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ElevArch – an intriguing concept

Overheard at last year’s Most Interesting awards in Derby was this brief snippet of conversation: “Really?”… “That’s an intriguing concept.” Perhaps this would have been lost in the general hubbub of networking going on but for the obvious height- of-eyebrow-raising on the “Really?”, the splutter on the gin-and-tonic and the narrowing of the eyes accompanying the guarded reference to ‘an intriguing concept’. Could this have been, in fact, a lightly coded and polite version of “You’re off your trolley pal!”?

But, of course, surprise is everything. Reactions such as this are understandable when, out of the blue, a proposal to lift an entire brick arch clear of electrification wires is made – and made in all seriousness.

The background

Let us look, then, at the background to all of this. Why is such a concept being considered at all? After all, electrification schemes have been progressed for several generations already. Plenty of structures have been in the way and there are several well-established methods of getting round most of the problems.

These have involved either lifting the bridge or lowering the track – except that, in the case of brick or masonry structures, lifting has been seen as far too ‘intriguing’.

In short, it’s never been done before.

And why hasn’t it ever been done before? Let’s just consider what a brick arch consists of. It’s essentially just a pile of bricks carefully (usually) arranged in a specific order to hold itself up with some spare capacity to carry a little extra. If the structure is disturbed carelessly, then it will revert back to its original form of a pile of bricks – but this time the process happens very quickly. Not for nothing are they called gravity structures.

It’s not been done before because, for most engineers, it is all much too… adventurous… or even reckless.

Plain logical

But for one man, Bill Harvey, a well known and respected expert in brick and masonry arches, lifting an arch was just plain logical.

So long as the line of thrust is kept within certain parts of the arch ring then it will be possible to keep the whole structure stable. Arches may seem to be heavy, but modern jacking technology is perfectly capable of coping with the weight involved and with the required precision needed to manipulate the structure.

Bill knew that. Bill knew that over ten years ago! Understandably, others were less enthusiastic.

So what has changed? In one way, nothing. The physics are the same, the lifting technology is the same. Electrification and its disturbance of civil engineering structures is the same. But many disparate issues have all come together. The industry is more aware that, of all the costs of electrification, 25 per cent is spent on altering civils structures. Society is more appreciative of heritage structures, and wholesale demolition, which could occur even in World Heritage sites, is now actively questioned. Add to all this the disruption to train services in most of the normal methods of ensuring electrification clearances, and it becomes clear that there is a need to add a further option.

Summary demolition

The existing methods – as have been referred to previously – include track lowering, which may lead to long possessions and the disturbance of foundations. Deck raising has hitherto only been used for steel or concrete structures. If brick or masonry structures are in the way they have been summarily demolished.

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Up to the 1970s, and maybe slightly later, the preferred option was simply to blow them away. It was preferred because it was quick – very quick – and, let’s be honest, really exciting! But carrying around and using explosives seems to have fallen out of favour.

More recently, demolition by specialised long-reach hydraulic peckers and nibblers has been very effective as they can be controlled with some element of precision. Whatever demolition method is adopted – exciting explosives or clinically efficient hydraulics – the end result is much the same. There is a pile of bricks that has to be loaded away without damaging the tracks or the signal cables.

Trying out an idea in real life

RSSB, in association with Network Rail, ran a competition in February 2014 with a view to finding a way of avoiding the disruption caused by the demolition of arch structures. The nature of such a competition is to bring together people and companies who may find that they have similar aims and facilities but who just need some seed cash to try out an idea in real life.

Such was the case with Bill and his concept. It really was a matter of cometh the hour, cometh the man, cometh the company (Freyssinet), cometh the combined proposal, cometh the business case and cometh a successful bid for a trial on a real bridge.

Freyssinet is a civil engineering company that specialises in the repair and strengthening of structures. It also has a reputation for moving things – at times, very large things. When Kevin Bennett and John Kennils of Freyssinet met Bill at the competition networking session, they immediately realised that the brick arch raising project was bold, but achievable – and definitely something they wanted to be involved in!

It is not easy to find a practice bridge, but one fitted the bill on the mothballed East -West route near Milton Keynes. Moco Farm bridge is a simple single span brick arch carrying a narrow farm track. It was built in 1850 for the line engineered by Robert Stephenson. It has a clear span of 10.1m and appeared to be in reasonable condition. It was also in the back of beyond.

The farmer was amenable to the trial and a temporary access road and level crossing was installed so that his daily activities and those of his herd could continue unhindered.

Carefully does it

The bridge was thoroughly examined, its parapets were stabilised and, gradually, the fill was removed down to the barrel of the brick arch and the abutment chambers. This was like shaking hands with the original craftsmen as the original framework of the structure was carefully exposed, with construction details very close to those on the original plans. But, as is so often the case with structures of this age, there were a few surprises. Separation cracks that seemed small on the outside were not so small within the body of the structure. Brick headers in the parapet did not carry through, but were what is known as snap-headers – effectively a cheat by the brickies.

In order to be sure that the arch, its spandrels and abutment diaphragms stayed intact, a number of strengthening measures were taken. Belts and braces were in evidence, but why not? This was a world first.

The next challenge was to separate the arch, spandrels and parapets from the footings to allow the whole superstructure to be lifted – or rather, to be jacked up.

Vertical and horizontal components

At this point, fundamental engineering comes to the fore. The precise line of thrust from the arch can be a little vague. It will be within certain limits, but the best way to cope with this variation is to resolve the thrust into vertical and horizontal components.

The vertical is relatively simple and can be accommodated with the jacking system.

The horizontal is taken by a pair of vertical slide plates inserted in a vertical groove in the four wing walls. Above the slide plates, the grooves are angled back to allow the arch to rise without becoming snagged.

Centrally controlled hydraulic climbing jacks are located at each corner and at mid points on the abutments and the abutments horizontally separated with a wire saw cut.

Precise monitoring is carried out, so making sure that every jack rises at the same rate. In addition to an impressive array of electronic sensors, there was a fallback in the form of a water level. This is something that would have been familiar to the builders of the pyramids.

Live demonstration

On Thursday 26 October, the industry was invited to a live demonstration of the lift and, of course, Rail Engineer was there. Quite a crowd had answered the call, mainly of people and organisations interested in witnessing something rather extraordinary and something very brave.

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The Railway Heritage Trust came along, as there is now an alternative to the wholesale destruction of heritage brick arches. A raised arch will mean a raised parapet and possibly raised string courses, but there are legitimate ways in disguising cut lines in existing vertical features.

Others at the demonstration included representatives of design houses charged with solving many of the usual problems associated with electrification and structural clearances.

The ElevArch team – that’s Freyssinet and Bill Harvey – acknowledge that this technique is not the only option to solve the issue of brick arches, but it does bring to the table another way of doing things and one that can be considered as a legitimate technique along with track lowering and demolition.

And what of the live lift? While some may have been sceptical and some downright doubtful, awaiting with glee to witness a new pile of bricks, Bill and the Freyssinet team were more relaxed than many had anticipated. At about five minutes for every 100mm lift and a pause for re-packing the jacks, the process is not fast. It does not need to be. With all the preparatory works being carried out behind safety barriers and without the need for possessions, the only blockage needed to complete the lift could be just a normal rules of the route possession. Six hours would be sufficient to mobilise the jacking system and to complete the series of 100mm lifts and inspections.

The demonstration bridge was lifted a total of 900mm to demonstrate the scale of what is achievable by this patented technique.

Once in position, the jacks would be removed for reuse, the vertical slides would be grouted in and the whole structure gradually reinstated but with the deck at the new required height.

Confidence

So yes, the live lift was a success. Lifting a brick arch is possible, although Bill never doubted it. The ElevArch team knows that the technique can be improved still further. The aim is to get a feel for what preliminary works are really necessary and to ensure that the exercise is commercially viable. The rail network has about 500 such bridges, although not all are contenders for ElevArch.

It will be interesting to overhear the conversations at the next Most Interesting awards in Derby. The ‘intriguing concept’ has proved itself. No need to choke on the gin-and-tonic this time.

Written by Grahame Taylor

Building blocks

Anyone who has walked barefoot into a child’s room late at night will probably hate Lego bricks. That aside, Lego has got to be one of the best toys ever developed. It’s an open system with which you can build whatever you want. Lego took the simple wooden cube and turned it into a building block of the imagination. It’s a powerful thing for a child to realise that they can think of something and then create it. One wonders how many of today’s engineers have started that way?

What goes around comes around. High on the moors in Cumbria, near the border with North Yorkshire, building block modelling has taken on a new relevance. Near the southern portal of Risehill tunnel, on the Settle and Carlisle line, a drainage problem has been rectified with the aid of those pesky little bricks. Not literally, you understand, but they were used in the development of an intricate concrete structure built from – yes, that’s right – interlocking blocks. And it’s pleasing to learn that the definitive Lego model was taken to site as a source of reference!

Water everywhere

On the Settle and Carlisle railway, dealing with the problems created by excess water has been ongoing since the line’s inception. That’s what you get, of course, if you run a railway through the high Pennines, but then climate change hasn’t been helping much of late.

The Eden Brows landslip (issue 143, September 2016) is a case in point. Indeed, the remedial drainage works at Risehill have been completed, under a framework contract, by the same company that is undertaking operations at Eden Brows – Story Contracting.

Just south of Risehill tunnel, the railway is carried on an embankment. A stream known as Cowgill Beck flows in a large culvert built on the skew through the base of it. In this vicinity, rainwater had been collecting which threatened to destabilise the embankment. A three-pronged solution was put in place to create a permanent solution to the surface and ground water problems and then to strengthen and protect the embankment.

Logistical challenges

The location is wild and remote, so before any of this work could start it was necessary for Story Contracting to lay a 1.4-mile haul road. Making partial use of an existing forestry road, it traversed a plantation, known as Dodderham Moss, from the so-called Coal Road near Dent station – the highest station in England at 1,150 feet above sea level.

This unclassified public road is narrow and twisting, with very steep gradients. Not for nothing is the approach from the valley to Dent station called the Corkscrew! Even just getting plant equipment and materials to the worksite therefore presented difficulties, with all heavy vehicles having to approach along the Coal Road from the direction of Garsdale.

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The largest item of mobile plant – Story Contracting’s 22-metre long reach excavator – had to be driven on its tracks from Garsdale station, a distance of over three miles to the start of the haul road. Over all of this distance, the road surface required protection from the vehicle’s tracks.

Staged approach

The work on site was divided into three phases. Starting in the early summer of 2015 and continuing until December 2015, the ‘Dodderham’ drainage works mitigated surface water and groundwater problems around the southern portal of Risehill tunnel. Concurrently, the ‘Risehill Up Side’ drainage scheme dealt with similar problems to the east of the tunnel approach embankment. Extensive land drainage schemes were installed, all emptying directly into Cowgill Beck.

Work recommenced in July 2016, under the title of ‘Dent Embankment’. This third scheme, to be completed within just a two-month time slot, commenced with the stabilisation of the embankment at cess level over a distance of 62 metres on the Down (western) side.

Stability here was achieved by means of a ‘Kingpost Retention Wall’. This involved driving hollow 339mm diameter steel piles, installed at two metre centres and reaching a depth of seven metres. The piles were filled with site-won aggregate, with the top 1.5 metres being capped with concrete.

Cess retention was achieved by bolting 25mm thick vertical steel road plates to the tops of the piles. These are sunk to a vertical depth of 1.25 metres. The piles were also used as the anchor points for a continuous handrail.

Slump

Important as this work was, the main action was to occur at the foot of the embankment. The slumping of the cess and problems with track alignment were symptomatic of movements occurring due to instability at the toe, with resultant slope failure. And the cause was easy to see – scouring caused by the fast flowing Cowgill Beck.

Reconstruction of the lower slope of the embankment was required and, cleverly, the planned mitigation was linked with the construction of a complex river weir. When the river flows in spate, this large concrete construction has been designed to slow the stream flow around the base of the embankment. Additionally, it incorporates a substantial retaining wall that supports the repaired slope above and protects it from erosion.

Kit built

The water flows through a channel-shaped revetment structure that has increasing width and which falls with four distinct weir levels. Bevelled concrete protrusions from the revetment are designed to impede the water flow. With limitations on the size of vehicles hauling to the site, it became clear at an early stage that the complex weir and water channel would have to be constructed offsite and assembled as a kit – enter the Lego set. Or to be more accurate, enter LegatoTM.

The design work for the project was undertaken jointly by Story Contracting and engineering consultant AECOM. With the worksite being pretty much in the middle of nowhere and sited within a deep ravine, in-situ concrete pours were ruled out. The decision was therefore taken to use pre-cast concrete interlocking blocks to construct the weir and retaining wall. Elite Precast Concrete of Telford is a specialist in this field and produces many ranges of interlocking blocks, troughs, anchor blocks, barriers and posts. Its Legato range seemed ideal.

Scale

Is it a coincidence that the name sounds similar to those smaller plastic blocks we know so well? Apparently, it is derived from the Italian ‘legati’, meaning ‘joined together’. Lego on the other hand is thought to come from the Danish ‘leg godt’, which means ‘play well’.

You can take your choice on that, but the name isn’t the only feature of familiarity. The overall proportions and the concept of male and female jointers mean that this product is like an adult version of the kiddie’s Lego brick. There’s nothing toy-like about them of course, weighing in at up to 2.5 tonnes each and formed from high strength (50N/mm2) concrete.

Modelling the concept in Lego bricks sounds like a joke at first, but not so. With similar proportions to the concrete version, it made every sense. In fact, so useful was the Lego model that it became a three dimensional source of reference on site. It was also used as a briefing tool.

By using the Legato product, AECOM was able to design a weir and retaining wall that is essentially self- supporting. There are no tie-bars or other fixing methods binding the structure together. Wet concrete was used to form the foundation, but thereafter it was just a matter of building up a kit of parts. Each block has a lifting eye cast into it, making the site work even easier. In total, some 245 blocks were used on the project.

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Contained

The Dodderham drainage scheme had involved extensive excavation. Rather than transporting the won materials off site, they were used to grade the access to the Dent Embankment scheme within the Network Rail boundary. Although it was necessary to transport blocks and materials into the site, no excavated materials have left it. In view of the narrow roads in this area, this was an important design consideration.

Building a weir in an active brook isn’t the most straightforward of projects. What happens to all that water?!

The answer in this case was to over-pump it. A ‘water retaining structure’ (a dam to you and me) was created at the outflow from the embankment culvert. Carrying out this scheme during the high summer was an obvious necessity, but even then things didn’t go to plan. With the British weather being what it is, the site bypass pumping was overwhelmed on two occasions. Each time, the resultant setbacks amounted to about three or four days of lost work.

Deflection

The embankment retaining wall is substantially built, again using the interlocking Legato block technique. As well as supporting the embankment, it acts as a water deflector when the stream is in spate. A porous pipe, wrapped in geotextile material, runs behind this wall to drain the embankment toe. It empties into Cowgill Beck downstream of the weir. The embankment toe behind the retention wall, including the erosion gully, was extensively excavated and then re-graded with rockfill.

The entire three-part scheme was costed in at £2.4 million. The isolated nature of the worksite and the difficulties presented by the terrain and the weather has meant that some lateral thinking was required. The engineering solutions produced by Story Contracting and AECOM are a credit to both organisations.

Rhiannon Price, project manager for Network Rail, said: “The work that the team has carried out at Dent will make sure that train services will be able to run safely and more reliably on a remote and iconic section of railway for years to come. There were a number of challenges that the team faced in completing this, not least the environment where the site was located. The roads were narrow and winding with some very steep gradients. However the staff overcame these physical obstacles and the end result is quite impressive.”

She is not wrong!

When Story Contracting completes its work at the Eden Brows landslip site in March 2017, the Settle and Carlisle line will be once again be a strategic through route, and will be in its best ever condition.

Huddersfield’s rolling rig

The Rail Supply Group (RSG), formed in January 2015, is a collaboration between Government (Department for Business, Energy and Industrial Strategy and the Department for Transport) and the UK rail industry. It aims to strengthen the capability and competitiveness of the UK rail supply chain, which employs 124,000 and makes an annual contribution of £3.8 billion to the UK economy.

The long-term vision is to both ensure that the supply chain can exceed rail industry requirements and capitalise on export opportunities with the intention of doubling rail exports by 2025. Currently, only 10 per cent of the rail supply chain’s income is from exports compared with 50 per cent for German rail companies.

RSG launched its industrial strategy, Fast Track to Growth, in February. This is divided into four principal areas: creating the right market conditions, addressing the skills gap, encouraging export growth and supporting innovation. In this respect, the strategy addresses the barriers of limited R&D investment, time- consuming product approval, risk aversion, high barriers to entry and insufficient UK testing facilities.

IRR and CIR

The University of Huddersfield officially opened its Institute of Railway Research (IRR) in April 2013. Its director, Professor Simon Iwnicki, had been at Manchester Metropolitan University’s Rail Technology Unit which specialised in vehicle dynamics and rolling contact fatigue. However, with Huddersfield’s offer of better facilities, Simon and his team moved over the Pennines in 2012 and, within a few months, the University had modified its technology building to provide space for the IRR’s laboratory and research offices.

In its first year, the IRR had engaged in undergraduate and postgraduate teaching programmes, underpinned its commercial enterprise activities and won new research contracts. It also agreed a five-year partnership with RSSB worth £1 million per annum to undertake research in railway engineering systems simulation and safety science.

The Regional Growth Fund aims to create growth and employment. In 2014, it made a £4 million grant for the creation of a Centre for Innovation in Rail (CIR) within the IRR. This requires a total investment of £20 million, building on the RSSB strategic partnership with the support of its industry partners: National Skills Academy for Rail (NSAR), Unipart Rail and Omnicom Engineering.

The CIR works with its industry partners and the University’s Business School to form new relationships with innovative small and medium enterprises (SMEs) which are then offered specialist technology and support. This helps them realise the full potential of their services or products so they can be successfully delivered to the rail market. Last month, CIR opened its new £4.5 million railway research laboratory which started with a very large hole in the building’s floor.

Installing the rig

The hole concerned accommodates the frame for the bogie rolling rig and is 12 metres wide, 15 metres in length and five metres deep. It required one hundred and three 450mm-diameter piles, installed to a depth of 14 metres after hitting bedrock eight metres below ground level.

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Creating such a hole in a low building was a particular challenge as the piledriver barely fitted under its roof. This was also a design constraint for the bogie rolling rig’s frame and the overhead crane that operates above it.

Commissioning of the rig required a new sub-station to be installed in the laboratory to power the 0.45MW roller drive motor and a 150 kW power pack for the hydraulic actuators. This has two 75kW electronically controlled radial piston pumps that can deliver 140l/min at 280 bar.

The rig design was conceived by the IRR working with Heinrich Georg, the company that was also commissioned to carry out the detailed design and manufacture. Heinrich Georg, historically, specialised in steel and aluminium process equipment. Today, it also provides custom-built special purpose equipment, including aircraft test rigs.

A particular design challenge was ensuring that delicate scientific instruments, in use nearby, were not affected by the rig. This was achieved by isolating the walls and the 1.1 metre thick reinforced concrete pit base from the rest of the building. In addition, the 150-tonne rig frame is supported by ten tyre-type air springs. These lift the rig by about 50mm until it contacts elastomeric strips above the frame, allowing the effective stiffness of the rig’s mounting to be changed by adjusting the air spring pressure.

Work started on site in August 2015. The rig was substantially complete by July 2016 and will be fully commissioned by the end of the year.

A unique facility

This full-scale bogie rolling contact, adhesion and braking rig combines a large rotating rail drum which can test a complete bogie assembly. Its key components are a two metre diameter drum with two circumferential rails, a bogie turntable to vary angle of attack and a loading frame with actuators to impose body and roll motions on the bogie’s secondary suspension.

Worldwide, there are perhaps a dozen full-scale rolling rigs. The large roller of the Huddersfield rig gives a more accurate representation of wheel-rail contact conditions. This specific combination of features is considered to be unique.

The drum has 90o rail segments, which had to be specially treated as they were bent to ensure their metallic properties were not affected. The segments have variable mountings to simulate varying sleeper spacing. With four different segments, it is possible to test different types of steels. The joints between the segments provide additional dynamic input, which is useful for certain tests, and the rig has a built-in lathe to apply any new or worn rail profile to the roller.

The rig can test a bogie’s lead axle at up to 200 km/h, apply an axle load up to 25 tonnes and accept a braking torque of up to 110 kNm to assess adhesion and braking performance. It can also undertake traction tests of powered bogies. In this mode, the roller’s motor acts as a regenerative brake to absorb the load. Relative to the rollers, angle of attack can be adjusted by up to 60 and lateral displacement up to 20mm. There are 128 analogue data channels, sampling at up to 10kHz, to provide three-axis wheel/rail contact force measurement and a wheel-rail creep resolution of less than 0.1 per cent.

Dr Paul Allen, the IRR’s assistant director, explained that, with these features, the rig offers a very flexible testing facility that is essential to support the diverse nature of the team’s research activities.

Not the only thing

Whilst it is undoubtedly an impressive facility, the bogie test rig is just one of a number of items in the new railway research laboratory.

The 50 tonne advanced dynamic test cell is essentially the top part of the bogie rig. It is used to apply variable forces to any object that has been secured onto the 11×4 metre test-bed using a grid array of M24 screwed holes. A likely first use of the rig will be the accelerated fatigue testing of slab track, which will be subject to variable loads to simulate the passage of trains over a 30 day period. Other possible applications are the fatigue testing of bogie frames.

A six-axis hexapod motion platform can impose vehicle body motions derived from dynamic simulations on various components. This can, for example, evaluate underframe-mounted equipment from a mechanical fatigue perspective or evaluate energy harvesting systems.

The laboratory has a high- performance computing cluster to process data in volumes not possible with desktop machines. Its use includes the development of big data for risk analysis and predictive maintenance based research. The system has 100-core Intel Xeon processors, running at 2.6GHz, with 640GB RAM, and 2.56TB of storage.

Launch event

On the 12 October, Rail Engineer was invited, along with over 100 guests, to an opening for the new railway research laboratory. As is customary at such events, there were a number of speeches. The University’s vice chancellor, Professor Bob Cryan, considered that railways are destined to be more important than ever and was proud to have the IRR at Huddersfield. He joked that construction of its new laboratory had, perhaps, created Yorkshire’s most expensive hole.

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From the IRR, Professor Simon Iwnicki described the wide range of research undertaken by the institute and the partnerships that it has formed. He explained that the IRR “does a lot of research by computer modelling, but that this needs to be supported by testing and that is why what we are showing you today is so important to us”. Dr Paul Allen explained how the CIR was helping SMEs to develop innovative products.

Unipart Rail’s engineering director, Dr Steve Ingleton, was sure that the new test rig, given the lack of UK rail testing facilties, would help accelerate new products to markets. Stirling Kimkeran, Omnicom’s head of technical services, agreed and encouraged companies to use it whilst David Clarke, technical director of the Railway Industry Association, explained how the RSG was promoting innovation as part of its strategy to support the supply chain.

Other speakers were Chris Lawrence, RSSB technical director, Simon Rennie of the National Training Academy for Rail (NTAR) and Richard East, IMechE Railway Division chairman who later unveiled a plaque to open the facility. There then followed a tour of the new laboratory with an opportunity to climb down the vertical ladder into the bogie test rig pit from where it could be fully appreciated.

Huddersfield’s HAROLD

The statue outside Huddersfield’s railway station is of the town’s famous son, former Prime Minister Harold Wilson, who conceived the Open University. It is no coincidence that the IRR have named their new rig HAROLD (Huddersfield Adhesion & Rolling contact Laboratory Dynamics rig).

No doubt HAROLD will help develop new products as part of the drive to make the rail supply chain more competitive. Indeed, to obtain its grant from the Regional Growth Fund, the University had to guarantee that at least 62 jobs would be created (half at the University, half in the supply chain).

It will do so as part of the UK Rail Research and Innovation Network (UKRRIN), which David Clarke described in his presentation at the opening ceremony. UKRRIN will initially bring together existing university and industry test facilities. The universities concerned have also submitted a bid for around £40 million to fund new innovation centres for digital rail systems and rolling stock, as well as a co-ordinating hub.

HAROLD will be part of the rolling stock innovations centre which will be led by a partnership of the Universities of Huddersfield and Newcastle. The intention is to create a network that will be open to all suppliers who wish to develop innovative products, with the hub providing a single point of contact and advice.

It is over 50 years since Harold Wilson delivered his “white heat of technology” speech in which he warned that, if the country was to prosper, a “new Britain” would need to be forged in the “white heat” of a “scientific revolution”. The rail industry’s drive for innovation is an example of how this sentiment remains true today, and it’s good to know that HAROLD is part of this.

Written by David Shirres.

Seamless interchangeability

Imagine Britain’s railways in 2040 and what can you see? Would we even call it a railway? When we’ve got autonomous pods to transport us from door to door, what’s the point of a railway? When we’ve superfast broadband everywhere, will any sort of travel be too expensive – a luxury for the planet to afford?

We railway engineers, and our operating colleagues, say the network is capacity-constrained, but anyone looking at the tracks can see they’re mostly empty most of the time…

Great openers for a chat in the pub with your mates – if they’re so inclined. But also serious questions not only for the UK but for the world. The more we grapple with climate change – represented by one of those four Cs that underpin our Railway Technical Strategy (namely Carbon; alongside Capacity, Cost, and of course the Customer).

The RSSB Innovation Programme sought and funded projects to develop ideas for ‘Radical Trains’ in a competition which has now come to fruition. Seamless Interchangeability is one of the fruits borne, quantifying significant benefit from a radical approach, not just to trains, but also to running a railway. New high-speed railways are being progressed, but what could we achieve on the conventional infrastructure – and what more could ultimately be achieved on high-speed lines, maximising overall network utilisation?

Dynamic coupling

Interfleet (now SNC-Lavalin Rail & Transit) and colleagues from Academia posed themselves the question of how to increase capacity further, taking the European Train Control System (ETCS) Level 3 – automatic train control – as a start point. We know closer running is already being considered, but how much more network capacity would we gain from actually joining trains together – coupling up (and uncoupling) – on the move?

For example, a long train composed of individual trainsets or vehicles might depart from a high-density London hub, and split en route with smaller trainsets breaking off from the rear to serve regional stations, whilst the front portion continues non-stop to, say, Edinburgh.

Dynamic coupling would also work in reverse, allowing passengers to travel from a regional station such as Hull, Lincoln or Oakham with their carriages being speeded up ahead, and then joined to the front, of a non-stop train en route.

“There’s no such thing as a new idea” goes the adage and, as those who know their history will assert, the rear- uncoupling process re-invents slip-coaching (but safely – with a controlled, independently-braked train). Front- coupling is, however, without precedent and trickier, but a credible build on ETCS Level 3 – the project’s starting point. ETCS would control trains until the minimum conventional safe separation, then train-to-train communications would supervise at distances smaller than relative braking distances. An alternative (to be designed) system would then switch in to manage the trains down to a maximum closing speed of say five km/h until they couple: conceptually similar to the quasi-static case of coupling two units at a platform.

Instead of changing trains, for journeys to and from regional stations, passengers could walk backwards down the same train. Conceptually, it should be physically easier and psychologically less stressful to walk along a specially designed train corridor to the correct carriage for one’s destination rather than the current process (of having to alight from a train at an intermediate station, find the platform for the next train and board it).

“But, thinking of the UK demographic where half the population will be ‘old’ in 30 years time, what about the elderly and infirm?” asked retired Railway Industry Association technical director Richard Gostling at a Rail Research UK Association (RRUKA) conference. Under Seamless Interchangeability, changing destinations on board the same train should be easier for all passengers – including people who are mobility impaired – than conventional changing at stations. We will certainly need to re-think train interiors and what they’re for – partly for seating, from where passengers can access catering, entertainment and other facilities; and partly as a transfer corridor which passengers use to reach their destination carriage, maybe including a travellator, or something resembling a stairlift, to ride on.

So, Seamless Interchangeability is a radically new operational concept enabling latent capacity to be freed up on the rail network (filling some of that fresh air over the tracks with vehicles), whilst at the same time increasing connectivity and hence customer satisfaction (increasing the number of through journeys to different destinations). Long trains running non-stop would need less energy to stop and start (consuming less carbon) and – in addition to fuel savings – a smaller number of more-efficiently utilised carriages would reduce leasing and maintenance costs.

But would it be worth doing?

Starting not only from the assumption of ETCS Level 3 Automatic train control, but also assuming that it would be technically feasible to design, build and approve suitable rolling stock and safe enough operating principles, what would the benefit of Seamless Interchangeability be?

“We wanted to quantify whether Seamless Interchangeability would make much difference – to establish whether it would even be worth thinking about designing trains and creating new operational rules to deliver the concept,” explained Ian Mylroi, principal consultant at SNC-Lavalin Rail & Transit.

The team persuaded RSSB to fund the research. A software model was built, based on key features of the Midland main line (MML), in Matlab – with Simulink, State-flow and dedicated C-code. The simulation consists of three layers: infrastructure and topology; interlocking safety control; and dynamic train movement.

SNC-Lavalin provided expertise (in human factors, railway control systems and operations, in addition to its business consulting, vehicle and infrastructure engineering teams); as did a specially composed advisory group – including representatives from a train operator (First Group), an infrastructure manager (Network Rail), a train builder (Siemens), and another university (Loughborough).

The combined team came up with parameters for the model, thinking hard about what assumptions were valid to maintain (such as timetabled station dwell) and which were unnecessarily constraining, in order that the true benefits of the Seamless Interchangeability concept could be explored. Sensible simplifications were made, including that individual vehicles had the same traction and braking capability (whether operating independently or coupled together to make a trainset of up to 11 vehicles), as well as the same physical characteristics (23-metre length, 43 tonne unladen mass, 7.5 per cent additional mass due to rotational inertia), and each person weighed 80kg with 10kg luggage.

Similarly, the route model considered representative nominal gradient topology with maximum speeds for each track section based on curvature and junctions, but assumed double-track throughout with four platform tracks at all stations, and ignored power loss over neutral sections.

The model recognises that other technologies will have advanced by 2040, so assumptions are made to ensure that the additional benefits that Seamless Interchangeability would bring are conservatively assessed. For example, regenerative braking is assumed by then to deliver double today’s best of 30 per cent conversion rate from kinetic energy back into traction power. By thus overstating the likely regeneration improvement in 2040, we understate the significant carbon benefit of the Seamless Interchangeability pattern of reduced stopping and starting of long through-trains.

The model provides a baseline against which other scenarios can be tested and developed, using the software’s graphical user interface to vary parameters. It is not a perfect replica of the detailed features and absolute values of current MML operations, but the model is sufficiently realistic that changes in Key Performance Indicators found under the different scenarios tested are real: and they show significant benefits.

What would we gain?

The main target was to enhance network capacity, but the team found that Seamless Interchangeability actually offers improvements on all four Cs of the Rail Technical Strategy.

Simpler journeys with fewer changes would increase customer satisfaction (although this benefit was not quantified); fewer stops for through services – and more efficient vehicle utilisation – would halve the miles run overall, cutting maintenance and traction energy costs and reducing carbon accordingly.

Fewer stops would also enable more efficient use of the network, doubling capacity by creating more paths to run trains and by reducing journey times, further enhancing customer benefits.

Despite the system deploying fewer vehicles than currently, potential disbenefits from doubling passenger loading were not seen: load factors remained below 90 per cent in all scenarios, albeit noting the simplifications made – such as to assume that all rolling stock had exclusively standard class accommodation. A negative consequence of the overall optimisation and aggregate reduction in journey times was that a few journeys would take longer, such as those to small regional stations adjacent to significant hubs which are currently served infrequently, but directly, by intercity-style trains.

Could it be implemented?

Technically, implementation of Seamless Interchangeability on the railway would require a paradigm shift in rail operations and rail travel. Implementation requirements have been developed and worked up to give indicative costing for four key system elements: signalling, vehicles, operations and infrastructure.

Signalling for Seamless Interchangeability is a logical extension of the current cross-industry work towards ETCS implementation and could progress at marginal cost to that massive overall project. Vehicles will need significant modification to trainsets at the front and rear to enable dynamic coupling, and to interiors so as to facilitate passenger transfer to the correct portion of the train. The project concludes that research would be worth initiating, such as to revisit crashworthiness criteria given signalling system robustness and further potential for modal shift onto railways from less safe, less carbon- friendly modes. Interestingly, the biggest changes needed may be to the infrastructure, particularly station layouts which may require significant investment, and possibly more land-take, to deliver the Seamless Interchangeability concept.

So where are we going?

Perhaps, returning to the initial Radical Train idea, people in 30-odd years time will leave their homes in automated driverless pods to travel to stations where they dock into trains which couple dynamically through Seamless Interchangeability into longer trains. Then they’ll move down the train to their destination vehicle and subsequently slip off from the combined running into individual pods again to reach their destination doorstep.

Operational rules would need to be developed to support each stage of implementation, building on a fresh look at overall system safety and how people could best use Britain’s railways. Initial modelling found that, compared to the vehicle and operational challenges, infrastructure and system investment costs were low, readily traded off against reductions in fleet size (and therefore reduced vehicle leasing and maintenance costs), and lower traction power costs. Refining these cost estimates is a key area for future work.

The world moves on. Since the Seamless Interchangeability project described here was conceived, RSSB has developed a project known as Closer Running under the cross-industry FuTRO (Future Traffic Regulation Optimisation) Board. FuTRO aims to identify technologies to support a vision of the rail industry in 2040: technologies which optimise traffic management, increase network capacity, reduce energy consumption, hasten service disruption recovery, and improve customer communications and satisfaction. Seamless Interchangeability logically meshes with FuTRO’s closer- running research programme going forward.

Seamless Interchangeability is no quick fix to rail capacity, but the project has established that it’s worth pursuing. Proposed next steps are to focus on a particular route to consolidate understanding of the benefits – and costs – of adopting the novel approach, prior to devising a network-wide implementation plan.

Clive Burrows, group engineering director of First Group and chair of the FuTRO Board, said: “You have uncovered the results we hoped for, and a lot more besides. The question is how best to address the challenges to Seamless Interchangeability so we can begin to design and evolve the technologies and the thinking to deliver an optimal future railway.”

Written by Rebeka Selick, who was formerly head of research at SNC- Lavalin Rail & Transit and is now head of rail at TRL. Thanks to SNC-Lavalin Rail & Transit, RSSB, Siemens, Network Rail, First Group and Loughborough University for their help in preparing this article.

125mph S&C handback – a UK first

At the beginning of the year, the Rail Engineer magazine (issue 136, February 2016) covered the Christmas and New Year programme of track delivery work, including a plain line possession on LNE that was proudly handed back at 125mph. At the time we mulled over the possibility that 125mph handbacks for switches and crossings (S&C) projects could be just a couple of years away.

Nine months later, and two years after the S&C North Alliance – the powerhouse partnership between AmeySersa and Network Rail – was formed, we’re celebrating the delivery of Britain’s first ever 125mph handback on an S&C project.

The expectation of higher handback speeds is becoming the norm, especially on busy passenger routes where the timetable is sensitive to train speed reductions. However, grasping those extra few mph (or km/h) takes a great deal of extra care. 25mph on top of 100mph may not seem much, but anyone involved in managing the dynamics of a train going at 125mph will appreciate just how fast things are happening.

On plain line, 125mph is relatively straightforward. High speed running over switches and crossings is another kettle of fish. To open an S&C renewal at 125mph takes careful planning. Many in the industry thought that this milestone would be years down the line.

The complications

Pway engineers can look away now while we go through the basic list of the fishes in the kettle. Pretty obviously there are the switches, which have to maintain their integrity and relative positions with the stock rails. There is a crossing which in itself could involve moving parts to avoid there being a gap to jump over. There is an assortment of bearer lengths, and the whole lot has to be tamped using a specialist S&C tamper. Oh and then there’s the signalling and OLE to contend with. So, S&C isn’t straightforward.

Nick Matthews is the programme engineering manager with the S&C North Alliance, and he explained what it takes. “You’re looking at the culmination of two years of work – we’ve taken a gradual approach to what is a major step change in S&C delivery. We’ve been quite cautious, by identifying the right test sites, techniques and applying the due diligence to succeed.”

Nick refers to “progressive assurance”. It means looking at each stage in a project and making sure that it is demonstrably checked against defined tolerances.

With each stage signed off as being within tolerance, the Authorised Person – the individual who has the responsibility at the end of the possession to decide on an opening speed – will have a complete history of each stage in the works.

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The issues that are critical to successful high-speed track handover at the end of a possession are largely hidden from view, buried in the ballast. Top and line may appear fine, but it is the quality of formation treatment and ballast compaction that will decide whether a train rides smoothly over newly laid track or whether it – or subsequent trains – experiences rough riding (or worse).

Compaction tracked

The S&C at Belford, on the East Coast main line (ECML) north of Newcastle, was chosen as the site to go live with progressive assurance. Between 16 and 19 September 2016, there were two worksites involved on the Down line at each end of the Down passenger loop – 506 points (facing) and, about a mile further north, 510B points (trailing). The latter set of points was planned for a 125mph handback. 506 points, being a facing connection and also close to Belford level crossing, was planned for 80mph.

Both sites were dug to 400mm and made good with a 100mm sand blanket followed by 300mm of bottom ballast compacted in one layer by a Variomatic Bomag roller. This particular machine gives an output trace of its performance and the stiffness of compaction achieved at every stage, which is retained as part of the assurance process.

At the ends of each excavation there is a transition length where the depth of dig tapers up to the existing bottom ballast level. A basic formula of line speed divided by seven gives the appropriate gradient. The purpose of the transition is to ensure that trains don’t ‘drop’ abruptly into a hole of relatively less compacted ballast and at the other end don’t suddenly hit a step. Although the possible differences in level are very small, trains travelling at high speed are likely to experience a rough ride.

The S&C modular units were then installed and aligned manually to within 5mm. Then followed the stone drop followed by a combined tamp/DTS (dynamic track stabilisation). The first pass is what is termed a disruption pass where every single bearer, including any hollow bearers, is tamped with the DTS following on in maximum mode to give maximum ballast consolidation. There’s then a second, very fine lining pass with the tamper, with the DTS in variable mode. Rather than giving maximum consolidation, it follows the geometry ramping up its action where slight track tolerance issues are found.

 

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DTS reputation

It may be worth reflecting for a moment on the DTS function. DTS machines (right) have been around for several decades. Indeed they formed the backbone of the high- speed handbacks of the 1980s. For our non-pway readers, DTS machines simulate the passage of trains by vibrating the track – a lot. But they had their detractors. They were perceived as being…brutal.

Whether this was a valid viewpoint could be up for debate. For track compaction they were doubtless very effective – because they were indeed brutal (allegedly). For lineside structures and buildings they were quite rough. They made the teacups rattle. For S&T equipment they were – or at least it was felt that they could be – downright destructive. For many, the perception persists to this day, and so it was necessary to be a little more scientific to measure what they are capable of doing – and undoing.

In our last article on this subject we referred to forthcoming trials to assess the true nature of the DTS beast. These were to be conducted through Network Rail’s central innovation team of IP Track with help from Southampton University – their ISVR Consulting.

Two sets of switches were chosen, located in Grange sidings near Stoke. The trial was run in February and June of this year. A 39-page report, with many tables and graphs, concluded that an appropriately used DTS should not cause any more vibrations than would be experienced in normal train running. However, the S&T equipment at Belford was taken off just in case…

And the first train is…?

When the time came for the Authorised Person to assess the track at Belford, he was in possession of a complete file of all the stages in the relaying process and their measured results. Progressive assurance proved its worth. Along with what could be seen and, just as importantly, a fact-based knowledge of what could not be seen, the temporary speed boards were ‘spated’ – that is, a cancelling indicator was shown.

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Despite the months of planning, it isn’t possible to anticipate what the first train to run over the relaying site will be. In the end, a freight train running at its speed of 60mph turned up. The site team didn’t have long to wait, though, for an empty coaching stock movement of an HST from Heaton Depot to Berwick, which duly rattled through with its throttle wide open for the clear line ahead. A very satisfying end to a well-planned endeavour.

Next up?

What’s next then? Whilst opening at line speed won’t be appropriate everywhere, making high speed handback BAU (business as usual) on S&C is realistically on the cards – it’s simply a matter of putting the pieces together – combining the people, techniques and technology to deliver more of the incremental improvements we’ve seen over the last few years.

The next big challenge will be to tackle the logistics of relaying a full crossover. For our non-pway readers, the complication here involves bearers that are long – very long. They are continuous under both tracks. Anything you do to one track affects the other whereas, with the single leads at Belford, none of the timbers extended under the adjacent track and the connection to the loop line was a modest 40mph. Nick acknowledges that opening a full crossover at 125mph will be challenging, but having tested the concept of progressive assurance and found it to be fit for purpose, there’s just the engineering to sort out.

And engineering’s easy, isn’t it?

Written by Grahame Taylor

Rail Engineer Issue 145: November 2016

RVE goes from strength to strength

Writing about the 2015 RVE exhibition in Rail Engineer (issue 133, November 2015), Nigel Wordsworth called it “the best yet”. I was there last year too, and this year was even better. Coming just two weeks after the huge InnoTrans exhibition (where I kept getting lost!), it clearly illustrated the value of a “smaller, but perfectly formed” exhibition. It did exactly what it said on the tin, bringing together, under one roof, many of the suppliers who can help enhance rail vehicles.

Held at Derby’s Riverside Centre, just across the way from Derby County’s football ground, it was organised by Onyxrail, whose managing director, Kevin Lane, is someone I first worked with when he was at Metro Cammell 30 years ago!

There was a large area for exhibitors with space to chat. A series of lectures were given in an adjacent room, once again presided over by journalist Ian Walmsley, whose often controversial views are published elsewhere. His keynote is an annual treat; always up to date and relevant, but delivered with a wicked sense of humour.

Ian gave a very important message about how the industry has changed in just a year. Last year, there was a lot of confidence that the way forward was to be life extension of mid-life rail vehicles with enhanced performance and passenger amenity to deliver the service customers would want. What actually happened is that the quality requirement in recent franchise competitions has led to the successful bidders buying new trains. As a result, even some quite recent trains will shortly be replaced. No doubt these trains will cascade to other operators, opening opportunities for refreshment, refurbishment and technical uplifts.

From the proliferation of innovative and relevant exhibitors, it was clear that requirements are changing in the rail vehicle enhancements business. When I was involved in the work – indeed helped to create the industry with the London Underground refurbishments in the 1990s – enhancements were typically just to electrical systems and fixtures and fittings. In the modern railway, electronics, networks, 4G, Wi-Fi and information systems have become a very significant part of the work and were heavily represented alongside the more traditional suppliers of labour, interior fittings and seats.

Perhaps future exhibitions will see suppliers are competing to fit ETCS equipment on existing trains. Who knows?

To avoid this being a travelogue of the exhibition, I’ll refer readers to the RVE website and concentrate on the exhibitors that caught my eye.

Information systems

Infodev was showing its real time passenger counting system. I spoke to Pierre Deslauriers, the company’s CEO, and discussed the accuracy of his system, having been highly skeptical about such devices in the past. He explained that, generally, his company recommends to customers that they do a trial and monitor the sensors using video cameras to confirm for themselves that 99% accuracy – Infodev’s claim – can be achieved. Needless to say he has many satisfied customers. Having counted people on and off, the information can be used both to inform customers how busy the train is and to build very accurate data for the operator on how its services are used. This can be used in making tactical control decisions as well as for the strategic planning of services. Pierre told me that the latest application is on Scotrail where the installation is being carried out by partners Onyxrail.

I moved on to Televic Rail, whose elaborate stand of passenger information displays included the wide-screen unit seen on the latest Siemens Class 700 and 707 EMUs. Also amongst the displays were the neat little seat reservation indicators which will be used on the Intercity Express trains. Compared with previous electronic reservation displays, these looked much more eye catching.

Whilst the displays are the primary product of the company, the value to train operators is provided by Televic’s LiveCom system, which allows them to generate or edit content and, using iSync hardware and software, to send that information directly to the train or trains concerned. Thus the displayed information is no longer limited to what has been loaded onto the system in the depot. iSync can also be added to existing trains to facilitate the export of data from on-train systems to a centralised server.

Next was Diagnostyx – a partnership of Arrowvale, SNC-Lavalin and Clyx.net which provides an on-train data logger, transmission facilities, engineering, installation, application support, and cloud data hosting.

These systems will deliver benefit if information can be distributed or collected via a network. More and more legacy fleets are being equipped with Ethernet networks which can, for example, distribute passenger information, and provide customer Wi-Fi. There is also the possibility of connecting any suitably equipped systems, such as the on-train monitor recorder, for remote downloads.

Various electronic elements – often literally black boxes – were on show, including switches, routers, Wi-Fi access points and 3G/4G interfaces that provide the function of the network. Suppliers demonstrating this kit included Comtrol and Westermo.

Ciesse introduced its RailWare EcoS system, an energy monitoring system that works in real time to the latest European standards. Designed to interface with other systems, it can be used to provide drivers with information about energy consumption. Since it monitors voltage in high resolution, it also gives an indication of pantograph performance. Once data is downloaded, it can be analysed in a variety of ways, for example, to identify different driving styles.

I met Alan Stewart from Perpetuum, whose product is most usually employed to monitor axlebox vibrations powered by energy harvested from the vibrations themselves. The tiny amount of power generated, approximately 80mW, is sufficient to operate a small circuit that records the output of a triaxial accelerometer and send this information wirelessly to a train mounted data accumulator. This information, together with other data such as train position, is sent back to base where it can be used to identify issues with wheel bearings, wheels themselves and also the track condition. Each time I speak to Perpetuum, they have something new to talk about, most recently the ability to detect wheel flats and a forthcoming development of their bearing sensor.

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Other highlights

Dellner had an automatic coupler on display. I am used to the relatively simple London Underground Wedglock automatic-coupler, and I found it instructive to learn how complex a modern auto coupler can be; an electro- mechanical device which has to survive in possibly the most exposed location on the train. For Dellner, just getting its demonstrator into the hall was a challenge as it weighs about 500kg!

Whilst I found out a lot about how a coupler works, the purpose of the display was to demonstrate the benefit of retrofitting existing couplers with heating elements to ensure that they don’t freeze in winter and to help keep the electrical contacts dry. It was very impressive to feel by touch and to see by thermal image camera how quickly the heating elements work.

I recalled trials of aromas on the East London line of the Underground in the 1990s that received much derision from the press. I hadn’t imagined that aromas had reappeared until I walked up to the Signature Aromas stand (Kevin said they’re not to be sniffed at – groan!) and realised that I was familiar with the smells, indicating that a number of operators are using those products to improve the customer ambience.

Apparently, one operator changes the aroma depending on the season and, of course, they have a ready use to counteract the less pleasant smells in toilets! Who wants to be on a smelly train when you can be wafted to paradise with the fragrance of jasmine?

Trolex had on display some LED lamps in the format of fluorescent tubes, with all the electronic components inside to allow them to be fed from 24V or 110V DC. Whilst there is still a cost premium for LED over conventional lamps, it is my view that it would be madness not to use LED lamps throughout for new trains, and there is a good case for retrofit on existing trains despite both the higher cost of the lamps and a one-off cost to remove existing fluorescent lamp control gear. Apart from the reduced maintenance required by LED lamps, the reduction in energy consumption can produce environmental benefits or, in some cases, reduce the load on supplies with marginal capacity to provide headroom for new systems such as Passenger Information Systems or Ethernet networks.

Strukton Rolling Stock was displaying its power converter modules and a three-phase drive module for use in a shunting locomotive. The approach is to configure standard circuit designs to meet the individual customer’s needs. One example is the DC:DC chopper provided for the Vivarail conversion of the former London Underground District line trains to diesel-electric operation.

So far, I haven’t talked about the traditional suppliers to rail vehicle enhancement projects, such as interiors, seats and upholstery. I bumped into Keith Griffiths, who I worked with on the Victoria line 1967 stock refurbishment over 25 years ago. He is with the I M Kelly Group which was showing off both its own train driver’s seat and the LEAN2C passenger seats from Fisa in Italy. The aim of this seat was to look and feel comfortable whilst providing a recess in the seat back to accommodate the knees of the passenger sitting behind. The recess also allows the seat to meet all the UK structural requirements whilst being lightweight.

McAuley from Northern Ireland supply interiors and grab poles internationally. Getting lightweight grab poles to meet all the structural requirements, applying hard wearing finishes and compliance with the TSI for People of Reduced Mobility or the Rail Vehicle Accessibility Regulations, is far from trivial. Moreover, as trains get more crowded, there tend to be more handrails as everyone must have something to hang on to!

Muirhead high performance leather had a very simple stand; bar chairs upon which an array of leather swatches were spread. I thought this was incredibly effective, as it is the colours and feel of the material that sells it.

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One must not forget the suppliers who carry out the engineering, installation and homologation of the various enhancements. These included:

  • Onyxrail, the show organiser, is also a turnkey installer of technical modifications and partner company Skills4Rail provide skilled labour for depot based modifications.
  • Wabtec, one of the sponsors, is now a multinational supplier of parts, equipment and subsystems as well as owning four sites in the UK for vehicle and component overhaul and enhancements. These are in Kilmarnock, Doncaster, the former Brush works in Loughborough and the LH site in Burton upon Trent.
  • Knorr Bremse Rail Services has made great progress in vehicle enhancements since taking over the former Railcare site in Wolverton, Milton Keynes a few years ago.

Providing exceptional added value to visitors were presentations from representatives of the Department for Business, Energy and Industrial Strategy; Wabtec; Ciesse; Ricardo Rail, Rail and Road Protec; York EMC; Eversholt and Hitachi, covering subjects as diverse as the opportunities to improve fleet performance though to the performance of ETCS equipment on class 37 locomotives.

As the show organiser, Kevin Lane was very excited about this year’s show. He said that he is consistently surprised and encouraged by its growth in terms of the breadth of products and the calibre of the companies that choose to exhibit at RVE. He added that the forum which runs alongside has offered some excellent technical papers that provide an informative view on the opportunities available to train operators and train owners.

It was clear that Kevin is ambitious for the future. He said: “2016 marks a major phase of development for the show and our intention is to double the size of the show for 2017.” He was full of praise for the support of Wabtec Group as sponsors, the help provided by of the Department for International Trade, the loyalty of the Rail Alliance to the show and media partner Rail Media. Their support underpins RVE as the show for those seeking the best railway products and services that the supply chain can offer.

So RVE 2016 is over, and organisation has already started for 2017. It’s planned to take place on Thursday 5 October 2017 at a new venue, the Derby Velodrome. See you there.

For more information on RVE2016 and RVE2017, visit www.railve.com.

Written by Malcolm Dobell

High-speed rail technologies

The Institution of Mechanical Engineers frequently organises topical seminars with excellent speakers. This one was no exception with speakers such as Jim Steer and Andrew McNaughton. The timing of the event was to celebrate the success of the UK’s High Speed Train (HST), which has been responsible for transforming the image of inter-city rail travel since it entered service on 4 October 1976. It was the 08:05 London Paddington to Bristol Temple Meads, although one member of the audience was on what he was told was the first train which departed from Weston Super Mare. Perhaps there was a first “up” and a first “down” train?

As Andrew Mellors, deputy managing director and engineering director of GWR said, as he introduced the event, the purpose was not to rake over the history of the HST, more to nod to its history whilst looking forward at the technologies that are required for today’s and tomorrow’s high speed lines.

Yesterday

The first presentation was by another Andrew – Andrew McLean, the head curator at the National Rail Museum in York. His title of “The Most Successful Train in the World?” referred to the impact of the HST. His assertion was that the UK has always been in the forefront of high-speed railways ever since Stephenson’s Rocket travelled at the unheard of speed of 30mph, and that the times when the UK appeared to be in the speed wilderness were mere blips of history.

Andrew treated the audience to a gallop through railway development in the nineteenth century before going on to the era between the two World Wars, immediately following the formation of the “big four” railway companies. He focussed particularly on the London and North Eastern Railway and its chief mechanical engineer (later Sir) Nigel Gresley, who pushed the envelope to and beyond 100mph.

Gresley was a man who travelled widely and had befriended Ettore Bugatti, from whom he learned the importance of streamlining. He applied these ideas to the A4 pacific locomotives, but also to the rest of the train with articulated coaches where the gaps between coaches with ‘India-rubber fairings’, and a streamlined observation car minimised turbulence following the train.

Andrew also emphasised the importance of LNER’s publicity and service that accompanied the streamlined trains, with the train as the very visible and marketable ‘face’ for the offering.

The second World War and nationalisation almost certainly extended the life of steam in the UK by about 20 years, and the story moves to the 1960s where there was both an urgent need to do something about the competitiveness of long distance rail and to solve some fundamental problems of keeping trains on the track at higher speed. Andrew mentioned three people who were transformational in UK railways and had influence worldwide.

Dr Alan Wickens led the research work to understand why high speed trains were prone to derail and to provide solutions, leading directly to the work on the Advanced Passenger Train.

Terry Miller, then chief mechanical engineer of British Railways, led the development of the HST and the strong, light and spacious Mark 3 carriage; and Kenneth Grange designed the iconic and timeless “face” of the HST. Andrew argued that these three men had a transformational impact on the UK’s long distance passenger services. Together with the Deltics on the East Coast, and the ‘sparks effect’ on the West Coast main lines, BR had products that could be marketed well, and developed the ‘Inter-City’ brand, with the HST and Mark 3 coach featuring strongly in advertising. The HST still holds the world speed record for a diesel train of 148mph, recorded in 1987.

Andrew concluded that the HST has had a transformational impact on the UK economy (for example, people now commute to London from York) and is going to continue in front line inter-city service in Scotland until the end of the 2020s, still retaining the timeless good looks designed by Kenneth Grange all those years ago.

Today and tomorrow

The keynote address was given by Karen Boswell OBE, managing director of Hitachi Rail Europe. Her message was that high speed has been good for Britain. Moving on from the success of the HST, she talked about the contribution of the class 395 trains to the economy of Kent, how these trains have halved the journey time to Ashford and that the domestic high speed service carries half the passengers that use the High Speed 1 route.

The success of this fleet has established Hitachi’s reputation in the UK and has led to the orders for high- speed trains for East Coast, Great Western Railway and Trans Pennine Express as well as inter-regional trains for the Edinburgh-Glasgow route.

Karen’s message emphasised connectivity, creativity, collaboration, and engagement with people at all levels, whether customers or employees. Moreover, she highlighted that high-speed lines are successful the world over. Don’t let critics talk HS2 down, she said.

Practical lessons of high speed

Jim Steer, who set up Steer Davies and Gleave in 1978 and has been a champion of high speed rail for over three decades, talked about what can be learned from 125mph operation in the UK, from High Speed 1 and from the experience of France.

Jim highlighted that, as 125mph operation spread through the UK, journey times fell, stimulating more journeys and land development. Many of these improvements took place at roughly the same time as other developments including motorways, housing and retail. As such, it was not easy to attribute which activity contributed most to the economy. Complicating the picture is the green belt land around most of the UK’s major cities, which means that development might not necessarily be allowed to happen. He cited examples of Doncaster and Newport, which received high speed trains but did not receive significant economic development.

Photo: shutterstock.com
Photo: Paul J Martin/shutterstock.com

For his section on HS1, and with reference to the fears of many of HS2’s neighbours, Jim recalled that the Eurostar train is comparatively noisy and that it was the subject of many complaints when running over the old boat train route on the Southern electric network. These complaints ceased when HS1 opened. His point is that a well-designed high-speed railway is generally not intrusive on neighbours’ lives. The key points included:

  • HS1 has stimulated development around Kings Cross/ St Pancras whilst Ebbsfleet has yet to catch up;
  • HS1 was justified on forecast Eurostar numbers that have never been forthcoming although the introduction of the domestic high-speed service has delivered, overall, passenger numbers in line with forecasts;
  • Reliability of the HS1 infrastructure is very high;
  • Infrastructure needs to be flexible and this flexibility has value for uses not envisaged when the line was built, such as the HS1 domestic service.

France

With its main cities tending to be separated by significant distances, France was an ideal location to grow high-speed rail. For example, the first high-speed line, from Paris to Lyon, currently runs trains in just two hours. By comparison, a car journey takes four hours and, unless you are close to either airport, flying is slower than the train.

The success of the high-speed lines is well known; France is currently constructing four more lines, and the risks and rewards have become well enough understood to make a Public Private Partnership viable. Jim also highlighted that countries which have commenced building high speed lines have always built more of them.

He added though, that a number of lessons have been learned. France expanded TGV services but has recognised that secondary routes have been neglected. Furthermore. the president of SNCF has declared that railways are guilty of underestimating long term growth, that more cross-Paris travel routes should have been provided and that strategic thinking should be applied to linking every major town and city, and not just be Paris- centric.

In closing, Jim Steer made several points. Mixed traffic railways are not efficient users of capacity, and taking long-distance fast journeys off existing lines provides the opportunity to improve the offering on those existing lines.

The HS2 business case assumes best-case growth of about 2.8 per cent, although current actual growth is significantly greater than the HS2 best case.

And the key to the success of high-speed lines is improved connectivity, both for customers and for regional economies.

What Can the UK learn from Japan?

Felix Schmid, director of education at the Centre for Railway Research and Education at Birmingham University, compared the European and Japanese approaches to high-speed rail or, as he asked, “Is it all about speed?”

Starting with a little self-deprecation, Felix told his audience: “I visited Japan thanks to Central Japan Railways’ exchange programme. I had read lots about Japan, about its railways and the Shinkansen and I was convinced that I would learn nothing new! And then I understood…”

Felix highlighted the essential truisms of high-speed rail everywhere – bringing communities closer together – and contrasted some of the engineering approaches in Britain and in Europe with those adopted in Japan. He illustrated how the Shinkasen developed on Honshu island, which is slightly smaller than Britain but has nearly twice the population.

More significantly, the Tokyo – Osaka corridor (about 500km apart) represents less than 25 per cent of Japan’s land mass, but has nearly 60 per cent of the population and more than 60 per cent of Japan’s economic activity. It was between these two cities that the Tokaido Shinkasen opened in 1964, partly to reduce journey times and partly to improve capacity.

The opportunity to increase services on Japan’s conventional 1067mm gauge mixed traffic lines was small. The Japanese decided to create the new line using standard gauge, dedicated solely to the high-speed service, thus not importing any of the issues that might affect the narrow-gauge lines. From opening, the reliability of the service has been legendary, with average delays of less than six seconds per train.

In covering the expansion of the network, Felix superimposed the network onto a light pollution map showing the distribution of Japan’s urban population, and how, in the interests of connectivity, both dense and lightly populated areas are served.

Felix moved onto railway system design, where there are some differences in approach between Europe and Japan. As the Shinkansen has always been a dedicated system, Japan has developed its infrastructure based on the needs of the train. For example, the Japanese engineers determined that a width of almost 3.4 metres was required to accommodate rows of 3+2 seats in standard class. This determined the structure gauge and track spacing.

Photo: Shutterstock.com
Photo: shutterstock.com

However, in the desire to build stations in densely populated areas, where people want to go, land take had to be kept to a minimum. It became usual, therefore, to specify quite short turnouts with an operating speed of 75km/h. For these not to be a constraint, trains with high acceleration and braking rates were specified.

Conversely, in Europe, it is quite common for high-speed trains to have their own infrastructure and also to use the existing infrastructure at ends of the line, sometimes for a considerable distance. Thus, the vehicle gauge has to be compatible with the existing lines, which is almost always smaller than in Japan.

In Europe, space is often made available for longer, 230km/h turnouts from the main line to a deceleration track and then 95km/h into platforms, with the reverse for acceleration. These turnouts are rated at more or less the correct speeds for the deceleration (and acceleration) curve of the trains, and thus a stopping train will get out of the way of a following train with minimal impediment. The higher the throughput required, the more important this becomes, particularly if the stopping pattern is irregular.

However, 230km/h turnouts are very long and require considerable track equipment to make them work, resulting in issues for maintenance and reliability.

Felix’s point was that the high-power train and simpler infrastructure provided a number of benefits such as:

  • High ratio of motored axles increases acceleration andbraking rates – the latest Japanese trains have all axlesmotored;
  • All axles motored opens the way for purely electro-dynamic braking (270km/h to 30km/h);
  • Low speed (75km/h) turnouts have multiple benefits:» No need for swing nose crossings / moving frogs;
  • Low complexity and cheaper to buy and renew;
  • Reduced land take and lower track forces;
  • Replacement in one five-hour maintenance window.
  • Low technology maintenance is flexible.

Felix also stated that all aspects of a journey need to be considered in the planning of high-speed lines. His example was a three-hour journey where only 90 minutes are on the train. If a high-speed line allows the on-train time to be reduced to 60 minutes, the saving in on-train time is one-third but the saving on the overall journey is only one-sixth.All phases of a journey, both value-adding and non- value-adding, need to be considered. Non-value-adding elements include having to wait 10 minutes to buy a ticket or walking up and down the train to find a seat.

He also illustrated the sort of analysis that can be undertaken to minimise the activities necessary at terminus stations (other than disembarking and embarking passengers). He compared this with what the low cost airlines have done to minimise time on stand at airports.

Developments in high-speed rail

Andrew McNaughton, technical director HS2, has over 40 years in the industry or, as he put it “40 years of mistakes and they call it wisdom”. Andrew’s approach was to emphasise similarities, not differences, because, he said in his understated way, “the laws of physics are pretty much the same worldwide”.

High-speed rail is over 50 years old, has been adopted across the world and has all been built to similar technical standards. Andrew illustrated the point with a photograph taken in Korea of a train to largely French standards on track to largely German standards.

Highlighting some different approaches to optimising requirements that can possibly be conflicting, such as connectivity, capacity, reliability and availability, Andrew described how there are broadly three categories of high- speed lines in different countries/continents.

In Asia, closed systems are preferred, with high-speed trains running solely on dedicated infrastructure. This tends to produce the highest capacity and reliability.

France, Italy, and the UK have generally adopted high- speed infrastructure where only high-speed trains run, but some of those continue on existing ‘classic’ lines to destinations beyond the high-speed network. There is generally high capacity on the high-speed line.

Germany, Austria and Switzerland have built new high- speed lines that allow mixed high speed, conventional and even freight trains to operate to destination on existing lines. These tend to have lower capacity reflecting limited demand.

Andrew talked about the discipline and opportunities offered by closed systems which are similar to those of a metro – managing all aspects of the operation to maximise capacity. The issue of demand is critical, there’s no point building the railway if the demand isn’t there. Moreover, if there is demand for a new railway, then it might as well be build it as a high-speed one – the additional cost is comparatively small and the benefits are significant.

Moving onto HS2, Andrew reiterated that HS2 is all about capacity. Britain is growing. In 2008 the population of England was about 52 million, by 2033 it’s estimated to rise to 60 million and to 70 million by 2050. He illustrated the UK with a light-pollution map and superimposed the path of the Y-shaped HS2 line to illustrate that it is planned for HS2 to go where the people are located.

Photo: shutterstock.com
Photo: Muratart/shutterstock.com

Andrew outlined the operational specification for the core section:

  • Capacity: up to 18 services per hour each way of up to1,100 people per train, which represents roughly the capacity of three 3-lane motorways;
  • Availability: operational hours 05:00 to 24:00 (0:800 onSundays);
  • Reliability: average delay less than 30 seconds per service;
  • Journey times will be based on up to 360km/h maximum speed balanced with environmental impact;
  • Reduction of whole journey time – station design,service frequency will both be part of the mix.

He then moved on to infrastructure maintenance specification. Bluntly, he said infrastructure maintenance is still in the dark ages. Anyone running trains at speeds of 100m/s or more (360km/h) really ought to know on a continuous basis that it’s safe to do so and it should rarely, if ever, cause service-affecting delays. His outline maintenance specification is thus:

  • Automation of examination/condition monitoring;
  • Preventive servicing;
  • Mechanisation of maintenance (replace not repair);
  • Largely rail-based;
  • Standardised elements;
  • ‘Factory’ approach throughout.

Building on his comments about the whole journey, Andrew showed a number of cartoons that had been produced when interviewing potential customers on their wants and needs from the stations. The challenge for the designers is to provide for many thousands of individual journeys and all sorts of individual needs, but common factors emerge such as ‘no barriers’ and ‘no steps’.

Andrew foresaw that customers should be able to navigate the station to their train using satnav style spoken instructions though their smart phone, based solely on knowledge of their current location and their train time/seat number. Clearly there are a number of developments required to make all this happen, not least the ticketing system to enable ‘barrierless’ travel.

His team is already modelling the performance of the line as it is being designed using BIM (Building Information Modelling), which allows all elements to be integrated in a virtual world to ensure they all work together before anyone starts building anything.

Metro – a digital incubator for high-speed rail

Andrew Love and Doug Blanc of SNC-Lavalin argued the proposition that the integrated approach of modern metros provides a working model for closed system high- speed systems.

For example, metro CBTC systems do today what it is hoped the ETCS level 3 might do at some point in the future. However each supplier’s CBTC system is proprietary and the trains and infrastructure both have to have the same system.

It is also fair to say that few, if any, metro CBTC systems cope well with freight (engineers’ trains in metro-speak). Metros usually have the advantage of integrated management, ability to specify the whole system and have relatively small fleets/infrastructure compares with most main line railways. However, taking the system design principles and applying them to the HS situation is a valid proposition.

All in all, it was interesting to hear of the various developments, both in the UK and overseas. Whilst there were some differences of opinion, speakers generally agreed on the way forward. The only significant divergence of view was about the proposed station track layout and length of points, with Felix Schmid advocating the Japanese short points whereas HS2 is proposing something that takes up more space but is likely to have headway benefits.

Andrew McNaughton summed it up pretty well when he said, in response to a question, “Well, decisions have to be made”.

Written by Malcolm Dobell

Collaborating on the Red Arrow

The term “Jack of all trades, master of none” dates back to Elizabethan times, with one William Shakespeare being on the receiving end of an early version. Today’s railway industry is very complex technically. The supply chain is made up of many small companies, each with its own specialisation, and several giants who provide a broad range of services and products. To prevent them being “masters of none”, they employ a host of specialist engineers and technicians, masters in their own fields, and combine that knowledge and experience to provide a complete offering.

Even so, every company will still have its strengths and weaknesses. The latter may not necessarily be technical, but could be geographical or political.

On many occasions, the company’s strengths allow it to win supply contracts from its customers. However, there are occasions when the weaknesses might prevent that, or at least throw the result into doubt.

Pragmatic managers are therefore quite prepared to collaborate with other concerns whose own strengths and weaknesses counteract theirs. Joined in a collaboration or joint venture, the result should be almost only strengths, and very few weaknesses.

Planning for speed

This was the case when Italian state railways (Ferrovie dello Stato – FS) first started to consider a new very-high-speed train for its Eurostar Alta Velocità Frecciarossa (Eurostar high speed Red Arrow) services operating Turin-Milan-Florence- Rome-Naples. New lines from Milan to Bologna (opened 2008) and Bologna to Florence (2009) would then combine with the older Direttissima line (1977-1986), resulting in a high-speed corridor between Milan and Rome. Another new line (completed 2009) would take trains on to Naples.

To have a train design ready for the new route, Bombardier and AnsaldoBreda (now Hitachi Rail Italy) started working together in 2008. A design office was established by the joint venture at Bombardier’s Hennigsdorf plant, pulling together experts from various locations around Europe.

“It was not just Germans and Italians,” remembers Marco Sacchi, Hitachi Rail Italy’s head of engineering. “There were Spanish engineers from Trápaga, bogie designers from Derby and an electrical power team from Västerås in Sweden.”

Bombardier personnel were responsible for the concept and detailed design of the trains, the provision of propulsion equipment and bogies, as well as project management, engineering, testing, homologation and commissioning of the first five trains. AnsaldoBreda personnel were looking after the industrial design, carbody, interior, interior systems, doors and signalling, together with final assembly and commissioning of the series production trains. Both parties were involved in detail design and engineering activity.

“But everybody worked in one office,” adds Marco. “It was a strong team to develop the train. It was a very challenging time, the customer had big demands for both technical solutions and aesthetics.”

brand2

In terms of performance, the team was working to produce a train capable of 350km/h (217mph), even though the high-speed lines had not yet been upgraded to allow for running at that speed.

As for the aesthetics, Italy has more than its fair share of design houses that have, over the years, produced some stunning cars. It was to one of these, Bertone, that the joint venture turned to design the shape of the new train. The design brief was complex. Bertone was asked to come up with a style that represented “elegance and speed”, but it would have to include crash protection, meet driver visibility standards and also take account of the functionality of the headlights in terms of international railway standards.

The result was an elegant cab with an elongated nose that incorporated the crash protection structures. The joint venture team checked the submitted design, both theoretically and in the wind tunnel where drag coefficients and crosswind stability were assessed, and found that it didn’t need any changes. The Bertone design had ticked all the boxes.

Changed requirements

After two years of hard work, the design was ready. The team only had to wait for the official invitation to tender and then submit its proposal.

But…

When the documents were opened, all was not as expected. FS, and operator Trenitalia, was now looking for a train with a maximum operating speed of 360km/h, not 350. In addition, the train would have to be able to operate in seven countries across Europe and there was a requirement for condition-based maintenance.

With six months to revise the design, the team was re-established at Pistoia in Tuscany, home of AnsaldoBreda. Almost everything had to be checked and revised.

The new top speed had implications for the design of the bogies, power and control systems and pantograph. The aerodynamics and crosswind stability had to be rechecked. Room had to be found for a number of new signalling systems, although this would be passive provision with the trains to be delivered only with ERTMS level 2 and the legacy Italian system. Power supply and cubicles for other systems would be in place, in case other signalling was to be installed later.

Of course the joint venture’s competitor, Alstom, had the same challenges, but in the end it was Bombardier/AnsaldoBreda that won out.

“I believe we won as we had some special solutions that were appreciated by the customer,” Marco explained. One example of these was the provision made for customers in wheelchairs. As well as having space to park them, and access to the disabled toilet, the walkways are wide enough that a wheelchair can move about the train and visit the Bistro.

Production

An order for 50 eight-car trainsets, worth around €1.54 billion, was signed in September 2010. Detailed design commenced immediately and the first mock-up was shown to the world at Rimini on 19 August 2012. Now called the Frecciarossa 1000, it was also shown at InnoTrans that year where, being a mock-up rather than a finished train, it was parked on a pavement not the railway tracks. Still, the striking looks attracted a lot of attention.

Incidentally, also in 2012, FS retired the Eurostar name and the new trains were to be destined for the Frecciarossa (Red Arrow) service, representing the fastest trains. Other services are categorised as Frecciargento (Silver Arrow) and Frecciabianca (White Arrow).

The first actual train was unveiled at the Pistoria factory on 26 March 2013. In a short ceremony attended by representatives of both companies, as well as FS Group chief executive Mauro Moretti and Mrs Lilli Bertone, the new train was named ‘Pietro Mennea’ after the Italian sprinter and European 200 metres record holder who had died only five days earlier.

Testing commenced in August 2013 on the Genoa-Savona line and then moved to night time running between Milan and Bologna. To save time, five trainsets were involved in the testing programme, which included 10 per cent overspeed tests on a specially prepared length of line. During these, the train recorded an actual speed of 399 km/h.

Testing was complete by 25 April 2015, when the president of Italy, Sergio Mattarella, boarded the train in Milan for an inaugural run to Rome, where it arrived just three hours 39 minutes later.

Commercial services commenced in June 2015, with 36 trains in revenue service as of September 2016. Today, the final cars are in production and trains are leaving the factory at the rate of two every week. The last train will enter service next year.

Legacy and the future

So the joint venture between Bombardier and, now, Hitachi Rail Italy can be judged a success. A 10-year service contract for the trains has been awarded to the consortium by Trenitalia, worth €250 million. Work on the high-speed lines should shortly result in line speed being increased from 300km/h to the full potential of the train – 360km/h (224mph).

immagini_hricorporate00

There seems to have been true cooperation and collaboration between the two parties. Marco Saachi has stated that there were very few ‘black boxes’, in which one of the two companies hid their proprietary technology. The team used English as a common language although, by the end, the Bombardier engineers were quite fluent in Italian.

He then looked back at the whole experience of designing and producing the new train.

“It was a fantastic experience for all the people who worked on this project. It was a very important experience, unique really, to develop a train on this level. The customer has declared that, after three months of revenue service, it was the easiest introduction of a new train into service in their history. That is fantastic to hear.”

Also after three months, the train has hit all of its reliability targets. So would the two companies work together on another project?

“We already are,” Marco replied. “Having developed a good way of working on the Frecciarossa 1000, we (Bombardier Transportation and Hitachi Rail Europe) have jointly designed and bid for a new tube train for London. The success of our first project has shown that, by combining our strengths, we can have the best of both worlds and create a really compelling offer. Also, there are a lot of things we’ve learnt so, if the bid is successful, it will be easier the second time around.”

What is Marco’s abiding memory of the project? “To improve the functionality of the team, we had a meeting for three days in the Tuscan countryside, with support psychologists and everything. It was a great thing to do and, over some nice dinners, the team really came together well…”

There are some advantages in building a train in Italy!

Thanks to James Rollin (Bombardier), Adam Love (Hitachi Rail Europe) and Alessio De Sio (Hitachi Rail Italy) for providing the background material for this article.

Written by Nigel Wordsworth

And now Hydrogen Power – Alstom’s new fuel cell powered train

I first saw a hydrogen fuel cell locomotive four years ago, at the Stapleford Miniature Railway near Melton Mowbray in Leicestershire. A team from Birmingham University had entered a fuel cell powered one-fifth scale locomotive in the Institution of Mechanical Engineers’ Railway challenge. If someone had told me then that a full-sized fuel cell train would be launched just four years later, and that I would be writing about it, you could have “knocked me down with a feather” (on both counts).

It was therefore quite a surprise to be invited by Alstom to visit InnoTrans in September 2016 to witness a product launch that was widely speculated to be a fuel cell powered passenger train. This visit also included a tour of Alstom’s Salzgitter plant where these trains are being manufactured.

iLint launch

The world is committing itself to targets to reduce CO2 emissions, some of which are tough and with no obvious means of delivery.

It is frequently held that railways are inherently environmentally friendly due to the extensive use of electric trains. However, as the UK has learned, electrification can be very expensive and, increasingly, there are views that electrification might not be viable for any lines other than those attracting significant volumes of traffic. The challenge of significantly reduced or zero-carbon trains on non-electrified lines is therefore likely to remain.

In general, these un-electrified lines are operated by diesel multiple units. Just four countries, Germany, UK, Italy and France (in descending order), operate two-thirds of Europe’s DMU cars, and it is suggested that the annual market value of Europe’s DMU market is some €650 million.

The potential market is significant and Nick Crossfield, Alstom’s managing director for the UK and Ireland, explained that there is a very compelling argument for an electric train that doesn’t require overhead catenary. He added that Alstom has extensive experience with tram vehicles that do not require catenary, and he could foresee a time when catenary electrification would be confined solely to high density or, perhaps, heavy haul routes.

A fuel cell system adds another option to operators to provide high quality transport without the cost or visual intrusion of catenary systems. This, and the political context in Germany (below), led to the development of the Coradia iLint.

Up to now, hydrogen fuel cell proposals have suffered from the lack of ready sources of hydrogen and concerns about performance and range. Is this about to change? We will get to the iLint launch, but, as with most railway issues, the train in isolation doesn’t provide the answer. A carbon-free train requires a system solution, so we’ll start with the infrastructure.

System context

As Alstom’s launch was in Germany with a train for the German market, the German context is as good a place to start as any.

Clearly, any mass exploitation of hydrogen technology will require some sort of infrastructure to provide the fuel to enable relatively unrestricted operation of vehicles. This is usually more than any one organisation can manage. It needs political will to provide the environment and the infrastructure.

Germany has committed to reducing its CO2 emissions by 40 per cent by 2020 (compared to 1990) and to using 80 per cent renewable energy in its power supply mix by 2050. Given that about 50 per cent of German railways are not electrified, the need to reduce diesel operation is crucial if German railways are to play their part in delivering the target reduction in emissions. As hydrogen is a source that allows 100 per cent CO2-free traffic, Alstom signed a Letter of Intent (LOI) in 2014 with four German States (Lower Saxony, North Rhine-Westphalia, Hesse, Baden-Württemberg), and another LOI with one additional region (Calw) in 2015, for the development of a fuel cell train.

But where will the hydrogen come from and how will it be distributed? As part of its commitment, Germany has started to invest in a hydrogen generation plant and hydrogen distribution networks. Whilst these facilities may not yet be developed to permit extensive use, a train refuelling depot located next to a compressed hydrogen pipeline, servicing a captive fleet, is the ideal starting point for trials of hydrogen technology.

img_5122_ilint-interior_d

Manufacture of compressed hydrogen requires a great deal of energy, which could make hydrogen uneconomic, but Germany has invested heavily in wind turbine technology. As part of its energy mix, Germany is using the energy generated by the wind turbines to make hydrogen when electricity demand is low. This energy might otherwise have gone to waste, so can be regarded as almost free.

As this shows, the infrastructure is gradually becoming available and, because German regional transport authorities are pushing for the implementation of emission-free transport technologies, the scene is set for a truly zero- emissions train.

Andreas Knitter, Alstom’s senior vice-president for Europe, confirmed that Germany, with its Hydrogen Association and some support for development costs, was a good place to explore the benefits in practice.

Alstom Coradia iLint

Henri Poupart-Lafarge, Astom’s chairman and chief executive officer unveiled its zero emission train at InnoTrans on 20 September 2016. This is the Coradia iLint, a hydrogen fuel cell version of the Coradia Lint regional diesel mechanical unit which is available in a variety of configurations from single cars though to three car units.

On the Lint, each car generally has an underfloor diesel engine driving through a cardan shaft onto the adjacent bogie. The fuel tank is provided at the other end of the vehicle and, in between, there is a low floor section for reasonably level access at typical regional stations.

The iLint retains the same mechanical configuration to allow the homologation work to be restricted solely to the changes necessary to gain acceptance of the revised drive train.

The prototype trains will be two-car sets, approximately 54 metres long. On each of the two cars, the propulsion system will comprise:

  • Compressed hydrogen tanks on the mid-section roof of each car;
  • Hydrogen fuel cell on the trailing end roof of each car;
  • A body-mounted AC traction motor and converter;
  • A static auxiliary converter to provide power for the train’s systems and a lithium-ion battery pack to store energy recovered during braking, located in the trailing end underfloor space.

Alstom has partnered with experts in fuel cell and battery technology. The fuel cell (from Hydrogenics) takes hydrogen from the high- pressure fuel tanks (Xperion) and combines it with oxygen from the air to produce electricity with steam and water as a by-product. The fuel cell supplies the auxiliary converter, the lithium ion battery pack (Akasol) and the traction converter.

The efficiency of the system relies on the storage of energy in the lithium-ion batteries. Fuel cells tend to work at their best if they are run continuously at reasonably constant performance. The battery stores energy from the fuel cell when not needed for traction and from regenerative braking when the train’s motors turn kinetic energy into electrical energy. In short, the batteries store the energy not immediately required, in order to supply it later, as needed.

During acceleration, the power of the fuel cell will be used mainly to supply traction power demanded by the traction inverter and to supply the on-board systems (via the auxiliary converter), supplemented by power from the battery. The level of fuel cell power depends on the rate and duration of acceleration – short acceleration phases with limited power demand will mainly be supplied by the battery. Only during longer phases of high power demand will the fuel cell operate at full power.

During phases of lower acceleration, constant speed running or coasting, part of the fuel cell power will be used to recharge the battery and to supply the on-board systems. When the battery is fully charged, the fuel cell output will be reduced so that it only supplies the auxiliary converter/on-board systems. This will reduce hydrogen consumption.

During braking, the fuel cells are almost completely powered down. The traction inverter supplies the DC-link with electrical power generated by the motor from the kinetic energy of the vehicle. This power is used to supply the on-board systems and surplus power is used to recharge the battery, a feature that also saves hydrogen.

In service

The specification included a requirement for minimum change from the established Coradia Lint product and that the standard product’s top speed of 140km/h and range (on a single tank of fuel) of at least 600km be retained.

To successfully introduce a new energy source into routine service, a number of changes will be necessary, not least to depot infrastructure and maintenance arrangements. To make the deployment of the fuel cell system as easy as possible for operators, Alstom will be offering a complete package consisting of the train itself, its maintenance and the whole hydrogen infrastructure. This will allow the operator to focus on its core competence while Alstom and its partners take care of all rolling stock and hydrogen-related matters.

During the launch, Alstom officials were confident that, following homologation in 2017, and pre-service trials in 2018, the trains would be in passenger service by 2019. Moreover, they were also confident of receiving a fleet order by the end of 2016.

Testing and homologation will have to demonstrate that all the changes, both to infrastructure and to the trains themselves, meet the requirements that have been set and are safe. Alstom’s engineers will no doubt be considering the risks arising from the introduction of hydrogen (such as sparks during refuelling, or implications for crashworthiness) and lithium ion batteries (possible runaway failures – the launch coincided with the battery problems reported on a well- know brand of mobile phones).

Returning to the conversation with Messrs Knitter and Crossfield, and the cost of hydrogen fuel, readers may be surprised to learn that it is competitive with diesel – at least in Germany. Andreas Knitter added that Germany has an advanced strategy for rolling out the distribution network necessary for its successful introduction.

As for the opportunities for hydrogen in the UK, this was seen as more challenging than in Germany, partly, because the UK is less well advanced in developing hydrogen infrastructure, and partly because the train would have to be a new design, given the need to design for the UK loading gauge. That said, Nick Crossfield confirmed that Alstom is looking for a suitable UK opportunity.

Alstom Salzgitter

Alstom’s largest rail vehicle plant is in Salzgitter, some 68km south east of Hanover. It occupies a site of area 1.2 million square metres, of which 200,000 are occupied by workshops. Approximately 2,500 people work there.

The Salzgitter plant carries out train and bogie manufacture and wagon repair. Alstom’s activity in this part of Germany started in nearby Breslau when Gotfried Linke began manufacturing rail wagons in 1839. The Linke organisation eventually became Linke Hofmann Busch, before partial takeover by GEC Alsthom in the mid-1990s. It was finally wholly absorbed into Alstom Transport Deutschland in 2009.

Production at Salzgitter restarted in 1949 after a period making what were described as “other things”! In 2015, some 150 trains of various lengths were delivered, over 1,000 bogies manufactured and over 3,500 wagons overhauled.

Burkhard Reuter, operations director of the plant, and Christian Wiegand, global planning director for Germany/Austria, showed Rail Engineer around the facility.

The plant currently specialises in regional trains – particularly the Coradia range – Continental, Nordic and Lint. It is also manufacturing the DT5 U-Bahn cars for Hamburger Hochbahn.

Outline descriptions of the products in approximate order of vehicle size are:

  • Hamburg DT5 – This is an electric third-rail three-car set. The centre vehicle has two bogies and the end vehicles are suspended off the centre vehicle and mounted on one bogie each. They are constructed from stainless steel, partly unpainted and have open wide gangways through the set. Over 80 of these have been produced in a consortium with Bombardier.
  • Coradia Lint – A diesel-mechanical rail car design available as a single car, articulated two- car, bogie two-car or bogie three-car sets. They  are steel construction, with an entrance height of approximately 630mm or 810mm above rail. Each car’s power pack is rated at 335 kW or 390kW and they have a top speed of 140km/h. Over 900 trains have been built or are on order. The Coradia iLint is based on this series.
  • Coradia Continental – An electric rail car design available as three, four, five or six-car articulated sets. They are steel construction, with an entrance height of approximately 600mm or 800mm and suitable for 25kV, 50Hz or 15kV 16.23⁄ rd Hz electrical supply. Top speed is160km/h. Over 200 trains are in service with nearly another 200 trains on order or in production.
  • Coradia Nordic – Based on the Coradia Continental but with a wider carbody to take advantage of the Scandinavian gauge and additional winterisation features for extreme cold weather. They are steel construction, entrance heights are 610mm or 760mm and the top speed is 180km/h. It is currently produced in four and six car articulated sets and for 15kV 16.23⁄ rd Hz electrical supply. Over 300 trains have been built with another 70 trains on order/in production.

The scale of manufacturing plant necessary to build modern steel rail vehicles is impressive. It all starts with steel sheet (bodies) and plate (underframes), cut and shaped precisely and then welded in extensive jigs. Roof sheets are welded flat and then bent and welded to the curved roof frames. Jigs are arranged such that they can be rotated where necessary to allow access for welding to be carried out in the most advantageous way, and some of the welding is carried out in automated plant.

Seeing them side-by-side, it was noticeable that the only significant structural difference between the Continental and the Nordic versions of the Coradia is the flat sides of the former and the curved sides of the latter.

Underframes are necessarily formed of heavier sections than body sides and roofs and the structure on the front end of the end vehicles is even more massive so as to comply with the crashworthiness requirements specified in EN15227.

Once the individual elements have been completed, they are all welded together in a jig and then sent to what was described as the straightening shop which was not visited as it was described as “rather noisy”. This was probably an understatement! In this shop, the vehicles
are adjusted (cue heat and hammers) to correct inevitable distortion during welding. Following this process, the cars shells are sandblasted, inspected and then painted.

The next stage is fit out, using kilometres of cable, great lengths of pneumatic pipes, windows, insulation, doors, traction equipment, compressors, brake equipment, toilets, cladding, pantographs, gangways, floors, seats and luminaires, before the cars are ‘married’ to their bogies. Following that is a static test, and then a dynamic test on the plant’s own electrified test track. The final stage is cleaning and preparation, and then customer inspection.

At the end of the process, a shiny new train, off to carry passengers somewhere in Europe.

Written by Malcolm Dobell

Thanks to Will Roberts, communications director of Alstom UK, for organising the visit to InnoTrans and the factory and to the many Alstom employees who gave their time to support this article.

Photos courtesy of Alstom.