Wheel Steel Handbook

Research Programme

EngineeringWheel rrolling ccontact ffatigue and rrim ddefects iinvestigation

Wheel SSteels HHandbook

Wheel rolling contact fatigue (RCF) and rim defects investigation to further knowledge of the causes of RCF and

to determine control measures

RSSB Wheel Steel Guide

Martin Clarke

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CONTENTS

ABBREVIATIONS AND ACRONYMS ..................................................................3 1 EXECUTIVE SUMMARY......................................................................................4 2 BACKGROUND....................................................................................................4 3 APPROACH .........................................................................................................5 4 WHEEL STEEL CHARACTERISTICS..................................................................6 5 WHEEL STEEL CHEMICAL ANALYSIS DISCUSSION: ....................................11 6 WHEEL STEEL MECHANICAL PROPERTIES DISCUSSION...........................13 7 SUMMARY .........................................................................................................16 8 ACKNOWLEDGEMENTS...................................................................................16 9 RELATED DOCUMENTS AND SPECIFICATIONS............................................16

Appendix I Wheel Chemistry Table .................................................................17 Appendix II Wheel Mechanical Property Table................................................18 Appendix III Old BR grades superseded Table ...............................................19 Appendix IV Wheel grade applications ............................................................20

Copyright 2008 Rail Safety and Standards Board. This publication may be reproduced free of charge for research, private study or for internal circulation within an organisation. This is subject to it being reproduced and referenced accurately and not being used in a misleading context. The material must be acknowledged as the copyright of Rail Safety and Standards Board and the title of the publication specified accordingly. For any other use of the material please apply to RSSB's Head of Research and Development for permission. Any additional queries can be directed to [email protected]. This publication can be accessed via the RSSB website: www.rssb.co.uk

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ABBREVIATIONS AND ACRONYMS

AAR Association of American Railroads BS British Standard BSEN European Standard with status of British Standard IRSS Indian Railways Standard Specification JIS Japanese Industrial Standard RCF Rolling Contact Fatigue RSSB Rail Safety and Standards Board TOC Train Operating Company V/T SIC Vehicle/Track System Interface Committee WSP Wheel Slide Protection

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1 EXECUTIVE SUMMARY The request for a guide of wheel steels detailing their metallurgical properties was identified by the Vehicle/Track System Interface Committee (V/T SIC) in their ongoing study of wheel rail interaction. This project was initiated to understand the effects of metallurgy, design and the manufacturing process on the initiation and propagation rates of rolling contact fatigue (RCF), and the development of a maintenance strategy to manage the RCF failure mechanism. This guide identifies the most commonly used and manufactured grades of railway wheel steels, and categorises them into a format that can identify similar grades or similar properties with an explanation of the relevant characteristics of each of the grade types.

2 BACKGROUND Train builders, maintainers, and operators are actively looking to improve total life cycle costs and safety of their wheelsets. Maintenance intervals on older fleets have increased, and on newer fleets with comparatively high primary suspension yaw stiffness operating on routes with sweeping curves, RCF has become a major issue on both wheels and rails. Current thinking suggests that RCF is associated with how wheelsets negotiate curves, but increased wheel loads and increased periods between reprofiling also have a significant effect. New designs and modern equipment have culminated in a shift in the mechanisms of wheel damage over the last 15 years. In 1992 when the last metallurgical survey was carried out by BR Research, about 80% of wheels were reprofiled due to thermal damage, largely as a result of inefficient wheel slide protection (WSP) systems. The other causes of premature wheel turning were identified as wear, including flange wear and thermal damage caused by wheel slide and tread braking. Today it is estimated that up to 80% of wheels are reprofiled due to RCF, and although an increase in total wheel life has been achieved, improvements are still sought. The GB maintenance market for wheels is typically 30,000 wheels per annum which is relatively small compared with the global market of approximately 5,000,000 wheels. Hence difficulties in supply to British and even European standards have been found. The current capacity of GB approved wheel suppliers or those seeking approval is as follows:

BVV - Germany 85,000 wheels per annum CAF - Spain 45,000 wheels per annum Lucchini UK/Italy 120,000 wheels per annum Bonatrans Czech Rep. 170,000 wheels per annum Maanshan - China 900,000 wheels per annum

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SMR - Romania 70,000 wheels per annum Standard Steel - USA 200,000 wheels per annum MWL - Brazil 50,000 wheels per annum Valdunes - France 130,000 wheels per annum Total 1,770,000 wheels per annum

On a cost and design basis, new wheel standards have been introduced over the last 10 years, particularly wheels to Association of American Railroads (AAR) standards. These are more widely used in both quantity and geography, and therefore are more readily available. More recently, due to the instances of severe and low mileage RCF, new steels have emerged that contain higher levels of silicon and manganese. The use of new steel grades to differing standards involves raising a deviation to the Railway Group Standard. This process ensures that deviations to the standards will not introduce risk to the railway. This can be a costly, arduous and time consuming process for train operating companies (TOCs) to bring about wheel material change. There are currently three deviations in force at this time covering materials change. It is hoped this guide will assist in enabling deviations to be approved more efficiently and at reduced cost. 3 APPROACH The railway wheel steels have been categorised in three stages, and the bulk of the technical information is contained in the Appendices where it is easier to see the similarities between standards in tabular form. The three stages are:

1. Chemical analysis verification

2. Heat treatment condition

3. Mechanical property verification

The first stage of categorisation is chemical analysis. The chemical composition of the steel defines the level at which the mechanical properties can be achieved. The wheel steel analyses for national, international and bespoke steels are shown in Appendix I. The second stage defines how the chemical analysis will be utilised by heat treatment to achieve the final mechanical properties. The most common processes for heat treating wheels are normalising, fully immersion quenching, and tempering and rim quenching (chilled), and tempering. Normalised wheels, although still acceptable, are no longer manufactured for rolling stock operating on Network Rail controlled infrastructure, and older designed class C wheels were replaced by rim chilled and tempered wheels (R8T) from about 1993. This change was implemented to incorporate the material grades referenced in British Standard (BS) 5892 Part 3. This standard is based on UIC812-3, and so in essence this change was to move towards

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adoption of European grades. The old BR supersession table from WOSS612-10 is shown in Appendix III. The rim properties of fully quenched and rim quenched wheels are similar. This guide is intended to facilitate more effective management of wheel damage that occurs at the wheel/rail interface and concentrates on the aspects relating to rim quenched wheels, where more detailed information is more common and widely available. The third stage is verification by mechanical properties. The mechanical properties required by material specifications are achieved by a specific heat treatment appropriate to the chemical composition and the desired properties required for the finished wheel. The wheel steel mechanical properties for national, international and bespoke steels are shown in Appendix II. 4 WHEEL STEEL CHARACTERISTICS The following discussion is considered to be representative of the latest technical information available on wheels for design, manufacture, stresses in wheel treads and wheel failures. The British Standard and European specifications for railway wheels describe classes of heat treated wheels. The choice of the class of wheel to be used for any particular type of rolling stock and service is based on the conditions to be met. Wheel life depends largely on the resistance of the wheel to wear and its immunity to tread failures caused by thermal cracking and shelling as a result of RCF. Wear of wheels occurs on the wheel tread and flange. This can be minimized by correct alignment of the wheels, flange lubrication, material of wheel and rail being similar and equipment in proper mechanical condition. Every effort should be made to avoid the abnormal loss of tread metal caused by thermal cracking and shelling. The most effective form of flange wear reduction is by flange lubrication, which can reduce wear by at least six times [9]. Where this is cost prohibitive or not practical, wear can be improved by increasing the carbon content of the steel, and by promoting the morphology of the pearlite microstructure by altering the quench rate. A typical wear profile is shown in Figure 1.

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Figure 1 Example of flange and hollow wear (units in mm) Tread Damage occurs from a number of mechanisms including severe tread braking at high speeds or high speed slip, caused for example by faulty WSP systems or WSP activity combined with low adhesion conditions, resulting in a heat input into the wheel tread. The effect on the tread of the wheel is to produce a layer of martensite on the surface of the wheel. Martensite is a phase of steel formed whilst wheels are in traffic, created due to heating and then rapid cooling, and is very hard and brittle. Martensite forms as a result of localised heating of the wheel tread surface up to 1000C. This locally heated metal then quenches rapidly due to the colder bulk material of the wheel, which acts a heat sink, and thus produces the metastable phase martensite. This phase is typically 20-30mm wide and 1mm deep. A typical example is shown in Figure 2. Its volumetric size is larger than the pearlitic base of the wheel from which it is formed, and therefore is in compression. The pearlitic material immediately below is in tension and resists the expansion of the martensite which then becomes slightly stressed. The continued rolling of the wheel initiates cracks in the martensite which breaks away, and the cracks may propagate into the pearlite. This damage on the wheel tread may develop into larger cracks through rolling contact and thermal input and must be turned out. Resistance to thermal damage can be improved by lowering the carbon content of the steel. There are also other tread damage mechanisms such as thermal fatigue, which is associated with tread braking, but would generally be worn away due to the action of scraping whilst braking on the tread. Low speed slide can induce local heating below the transformation temperature and at an increased depth. The temperature is high enough, however, to overload the wheel due to loss of strength as the temperature increases which leads to mechanical damage of the wheel tread in the form of a flat.

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Figure 2 Example of wheel slip/slide damage Rolling Contact Fatigue is the failure of the wheel tread due to cyclic fatigue. In Britain, there are two notions of rolling contact fatigue; a) Generally fatigue of the tread contact area due to high loads leading to shelling of

the surface, an example is shown in Figure 3. This surface breakdown can be greatly accelerated if abnormal conditions exist and may occur under relatively light static loads.

b) Curving forces experience by the wheel will also cause rolling contact fatigue of the wheel tread; it is generally seen off centre of the tread towards the field side. This type of rolling contact fatigue is generally associated with the low of an axle in a curve and leads to chevron type indications on the field side of the tread, as shown in Figure 4. It can occasionally be seen towards the flange root on some wheels and is attributed to the action of the high wheel in curves.

Figure 3 Example of shelling

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In Britain, another type of rolling contact fatigue is common, off centre from the rolling contact region of the flange on the field side of the tread. This is thought to be initiated during curving and is associated with the low wheel on the trailer axle of an axle in a curve, and leads to chevron type indications on the centre/outside section of the tread. This can be seen in Figure 4.

Figure 4 Example of chevron RCF damage Resistance to fatigue is provided by increasing the strength of material in the tread. Vacuum degassing benefits fatigue resistance by reducing hard inclusions which are deleterious to fatigue life. In estimating the carrying capacity of a wheel, its diameter as well as the load is considered. The larger the diameter, the greater is the area of contact between wheel and rail and the lower the contact stresses for a given wheel load. For this reason larger diameter wheels can withstand larger wheel loads. Fatigue failures of wheels can be surface induced, where initiation is due to gross plastic deformation of the wheel close to the running surface. This is normally due to high loading and/or low material strength, and leads to cracks that grow some millimetres into the wheel before deviating back to the surface and leading to small sections falling away from the tread. This is a progression from the initial RCF crack initiation shown in Figure 3 and 4. Sub surface fatigue failures occur below the running surface and initiate on a macroscopic defect, although they can occur in a virtually defect free material if the stresses are too high. These defects can typically grow to 30mm below the tread before deviating back to the surface, so larger sections of the tread can break loose. This type of failure is therefore potentially very serious as can be seen in Figure 5.

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Figure 5 Example of RCF wheel failure with typical beach marks clearly visible. The following factors are found to be detrimental to wheel fatigue life:

High wheel loads High impurity levels Small wheel diameters Small rail radius Tensile residual stresses

Other damage mechanisms related to premature wheel tread turning are local tread collapse, indentation damage, rim face bulging, and tread roll over. High strength and higher carbon content are required for maximum resistance to shelling. On the other hand, thermal cracking is minimized by lowering the carbon content. These two causes of failure, thermal cracking and shelling, call for remedies which are the opposites of each other. For this reason, it is not possible to precisely specify the appropriate class of wheel for the severity of service which develops under various conditions. The following five factors have an important influence on the wheel life:

Static stress in the wheel tread Maximum train speed Braking requirements Track conditions Design and condition of equipment

Some guidelines on wheel materials used and applications on railway networks are included in Appendix IV.

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5 WHEEL STEEL CHEMICAL ANALYSIS DISCUSSION: Wheel steel chemical analyses are shown in Appendix I. Steels used for the manufacture of railway wheels are classified as carbon steels. Carbon steels can contain up to 1.65% manganese, 0.60% silicon and 0.60% copper with all other elements at residual levels. Railway wheel materials within the carbon steel group are generally classed as medium carbon steel with some wheel steels classed as high carbon. The microstructure as manufactured is referred to as pearlitic. However the lower/medium carbon steels also contain a ferrite phase which is more ductile, and adds a more resilient, impact resistant and more ductile element to the hard pearlitic structure. Most alternative wheel microstructures have been investigated, but in spite of this and lack of alternatives it appears that pearlitic steels offer the best performance, are inexpensive and are well understood. Carbon steel classifications are illustrated in Table 1.

Carbon steel Classification

Carbon % Manganese %

Low

braking and slip, because it is easier to produce brittle martensite in high carbon steel, and this phase of a railway steel is more liable to thermal cracking when the wheel is braked on the tread. The resistance of the wheel to brittle fracture is reduced as the carbon content increases, and it is therefore undesirable to use a high carbon wheel in a service where tread braking or slip is at its most severe. The effect of carbon on the susceptibility of a wheel to thermal damage is complex and is difficult to predict. Lower carbon wheel steels are prevalent in continental Europe, where the focus has been to avoid catastrophic failure on tread braked wheels during heavy braking such as that experienced in mountainous regions. It is the experience in Europe that lower carbon wheel steels have a higher martensite formation temperature and decreased brittleness. This factor assists in the reduction of martensite formation, and its effect once formed, and therefore leads to reduced thermal damage on wheel treads. There is evidence that lower carbon steels reduce the quench sensitivity and therefore further reduce the amount of martensite formed. This experience has meant that for similar applications, the Europeans have adopted lower carbon grade steels R6 or R7, whereas UK and other railway bodies have kept higher grades such as R8. This is represented in Appendix IV. Manganese has a similar effect to carbon in increasing the strength. Manganese also improves toughness, but it also makes the wheel more prone to thermal cracking. Differing from carbon, however, it does not have such a detrimental effect on the resistance to brittle fracture. Manganese also improves the depth of hardening, important in wheels throughout their service life, through many reprofilings. Manganese also increases high temperature strength. Silicon is normally added during steel making, acting as a deoxidant to the steel to reduce the oxygen level by reacting to form silicate inclusions, which are preferred to the iron oxide (FeO/Fe2O3/Fe3O4) inclusions. Increased silicon reduces ductility and impact values. It increases tensile and yield strengths. Silicon increases strength through solid solution strengthening in ferrite and by increasing the temper resistance. It also increases hardenability, much the same as manganese. Silicon also increases high temperature strength. Sulphur is controlled or added during steelmaking to help control hydrogen cracking in mainly non-vacuum degassed steels, and also to assist in machining where it allows swarf to break more easily. Historically at the start of the 1990s the sulphur levels were 0.030/0.047%. The levels today are typically 0.005/0.015%, with some steel manufacturers making steel with 0.005% or less sulphur. These levels are required to achieve the BSEN13262 specification levels, and are also required to achieve the benefits of clean steels, which improve cleanliness, ductility and fracture toughness. Aluminium is added to wheel steels to develop an inherently fine grained structure and this is generally found to be advantageous. Fine grained steels have improved strength, toughness and fatigue resistance. The typical range of aluminium is 0.018/0.050%, but can be controlled to tighter limits if required. The lower limit 0.018% is the guide taken from BS970, and the higher limit based upon economical steelmaking practice, and the need to ensure alumina inclusions are not an issue in the end product. The aluminium content is not a requirement of any of the national specifications, but is quoted by manufacturers and steelmakers alike to ensure fine

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grained steel. Fine grained wheels to the same analysis and strength as coarse grained wheels are much more resistant to thermal cracking and have better mechanical properties. Aluminium can also have a slight effect on the hardening of the wheel during heat treatment, which is not always beneficial, and as mentioned earlier, may also give rise to undesirable alumina inclusions. Chromium and Molybdenum are added to improve wear resistance and form very hard wear resistant stable carbides in the steel. Wheels with chromium >0.30% and molybdenum >0.08% would not normally be used in services where they would be likely to encounter a combination of very severe loading and abnormal braking conditions as these alloying elements, combined with the carbon level, would render them somewhat susceptible to thermal cracking. They would be suitable for use in stock equipped with disc brakes, where tread braking is avoided. Chromium and molybdenum both increase high temperature strength. Vanadium promotes the formation of stable carbides, fine grained structure, toughness, ductility and mechanical strength. Most specifications limit the residual elements (nickel, copper, tin, chromium, molybdenum and vanadium), but if not, these are controlled by the steelmaker to ensure that they are not so high as to detrimentally affect the properties of the steel. Some residual elements are added deliberately in carbon steels, as explained, to confer certain improved properties on the wheel, but their use as alloys adds to the cost of the steel, especially nickel. Copper and tin are usually regarded as undesirable due to their influence on the manufacturing process with regards to hot cracking. 6 WHEEL STEEL MECHANICAL PROPERTIES DISCUSSION The mechanical properties of wheel steels are shown in Appendix II. The ability to achieve the mechanical properties of each wheel grade is only achievable with a controlled chemical analysis which is not quoted in national standards, but each manufacturer has its own internal specification. This is generally a controlled amount of carbon, manganese and possibly chromium. Wheels that are rim chilled contain compressive residual stress, which further enhances the tensile properties. This effect can be as much as 300 N/mm2. The residual stress also has an effect of safeguarding crack growth, especially from wheels with thermally initiated cracks in tread braked wheels. Rim chilling is a process whereby jets of water are directed onto the tread during heat treatment, and the section of wheel close to the tread of the forged wheel is effectively water quenched. The cooling rate at the tread is very high and slows towards the centre section of the rim, and towards the rim/web transition and web where the wheel is effectively normalised (a high temperature anneal).The cooling rate and therefore hardness reduces through the section of the rim. A representation of the wheel tread is shown in Figure 6. This means that the tread of the wheel is quite hard, at the 5mm position, and can be as hard as 285BHN. Hardness reduces towards the last wear groove at the 35mm position, and can typically be as low as 255BHN. Wheels will therefore be more resistant to RCF when new, than when they are reprofiled, or close to their last reprofiling.

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Figure 6 Representation of hardness difference in rim chilled wheels

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The effect of tempering, which in railway wheel materials is effectively a stress relieve, is shown in Figure 7.

Figure 7 Effect of tempering temperature on residual stress in wheel rim It can be seen that the higher the tempering temperature, the less residual stress remains in the wheel. A balance, however, must be achieved in selection of the tempering temperature to achieve the required tensile properties versus leaving too much residual stress in the wheel and leaving the wheel prone to either distortion or cracking. Note that the compressive residual stresses created in service, at the contact patch, are significant and are believed to be higher than the manufactured compressive stresses. Wheels with web mounted disc brakes can develop large hoop tensile stresses in the web. These form as a result of the compressive yielding during braking due to restrained thermal expansion. These stresses can approach the yield point, and cause small fatigue cracks at the bolt holes with the possibility of growth and failure. High wheel web strengths should be avoided to reduce the residual stress levels.

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7 SUMMARY To categorise wheel steels to resist certain forms of damage, a broad summary is as follows:

To resist RCF, high tensile steels are preferred, which invariably incorporates increased carbon steels.

To resist thermal damage, lower carbon steel is preferred. To resist wear, including flange wear, an increase in carbon is preferred, and

an improved quench during manufacture. Changes in steel, however, are not as significant as effective lubrication.

Wheel steels specific to RCF resistance, thermal damage, or wear whilst improving one problem may exacerbate other problems. It is therefore necessary to prove by trial that the demonstrated improvements outweigh any deterioration in other properties. 8 ACKNOWLEDGEMENTS The author would like to acknowledge the particular assistance of the following in the drafting of this wheel guide: Bombardier Transportation UK Ltd. Lucchini UK Ltd. Valdunes 9 RELATED DOCUMENTS AND SPECIFICATIONS 1) BS5892: Part 3:1992 2) BSEN13262:2004 3) AAR M107/M208:2004 4) IRSS R19:1993 5) IRSS R34:1999 6) JIS E5402-1:2005 7) American Iron and Steel Institute Wrought steel wheels Product Manual. 8) British Steel Research Report PROD/ENG/6701/-/73/A Residual Stresses in

Railway wheels Effect of Tempering. 9) The Development of Improved Pearlitic Wheel Steels (EC) K.J Sawley March

1992. 10) Rolling contact fatigue of railway wheels - Anders Ekberg Chalmers

University of Technology 2000. 11) Railway Wheel Flats - Johan Jergeus Chalmers University of Technology

1998.

Appendix I Wheel Chemistry Table WHEEL STEEL CHEMICAL ANALYSIS LEVELS STANDARD COUNTRY GRADE CARBON SILICON MANG. PHOS. SULP. CHROME COPPER MOLYB. NICKEL VAN. CR+MO+NI HYDROGEN

OF ORIGIN % (MAX) % (MAX) % (MAX) % (MAX) % (MAX) % (MAX) % (MAX)

% (MAX)

% (MAX) % (MAX) % (MAX) PPM (MAX)

CAT1 CAT2 JIS E5402 JAPAN C44 0.46 0.40 0.90 0.040 0.040 0.30 0.30 0.08 0.30 0.05 N/S N/S N/S AAR M107* N.AMERICA L 0.47 0.15/1.00 0.60/0.90 0.030 0.005/0.040 0.25 0.35 0.10 0.25 0.04 N/S N/S N/S BS5892:PT3 UK R6T 0.48 0.40 0.75 0.040 0.040 0.30 0.30 0.08 0.30 0.05 0.60 2.0# 2.0# EN13262 EUROPE ER6 0.48 0.40 0.75 0.020 0.015 0.30 0.30 0.08 0.30 0.06 0.50 2.0 2.5 JIS E5402 JAPAN C48 0.50 0.40 0.90 0.040 0.040 0.30 0.30 0.08 0.30 0.05 N/S N/S N/S GOST 10791 RUSSIA GRADE 1 0.44/0.52 0.40/0.65 0.80/1.20 0.035 0.030 0.30 0.30 0.08 0.30 0.08/0.15 N/S 2.0 2.0 BS5892:PT3 UK R7T 0.52 0.40 0.80 0.040 0.040 0.30 0.30 0.08 0.30 0.05 0.60 2.0# 2.0# EN13262 EUROPE ER7 0.52 0.40 0.80 0.020 0.015 0.30 0.30 0.08 0.30 0.06 0.50 2.0 2.5 IRSS INDIA R19 0.52 0.15/0.40 0.60/0.80 0.030 0.030 0.25 0.28 0.06 0.25 0.05 0.50 3.0 3.0 JIS E5402 JAPAN C51 0.54 0.40 0.90 0.040 0.040 0.30 0.30 0.08 0.30 0.05 N/S N/S N/S VALDUNES FRANCE R8TUCS 0.54 0.30/1.10 0.60/1.10 0.020 0.005/0.020 0.30/0.50 0.30 0.08 0.30 0.06 0.65 2.0 2.5 FSR FINLAND ER8MOD 0.52/0.56 0.90/1.10 0.90/1.10 0.015 0.006 0.30 0.10 0.08 0.30 0.08 0.05 2.0 2.0 LUCCHINI ITALY SUPERLOS 0.49/0.56 0.60/1.10 0.60/1.10 0.015 0.020 0.30 0.30 0.08 0.30 0.08 0.05 1.8 1.8 BS5892:PT3 UK R8T 0.56 0.40 0.80 0.040 0.040 0.30 0.30 0.08 0.30 0.05 0.60 2.0# 2.0# EN13262 EUROPE ER8 0.56 0.40 0.80 0.020 0.015 0.30 0.30 0.08 0.30 0.06 0.50 2.0 2.5 AAR M107* N.AMERICA A 0.47/0.57 0.15/1.00 0.60/0.90 0.030 0.005/0.040 0.25 0.35 0.10 0.25 0.04 N/S N/S N/S JIS E5402 JAPAN C55 0.58 0.40 0.90 0.040 0.040 0.30 0.30 0.08 0.30 0.05 N/S N/S N/S BS5892:PT3 UK R9T 0.60 0.40 0.80 0.040 0.040 0.30 0.30 0.08 0.30 0.05 0.60 2.0# 2.0# EN13262 EUROPE ER9 0.60 0.40 0.80 0.020 0.015 0.30 0.30 0.08 0.30 0.06 0.50 2.0 2.5 GOST 10791 RUSSIA GRADE 2 0.55/0.65 0.22/0.45 0.50/0.90 0.035 0.030 0.30 0.30 0.08 0.30 0.10 N/S 2.0 2.0 TB/T 2708 CHINA CL60 0.55/0.65 0.17/0.37 0.50/0.80 0.040 0.040 0.25 0.25 N/S 0.25 N/S 0.50 N/S N/S GOST 10791 RUSSIA GRADE 3 0.58/0.67 0.22/0.45 0.50/0.90 0.035 0.030 0.30 0.30 0.08 0.30 0.08/0.15 N/S 2.0 2.0 JIS E5402 JAPAN C64 0.67 0.40 0.90 0.040 0.040 0.30 0.30 0.08 0.30 0.05 N/S N/S N/S AAR M107* N.AMERICA B 0.57/0.67 0.15/1.00 0.60/0.90 0.030 0.005/0.040 0.25 0.35 0.10 0.25 0.04 N/S N/S N/S IRSS INDIA R34 0.57/0.67 0.15 MIN 0.60/0.90 0.030 0.030 0.25 0.28 0.06 0.25 0.05 0.50 2.5 2.5 AAR M107* N.AMERICA C 0.67/0.77 0.15/1.00 0.60/0.90 0.030 0.005/0.040 0.25 0.35 0.10 0.25 0.04 N/S N/S N/S

JIS E5402 JAPAN C74 0.77 0.40 0.90 0.040 0.040 0.30 0.30 0.08 0.30 0.05 N/S N/S N/S

LIMITS SPECIFIED ARE MAXIMUM UNLESS SPECIFIED OTHERWISE # 2PPM LEVEL AS REQUIRED BY RAILWAY GROUP STANDARD GM/RT2466 * AAR SPECIFICATION ALSO HAS AL 0.060 MAX, TITANIUM 0.03 MAX AND NIOBIUM 0.05 MAX.

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Appendix II Wheel Mechanical Property Table WHEEL STEEL MECHANICAL PROPERTY LEVELS

STANDARD COUNTRY GRADE YIELD UTS A Z CHARPY U CHARPY V CHARPY V FRACTURE CLEANLINESS ULTRASONIC BRINELL HARDNESS

OF ORIGIN N/MM2 N/MM2 % (MIN) % (MIN) 20C J. (AV) -20C J. (AV) -40C J. (AV) TOUGHNESS REQUIREMENT STANDARD DEFECT LEVEL HB

* (MIN) (MIN) (MIN) N/MM2M CAT1 CAT2 CAT1 CAT2

JIS E5402 JAPAN C44 N/S 770-890 15 N/S 15 N/S N/S N/S NO N/S 197-277

AAR M107 N.AMERICA L N/S N/S N/S N/S N/S N/S N/S N/S YES 1.6MM 197-277

BS5892:PT3 UK R6T N/S 770-890 15 N/S 15 N/S N/S N/S NO 2MM# 229-262

EN13262 EUROPE ER6 500 MIN 780-900 15 N/S 17 12 N/S 100 MIN YES 1MM 2 OR 3MM$ 225 MIN

JIS E5402 JAPAN C48 N/S 820-940 14 N/S 15 10 N/S N/S NO N/S 235-285


EN13262 EUROPE ER7 520 MIN 820-940 14 N/S 17 10 N/S 80 MIN YES 1MM 2 OR 3MM$ 245 MIN 235 MIN

IRSS INDIA R19 410 MIN 820-940 14 N/S 15 N/S N/S N/S NO 3.2MM 241-277


BS5892:PT3 UK R8T N/S 860-980 13 N/S 15 N/S N/S N/S NO 2MM# 255-285 EN13262 EUROPE ER8 540 MIN 860-980 13 N/S 17 10 N/S N/S YES 1MM 2 OR 3MM$ 245 MIN GOST 10791 RUSSIA GRADE 1 N/S 880-1080 12 21 30 N/S N/S N/S YES YES 248 MIN FSR FINLAND ER8MOD 530 MIN 860-980 13 50 MIN 15 10 N/S N/S YES 2MM 250 MIN VALDUNES FRANCE R8TUCS 600 MIN 920-1000 13 40 MIN 17 10 N/S N/S YES 1MM 2 OR 3MM$ 265 MIN

IT MET R103 ITALY SUPERLOS 600 MIN 900-1000 16 45 MIN 22 12 10 85 MIN YES 1MM 2 MM 265 MIN

AAR M107 N.AMERICA A N/S N/S N/S N/S N/S N/S N/S N/S YES 1.6MM 255-321



EN13262 EUROPE ER9 580 MIN 900-1050 12 N/S 13 8 N/S N/S YES 1MM 2 OR 3MM$ 255 MIN GOST 10791 RUSSIA GRADE 2 N/S 910-1110 8 14 20 N/S N/S N/S YES YES 255 MIN TB/T 2708 CHINA CL60 N/S 910 MIN 10 14 16 N/S N/S N/S YES YES 265-320 GOST 10791 RUSSIA GRADE 3 N/S 980-1130 8 14 16 N/S N/S N/S YES YES 285 MIN JIS E5402 JAPAN C64 N/S 940-1140 11 N/S 10 N/S N/S N/S NO N/S 277-341

AAR M107 N.AMERICA B N/S N/S N/S N/S N/S N/S N/S N/S YES 1.6MM 300-341

IRSS INDIA R34 N/S N/S N/S N/S 8 N/S N/S N/S NO 3.2MM 300-341

AAR M107 N.AMERICA C N/S N/S N/S N/S N/S N/S N/S N/S YES 1.6MM 321-363


N/S = NOT SPECIFIED * WHEN NO DISTINCT YIELD IS OBSERVED THE 0.2% PROOF STRESS IS REPORTED

UTS = ULTIMATE TENSILE STRENGTH # 2MM LEVEL AS REQUIRED BY RAILWAY GROUP STANDARD GM/RT2466

A = ELONGATION Z = REDUCTION OF AREA $ ACTUAL STANDARD DEFECT LEVEL REQUIRED DEPENDENT UPON DESIGN APPLICATION

MECHANICAL PROPERTIES OF RIM QUOTED ONLY CAT1 IS PREFERRED OPTION FOR TRAINS WITH SPEED ABOVE 125MPH (200KM/H)

Page 18 of 20

Appendix III Old BR grades superseded Table WOSS 612/10

SUPERSESSION OF BR SPECIFICATION MATERIALS BY BS 5892 MATERIALS

The BR Specifications relating to wheelsets are superseded by BS 5892. Where drawings have not yet been amended to show the requirements, the following limits shall apply:-

BS 5892 MATERIAL SPECIFICATION TO BE USED

COMPONENT SUPERSEDED BR SPECIFICATION

BS 5892, Part 1, Grade A1T

Axles

BR 109

BS 5892, Part 2, Grade U

Wheel Centres

BR 107

BS 5892, Part 3, Grade R7E

Monobloc wheels

BR 108, Grade B

BS 5892, Part 3, Grade R8T

Monobloc wheels

BR 108, Grades C (Normalised) and D (Rim Sprayed) and BR 167, Section 4.

BS 5892, Part 3, Grade R8E

Monobloc wheels

BR 108, Grade D (Oil Quenched & Tempered)

BS 5892, Part 4, Grade B6E

Tyres

BR 100, Grade E

BS 5892, Part 4, Grade B5E

Tyres

BR 100, all Grades except E

BS 5892, Part 5

Tyre Retaining Rings

-

BS 5892, Part 6

Wheelset Assembly

BR 163 & 167

Page 19 of 20

of 20

Appendix IV Wheel grade applications

RECOMMENDED GRADES PER RAILWAY NETWORK

APPLICATION SPEED BRAKING WHEEL USA (AAR)

UK (BS)

EUROPE (EN)

INDIA (IRSS)

CHINA (TB/T)

RUSSIA (GOST)

LOAD FREIGHT CARS TREAD B OR C R8T ER7 R19

GRADE 2 OR 3

FREIGHT CARS

WEB-INTEGRAL N/A R7E N/A N/A

GRADE 2 OR 3

FREIGHT CARS D/B WHEEL N/A R8E N/A N/A

GRADE 2 OR 3

LOCOMOTIVES TREAD B OR C R8T ER7 R34 GRADE 2 OR

3

LOCOMOTIVES HEAVY C OR B R8T ER8 R34 GRADE 2 OR

3

PASSENGER HIGH SPEED

TREAD-SEVERE LIGHT L R8T ER6 OR ER7 R19 CL60 GRADE 1


TREAD-SEVERE MODERATE A R8T ER6 OR ER7 R19 CL60 GRADE 1


TREAD-SEVERE HEAVY B R8T ER6 OR ER7 R19 CL60 GRADE 1

PASSENGER TREAD-LIGHT HEAVY C R8T ER6 OR ER7 R19 CL60 GRADE 1 PASSENGER DISC N/A R8T ER7 R19 CL60 GRADE 1 PASSENGER DISC-HEAVY C R8T ER7 R19 CL60 GRADE 1 D/B = DISC BRAKE

Rail Safety & Standards Board Registered Office: Evergreen House 160 Euston Road London NW1 2DX. Registered in England and Wales No. 04655675.

Rail Safety & Standards Board is a not-for-profit company limited by guarantee.

Rail Safety and Standards Board Evergreen House 160 Euston Road London NW1 2DX

Reception Telephone +44 (0)20 7904 7777 Facsimile +44 (0)20 7904 7791

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ABBREVIATIONS AND ACRONYMS1 EXECUTIVE SUMMARY2 BACKGROUND3 APPROACH4 WHEEL STEEL CHARACTERISTICS5 WHEEL STEEL CHEMICAL ANALYSIS DISCUSSION:6 WHEEL STEEL MECHANICAL PROPERTIES DISCUSSION7 SUMMARY8 ACKNOWLEDGEMENTS9 RELATED DOCUMENTS AND SPECIFICATIONSAppendix I Wheel Chemistry TableAppendix II Wheel Mechanical Property TableAppendix III Old BR grades superseded TableAppendix IV Wheel grade applications

Documents

Wheel Steel Handbook