Welding Lines summer 2017

The newsletter of the Institute of Rail Welding

Summer - Issue 44

15th

Anniversary Edition

A personal perspective: Lois Appleyard What's in a weld?

Welding of rails of different wear, grade or profile Back Down the Line

WFCS for Rail - One year on

Member profile: Air Products PLC Latest Rail News

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A Personal Perspective: Lois Appleyard A new feature where members of The Welding Institute give a personal view on recent items in the news. In this edition, Lois Appleyard (Membership and Accreditation Manager) reviews an article first published in Rail Professional in September 2016.

‘I was struck by the maturity of this article which again raises the question, how do we engage women in engineering?

Membership of The Welding Institute might be a first step, or indeed any Institute, where young engineers can gain support and guidance as their career develops from more experienced colleagues. Only last year The Welding Institute formed The Tipper Group on Women in Engineering Day and the group has now formed a committee, hosted two lunchtime seminars with more planned and are organising a series of confidence workshops. As a female working in the industry, I fully appreciate the fascination of the engineering world but remain perplexed as to how we can tap into those qualities that women can bring to the sector. I think Vicky’s article gives a very pertinent insight and I hope you will take time to read, but more importantly ponder on the issue.’

Lois Appleyard From the ground up Vicky Corcoran, winner of the Ground Engineering Awards’ Rising Star category reflects on what inspired her to become an engineering geologist, and what it took to win…

In late June, while on a ‘break week’ from site work, several colleagues and I came together in a central London hotel for the annual Ground Engineering (GE) Awards. I was competing in the Rising Star category against some very strong competition – we’d all won our categories in the GE Next Generations Awards back in November 2015. The Rising Star category was first up, and I was over the moon to hear my name announced. As I collected my award, and smiled for the photographer, I was looking forward to watching the rest of the ceremony. While I watched, the majority of people receiving awards were male, and much older than myself. So I, as a young woman, seemed to be the odd one out.

Was it remarkable that I had won this award?

To win the award, we had been challenged to produce a STEM activity to inspire the next generation of geotechnical engineers and engineering geologists. Given the level of competition, I knew I needed an edge, so I started to think about why I’d become an engineering geologist, and the answer was simple: I’d been inspired by stories – stories where tragedy could have been avoided with a better understanding of the ground and its processes.

I’ve always had an interest in history, and the story of William Smith and his work on the Somerset Coal Canal gave me the basis of my STEM activity – the story of a working class man who became the first engineering geologist, and helped pave the way to the world we know today by making simple observations.

Smith worked in a time dominated by the male upper class,

although there were several notable female geologists around at the same time, namely Mary Anning, an early palaeontologist whose discoveries at Lyme Regis gained national importance, and Etheldred Benett whose work on the palaeontology and stratigraphy of Wiltshire contributed to the early geological maps of Britain.

Fast forwarding to the early 20th century, women continued to play a role in geotechnical engineering, such as Ruth Doggett Terzaghi who had a PhD in geology from Harvard where she lectured on engineering geology and worked alongside her husband, Karl Terzahgi (Peck, 1993). I also recently discovered, while on a boat trip along the River Thames, that Waterloo Bridge is nicknamed the Ladies Bridge (www.theladiesbridge.co.uk) by the boatmen as it was built mainly by women during the Second World War. In fact, it turns out that there were three times as many women in the construction sector in 1945 as there were in 2006. Although, having said that, along my row of desks in my office, four out of seven colleagues are women.

During my five years at Atkins (and in this industry), I’ve seen the number of women rise. I have several inspirational female role models within my office and I’ve never suffered any form of sexism or discrimination (positive or negative) in my professional life. I think this reflects the wonderful supportive environment that Atkins has created – my success in the Ground Engineering Awards is a direct result of that. I would never have even entered, let alone won, if it weren’t for the support and encouragement of my colleagues. I became part of this fantastic team because of the belief of several remarkable people, who saw a young, enthusiastic geology student, and gave her a chance to visit a site and gain valuable work experience.

So, was it remarkable that I, as a woman, won the Rising Star Award? No. There have always been women in ground engineering and I’m simply standing on the shoulders of those who have gone before me. I won my award as a result of finding an edge, a lot of hard work, and by using the skills I’ve developed while at Atkins, in terms of presentation and research.

If just one person reading this article is encouraged to use stories to inspire the next generation of ground engineers, or gives a student a chance to prove themselves, then that is worth everything.

Vicky Corcoran is an engineering geologist in Atkins’ Infrastructure business Peck, R.B. 1993. Memorial to Ruth Doggett Terzaghi 1903-1992, Geological Society of America, 24 91-92

www.iorw.org

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New website for IoRW

We are delighted to inform you that our new website has just launched.

The IORW has a new website! The new website has a fresh new look and feel, and we hope more user friendly. It is full of useful information but more content would be great to share with Members and to promote ideas and discussion. In particular we'd like your ideas on features and resources you

Cover Page Competition Anchor the prime position with your winning photo. We need high resolution photos of a rail weld related topic to put on the next front cover.

The winning picture will receive full credit and a half-page advertisement in Welding Lines, plus a free place at this year’s annual conference in York.

To enter please send your pictures by email to iorw@twi.co.uk to by post to: Institute of Rail Welding, c/o The Welding Institute, Granta Park, Great Abington, Cambridge, CB21 6AL, UK Deadline for entries is 30 June 2017. .

would like to be able to access on line. We'd like more technical content and case studies. We'd like details of your news and events. We'd like to make this a website for its Members by its Members. Have a look and send in your ideas and articles!

Visit www.iorw.org.uk for more information

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Member profile: Air Products PLC

by Hazel Harvey

A

s a leading industrial gas company Air Products works closely with the rail sector supporting project teams across a range of metal fabrication processes, from cutting and welding to sintering and brazing.

cylinders, reducing the risk of the cylinder falling while dramatically increasing its manoeuvrability during work. This makes it ideal for the mobile welding that is often necessary on rail projects.

With the pressure on for these businesses to operate faster and smarter, we are working collaboratively to identify opportunities for innovation and efficiencies, while ensuring the highest levels of safety.

The cylinders have a built-in regulator to control pressure, significantly reducing risk, and - because this regulator is protected and can’t be removed – the chances of regulator damage are minimised. Critically, the range doesn’t require spanners for connection or bottle keys to turn the valve on or off, and the oxygen and acetylene cylinder versions include safety features such as a built-in flashback arrestor that stops reverse flow of gas and flames to protect both the user and the equipment.

Our Integra® cylinder is a great example of this approach and was born out of growing, stringent safety regulations, and a need for speed and increased ease of use.

The Integra® cylinder range can be used to support any metal fabrication process. Supplied with a variety of gases, the Integra® cylinder is shorter and more stable than traditional

But safety and ease–of-use does not come at the cost of efficiency. When it comes to welding, due to the built in regulator and pre-set optimised weld flowrates, set-up time is reduced too.

The entire Integra® cylinder range feature a built in regulator which means users never have to spend time or money buying, repairing or calibrating regulators. What’s more is that every cylinder is filled using our 300 bar filling technology, so the gas goes further, meaning less restocking. More importantly is the built-in flashback arrestor which will allow connection of your regular equipment to the Integra® fitting of the Oxygen and acetylene cylinders.

However, even when restocking is necessary, Air Products can deliver newly filled cylinders using our specialist Gas Taxi® service vehicles. Our Gas Taxis® are smaller vehicles so they can respond faster and get to harder-to-access project sites – typical of many of our isolated rail lines. And because we have hundreds of sales and dispatch centres all across the country, we’re never too far away either.

By innovating with the industry’s needs in mind, we are successfully bringing new products to the market that can increase the efficiency of work while ensuring the highest levels of safety.

The supply chain has to do everything to support the needs of manufacturers and maintenance companies who are facing growing pressure to build and maintain rail infrastructure at ever increasing speeds and standards of safety. By working together, we can keep UK rail on track.

Air Products PLC

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Rail organisations missing out on apprenticeship levy benefits Neil Robertson, CEO of The National Skills Academy for Rail (NSAR) has warned that rail organisations could be missing out on substantial benefits.

The new Apprenticeship Levy regulations mean that employers with wage bills of more than £3million must put 0.5% of their payroll into the levy to fund new apprenticeships. The Government’s aim is to double spending on apprentices in England. Specifically, it is looking to create an additional 30,000 rail and road apprenticeships over the next 3 years.

A recent survey by City and Guilds of 500 organisations suggested that around a third of employers liable to pay the new Apprenticeship Levy from April are not even aware of its existence. Only a further third of organisations feel fully informed about the new rules with as many as 28% still unsure whether it would affect their business.

As part of its services to support the introduction of the levy, NSAR has designed and built a levy planner tool to help organisations assess its effects on their business. The planner enables them to quickly model the apprenticeship programmes to fit their needs, revealing how much of the levy contribution can be recovered. The levy planner is available to all NSAR members together with a range of consultancy services.

To find out more about NSAR’s strategic Levy planning services visit www.nsar.co.uk or contact mark.holmes@ nsar.co.uk

Save The Date!

4th October 2017

SEPT

4

Manufacturing - technical group meeting.

11th October 2017

Structural Integrity and NDT - Technical group meeting.

19 - 20th September 2017

Structural Integrity and NDT - Technical group meeting.

Investing in the future?

Staff are one of the biggest investments a company can make so supporting and encouraging staff development has got to be a priority for employers. Personal career development through membership of a professional institution and ongoing CPD can be a very cost effective way of investing in the future, both for the business and individual employees. It could also make employers an employer of choice for those thinking about future careers in engineering.

For those with engineering qualifications and/or extensive experience, professional membership of The Welding Institute might be an option. For more information check out our website; http://www.theweldinginstitute.com/ Professional registration with the Engineering Council is often a requirement for any competent engineer seeking employment. The Welding Institute is an accredited awarding body who offer advice and support to achieve professional registration. For more information, have a look at the Engineering Council’s Website; https://www.engc.org.uk/

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What’s in a Weld?

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he visual identification of a defective weld is often quite easy to diagnose, or so it would seem. In some cases the underlying causes are not so easy to establish. A hole within the head is in most cases attributed to an issue with either the consumables, typically a poorly stored/damp portion, or deficient preheat. However, this is not always the case as sectioning, and a careful examination of the weld can reveal substantially more detail than that initially visible during a visual inspection of the installed weld.

Consider the example of the weld below that was presented by a client for examination. The rejected weld was removed from track due to the presence of a 3bii defect (as described in NR/L2/TRK/0032 Table 1 – Weld Acceptance Criteria).

The dimensions of the defect on the running table were circa 5mm x 8mm on the surface and was probed to a depth of 28mm. Figure 1 shows detail of the defect exposed following finish grinding. In addition, a 3biii defect of circa 5 mm depth was observed in the centre of the weld collar around 30mm below the upper fishing radius. Figure 2 shows the position of this 3biii defect.

The defective weld was initially subjected to a visual examination. As the weld had been removed from track by flame cutting close to the edges of the weld collar, it was not possible to measure accurately the rail heights but these were in the region of 155mm and 157mm suggesting ~2mm of differential wear.

Details from the weld installation form indicated that the weld had been installed between new 56E1 260 grade rail and 3mm worn 113A 220 grade rail using 1 spot moulds. Visual examination revealed the moulds to have been well fitted with no flashing evident at the edges of the weld collar.

Upon further examination of the running surface defect, it was apparent that there was more to this weld than at first suspected. The weld was sectioned to provide a longitudinal vertical section through the running surface defect.

During polishing, a previously unobserved area of internal porosity (circa 12mm diameter) was found in the weld metal approximately 15mm above the base of the foot.

The prepared section was then etched using Fry’s reagent to provide a macro etched surface (Figure 3) from which the weld metal widths could be measured with respect to the depth below the running surface. These dimensions are given in Table 1. Unfortunately, due to the weld having being cut out of track as a narrow sample, the extent of fusion on the running surface and base of the foot could not be measured.

Figure 1: Photograph of the 3bii gas pore defect on the ground running surface of the defective weld.

Figure 3: Etched longitudinal vertical section through the defective weld showing the size of the defects and weld metal fusion widths and fusion profiles.

Figure 2: Photograph of the 3bii sand cavity defect in the weld collar of the defective weld.

Distance below running surface (mm)

Weld metal width (mm)

27

42

69

46

85

47

139

44

Table 1: Measured dimensions of weld metal width with respect to distance below the running surface.

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of examination will demonstrate that the welder has indeed followed the correct procedure.

Figure 4: Weld metal fusion profiles and HAZ from a typical weld approval sample.

Comparing the measured weld metal fusion widths from the rejected weld (Figure 3) with data from welds made during approval tests on 1 -3mm worn 56 E1 rail (an example of which is given in Figure 4), it was found that the weld metal fusion widths in the rejected weld were wider than would be expected. The implication of this is that the initial prepared weld gap was set too wide. The minimum weld metal fusion distance from the approval trials was found to be 35mm, whereas that from the rejected weld was found to be larger and of the order of 42mm.

It was also noted that the weld metal fusion profile on the worn side of the rejected weld had an unusual profile. It would normally be expected that the fusion profiles should be symmetrical either side of the weld metal. The asymmetry displayed in the rejected weld under examination is a prime indicator of the flame cut rail end not being of the required quality.

On sectioning the rail head through the initial defect, it was noted that the 28mm depth gas pore turned and extended horizontally towards the worn rail end at the bottom of the pore. A further longitudinal transverse section was therefore taken to expose this extension to the initially observed defect.

After polishing and etching in Fry’s reagent it was found that the overall pore length was circa 28mm below the running surface with the crack turning and extending for a further 10mm towards the worn rail end.

On the basis of these observations, there are several lessons that may be learned from just this one weld. Whilst there may be a perception that once a weld is installed, any evidence of mal-practice or non-conformance to the prescribed welding procedure may not be identified, the rejected weld presented here highlights that not to be the case. In this case, a ‘postmortem’ revealed that the weld had been cast between rail ends that were either set too far apart or between rail ends that had been prepared inadequately. Further, the evidence above shows that there are potentially indications within each alumino-thermic weld that can identify poor practice on the welder’s part. Conversely, and it should be emphasised that many alumino-thermic welds subjected to a similar level

The investigations highlighted above reinforces the message that welding parameters are there for a purpose and that welders should not ignore these. In particular it is important that attempts are not made to install welds when weld gaps are outside of the permitted tolerances. For all aluminothermic welds, the welding gap should be within the process suppliers recommended tolerances and both rail ends prepared with good clean cuts with a tolerance of +/- 2mm both laterally and vertically. If flame cutting is employed a cutting guide must always be used; free hand cutting is not permitted.

Clearly, there are steps that can be taken to verify the quality and dimensions of the welding gap retrospectively. Generally speaking, just because the weld has been installed, does not mean that evidence of poor practices during its installation cannot be uncovered.

Ian Banton (Technical development Manager) & Mick Wainwright (Welding & Training Manager) Thermit Welding (GB) Ltd

IoRW ties are now available to purchase for £13.50 Contact us by phone: +44 (0)1223 899567 or by e-maill: iorw@twi.co.uk or by post: Institute of Rail Welding c/o The Welding Institute Granta Park Great Abington Cambridge, CB21 6AL

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LATEST RAIL NEWS Adaptable train carriage ready for UK trials A reconfigurable train carriage system designed to allow trains to automatically switch between passenger and cargo modes is poised to undergo trials on the UK rail network. Developed by Cambridgeshire product development firm 42 Technology the so-called 'Adaptable Carriage' system allows the seats and tables within a passenger train carriage to be automatically stowed to create space cargo that would otherwise go by road. The system - which can either be retrofitted to existing carriages or integrated into new design - has been developed as part of a two-year programme funded

by RSSB (Rail Safety and Standards Board). According to 42 Technology the carriage features three key innovations: a concept that enables spare passengercarrying capacity on, for example, off-peak services, to be used for cargo; a forward-folding seat design that allows any rubbish left on seats to be tipped onto the floor for easier cleaning; and a sliding mechanism to configure the seats into a seated position and to lock them in position along the carriage. The reconfiguration process is fully automated, takes under three minutes to complete and as a result the 20 rows of seats in a typical passenger carriage (with four seats per row) can be compressed to create cargo space equivalent to the capacity of an articulated lorry.

The Engineer Newsletter, 12th May 2017

Digital railway focuses on capacity While work continues on three pilot applications of rail traffic management technology, David Waboso, Network Rail's Managing Director, Digital Railway, says that Network Rail has identified eight priority projects where the introduction of the European Train Control System could offer significant capacity and performance benefits. He sees digital train control as the key to extracting maximum capacity out of the existing infrastructure and believes that there are three main pillars to this strategy - ETCS, traffic management and driver advisory systems which will be forerunners to automatic train operation. He adds that it will be fundamental to include the supply chain in the entire programme and says that suppliers may be able to help finance installation and maintenance of the train control systems.

Railway Gazette International, May.2017. pp.38-41.

New hand-held switch point gauges can identify potential wheel climb risk Details a project in the US which aimed to provide railroads and transit systems with a set of practical gauges that track inspectors could use to evaluate the condition of switch points. Field evaluation of these gauges was performed in two steps: an initial evaluation, after which modifications were made to the gauges and the instructions, and a final field evaluation. During the two field evaluations, approximately 350 switches were inspected. The evaluations included direct correlation between the inspectors' assessments and the indication of the gauges, statistical analyses and Decision Tree analyses, all looking at the effectiveness of the gauges in identifying switch points which are in a condition that can contribute to or result in a derailment. The gauges were designed as simple 'go/no go' gauges to indicate whether a switch point passes or fails. Each gauge addresses a different failure mechanism and potential derailment condition. It was recommended that these gauges be made available to the railway industry, as well as to railway standards organisations.

Railway Track and Structures, Apr. 2017. pp.26-29.

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Predicting lateral buckling in rails Reports on the development of a self-contained computational algorithm for predicting lateral buckling in rails that is based on the large deformation EulerBernoulli beam theory cast within the finite element method. A significant feature of the model is the ability to account for the degradation of material properties within the track structure that result from cyclic loading and environmental conditions. Towards this end, the researchers have developed a model for predicting the coefficient of friction between the crossties and ballast as a function of loading history. The current research points to a new arena in track structure testing that will improve the safety and reliability of rail infrastructure systems, as well as improve the efficiency of maintenance operations. It is anticipated that the model under development will become available for calibration, validation and verification in the near future. Because the new algorithm is self-contained, it can be deployed without recourse to expensive commercial software. bore sounding and global stiffness inspections. Part 2 discusses compression through wave analysis methods.

Compression through wave analysis is an NDT system that allows the identification of the weakest link and so is more dependable when inspecting old timber bridges.

Railway Track & Structures, Apr. 2017. pp.10-12.

INNOVATION AND INSPIRATION 26th Technical Seminar of the Institute of Rail Welding Commemorating the 15th Anniversary of IoRW. 15th anniversary conference of the Institute of Rail Welding 6th July 2017 In Association with the Network Rail National Training Centre and the National Railway Museum, York.

The Institute of Rail Welding was formally launched in April 2002 with over 200 people attending the lunch event at the Royal Society in London. A great deal has changed since then, but the IoRW is still going strong and a number of special features have been included in this seminar to commemorate its 15th anniversary. These include: ●● Practical demonstrations show casing some of latest tools and equipment ●● High profile speakers from Network Rail and associates from the industry ●● Access to 300 years of history and over 1,000,000 of railway memorabilia at the National Railway Museum.

As well as reflecting on past achievements, the event will focus on key technical developments that affect rail welding.

As always, a team of high quality speakers has been assembled to deliver the technical programme. As well as reporting on recent developments in aluminothermic welding equipment, arc welding techniques, and in the deployment of mobile flash butt welding by Network Rail, the event will cover broader issues such as future opportunities for IoRW Members and the use of steel in modern railways.

Benefits of attending A team of well-known experts has been assembled in order to give a high-level, comprehensive and practical insight into all the world of rail welding.

By attending this event you will: ●● See at first hand demonstration of the latest equipment, materials and tools ●● Gain an better understanding of the latest technical developments in rail welding ●● Meet a wide range of suppliers, regulators and practitioners to develop ideas and debate issues.

Attendance is limited and therefore early enrolment is strongly encouraged!

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Back Down the Line – An overview of rail corrugation

C

orrugation is a large-scale problem on all rail networks, especially on metro or light rail systems. It is often found to be worse around curves and locally over sleepers.

Corrugation causes the train to vibrate, therefore the ride comfort suffers and the noise levels are increased. Additionally, these vibrations damage the track and the vehicles running along this track. Corrugation is remedied mainly by grinding the rail. It is estimated that the yearly cost of corrugation in Europe alone is €60 million[1].

What is rail corrugation?

Corrugation can be described as being a quasi-periodic (roughly periodic) irregularity on the running surface of a rail.

This essentially means that the rail exhibits a wear pattern which looks like a wave or a ripple, see Figure 1.

Figure 1 Example of Rail Corrugation[2]

Rail corrugation is described as having a wavelength (ƛ); this is the distance between two peaks of this wave. It is this rippled surface that causes three main detrimental effects on the rail system: 1. Poor ride – This is bad for the passengers and reduces the quality of the service provided by the train companies 2. Vehicle and rail damage – The high dynamic loads involved wear the track and damage the vehicle. The vibrations created can resonate through the sleepers and crack them, additionally, the vibrations introduce high cyclic loads into the systems and this can exacerbate fatigue damage on vehicle components 3. Noise – The vibrations cause excessive air-borne and ground- borne (vibrational) noise leading to more complaints from nearby residents.

What causes rail corrugation?

For corrugation to form a wavelength fixing mechanism is required which causes the damage (wear or plastic deformation). The wavelength fixing mechanisms all involve repetitive motions. A good example would be to consider the stiffness of the springs in the wheels suspension in a tram system. As a train/tram runs over the track the stiffness of the springs along with the mass of the train causes it to vibrate at a certain frequency: f = (k/m) – where k = spring stiffness (N/m), m = mass (kg) and f = frequency This frequency means that the train is bouncing along as it is travelling; this causes the dynamic load on the rail to vary up and down. This frequency can be used in an equation with the velocity of the train to calculate the wavelength of this bouncing: √= v/f – where e= wavelength, v L= velocity and f = frequency In the example of the tram system, all the trams will be very similar therefore the spring constants will be essentially the same and they will all be travelling at the same speed, therefore they will bounce along in the same manner.

Therefore the areas of high dynamic loading will occur in the same regions initiating wear or plastic deformation on the rail at these spots causing the wave pattern found in rail corrugation.

The wavelength fixing mechanism described above is not the only one, other mechanisms include: • Wheel slipping initiated by an irregularity (weld/joint for example) in the rail • P2 resonance where the ballast acts like a spring.

• First torsional resonance of the wheelset; the wheels oscillate in anti-phase, this is excited by joints and welds • Second torsional resonance; this phenomenon manifests itself as rutting on the inside of curves, the wheels are oscillating in the opposite direction to the drive gear • Pinned-pinned resonance; here the rails act like ‘guitar strings’ and the sleepers act like ‘frets’, ie the rail oscillates between the sleepers.

The exact damage mechanism is debated, the classical approach is to assume that certain areas are wearing faster than others, however, Oostermeijer[3] postulates that rail corrugation could be caused by plastic deformation.

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Monitoring and remediating rail corrugation Rail Rail corrugation can be detected using vehicle based equipment or a corrugation assessment trolley (CAT) such as the one made by Rail Measurement Ltd. This device measures the amplitude of the wave pattern of the corrugation, examples of this device are shown in Figure 2.

Different forms of rail corrugation Rail corrugation falls into three categories as summarised below: Short wavelength • e = 30 – 100mm • Causes many noise problems (associated with the "roaring rail" problem) • Occurs on straight track and on the high rail in curves • Associated with high speed passenger transit and light axle load operations Long wavelength • e = 100 – 300mm • Causes ride problems and vibrational damage • Occurs on the low rail in curves • Associated with heavy axle load freight operations Very long waves • e = 300 – 1500mm • Occurs on straight and curved track • Associated with very high speed operations.

It is worth noting that on a length of rail one or more categories may exist.

How to prevent rail corrugation The effects of corrugation can be reduced by speeding up or slowing down traffic on the line. The corrugation wavelength will be modified therefore a different area will wear and this is why a mixed traffic line commonly exhibits less corrugation.

Another way to prevent corrugation is to reduce the wear on the track. This can be done by lubricating the rail to reduce tangential forces or by improving the curving performance of the vehicle, this is why low rail is usually heavily corrugated.

It is debated what effect the hardness of the rail has on the prevalence of corrugation. Intuitively, harder rail steel will wear less rapidly, however, it has been noted that rail corrugation is more pronounced in rail with higher nitrogen content; this steel is stronger and more brittle.

The vehicle based equipment can collect data more rapidly but it is more costly than the CAT and is less sensitive.

Another method used for monitoring corrugation is to measure the noise levels when a train passes over the tracks, the noisier, the more severe the corrugation. Once detected, the corrugation is typically ground out. The European standard for corrugation is EN 13231-3 2006 (5). As the growth of corrugation is exponential it is best to grind little and often.

Conclusion Rail corrugation is a quasi-periodic irregularity on the surface of the rail of which there are three different main types.

Corrugation not only causes a noise issue but it also damages the track and vehicles. There are methods available to help mitigate rail corrugation but the most common approach is to monitor the corrugation and grind when necessary.

James redman

References 1. www.corrugation.eu/research/ 2. www.dlr.de/rm/en/Portaldata/52/ Resources/images/ neu-2009/wear.jpg 3. ‘Short Pitch Rail Corrugation – Cause and Contributing Factors’, Oostermeijer K, Holland Railconsult, Utrecht, www. uic.org/cdrom/2006/wcrr2006/pdf/481.pdf 4. www.railway-technology.com/contractors/track/rml/ rml1.html 5. ‘Controlling Irregularities in Rail to Reduce Noise’, Grassie S, 010

Join us!

IoRW is a Corporate Membership Institution. Membership subscriptions are determined by the number of employees of the Corporate member. Members have a position on the Management Committee and can nominate colleagues for free Associate membership of the Welding Institute. For more information, please contact us at IoRW@twi.co.uk Below: Committee Group Photo.

Published for members of the Institute of Rail Welding Š Copyright TWI Ltd 2017 Articles may be reprinted with permission from TWI Ltd. Storage of electronic media is not permitted.

Articles in this publication are for information only. IoRW and TWI do not accept responsibility for the consequences of actions taken by others after reading this information.

Printed and published by TWI Ltd, Granta Park, Great Abington, Cambridge CB21 6AL, UK Telephone +44 (0)1223 899000 E-mail: iorw@twi.co.uk Website: www.iorw.org IoRW is an activity of the Professional Division of The Welding Institute

Printed June 2017