Each year, the younger members of the Institution of Mechanical Engineers organise a seminar. The recent 2017 event, titled “Skills and Knowledge for the Future of Rail Engineering”, was attended by nearly 60 delegates. It was organised by Aoife Considine and David Lawes from London Underground, together with Timothy Van Ellemeet from Tailor Airey Limited and Gary Cooke from Eversholt Rail Group. They had lined up a broad range of speakers, which Rail Engineer summed up as “Inclusion, Innovation and Integration”.
Inclusion
Julianna Moats from WSP kicked off with an extremely thought-provoking presentation about the lack of diversity in engineering, and particularly in rail engineering. It is generally the case that good employers see the benefit of a workforce that represents the diversity of the community it serves.
She was particularly concerned that the UK is the worst in the world in terms of gender diversity, with females numbering just eight per cent of UK engineers – in rail it’s just four per cent. The situation gets even worse at more senior levels.
Research has suggested that companies which employ roughly equal numbers of women at board level are typically at least 20 per cent more profitable and create nearly 70 per cent more value than companies that are male-dominated.
Julianna suggested a number of approaches that companies might take to overcome the issue, and the whole engineering community needs to encourage girls to be interested in the creativity of engineering. She said that it is even necessary to emphasise that engineers wear business attire most of the time, not PPE!
That said, she complemented companies such as Crossrail that had illustrated women in engineering roles in publicity material. Her closing comment was to say that we should all “show, target, recruit, hire, mentor and promote diversity”.
Innovative Delivery Of Capacity
George Clark, TfL’s director of engineering, talked about the importance of innovation to delivering TfL’s mission to Keep London Moving. He reminded everyone that TfL carries 1.7 billion rail journeys per year and that road traffic has, over the last 25 years, increased by 23 per cent with only three per cent more road capacity.
Rail journeys are forecast to increase to 2.2 billion by 2021/22, following the completion of the Elizabeth line. London is also forecasting that its population will increase to 10 million by 2030, an increase bigger than the current population of Birmingham.
George’s role in TfL is to form a multi-mode, multi-disciplinary engineering team that can deliver innovative solutions to enable the increase in traffic that this increase in population will bring. He described examples of projects which typify the Underground’s challenge in accommodating more passengers. The Northern Line Extension to Battersea Power Station demonstrates the benefits of providing tube stations in an area of London poorly served by rail, and highlights some significant engineering challenges in designing a station that will have a tall building on top of it.
The planned Bakerloo line extension to Lewisham will unlock development along the Old Kent Road and enable a significant capacity increase on the existing line. The modernisation of the sub-surface lines on the Underground (District, Hammersmith & City, Circle and Metropolitan lines) is intended to deliver up to 33 per cent more capacity to satisfy demand.
The Bank-Monument station upgrade illustrates that it is just as important to get passengers to and from the trains as it is to move them from station to station; Bank is a notorious passenger interchange bottleneck.
George emphasised that innovation is required from engineers to deliver these upgrades more economically than ever, given that TfL’s central government grant is ending and income is further restricted by the Mayor’s fares freeze. He concluded by talking about the work of the National Skills Academy for Rail (he is a director) in developing a “virtual entity” of 34 training establishments together with TfL’s and Network Rail’s facilities to offer skills training, the cost of which can often be drawn down from the fund created by the Apprenticeship Levy.
Integration – Not Just Leaves
“Wheel/Rail Adhesion: Not Just Leaves on The Line” was the title of Neil Ovenden’s talk. Neil is engineering supply chain lead for the Rail Delivery Group and also chairman of the industry’s Adhesion Research Group (ARG), which comprises representatives from all areas of the railway industry.
Three safety-related issues tend to occur if adhesion is poor and/or if rails are contaminated; wrong-side track-circuit failures (WSTCF), signals passed at danger (SPAD) and station over-runs. He showed the statistics for autumn performance covering the period since 2000. The number of SPADs remains generally in single figures, there has been a clear improvement in the number of station overruns, whilst the WSTCF statistic remains peaky with no clear trend. In autumn 2016, there were five WSTCFs, 63 SPADs and 100 station over-runs.
The cost of autumn leaf fall (incidents, precautions, clearing up, repairs to wheel flats) is in the region of £250 to £300 million each year. Moving on to the theory; on clean, dry rail, the coefficient of friction (μ) between wheel and rail is typically 0.2 or better. For wet rails, the coefficient of friction might be in the range 0.1<μ<0.15. However, with contaminated rails, the value might fall to 0.05<μ<0.09 and, if heavily contaminated, μ might be <0.05 (less than 25 per cent of the nominal dry rail value).
Neil also stated that adhesion problems are not confined to autumn. Grease, oil, diesel fuel, moisture and substances deliberately applied to the wheels or rails can affect adhesion. Dry rails and thoroughly wet rails provide enough adhesion to deliver the required performance, but damp/moist rails can have really poor adhesion.
A value of μ<0.15 can harm a modern multiple unit’s ability to keep to timetable in motoring and μ<0.06 can harm a multiple unit’s ability to keep to timetable in braking. All this led ARG to ask the question: “What could be done to reasonably guarantee μ>0.06?” Neil described some of the research carried out to answer this question. First was T1077 – The Effect of Water on the Transmission of Forces Between Wheels and Rails – carried out for RSSB by Sheffield University. The output of this work will be fed into the industry braking model, Labrador, developed by Huddersfield University.
Magnetic track brakes have the potential to improve braking in poor conditions. Project T1099 explored the barriers to using these devices on National Rail since they are used on some main line railways elsewhere and virtually all tramways. As a result, a Railway Industry Standard – RIS/2710/RST, Design and Use of Magnetic Track Brakes – has been drafted and should be issued in early 2018.
Finally, project T1107 is exploring whether more sanders and more sand can deliver consistently good braking performance on poor adhesion (issue 157, November 2017).
Another speaker from TfL, London Underground’s head of innovation Rakesh Gaur, talked about the challenges of innovation, highlighting how some innovations can be quite unusual, such as an early means of insulating dwellings with cow dung!
Rakesh introduced the Gartner Hype Cycle for emerging technologies, illustrating that expectations from new technology can be over-hyped and there is a risk that good solutions might fail unless people manage them through the so-called Trough of Disillusionment.
He then discussed two of TfL’s successes. The first was to fit a monitoring system to approximately 300 track circuits on the Victoria line with minimal intrusion. As a result, service-affecting failures have been eliminated. The system has since been successfully extended to Central line track circuits, which were never designed for such monitoring.
Secondly, Rakesh mentioned how customers are much better informed about TfL services through the development of the smart phone, roll out of 4G services/WiFi and TfL making its data available to app developers. Citymapper, Bus Countdown and London Tube Status are just three of the apps that make London’s travellers’ lives just a little easier.
Crossrail
“Innovation at Crossrail: Pushing the Envelope” was given by Phil Hinde, Crossrail’s rolling stock and depots engineer. Phil emphasised that Crossrail had worked hard on innovation, notwithstanding a sponsor requirement to use only “tried and proven materials, techniques, technologies and systems”.
He illustrated a number of innovations: using tiny video projectors to improve the quality of on-site presentations/tool box talks, using thermal imaging to monitor progress of concrete curing, taking the opportunity to provide some ground heat pipes whilst piling was taking place, re-purposing grout shafts for the same application and the safe use of drones underground.
Crossrail operated an innovation programme with all its major suppliers and over 1000 ideas were submitted; both new and “pinched with pride”. Over 300 were implemented, and this has led to the creation of a Learning Legacy for other construction projects to access freely.
Moving on to the new trains, these nine-car, 205-metre EMUs (temporarily running as seven-car trains) have met the weight objective set at only 319 tonnes, an improvement of 20 per cent or better over previous modern EMUs. Reduced mass, combined with carefully tuned regenerative braking, delivers an energy effective train. All materials used were conventional, but deployed sensibly through aircraft-style weight management techniques.
Each car has three sets of doors per side, a National Rail first. They have wide, open gangways throughout the train, and the train has a capacity of at least 1500 people – staff have observed how these trains can “hoover” customers off the platforms.
They are smart trains – set up for condition-based maintenance while two of them will also monitor the infrastructure. They are fitted with several signalling systems – TPWS, AWS, CBTC with ATO and ETCS. The outer axle at each cab end is unbraked to provide reliable reference speeds for the CBTC, ETCS and wheelslide control systems. They are able to shut down most of the ‘hotel’ load (lights and HVAC) automatically when stabled. Finally, they are the first new trains without a yellow front, relying on powerful LED headlights to warn of their approach.
The mass saving has been achieved by the use of inside-frame bogies, longer cars together with good traction package design to control EMC without relying on heavyweight inductors. They have real time reporting to give load weighing and energy metering, and have the ability to update passenger information whilst in service and report wheel slide protection activity to inform low adhesion management.
Phil reminded delegates that all this requires good integration of sub-systems, good communications and good shore-based IT infrastructure. This needs to be backed by processes including configuration control, database discipline and cyber security. Phil concluded that the train has performed well since entering service, with a few issues needing to be fixed but the core mechanical and electrical design is looking very good.
Inclusion for passengers with disabilities
London Underground’s approach to “Accessibility: A Systematic Approach for Equal Access To Transport” was described by Alex Bennett, operational development manager and project engineer Zoë Dobell (yes, your writer’s daughter).
Alex reminded delegates that the Underground was built in a time when society’s attitude to disability was very different from today. It was only in the 1980s that it began to be recognised that people with disabilities had the same mobility rights as everyone else.
London’s DLR provided for people in wheelchairs from the beginning and the Jubilee line extension also had these facilities. Legislation in the form of the Disability Discrimination Act 1995 set the overall requirements for society and buildings, whereas special regulations were put in place for vehicles – the Rail Vehicle Accessibility Regulations (RVAR) 1998, revised in 2010 for metros/light rail/trams, and the Technical Specification for Interoperability for People of Reduced Mobility for National Rail.
For the Underground, there are two work strands; access from street to platforms and access to/from and within trains (their main topic). Alex and Zoë emphasised that access is not just about step-free routes and it is also necessary to remind people that RVAR is a legal requirement, with compliance required by 2020, and not a matter for business cases.
RVAR is generally goal-oriented legislation (such as colour contrast) but with some fixed requirements such as text height and the size of the step/gap between train and platform if a boarding aid is not to be provided.
Zoë outlined LU’s approach, which is to “do it right” and not merely to comply with the letter of the law. As an example, she illustrated the improvements made in-build or by modification to LU’s trains built since 1995, which now represents almost two thirds of the fleet.
Currently, Zoë is working on implementing modifications to the Bakerloo and Central line fleets to comply with the RVAR. Several changes are required – delivering colour contrast between the saloon and door areas inside the trains, providing spaces for wheel chairs, improved signage, and a new audio-visual passenger information system. Accompanying these changes is a CCTV security system and new LED lighting.
The most challenging modification is the removal of seats to provide the wheelchair spaces as LU trains have equipment under the seats that needs to be relocated. Zoë emphasised the importance of working with representatives of users during the design process, as mere compliance with the regulations might not deliver the best result; a better solution found at the design stage might not cost any more to implement.
Network Rail – Britain’s Biggest Builder
Matthew Steele, commercial and development director with Network Rail Infrastructure Projects, talked about “Engineering the Future of Network Rail”. He introduced his talk with some statistics:
- £6 billion enhancements and major renewals in 2016/17;
- 46 per cent reduction in operating costs since 2003/04;
- 400km track renewed in 2016/17;
- 22 per cent of all UK infrastructure being delivered by Network Rail;
- 15,500 live projects;
- £l2,000 being spent every minute;
- Everyone home safe every day.
Apropos safety, Matthew described a personal experience during the Great Western (GW) modernisation projects. He was in the site office on 28 December 2014 when a report came in that “at the Stockley Flyover construction site, on the Heathrow Airport branch line, a train had collided with a small trolley which was being placed on the line by track workers”. At the time, those receiving the report did not know whether the track workers were safe but fortunately they were.
Matthew said that, in the interests of getting the work done with minimum inconvenience to passengers, they had set up a complicated series of possessions which were changed frequently. With hindsight, this proved to be too complex.
He also described aspects of the GW electrification programme as far as Maidenhead for which he had been responsible. Some activities might not be recognised as part of “electrification”, such as replacing 183 point ends, resignalling, raising bridges, lowering track, cutting back canopies, and getting cable out of the ground.
One notable task was to divert a 132kV DNO (distribution network operator) supply at Iver. This involved the design and construction of a 1.5km subsurface cable diversion tunnel, 27 metres underneath a golf course and adjacent to the M25, along with two new overhead power cable towers. The cable diversion was completed without interruption to the power supply or train services, cost circa £5.5 million and was in the charge of a 27 year old project engineer.
Matthew concluded with some examples of technology helping to manage catastrophic structural asset failure; Network Rail’s biggest risk. These included LiDAR used from the air to identify trees at risk of collapse, underwater structure monitoring using sonar, and advances in photographic survey techniques using equipment packages in a single box that can be fitted to the front of a train.
Back to diversity
The President of the Institution of Mechanical Engineers, Carolyn Griffiths, delivered the closing keynote address and returned to the issue of diversity.
There are not enough engineers to satisfy today’s demand, let alone the forecast requirement, so the industry needs to work to attract more young people. An obvious solution is to increase the diversity of the engineering workforce and encourage girls to study STEM subjects.
With only four per cent of current railway engineers being female, just increasing that percentage will have a marked effect on overall numbers.
This article was written by Malcolm Dobell.
Could you please say where in the public domain that wheel rail contact is discussed in detail such that technical understanding can be progressed and advanced. My best regards, V A Cole, FIMechE.