SIST-TS CEN/TS 13103-3:2027

SLOVENSKI STANDARD
01-januar-2027
Železniške naprave - Kolesne dvojice in podstavni vozički - 3. del: Metoda za
načrtovanje osi z zunanjimi ležaji za mestno železnico
Railway applications - Wheelsets and bogies - Part 3: Design method for axles with
external journals for urban rail
Bahnanwendungen - Radsätze und Drehgestelle - Teil 3: Konstruktionsleitfaden für
außengelagerte Radsatzwellen für städtische Schienenbahnen
Applications ferroviaires - Essieux montés et bogies - Partie 3 : Méthode de conception
des essieux-axes avec fusées extérieures pour le rail urbain
Ta slovenski standard je istoveten z: CEN/TS 13103-3:2026
ICS:
45.040 Materiali in deli za železniško Materials and components
tehniko for railway engineering
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TS 13103-3
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
November 2026
TECHNISCHE SPEZIFIKATION
ICS 45.040
English Version
Railway applications - Wheelsets and bogies - Part 3:
Design method for axles with external journals for urban
rail
Applications ferroviaires - Essieux montés et bogies - Bahnanwendungen - Radsätze und Drehgestelle - Teil
Partie 3 : Méthode de conception des essieux-axes avec 3: Konstruktionsleitfaden für außengelagerte
fusées extérieures pour le rail urbain Radsatzwellen für städtische Schienenbahnen
This Technical Specification (CEN/TS) was approved by CEN on 28 September 2026 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

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, Türkiye 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
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 13103-3:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 7
3 Terms and definitions . 7
4 General design process . 7
5 Operational data collection . 8
5.1 Introduction . 8
5.2 Track layout . 8
5.3 Intended axle lifetime mileage . 8
5.4 Relative axle load . 9
5.5 Axle position classification . 9
6 Assessment of the “Operational index” (W) for the application . 9
6.1 General . 9
6.2 Track layout factor W . 9
T
6.3 Lifetime mileage factor W . 10
L
6.4 Axle position factor W . 10
P
6.5 Axle load factor W . 10
A
6.6 Operational index calculation . 10
7 Choice of the design processes . 11
8 Conventional method . 11
9 Conservative conventional method (informative text) . 11
10 Additional assessment. 12
10.1 General . 12
10.2 Determination of the load spectrum . 12
10.3 Scaling of load spectrum to average payload . 13
10.4 Extrapolation of load spectrum to total life . 14
10.5 Miner damage calculation criteria . 14
10.6 Design strategy . 16
10.7 Fatigue damage accumulation design criteria . 17
11 Recording of the design data . 17
Annex A (informative) Design process flowchart . 18
Annex B (informative) Example of calculation of equivalent stress based on measured
load spectrum . 19
Annex C (informative) Technical background used while drafting this technical
specification . 21
C.1 On the general strategy proposed . 21
C.2 On the definition of the passenger masses to consider . 21
C.3 On the choice of the fatigue model . 21
C.4 On the relevance and consistency of the design method with cumulative damage
.............................................................................................................................................................. 22
C.5 On the relevance of the definition of the “Operational index” assessment. 23
C.6 On the definition of the fatigue characteristics . 24
C.7 On the use of the Dm parameter and fatigue model . 26
C.8 Property of the input data . 26
Annex D (informative) Transformation method of the load collective between the
measured cross-section and the critical cross-section . 27
D.1 Principle . 27
D.2 One measurement cross section (MCS) on side of the validation cross section (VCS)
............................................................................................................................................................. 28
D.3 More measurement cross sections (MCS) on side of the validation cross section
(VCS) . 28
D.4 One measurement cross section (MCS) on opposite side of the validation cross
section (VCS) . 28
D.5 More measurement cross sections (MCS) on opposite side of the validation cross
section (VCS) . 28
Bibliography . 30

European foreword
This document (CEN/TS 13103-3:2026) 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.
The informative annexes to this document provide additional guidance that is not mandatory but that
helps to understand or use the document.
The informative annexes may contain optional requirements. For example, a test method that is
optional, or presented as an example, may contain requirements, but it is not necessary to meet these
requirements to be in compliance with the document.
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.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to announce this Technical Specification: 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,
Türkiye and the United Kingdom.
Introduction
EN 13103-1 is used for the design of wheelset axles of railway vehicles. The load assumptions in this
standard refer to mainline vehicles and “normal” European conditions. Operating experience has
shown that the use of EN 13103-1 in urban rail vehicles also results in wheelset axles suitable for
operation. EN 13103-1 remains the basis for the minimum requirements for an axle to fulfill.
EN 13103-1 requires that, before using this European Standard, if there is any doubt as to whether the
railway operating conditions are “normal”, it is necessary to determine whether an additional design
factor has to be applied to the maximum permissible stresses.
have shown that parameters for load assumptions and their
In this context, recent investigations
combination defined in EN 13103-1 may not represent accurately all urban rail operation (network
with low curve radius, payload rate, etc.). Therefore, based on recent research projects in Germany
and other “state-of-the-art” investigations in the European railway sector, additional design methods
have been defined. These methods rely on a different approach than the one defined in EN 13103-1
(infinite lifetime fatigue calculation).
When no extensive technical or operational data are available, refer to EN 13103-1.
When measurements or operational parameters (network characteristics, realistic payload, rolling
stock architecture, wheelset mileage…) are available and show that the conventional method is not
applicable on its own, additional methods can be used.
This document defines the process to assess the operational parameters and their combination in
order to decide if EN 13103-1 is applicable or should be complemented by an additional design
method.
Besides, alternative methods based on cumulative damage fatigue approach are described in the
context of urban rail application.
These methods and processes are described in this document in order to allow the possibility for
wheelset designers to apply it and to collect return of experience for further improvement.
This document was developed with some existing open points such as the weight, the fatigue model
and combination of each parameter in the operating index calculation and even their choice. Annex C
gives an overview of the technical background used to draft the specification.
The aim of this document is therefore to gather information and data in order to close these open
points in a further revision.
Measurements from different R&D projects in Germany shows that the loads prescribed in the EN 13103 series
are different to measured loads. Safe and economical design of railway undercarriages (Volume III) Loads in
local traffic, BMBF German funding, Fkz:119P0061B, July 2005; Development of a methodology for the synthetic
estimation of load collectives of wheelset shafts in local traffic, BMVi German funding, according to research
report FE No. 70.859/2011
1 Scope
This document describes the state of knowledge resulting from Urban Rail experiences regarding the
design of the axle, and further steps to be investigated.
CEN-CENELEC Guide 26 from 1st of June 2013 defines Urban Rail Systems.
This document:
— is applicable for the assessment of new axle designs for urban rail vehicles;
— defines EN 13103-1 as basic calculation method ;
— defines the calculation procedure of an operational index depending on track layout, payload,
mileage, position of the wheelset axle in vehicle. This procedure is based on the examination of
Europe-wide service experiences and calculations made on urban rail wheelset axles running in
Germany ;
— defines the conditions, reflected in this operational index, under which additional assessment
steps may be needed;
— defines these additional assessment steps, including measurements of bending and torsion
moments to derive load collectives representative of normal in-service operating conditions and
the determination of equivalent stresses.
The design methodologies described in this document have been determined for axles of urban rail
rolling stocks running under normal European conditions. If there is any doubt as to whether the
railway operating conditions are normal, these methodologies will be adapted.
This document applies to:
— axles defined in EN 13261:2024;
— axles with outboard bearings;
— powered and non-powered axles;
— solid and hollow axles;
— all track gauges .
This document does not apply to tilting vehicles.
The calculation of wheelset axles for special applications (e.g. tamping/lining/levelling machines) may
be made according to this document only for the load cases of free-running and running in train
formation. This document does not apply to workload cases. They are calculated separately.

When no sufficient technical or operational data is available, EN 13103-1 can be used.
This Technical Specification reflects the state of knowledge resulting from Urban Rail experiences regarding the design of the axle, built-
on by subcommittee DIN specially based for this Technical Specification.
If the gauge is not standard, certain formulae need to be adapted, e.g. according to EN 13103-1:2017+A1:2022.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 13103-1:2017+A1:2022, Railway applications - Wheelsets and bogies - Part 1: Design method for
axles with external journals
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
• ISO Online browsing platform: available at https://www.iso.org/obp
• IEC Electropedia: available at https://www.electropedia.org/
3.1
solidity
parameter characterising the interaction of the network with regard to the rolling stock, given the
guiding forces generated when passing through curves with small radii
3.2
unidirectional vehicle
vehicle which guiding wheelset never changes in normal operation, e.g. vehicles with only one leading
driver cab always travelling in the same direction
3.3
bidirectional vehicle
vehicle which guiding wheelset changes depending on the travelling direction, e.g. vehicles with two
opposite driver cabs such as metros or EMU’s
3.4
mean service conditions
normal operating conditions that are most likely to be encountered in service excluding all exceptional
or particular conditions
4 General design process
The major phases for the design of an axle for urban rail application are:
a) Collection of the operational data (network characteristics, expected mileage of the axle…)
b) Assessment of the “Operational index” (W) for the application
c) Calculation in accordance with EN 13103-1:2017+A1:2022
d) Assessment of load spectra representative of normal in-service operating conditions to verify the
load assumptions
e) Damage accumulation fatigue assessment
Step d) and e) are only carried out under the conditions defined in chapter 7.
The design process should follow the flow chart defined in Annex A.
5 Operational data collection
5.1 Introduction
The first step when designing an axle for urban rail application is to collect the operational data
enabling the calculation of an “operational index”. Part of this data, especially the track layout, is under
the responsibility of the infrastructure manager.
In case the infrastructure manager is unable to provide this data, measurements should be made to
assess them, or a conservative assumption should be made (W > 1) and validated during on-track
measurements.
5.2 Track layout
In urban rail networks there is a significantly different distribution of curve radii, compared to heavy
rail networks, with high percentage of low curve radii.
To classify a network, data consisting of the distribution of curve radii and the share in the total length
L of the track of the network are necessary. The data should be recorded according to Table 1 classes.
Table 1 — Track layout data collection
Share of the classes in the
Length of the
whole network
Classes of radii radii of the class
L [m]
R,i h = L /L [-]
i R,i
1000 < R
500 < R ≤ 1000
250 < R ≤ 500
100 < R ≤ 250
50 < R ≤ 100
25 < R ≤ 50
R ≤ 25
Key
i number of class of Radii
L [m] sum of the track length in each radii class in the network
R,i
h = L /L share of the track length in each class in the network
i R,i
L [m] whole length of track in the network
The data to record shall represent the nominal operational service conditions of the vehicles to run on
the intended network.
5.3 Intended axle lifetime mileage
The intended mileage during service life should be defined in the technical specification.
This parameter, expressed in km, is defined as M .
service
5.4 Relative axle load
The relative axle load is calculated with the axle load according to the mean operational loading and
the maximum axle load according to EN 13103-1:2017+A1:2022:
2P
mean
Q =
rel
2P
Where
P Mean operational loading: Half the vertical force per wheelset on the rail in mean service
mean
conditions
P Half the vertical force per wheelset on the rail according to EN 13103-1:2017+A1:2022
Q Relative axle load
rel
5.5 Axle position classification
The axles should be classed in one of the three classes below:
— 100 % guiding axle: first axle of a bogie (in the running direction) of a unidirectional vehicle;
— 50 % guiding axle: all the axles of a bidirectional vehicle;
— 0 % guiding axle: second axle of a bogie (in the running direction) of a unidirectional vehicle.
6 Assessment of the “Operational index” (W) for the application
6.1 General
Using the data identified in Clause 5, the following assessment parameters shall be determined.
6.2 Track layout factor WT
The identified partition of the radii classes (see 5.1) shall be combined with the relative guiding forces
according to Table 2:
Table 2 — Relative guiding forces assessment table
Relative guiding forces
i Radii classes L [m] h [-]
R,i i
Y [-]
rel,i
1000 < R   0,29
500 < R ≤ 1000   0,39
250 < R ≤ 500   0,51
100 < R ≤ 250   0,65
50 < R ≤ 100   0,8
R ≤ 50   1,0
NOTE The relative guiding forces assessments are recorded in [2].
To classify the network, the solidity of the track layout shall be calculated, using the following formula:
j
k
k
v h× Y
∑ i rel,i
i=1
Where
v solidity
h partition of the classes of radii
i
Y Relative Y-force according to Table 2
rel
i number of classes
k SN curve exponent k = 7
With the calculated solidity, the weighting factor of the track layout shall be determined:
W = max (1,7857 v ; 0,52)
T
6.3 Lifetime mileage factor WL
With the identified mileage M [km] from 5.3, the lifetime mileage factor is calculated according to
Service
the following formula:
−7
W = 1,667 × 10 × M
L Service
6.4 Axle position factor WP
With the identified axle position classification from 5.5, the axle position factor W is defined according
P
to Table 3:
Table 3 — Axle position factor definition
Axle position factor,
Axle position classification
W
P
100 % guiding axle: first axle of a bogie (in the
2,0
running direction) of a unidirectional vehicle
50 % guiding axle: all the axles of a
1,0
bidirectional vehicle
0 % guiding axle: second axle of a bogie (in the 0,2
running direction) of a unidirectional vehicle
6.5 Axle load factor WA
With relative axle load parameter assessed according to 5.4, the axle load factor is calculated according
to the following formula:
7,735Q
rel
We= 0,001
A
6.6 Operational index calculation
The operational index factor is calculated by combining the track layout factor, lifetime mileage factor,
the axle position factor and the axle load factor according to the following formula:
WW ++  W  + W
T L P A
W =
=
7 Choice of the design processes
Depending on the result of the operational index calculation, the process (according to Annex A) can
follow three different paths:
1) If W ≤ 1, then the conventional method for axle design according to EN 13103-1:2017+A1:2022
should be applied (see Clause 8)
2) If W > 1, the conventional method for axle design according to EN 13103-1:2017+A1:2022 should
be completed with an additional assessment (see Clause 10)
3) If W is comparable (or lower) and each of the weighing factor are individually comparable
(qualitative assessment) to an existing network/operational conditions, used under the same
rolling stock, with a positive return of experience and same maintenance scheme, then the axle
does not need to be reassessed and is considered as safe for operation in the same conditions.
NOTE To this day the exact weight/combination of each factor in the operational index calculation is
unknown, therefore, in a further revision, when this weight/combination is known, a single comparison of the
W index will be sufficient to compare two different operating conditions.
Whatever the design method used, for a new rolling stock, there should be no exported Safety Related
Application Conditions (SRACs) on operating conditions and/or maintenance. Such SRACs could be
the limitation of passengers in a coach, limitation of speed, additional NDT’s on the axles etc. which
are not acceptable when designing a new axle.
8 Conventional method
The conventional method for axle design is derived from the EN 13103-1:2017+A1:2022 standard for
the design of heavy rail wheelsets.
The main parameter to adapt when carrying out the conventional axle design method is the mass to
be used for the calculation of the forces to apply on the axle.
Table 3 of EN 13103-1:2017+A1:2022 is then to be adapted according to Table 4.
Table 4 — Masses to take into account for urban rail vehicles
Type of rolling stock Mass (m + m )
1 2
Urban rail passenger vehicle Design mass in working order is defined in EN 15663.
Normal design payload is defined in EN 15663 on which the
standing passengers shall be:
2 2
— 420 kg/m (6 passengers per m ) in standing areas
(corridors and platforms)
The payloads to be taken into account to determine the mass of the suburban vehicles broadly reflect
the normal operating conditions (see Annex C for the explanation).
9 Conservative conventional method (informative text)
When developing this technical specification, considering the fact that an additional method (chapter
10) to the conventional one (EN 13103-1:2017+A1:2022) requires much data and specific know-how,
an alternative method would be to use a conservative design process.
In such process, the forces, especially the Y-forces, defined in EN 13103-1:2017+A1:2022, depending
on the curve distribution and radius, could be scaled to ensure a safe design.
It should be emphasized that such a method would not be optimized at all and would lead to heavier
and “over-designed” wheelsets.
While drafting this document such a method could not be defined but could be introduced in a further
revision of this technical specification.
10 Additional assessment
10.1 General
When it has been shown that an additional assessment to the conventional method is needed, the
following steps should be followed (see also the flowchart in Annex A).
They are principally derived from CEN/TR 17469 [1].
The cumulative damage assessment procedure uses a load spectrum determined by strain gauges on
the axle under running conditions representative of the ones for which the axle has to be assessed: the
axle is installed in the actual vehicle in service on the actual rail network.
10.2 Determination of the load spectrum
The measurements shall be done on the first axle of the trainset as it should be subjected to higher
lateral loads; other axles in the trainset may have to be measured in case, for instance, if the static load
is much higher or the axle design is different.
Strain gauges shall be installed on the axle to measure strains in order to process the bending and
torsional stresses, at least at the body section near the one which results to be the most critical in the
EN 13103-1:2017+A1:2022 calculation method. In defining the actual section for the strain gauge
installation, choosing a section that is not influenced by stress concentration is preferable. In the case
of a typical seat-body transition, 40 mm long, it means installing the strain gauge at about 60-80 mm
from the edge. A FEM model of the wheelset can be used to determine the ratio (k ) between the
t
maximum strain in the transition and the strain in the measured section; this ratio will then be used
to correct the measured strain.
In case the measurement
...