HomeRail NewsClass 317 - half old, half new

Class 317 – half old, half new

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When The Rail Engineer last saw train 317722, it was parked in a corner of Bombardier’s Ilford depot (issue 98, December 2012). The interior was missing from two carriages, all of the traction equipment was out from under the frame, and it looked quite forlorn. In fact, this was to be the new Class 317 demonstrator for Angel Trains. It was one of nine 4-car units last used by Stansted Express which have been in storage since early 2012.

The plan was to show how a total refurbishment could change a train. So two cars were being left as they were – the Stansted Express seats had been covered in plastic sheeting to protect them. The other two cars would be completely refurbished and the contrast between old and new would be easy to see.

There would be other changes as well. Out of sight of the passengers, the old DC traction system would be replaced by a modern AC one and various other technical improvements were planned.

Smart new interior

Twelve months later, and the project is almost complete. The Rail Engineer caught up with 317722 again while it was undergoing final test at Bombardier’s Derby factory. Stuart Benford, Angel Trains’ project manager, and Peter Keighron, his Bombardier equivalent, were also on hand to explain just what they had done to the train behind them.

“The 317 is a good unit,” Stuart started off. “It’s not in the first flush of youth, and there are some features that needed improving, but the basic train is sound and quite capable of giving many more years of service.”

Apart from the smart new paint, the most obvious change is the interior. Comparing the two ‘new’ cars with the two old ones is like 01773 852277comparing chalk and cheese. The original Stansted Express carriages are dark and old-fashioned. In contrast, the two that have been refurbished are light, airy and somehow seem to have more room.

Part of that may be down to the seats. They are identical to the ones currently being fitted to new Class 377 trains at the Derby factory – in fact, there is a rumour that a production manager is still looking for two sets of seats that seem to have been ‘misplaced’!

The vestibules are also very different. Gone are the large luggage racks from the airport services, and spaces around the doors are now larger and more open. However, due to the thinner backs of the new seats, there has been no change to the number of seated passengers overall.

Additional details

LED lights brighten up the interiors as well, and the carriages are now PRM (Persons of Reduced Mobility) compliant. With passenger information systems included, the carriages now have all the features of a new train.

As this is only a demonstrator, the original hopper windows have been retained. However, these can always be changed in the future if the operator requires.

Some other small details have been improved as well. One problem with the doors is that, in autumn, leaves get carried into the carriage on passengers’ feet. These then get trapped in the doors and carried into the door pockets buried behind the panelling of the carriage. From there, it is a devil of a job to remove them. As part of this refurbishment, much larger access panels have been fitted to those pockets, so making life easier for hard-pressed depot staff.

Under the frame

Those door pockets are not the only hidden improvements. Major work has been undertaken on the drive train to make significant changes.

Gone are the old DC traction motors. “DC motors are not as good as AC,” Peter Keighron explained. “They don’t regenerate, and they don’t like winters.”

Working with Bombardier engineers from the propulsion centre of excellence at Västerås in Sweden, Peter’s team have developed a special version of the proven MGA280 motor. This fits exactly into the same mountings as the original DC motors, so no modification is needed to the two power bogies.

Class 317 trains have one power car, with two power bogies, and three trailer cars. Of course, the half-and-half approach that the interior received is not applicable here – the entire traction system has been replaced and both driver’s cabs modified to suit.

All of the new control equipment fits under the frame of the power car, but that leaves no room for the battery pack which has to be moved to the adjacent carriage.

01773 852277“This is all proven technology,” Peter commented. “The traction package is similar to that which we use on both London Underground’s new S-Stock and on our Electrostars. It is also used on the Delhi Metro.”

In theory, the new AC motors would be more powerful than the originals. However, as the trains are used in multiples to make up eight and twelve-car consists, the performance of the modified units has been engineered to be similar to those on unmodified trains.

Similarly, the control system has to be compatible so that units can be coupled together and driven from either one cab of this train, or one cab of an unmodified one. However, the new motors will have more tractive effort and will accelerate for longer, reaching the top speed of 100mph more quickly.

In the cab, the only change to the driver’s controls is that the panel now contains a gauge indicating the performance of the regenerative braking.

Final testing

After the unit has been tested at Derby, both in the laboratory and on the short test track, it will be given its first run on Network Rail infrastructure. This programme will be conducted out of Ilford during the night in a signal protection zone (SPZ). Greater Anglia drivers will undertake the tests with a view to the train entering passenger service in February 2014.

Once Abellio and its passengers have experienced the unit in normal service for several months, Angel Trains will then be able to assess how best to offer Class 317 trains to future franchise holders in the Greater Anglia and other regions.

When asked whether it is worth all the effort to refurbish an old train to such an extent, Stuart Benford is in no doubt. “Despite all the work we have done, this train can be leased out to an operator for half of the capital cost of a new one. There is good life left in it yet, and it makes perfect sense for us to rework these trains so they can work more efficiently and economically for the duration of the next franchise.”

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  1. As the Class 321 Demonstrator train is heading back to Ilford Depot. A Demonstrator Class 317 is also heading back to Ilford Depot. About time to improve these trains. Class 315 have already been refurbished but soon are to be moving to Wales because of Crossrail having new trains.

  2. Interesting article and subject. Unfortunately, one mistake. The remark made by Peter Keighron about DC motors is not true, they do regenerate. Proof of this are, amongst others, trains (SGM2 and 3) with DC choppers running in The Netherlands and metros in Mexico.


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