The University of Sheffield and LBFoster

Driving Innovation in Track Components and Friction Management

Dr Roger LewisDepartment of Mechanical Engineering

Some Current Railway

Engineering Projects

Overhead Line Wear(Network Rail)

Rail Joint Innovation(LBFoster)

Traction Gels (LBFoster)

Top of Rail FMs & Adhesion Measurement (LBFoster )

Wheel Wear Prediction (Alstom)

TGamma vs wear, Wear Transitions and Mapping(RSSB, KTH)

Wheel/Rail Contact Measurement

0.00 0.05 0.10 0.15 0.20400

600

800

1000

1200

CATASTROPHIC

MILD

Sliding Speed (m/s)

Con

tact

Pre

ssur

e (M

Pa)

437.5 -- 500.0 375.0 -- 437.5 312.5 -- 375.0 250.0 -- 312.5 187.5 -- 250.0 125.0 -- 187.5 62.50 -- 125.0 0 -- 62.50

Con

tact

Pre

ssur

e (M

Pa)

20 kN 40 kN

60 kN 80 kN

-475

-470

-465

-460

-455

-450

-445

-440

-820 -800 -780 -760 -740 -720 -700 -680Y [mm]

Z [

mm

]

New Profile

Vehicle 1 - Left Wheel

Vehicle 2 - Left Wheel

Wheel/Rail Isolation(LU, LBFoster)

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0

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0 20 40 60 80 100

Time (secs)

Vo

ltag

e A

cro

ss D

iscs

(V

)

1

2

3

Rail Grinding (Network Rail)

11/04/23 © The University of Sheffield

LBFoster Rail Products•Bonded insulated joints

•Friction management

•Wayside data collection

•Direct fixation fasteners

•Railcar products

•Power rail systems

•Coverboards

•Track components

Sheffield

How we work together

11/04/23 © The University of Sheffield

Consultancy Short term projects Friction management – test development and new product benchmarking

Research PhD Wheel/rail contact – effect of third-body materials

Knowledge Transfer

Knowledge Transfer Partnership (KTP) (www.ktponline.org.uk)

IBJ innovation

Commercial Testing

Short term projects Track components

Today’s focus

11/04/23 © The University of Sheffield

Insulated joints: Areas of interest

Shear strength of epoxy glue layer

Effect of decarburisation on fishplates

Endpost lipping problem

Fatigue performance of whole joint

Condition Monitoring

11/04/23 © The University of Sheffield

Fishplate Decarburisation• Decarburisation could affect

the fatigue properties and weaken the fishplate

• Testing will cyclically load steel fishplates with varying amounts of surface decarburisation

• Effects of decarburisation on fishplates will be determined and methods for enhancing fatigue performance

Test Base

Fishplate Support Blocks

Cyclic Load

Decarb layer in steel

fishplates

11/04/23 © The University of Sheffield

Endpost Lipping• Plastic deformation of the rail

over the endpost causes electrical insulation failure

• Twin-disc testing has attempted to model this behaviour

• Testing will lead to understanding of this type of failure and the creation of techniques to reduce the problem and premature failure

11/04/23 © The University of Sheffield

Glued joint shear testing• A test to establish the

difference in properties between various glues and insulating liner materials

• Glued insulated joints are sectioned and the rail is pushed through the joint

• Aim to introduce new and improved insulating materials to the market with better shear properties

Test Base

Joint Section

Sheared Fishplate

Load Cell

11/04/23 © The University of Sheffield

Full-scale IBJ testing• Standard and bespoke fatigue test

apparatus currently used to conduct standard tests to verify joint performance (aim to not fail)

• Aim now is to develop full life cycle testing (by changing the support set-up and the loads applied to the insulated joint)

• This test can then be used to assess impact on life of design and material changes

11/04/23 © The University of Sheffield

Condition Monitoring

• Development of an ultrasonic based system to monitor key interfaces underway

• Technique proven on simple bolted interfaces

Transducers Mounted on Under-side

Cyclic Loading

Friction Management• Extensive adhesion tests carried out with and

without contaminants (oil, water, leaves etc.)

• Traction gels for adhesion enhancement (leaf layers generated in twin disc tests and gels applied)

• Top of rail FMs (noise and vibration mitigation)

• Effect of stick lubricants on wheel/rail isolation

• Third-body layers and oxides

• Adhesion measurement

11/04/23 © The University of Sheffield

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Benefits of the collaboration

• Access to University expertise and test facilities

• Gearing for R&D projects – either through University or external sources

• Short term problem solving

• Long term approach possible

11/04/23 © The University of Sheffield