Due care and attention
Alstom has recently completed the ten-year heavy overhaul of the Coradia Class 175 fleet of DMUs for Arriva Trains Wales, costing £9 million.
Traditionally such programmes would have been outsourced to heavy works companies – historically BREL – but Alstom has developed the capability to carry out the work in-house at its Manchester Traincare Centre in Longsight. The fleet’s core maintenance regime is performed at Alstom’s facility in Chester.
The company built and now maintains the Class 175s, which operate from Wales into the north-west of England. There are 27 trains configured into 11 two-car and 16 three-car formations.
They were first introduced back in June 2000, operated at the time by First North Western, as part of a move away from locomotive-hauled coaching stock on Birmingham/Manchester-Holyhead services. This was completed in 2006, by which time Arriva Trains Wales had taken over the operation.
From a fleet of 27 trains, Alstom provides 24 for service Monday-Friday and 23 on Saturday-Sunday. An additional train is also supplied at weekends during August and over bank holiday weekends.
Manchester Traincare Centre at Longsight was chosen for the overhaul both for geographical reasons and the range of its existing facilities. These are used to carry out maintenance on various types of traction and rolling stock, including the primary contract with Virgin Trains for its Pendolinos until March 2012.
Alstom also acquired the contract extension with the Department for Transport and Angel Trains for the supply of 106 Pendolino vehicles, and their maintenance, to 2022.
The Manchester & Birmingham Railway opened its line through Longsight in 1840 and built the original depot there in 1842. The first modern shed was erected in 1869 and was brought into use a year later.
Brick built with hipped roofs, it featured 12 roads. In the early 1960s, the Electric Traction Depot was built there to maintain 25kV AC EMUs and locomotives. Both 1999 and 2005 saw considerable changes as part of moves to accommodate the Class 390 Pendolinos.
Principal customers at the site are Virgin Trains, Northern Rail and Bombardier Transportation.
Out with the hammer
Alstom has been steadily raising the bar in its performance since it took over the West Coast Main Line depots, moving from a hammer to laptop culture, ensuring the required train reliability and availability to Virgin.
The company’s production system APSYS, harnessing methodology based on ‘Lean’ manufacturing and Kaizen principles, is a common way of working across all sites to eliminate or reduce waste, bringing quality, cost and delivery commitments with sustainable and efficient common practices.
Alstom has also adopted a ‘5S’ methodology, encompassing –
- Sort – sort out unneeded items
- Straighten – have a place for everything
- Shine – keep the area clean
- Standardise – create rules and standard operating procedures
- Sustain – maintain the system and continue to improve it.
Also implemented has been a Lean maintenance approach in all operations with –
- Improved tooling, equipment and facilities within the workplace
- Better workplace organisation thanks to ownership and responsibility placed within the maintenance teams
- Enhanced maintenance processes with workflow models, thus eliminating waste
- Comprehensive indicators measuring, reviewing and actioning work rosters that align with workloads, such as matching resources around workload patterns.
In July 2010, the ten-year heavy overhaul programme started at Longsight where use of an existing bogie overhaul facility – previously created for the Pendolino – could be further used for the Class 175 fleet. That programme took 45 weeks to complete.
In order to reduce the amount of time each unit was out of service, as many systems as possible were aligned to coincide with the bogie works. So the scope was broadened to include overhauls of the auto-coupler, cooler group and gangways, together with an underframe wiring rework and interior refresh which involved new seats and carpets.
All this was completed during the same down-time period, taking place in seven days for a two-car set and ten days for a three-car. The programme has seen 420 modules, 137,500 consumable items, 7.5km of underframe flexible conduit and 4.2km of saloon carpet fitted.
Alstom’s focus has been to ensure only one train is away for overhaul at any one time and avoid any three-car sets being out of service during peak periods, whilst also maintaining contractual availability at all times. Individual trains were transferred from Chester Traincare Centre to Manchester on Sundays or Wednesdays.
Certain project events were implemented in the planning stage to facilitate improvements to maintenance practices and the logistical process. These included –
- Four individual five-day APSYS events to identify and implement process improvements
- £250,000 invested in Class 175-specific tooling and equipment, of which the majority will be taken back to Chester to support ongoing/future activities, such as two cooler group tables, three engine raft tables, an auto-coupler jig and counterbalance
- Removal and refit of the engine raft completed during a Kaizen event, producing standard operations and reducing labour costs.
The fleet’s overhaul, modification and interior refresh programme was completed on 18th May. It has ensured robust availability and a continual improvement in reliability. Historically the 175s have suffered from alternator failure during winter periods but, despite last winter bringing prolonged severe weather conditions, no such failures occurred on overhauled trains.
A year ago, prior to the programme, reliability stood at 13,400 miles per event. This is calculated using the National Fleet Reliability Improvement Programme’s Moving Annual Average and represents the fleet’s total mileage over the previous 13 periods divided by the sum of all technical five-minute delays during that time.
The contractual target is 13,500 miles although Alstom aims for 20,000. The figure currently stands at 15,500 miles, representing an improvement of 15%.