Taking stock

A new strategy with a modular approach to train design has put Adtranz back in the driving seat. Anthony Gould details the reversal of fortune

Train maker Adtranz UK is back on the rails after a three-year drought in new orders. During this period it managed to preserve its core skills and put in place a strategy which has now paid dividends, the company pulling in £330m of orders for new rolling stock in the past four months.

Manufacturing rolling stock these days, concedes Dee Razdan, engineering director at Derby-based Adtranz UK, is all about ‘customising a tube’, with the plant capable of producing 17 product variations from the same concept vehicles.

The turnaround in the company’s fortunes has been the result of ‘a massive step change for the industry in design and working practices’, explains Razdan.

‘Traditionally trains made for British Rail were built to very detailed specifications and often carried unproved, untried and untested technology, and hence were unreliable. Not one train built 25-30 years ago actually conformed to its design drawings,’ says Razdan.

‘Following the privatisation of British Rail, the new customers, the leasing companies, are interested in getting bums on seats and want a lower cost product with higher reliability. That is, the customer is now interested in the hardware needed to deliver a reliable service.’

Two years ago, in the middle of the three-year drought for rolling stock orders, Adtranz put a strategy into place to meet the new demands. It knew, from messages filtering up from the sales force, that the privatised rail industry would not only be more interested in business plans than detailed engineering, but would also need constant support and maintenance packages.

‘The challenge as an engineering department was that we needed standard, proven, tried, tested and low cost trains,’ he says.

The chosen option, and one also adopted by Adtranz’s UK rival, GEC Alsthom, was a flexible modular product with proven subcomponents.

Adtranz has developed four concept vehicles: a multiple unit, a metro, an automatic guided train/light metro and a tram.

The core train remains unchanged but is adapted to meet the wishes of customers who want different colour schemes, front ends and so on.

‘Our challenge was to analyse what interface problems these changes could create, and to manage them. We needed to look at how the seats interact with the car. Our concept was to put a continuous seat rail in the body side and the floor to give an infinitely variable pitch.

‘We also opted for a mechanically fastened front end to our vehicles, so we can develop, prove and test a cab completely off the production line – providing many manufacturing benefits. The customer gets a proven product in the shape desired – and we can change the front end in a short lead time.

‘Building in flexibility, say in choice of air conditioning options, demands thorough analysis, and consideration of manufacturing capabilities at every stage of the design process. You can get a lot of availability but without the same reliability. The more units you offer the greater the chances of poor reliability.

‘With a high availability/high reliability target, we needed to minimise the number of components and ensure that these are more reliable than in the past: that means only using proven technology,’ says Razdan. It also entails the plant’s engineering staff being involved in the design process from the start.

‘From a marketing point of view, the move to business specs is a double-edged sword as the customer gives so little information that it is often hard to work out exactly what it is you should proffer in your tender. Whether they want long or short cars, or are there any constraints in their maintenance depot in terms of size and length of units that can be accommodated, all has to be considered.’

The modular approach can be used for tilting trains – as to be used on the West Coast main line – at little extra cost. All Adtranz’s surface stock is built with a slanted body side to accommodate a tilt with the same product at a later stage.

Although Razdan says the firm is only interested in using proven technology, it is constantly striving to find new solutions to age-old problems. ‘New technology plays an important part in competitive and reliable train manufacturing.

‘It is pointless developing a magnetic levitation train if our customer does not want one.’ Adtranz Europe does have an order for one in Germany on the proposed Berlin to Hamburg Transrapid system.

The major subcomponents that make up the train are all constantly evolving.

Traditional bodyshells made of a steel underframe – as on the the old class 411 and commuter slam-door stock – could soon be replaced by non-metallic structures. ‘In our labs we are testing non-metallic materials for a whole coach structure, and are looking at adhesive bonding rather than welding. We have already gone into laser welding of aluminium.’

The trains being produced are aluminium monocoque constructions with mechanically fastened body-sides, roofs and floors.

Bogey technology is also evolving. Originally, bogeys were big and heavy; then with the Advanced Passenger Train there was a move to the light swing type of design, both tilt and non-tilt. ‘On the Strasbourg tram we have gone for independent wheels. There are no axles on the tram whatsoever, and each wheel is driven independently by a traction motor,’ says Razdan. Adtranz is also looking at new materials for the fundamental bogey structure.

‘On the propulsion side we have gone from DC machines to AC machines, the latest device being the insulated gate bipolar transistor. In the long term we have development programmes looking at permanent magnet drives, so technology may go full circle, back to DC machines but without the commutators, slips, rings and brushes which were the bane of all DC machines in the past.’

Razdan says the company does not really indulge in blue sky research, as cost is a driving factor. But, on the propulsion side, he says, they are keeping a wary eye on superconductivity research.

‘In theory you can create superconductivity at room temperature which means you can get traction motors the size of a matchbox. This may be extreme, but this technology is being demonstrated at temperatures of -150 degrees C. If they get to -50 degrees C we should probably start to look at investing in cooling equipment.’

Razdan says 30-40% of his total budget is speculative. ‘We have had to invest in these concept vehicles, despite having no orders in the past two years. Some of the bids we are tendering for in Singapore and Argentina are also based on these modular vehicles.’

Modern design tools also play a major role. Using virtual reality Adtranz can design a vehicle in Derby, model it, and then the engineers in Sweden can walk around it. ‘We have put a tender into Singapore where we had to deliver a virtual reality model as part of the process,’ says Razdan. ‘It also enables our engineers world-wide to communicate with each other.’

Electronics is also playing a major part in reliability. ‘For every electronic and electrical component on the train, I have a virtual train in the laboratory. The systems integration rig mimics every function the train does electronically and electrically.

‘You have to drive it just as a real train,’ enthuses Razdan. That is, ‘you drive the train in software to make sure all the interfaces are correct. It enables us, for example, to make sure that if passengers push both buttons on a door they won’t open when the train is moving.

‘Software can also prove all our vehicle wiring and harnessing – prone to the greatest number of defects, and one of the most time consuming parts.’ The eight car sets built for the Central Line of London’s Underground have 96km of wiring and harness.

The adoption of the modular approach, and the changes it has brought to the manufacturing and design process, has certainly paid dividends. The three-year drought in train orders from the new privatised railways ended last year and in the past four months, Adtranz UK has taken £330m of orders. The latest two contracts – from Connex Rail for 30 four-car Electrostar trains and Midland Mainline for 13 two-car diesel trains – total £130m. Both include maintenance contracts and options for further units. The orders followed hot on the heels of a recent £200m order from Prism Rail.

The drought is clearly over.