instrumented to provide data directly into a central warranty database for each

engine, providing complete finished product traceability.

Each line station is interlocked via its HMI to ensure that all operations and

checks have been successfully completed and recorded before the line can be

indexed and the engine moved forward to the next station.

Says Ricardo's Dave Thompson: "Exmac understood our brief, asked the right

questions and provided their own engineering ideas to help us achieve our

objectives. Because space couldn't accommodate a continuous loop line, designing

the conveying system proved particularly challenging, as did the relatively slow

50-minute Total Average Cycle Time (TACT) required for the low - eight engines

per shift - production volume and the 'no-faults-forward' culture.

To meet the specification within the space available Exmac designed a compact

10-station back-to-back manual line that takes up very little floor space in the

new building. The system allows Ricardo to load engine blocks onto the line and

rotate them at any of the stations, and indexes manually to allow greater

control over the assembly process.

Engine blocks are fixed to lightweight trolleys using a vertically mounted slew

ring and quick release plate, that allows it to be rotated through 360 degrees

whilst is locked in place to allow complete access for operators. Engines start

their build sequence at station 1 and when all assembly functions are completed

the control system allows a stop to retract for the operator to push the trolley

(running in a steel track) to a holding position until station 2 is clear. The

trolley is then pushed to station 2 where it is again held in place for that

station's assembly functions to be carried out ...and so on to station 10.

A latched turn-post at each end of the line (providing a swing-gate effect)

allows trolleys be re-directed to the opposite side of the line after assembly

operations at station 5 are completed. When a trolley reaches station 10 the

engine block has been transformed into a fully assembled, complete engine.

The Exmac-designed mechanical locking systems locate and secure trolleys at each

station until the MacDonald Humfrey HMI system confirms that operators have

completed all required tasks at each station, and assembly can continue on a

no-faults-forward basis.

If an engine needs to be reworked, trolley and engine can be moved to a holding

position at the end of the line. When work is completed, both are returned to

station 1 (via the turntable if necessary) and then moved to the appropriate

station to allow the engine to continue its build programme.

Commenting for Ricardo, Dave Thompson says a great deal of thought has gone into

the way the line operates, and has resulted in a number of innovations,

including a novel low-cost method of rotating the engine using a

battery-operated electric drill, fitted with a special socket that is attached

to the gearbox, enabling the engine to be positioned wherever it is needed.

The bespoke MHA Human Machine Interface' provides Ricardo production engineers

with a list of operations that they can vary and configure themselves. For

example, not only are they able to set task-by-task instructions showing

assembly operators how to build the engine, they also include time allocated to

each task, DC tooling operations, air tests, and gasket glue plotting. In

addition, the HMI integrates all operations and confirms - with a time and date

stamp - that all tasks have been completed. Effectively this means that every

single operation - including every bolt to be tightened - has its own programme!

Detailed on-screen information and visual aids are shown at each of the ten

stations and data is fed to an MHA pick-to-light system to ensure efficient

error-proof component picking.

The facility was specified, designed, constructed and commissioned in just 18

months despite Ricardo insisting on an aesthetic approach to the design, in

order to present an attractive and technically advanced visitor environment for

Ricardo's international customers.

Summing up, Paul Crosbie of MHA says: "The combination of a robust Exmac

handling system and complex MHA control system, has more than exceeded Ricardo's

overall performance expectations."

For further information contact:

Marcus Hunter, Exmac Automation Gregory's Bank, Worcester WR3 8AB

Tel: 01905 721500, Fax: 01905 721539

Email: http://MH@exmac.co.uk, Web: www.exmacautomation.co.uk

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