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New high output track renewals plant for Network Rail

Posted: 2 March 2005 | | No comments yet

Network Rail’s first new high output ballast cleaning system from Plasser & Theurer, delivered to time and budget last summer, has begun work on the Great Western main line which links London to Bristol and South Wales. It is the first of a series of new high output track renewal machines, with a total value of £90 million.

The UK rail infrastructure company is investing £3.3 billion in track renewals up to 2008/09, at the same time as the whole company pushes forward delivery of 30% cost efficiencies. Amanda Henderson, Network Rail’s Senior Project Manager for Track Renewals, says step changes in delivery methods will be needed and high output track renewal is going to offer them. “Delivery of quality track renewals is going to be absolutely critical to the future performance of the railway.”

The Plasser & Theurer RM900 high output ballast cleaning system now in use by Network Rail is the first of two ordered – each one worth about £25 million. The first system is being operated and maintained by First Swietelsky, a joint venture between First Engineering of the UK and Swietelsky of Austria.

A £17 million Matisa P95 high output track relaying system has also been ordered, with sleeper carrying wagons manufactured by WH Davis, and will also be operated by First Swietelsky.

Support plant, representing an investment of just under £20 million, forms an important part of the high output system approach. Network Rail is buying three Plasser & Theurer 09-3X Dynamic combined tamper/dynamic track stabilisers, with an option for a fourth, and also two Plasser & Theurer USP5000 ballast regulators, with a third expected to be ordered.

The high output ballast cleaning system comprises the high output ballast cleaner itself, with a fleet of specialist ballast and spoil handling wagons. There are 44 of these MFS wagons, also from Plasser & Theurer, in each of the Network Rail RM900 systems – eight of these have slewing conveyor belts for unloading spent ballast. There are also two power wagons to move the wagons on site. Four multi-purpose wagons manufactured by WH Davis act as barriers for projecting conveyors and are equipped with brake valves to control propelling moves on site.

Plasser & Theurer’s Norbert Jurasek said one of the main challenges in producing the RM900 for the UK was to fit the design to the British loading gauge, while maintaining the material flow – more material wagons have been required to match the required output rates. He said good teamwork with Network Rail from the earliest stages has eased the production and introduction of the plant, and refinements made on the first machine (to such areas as ballast screening and safety guards) are being applied as the second machine is built.

Ballast cleaning is a mechanised process to remove degraded ballast, or ‘fines’, while keeping the track in place. Excavated ballast is passed through vibrating screens to sort the fines which are conveyed forward to spoil wagons. The larger pieces of ballast from the screens are placed back into the track. New ballast is fed from wagons at the rear of the train to make up for the removed material. Following behind, a tamper/dynamic track stabiliser and ballast regulator consolidate and stabilise the formation.

Three systems

Network Rail will own three systems of high output track renewal equipment when the new orders are complete:

  • The first new RM900 ballast cleaning system with the Matisa P95 track renewal system
  • The second new RM900
  • A Harsco track renewal train with medium output ballast cleaners

The Harsco track renewal train and two Plasser & Theurer RM95 medium output ballast cleaners are in use on the West Coast route modernisation programme. Though not at present used in production line mode, the RM95s are capable of working in this way (like the high output machines), covering up to 250 metres per hour as against 440 metres.

Further new Plasser & Theurer equipment has been ordered for the UK network by First Swietelsky. The £3 million order is for new advanced track finishing systems, providing combined ballast profiling, regulation and dynamic track stabilisation. The two machines are the first of any kind to be bought by First Swietelsky, and are a first for the UK infrastructure, which has no current track finishing capacity.

The systems, due to start operations in early 2006, are unique to the UK, and have been specially designed to provide high output delivery, with flexibility for maintenance and renewals work. They will be capable of working throughout the European network. The machines will have water damping systems to minimise dust and provide environmental control measures. A ballast laser profiling system will allow measurement and quantification of ballast profiles, providing unique identification of quantities and accurate track stability measurement. They will also have a sophisticated track geometry measuring system for control of finished track geometry. A high capacity ballast hopper, carrying over 30 tonnes of ballast in transit, will give three times the carrying capability of other regulators.

First Engineering is also investing in three Kirow Leipzig cranes to support both its track and projects work.

High volume, cost down, quality up

Network Rail’s Colin Ness explained that its objectives for high output renewals are to increase capability on main lines with limited track access, to be very efficient in the way the work is undertaken – reducing unit costs, and improve the quality of the work – bringing whole life cost benefits.

The intensive utilisation of specialist plant in a production line manner – like a travelling factory – means that work is undertaken on very long sites, several kilometres of track at a time. Colin Ness said the key to successful high output is building a plan founded on repetition, both of logistics and production plans. “We need suitable sites, suitable track access and really high quality logistics to make high output work.”

The high output teams face the challenges of delivering track renewals three or four nights during the week, achieving a 24 hour turnaround to deliver track renewals the next night – then turning out to do a weekend shift.

First Engineering Track Group Managing Director, Steven Bell, says that First Swietelsky’s role is to make the new Network Rail equipment work and make it work very well – not just the plant but the logistics operation that goes with it. “We must work as part of the integral team that includes core operations – with key players from Network Rail, train operators, key control centres, and our haulier Freightliner.

“It’s absolutely crucial for the midweek works that the whole system works well, so that we handback at the agreed line speed – the focus has to be end to end, not just on the big item of plant at the centre of the system.

“Planning of enabling works is critical to the rolling programme – we need to carry out advance checks on the infrastructure over a year ahead to ensure we take account of such elements as cabling, undertrack crossings and structures.”

The Network Rail routes which are expected to see high output techniques used in the future are the East Coast, Great Western and Midland main lines, the West Coast main line, the core section of the main Cross-Country route, and perhaps some important secondary routes.

The Phase One programme of high output track renewals, using the high output ballast cleaning system and track relaying system, focuses on the Great Western main line, where it represents the greatest concentration of track renewals on the route since the early 1970s when it was the first 200km/hr track in the UK, prepared for high speed train services.

The output target for the RM900 is to achieve 130km of ballast cleaning a year at full production. Typically the system will work three mid-week production shifts of around eight hours (around 600 metres of track can be cleaned per shift) and one weekend shift of typically around 16 hours (around 1,400 metres cleaned), for 44 weeks a year (176 shifts).

The ballast cleaning system moves to site as one very long train, with a crewed locomotive at each end, and is designed for a maximum of about 100km/hr while in transit. At its maximum planned length, the gross weight will be 3,200 tonnes at most, and an overall length of 788 metres. A lot of planning has to go into how big the train can be and how it is operated on the network.

At the end of a shift, the train is split into parts, spoil is taken to be discharged, and separately the ballast wagons go to be loaded. The train also has to be cleaned, maintained, fuelled (at several different points along its length) and joined together again. A new depot giving the required space for the long train, and flexible access to the main line, has been provided at Reading at a cost of about £3 million.

Track access is a critical requirement for the high output techniques, but capacity on the UK rail network is at a premium. Network Rail’s team is at pains to stress that efficient renewals cannot be at the expense of train operators and their customers, and is engaging in dialogue to find the right balance for occupation of the track.

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