CEN/TR 17792:2022

SLOVENSKI STANDARD
01-april-2022
Železniške naprave - Geometrijski parametri stika kolo-tirnica - Tehnično poročilo
in temeljne informacije o standardu EN 15302
Railway Applications - Wheel-rail contact geometry parameters - Technical report and
background information about EN 15302
Bahnanwendungen - Rad-Schiene-Berührgeometrieparameter - Technischer Bericht und
Hintergrundinformationen zur EN 15302
Applications ferroviaires - Paramètres géométriques du contact roue-rail - Rapport
technique et informations générales sur l’EN 15302:2021
Ta slovenski standard je istoveten z: CEN/TR 17792:2022
ICS:
45.060.01 Železniška vozila na splošno Railway rolling stock in
general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TR 17792
TECHNICAL REPORT
RAPPORT TECHNIQUE
February 2022
TECHNISCHER BERICHT
ICS 17.040.20; 45.060.01
English Version
Railway Applications - Wheel-rail contact geometry
parameters - Technical report and background
information about EN 15302
Applications ferroviaires - Paramètres géométriques Bahnanwendungen - Rad-Schiene-
du contact roue-rail - Rapport technique et Berührgeometrieparameter - Technischer Bericht und
informations générales sur l'EN 15302:2021 Hintergrundinformationen zur EN 15302

This Technical Report was approved by CEN on 10 January 2022. It has been drawn up by the Technical Committee CEN/TC 256.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 17792:2022 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Overview of the most important changes made to EN 15302 . 6
4.1 List of main changes . 6
4.2 Additional wheel-rail contact geometry parameters . 6
4.2.1 Rolling radii coefficient . 6
4.2.2 Nonlinearity parameter . 6
4.3 Methods for evaluation of equivalent conicity . 7
4.4 Assessment of the smoothing process . 7
4.5 New assessment of the complete process . 8
5 Technical background to and justification of changes in the revised EN 15302 . 8
5.1 Equivalent conicity . 8
5.1.1 Review of equivalent conicity results obtained with different software tools . 8
5.1.2 Comparison with multibody system simulation results .11
5.1.3 Influence of discretisation step size of the rolling radius difference function .14
5.2 Rolling radii coefficient .15
5.2.1 Background .15
5.2.2 Current method .17
5.3 Nonlinearity parameter .20
5.4 Calculation of equivalent conicity by two-step integration .22
5.5 Calculation of equivalent conicity by direct integration of the kinematic equation of
motion .23
5.6 Calculation of equivalent conicity by harmonic linearization .23
5.7 Updated reference profiles and results based on analytical solutions .25
5.8 Revised assessment of the smoothing process .27
5.9 Example for uncertainty assessment of the complete process .27
5.10 Influence of simplifications .31
5.10.1 General .31
5.10.2 Wheelset roll movement (rotation around the longitudinal axis) .31
5.10.3 Contact elasticity of wheel and rail .36
6 Guidance for the application of the wheel-rail contact parameters given in EN 15302
....................................................................................................................................................................39
6.1 Fields of application – Overview .39
6.2 General guidelines .39
6.3 Selection of appropriate reference profiles for assessment of rail head profiles
and/or wheel profiles .40
6.3.1 General .40
6.3.2 British Rail Research Survey .40
6.3.3 Reference profiles in the DynoTRAIN project.40
6.3.4 Assessment of design wheel profiles and design rail profiles .42
6.4 Development of equivalent conicity of wheelsets over mileage .43
6.5 Assessment of the contact geometry of a line .45
6.5.1 Methods for determining averaged contact geometry parameters .45
6.5.2 Assessment of a line for different wheel profiles . 46
6.6 Rolling radii coefficient and radial steering index . 48
6.7 Nonlinearity parameter . 51
6.8 Equivalent conicity in wheel-rail maintenance and interface with TSIs . 53
6.8.1 General . 53
6.8.2 Equivalent conicity that a vehicle was designed and tested for . 53
6.8.3 Equivalent conicity as parameter in wheel profile maintenance regimes . 53
6.9 Clarification of wheel-rail contact test conditions according to EN 14363 . 54
6.10 Application of Contact angle parameter and Roll angle parameter . 55
7 Alternative contact parameters not handled in the standard . 55
7.1 Difference of contact angles and gravitational stiffness . 55
7.2 Contact Concentration Index . 56
8 Approximation of equivalent conicity by simple alternative methods. 60
8.1 Background . 60
8.2 British Rail Research investigations . 60
8.2.1 Initial BRR work in 1980s. 60
8.2.2 BRR further work in 1990s . 63
8.3 Investigations on Quick conicity using DynoTRAIN data . 66
8.3.1 DynoTRAIN project data collection . 66
8.3.2 Investigations on rail data . 67
8.3.3 Investigations on wheel data . 73
8.3.4 Combined assessment – track and wheelset . 75
8.3.5 Next Steps . 75
8.4 Ongoing development of Gradient Index Profile (GIP) . 76
8.4.1 Definition of GIP . 76
8.4.2 Comparison between equivalent conicity and GIP combined . 77
9 Development and usage of the so called conicity maps . 77
10 Plausibility check of measured profiles and elimination of outliers . 79
10.1 Introduction . 79
10.2 Profile area to be covered. 79
10.3 Spacing of points on the profile . 79
10.4 Elimination of outliers . 80
11 Examples for validation of profile measuring systems . 81
11.1 General . 81
11.2 Evaluations of rail profile measuring systems . 81
11.3 Evaluations of ground-based wheel profile measuring systems . 83
12 Effect of wheel diameter differences on the running behaviour . 84
Bibliography . 85
European foreword
This document (CEN/TR 17792:2022) has been prepared by Technical Committee CEN/TC 256 “Railway
applications”, the secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a Standardization Request given to CEN by the European
Commission and the European Free Trade Association.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
1 Scope
This document provides background information regarding the changes from EN 15302:2008+A1:2010
to the revised version dated 2021, including the reasons for decisions and additional explanation and
guidance that is not appropriate in the standard.
The range of equivalent conicity results obtained with different software tools is described. The
additional wheel-rail contact parameters, rolling radii coefficient and nonlinearity parameter, are
expl
...