Railway applications - Wheelsets and bogies - Product requirements for cast wheels

This European Standard specifies the characteristics of cast railway wheels for use on European networks.
Two steel grades, C ER7 and C ER8, are defined in this standard. For tread-braked wheels; only C ER7 is
used.
This standard is applicable to cast wheels which have a chilled rim. The standard is only applicable to cast
wheels that have satisfied the technical approval procedure according to FprEN 13979-2.
This standard applies only to wheels used in freight wagon applications for speeds up to and including
120 km/h.

Bahnanwendungen - Radsätze und Drehgestelle - Produktanforderungen für Gussräder

Diese Technische Spezifikation legt die Merkmale von gegossenen Eisenbahnrädern fest, die auf europäischen Streckennetzen verwendet werden sollen.
In dieser Technischen Spezifikation werden zwei Stahlgüten, CER7 und CER8 definiert. Für über die Laufflächen gebremste Räder wird nur CER7 verwendet.
Diese Technische Spezifikation ist auf Gussräder mit gehärteten Radreifen anwendbar. Diese Technische Spezifikation ist nur auf Gussräder anwendbar, die das technische Genehmigungsverfahren nach CEN/TS 13979-2 erfüllt haben.
Diese Technische Spezifikation gilt nur für Räder, die in Güterwagenanwendungen für Geschwindigkeiten bis zu einschließlich 120 km/h verwendet werden.

Applications ferroviaires - Essieux montés et bogies - Exigences pour roues en acier moulé

La présente Norme européenne spécifie les caractéristiques des roues en acier moulé équipant les véhicules ferroviaires utilisés sur les réseaux européens.
La présente norme définit deux nuances d’acier, C ER7 et C ER8. Pour les roues équipées de freins à semelles, seule la nuance C ER7 est utilisée.
La présente norme s’applique aux roues en acier moulé munies d’une jante traitée en surface. Elle s’applique uniquement aux roues en acier moulé ayant satisfait à la procédure d’homologation technique selon le FprEN 13979-2.
La présente norme s’applique uniquement aux roues utilisées dans les applications des wagons fret à des vitesses inférieures ou égales à 120 km/h.

Železniške naprave - Kolesne dvojice in podstavni vozički - Zahtevane lastnosti za lita kolesa

Ta evropski standard določa značilnosti litih železniških koles za uporabo v evropskih omrežjih.
V tem standardu sta določena dva razreda jekla, C ER7 in C ER8. Za kolesa s profilno zavoro se uporablja le C ER7.
Ta standard velja za lita kolesa z ohlajenim platiščem. Standard velja le za lita kolesa, ki so prestala postopek tehnične odobritve v skladu s FprEN 13979-2.
Ta standard velja le za kolesa, ki se uporabljajo za aplikacije tovornih vagonov za hitrosti do vključno 120 km/h.

General Information

Status
Published
Publication Date
11-Oct-2011
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
20-Sep-2011
Due Date
25-Nov-2011
Completion Date
12-Oct-2011

Buy Standard

Technical specification
SIST-TS CEN/TS 15718:2011
English language
42 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)

SLOVENSKI STANDARD
SIST-TS CEN/TS 15718:2011
01-november-2011

äHOH]QLãNHQDSUDYH.ROHVQHGYRMLFHLQSRGVWDYQLYR]LþNL=DKWHYDQHODVWQRVWL]D

OLWDNROHVD

Railway applications - Wheelsets and bogies - Product requirements for cast wheels

Bahnanwendungen - Radsätze und Drehgestelle - Produktanforderungen für Gussräder

Applications ferroviaires - Essieux montés et bogies - Exigences pour roues en acier

moulé
Ta slovenski standard je istoveten z: CEN/TS 15718:2011
ICS:
45.040 Materiali in deli za železniško Materials and components
tehniko for railway engineering
SIST-TS CEN/TS 15718:2011 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST-TS CEN/TS 15718:2011
---------------------- Page: 2 ----------------------
SIST-TS CEN/TS 15718:2011
TECHNICAL SPECIFICATION
CEN/TS 15718
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
September 2011
ICS 45.040
English Version
Railway applications - Wheelsets and bogies - Product
requirements for cast wheels

Applications ferroviaires - Essieux montés et bogies - Bahnanwendungen - Radsätze und Drehgestelle -

Exigences pour roues en acier moulé Produktanforderungen für Gussräder

This Technical Specification (CEN/TS) was approved by CEN on 3 January 2011 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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2011 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 15718:2011: E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST-TS CEN/TS 15718:2011
CEN/TS 15718:2011 (E)
Contents Page

Forew ord ..............................................................................................................................................................4

Introduction .........................................................................................................................................................5

1 Scope ......................................................................................................................................................6

2 Normative references ............................................................................................................................6

3 Product definition ..................................................................................................................................7

3.1 Chemical composition ..........................................................................................................................7

3.1.1 Values to be achieved ...........................................................................................................................7

3.1.2 Location of the sample ..........................................................................................................................7

3.1.3 Chemical analysis ..................................................................................................................................7

3.2 Mechanical characteristics ...................................................................................................................7

3.2.1 Tensile test characteristics ...................................................................................................................7

3.2.2 Hardness characteristics in the rim .....................................................................................................9

3.2.3 Impact test characteristics .................................................................................................................10

3.2.4 Fatigue characteristics ........................................................................................................................10

3.2.5 Fracture toughness characteristics of the rim .................................................................................11

3.3 Heat treatment homogeneity ..............................................................................................................12

3.3.1 Location of measurement ...................................................................................................................12

3.3.2 Values to be achieved .........................................................................................................................12

3.3.3 Test method ..........................................................................................................................................12

3.4 Metallurgical structure ........................................................................................................................12

3.5 Material cleanliness .............................................................................................................................12

3.5.1 Micrographic cleanliness ....................................................................................................................12

3.5.2 Internal integrity ...................................................................................................................................13

3.6 Residual stresses ................................................................................................................................16

3.6.1 General ..................................................................................................................................................16

3.6.2 Values to be achieved .........................................................................................................................16

3.6.3 Test piece .............................................................................................................................................17

3.6.4 Measurement methods ........................................................................................................................17

3.7 Surface characteristics .......................................................................................................................17

3.7.1 Surface appearance .............................................................................................................................17

3.7.2 Surface integrity ...................................................................................................................................17

3.8 Geometric tolerances ..........................................................................................................................18

3.9 Static imbalance ...................................................................................................................................20

3.10 Shot peening - Requirements .............................................................................................................20

3.10.1 General ..................................................................................................................................................20

3.10.2 Values to be achieved .........................................................................................................................21

3.10.3 Measurement method ..........................................................................................................................21

3.11 Protection against corrosion ..............................................................................................................21

3.12 Wheel maintenance capacity ..............................................................................................................21

3.13 Manufacture’s markings .....................................................................................................................21

Annex A (normative) Hydrogen control at the point of steel melt for monobloc wheels ..........................23

A.1 Sampling ...............................................................................................................................................23

A.2 Analysis methods ................................................................................................................................23

A.3 Operating precautions ........................................................................................................................23

Annex B (informative) Example of a test method for the determination of fatigue characteristics .........24

B.1 Test piece .............................................................................................................................................24

B.2 Test rig ..................................................................................................................................................24

B.3 Test monitoring ....................................................................................................................................24

B.4 Analysis of results ...............................................................................................................................24

---------------------- Page: 4 ----------------------
SIST-TS CEN/TS 15718:2011
CEN/TS 15718:2011 (E)

Annex C (informative) Strain gauge method for determining the variation of circumferential

residual stresses located deep under the tread (destructive method) ............................................. 25

C.1 Principle ............................................................................................................................................... 25

C.2 Procedure ............................................................................................................................................. 25

C.2.1 Fitting of a rim cross section with strain gauges prior to wheel cutting ....................................... 25

C.2.2 Execution of cutting ............................................................................................................................ 25

C.2.3 Operations to be executed during cutting ........................................................................................ 26

C.3 Expression of results .......................................................................................................................... 26

C.3.1 Calculation of the variation of the circumferential residual stress located deep under the

tread ...................................................................................................................................................... 26

C.3.2 Calculation of the variation of the circumferential stress created by cutting operation 1 .......... 26

C.3.3 Calculation of the variation of the circumferential stress created by cutting operation 2 .......... 27

C.3.4 Calculation of the variation of the circumferential stress created by cutting operation 3 .......... 27

C.3.5 Final diagram representing the variation of the circumferential stress located deep under

the tread ............................................................................................................................................... 27

Annex D (informative) Product qualification .................................................................................................. 31

D.1 General ................................................................................................................................................. 31

D.2 Requirements ....................................................................................................................................... 31

D.2.1 Requirements for the producer .......................................................................................................... 31

D.2.2 Requirements for the product ............................................................................................................ 32

D.3 Qualification procedure ...................................................................................................................... 32

D.3.1 General ................................................................................................................................................. 32

D.3.2 Documentation required ..................................................................................................................... 32

D.3.3 Evaluation of manufacturing equipment and of the production processes ................................. 33

D.3.4 Laboratory tests .................................................................................................................................. 33

D.3.5 Testing of wheels ................................................................................................................................ 34

D.4 Qualification certificate ....................................................................................................................... 34

D.4.1 Condition of the validity ...................................................................................................................... 34

D.4.2 Modification and extension ................................................................................................................ 34

D.4.3 Transference ........................................................................................................................................ 35

D.4.4 Lapsed certificate ................................................................................................................................ 35

D.4.5 Cancellation ......................................................................................................................................... 35

D.5 Qualification documents ..................................................................................................................... 35

Annex E (informative) Product delivery .......................................................................................................... 36

E.1 General ................................................................................................................................................. 36

E.2 Delivery condition ............................................................................................................................... 36

E.3 Controls on each wheel ...................................................................................................................... 37

E.4 Batch control ....................................................................................................................................... 37

E.4.1 Controls ................................................................................................................................................ 37

E.4.2 Uniformity of batches by measurement of rim hardness ................................................................ 38

E.4.3 Orientation of residual stresses on rim chilled wheels ................................................................... 39

E.4.4 Shot peening ........................................................................................................................................ 39

E.4.5 Visual inspection ................................................................................................................................. 40

E.4.6 Quality plan .......................................................................................................................................... 40

E.5 Allowable rectification ........................................................................................................................ 41

Bibliography ...................................................................................................................................................... 42

---------------------- Page: 5 ----------------------
SIST-TS CEN/TS 15718:2011
CEN/TS 15718:2011 (E)
Foreword

This document (CEN/TS 15718:2011) has been prepared by Technical Committee CEN/TC 256 “Railway

applications”, the secretariat of which is held by DIN.

Your attention is drawn to the fact that certain elements in this document may be subject to intellectual

property or similar rights. CEN and/or CENELEC cannot be held responsible for not identifying such property

rights and providing a warning of their existence.

This document has been prepared under a mandate given to CEN by the European Commission and the

European Free Trade Association, and supports essential requirements of EU Directive 2008/57/CE.

According to CEN/CENELEC Internal Regulations, the national standards organizations of the following

countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Cyprus, Croatia, the

Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Iceland, Italy,

Latvia, Lithuania, Luxembourg, Malta, Norway, the Netherlands, Poland, Portugal, Romania, Slovakia,

Slovenia, Spain, Sweden, Switzerland and the United Kingdom.
---------------------- Page: 6 ----------------------
SIST-TS CEN/TS 15718:2011
CEN/TS 15718:2011 (E)
Introduction

Prior to the publication of this Technical Specification, the only European Standard available to define quality

requirements for monobloc wheels was EN 13262, which applies only to forged and rolled wheels. Forging

and rolling was the only authorized process to be used by the UIC regulation that was applicable in the recent

past for European countries.

Cast wheels are commonly used by AAR networks and have been introduced into Europe on some

applications for freight wagons. As a reference document, this standard defines the product requirements of a

monobloc cast wheel. In order for a cast wheel to maintain the same level of safety as for a forged and rolled

wheel, for the product characteristics, the main content of this document is derived from EN 13262.

This standard addresses a complete definition of the product and delivery procedures for cast wheels by:

a) defining all the wheel characteristics;

NOTE 1 These are either verified during the qualification or for the delivery of the product (see Clause 3).

b) defining qualification procedures (see Annex D);
c) defining delivery conditions (see Annex E).
NOTE 2 A choice is given to the supplier, of either:

1) a traditional delivery procedure with a control by batch sampling as in existing documents (see E.4) or;

2) delivery procedure using quality assurance concepts (see E.4.6).
---------------------- Page: 7 ----------------------
SIST-TS CEN/TS 15718:2011
CEN/TS 15718:2011 (E)
1 Scope

This technical standard specifies the characteristics of cast railway wheels for use on European networks.

Two steel grades, C ER7 and C ER8, are defined in this Technical Specification. For tread-braked wheels;

only C ER7 is used.

This Technical Specification is applicable to cast wheels which have a chilled rim. The standard is only

applicable to cast wheels that have satisfied the technical approval procedure according to CEN/TS 13979-2.

This Technical Specification applies only to wheels used in freight wagon applications for speeds up to and

including 120 km/h.
2 Normative references

The following referenced documents are indispensable for the application of this document. For dated

references, only the edition cited applies. For undated references, the latest edition of the referenced

document (including any amendments) applies.

EN 13262, Railway applications — Wheelsets and bogies — Wheels — Product requirements

EN 10045-1, Metallic materials — Charpy impact test — Part 1: Test method

EN ISO 148-1, Metallic materials - Charpy pendulum impact test - Part 1: Test method (ISO 148-1:2009)

EN ISO 6506-1, Metallic materials — Brinell hardness test — Part 1: Test method (ISO 6506-1:2005)

EN ISO 6892-1, Metallic materials ― Tensile testing. Part 1: Method of test at room temperature

(ISO 6298-1:2009).

ISO 1101, Geometrical Product Specifications (GPS) – Geometrical tolerancing -- Tolerances of form,

orientation, location and run-out.
ISO 5948:1994, Railway rolling stock material — Ultrasonic acceptance testing

ISO 6933:1986, Railway rolling stock material — Magnetic particle acceptance testing

ISO/TR 9769 , Steel and iron — Review of available methods of analysis

ISO 14284, Steel and iron — Sampling and preparation of samples for the determination of chemical

composition

ASTM E 399-90:1990, Test method for plane-strain fracture toughness of metallic materials

ASTM E1245, Standard Practice for Determining the Inclusion or Second-Phase Constituent Content of

Metals by Automatic Image Analysis
SAE J827, High-carbon cast-steel shot
SAE J442, Test strip, holder and gage for shot peening
SAE J443, Procedures for using standard shot peening test strip
1) See also CEN report CR 10261:1995.
---------------------- Page: 8 ----------------------
SIST-TS CEN/TS 15718:2011
CEN/TS 15718:2011 (E)
SAE J444, Cast shot and grit size specifications for peening and cleaning
3 Product definition

When the characteristics of the wheel vary as a result of the casting process, the test pieces shall be taken

from the worst-case location. The worst-case location has to be defined during the product qualification

process by means of comparative tests in different parts of the wheel (feeder head area, outside feeder head

area, intermediate). These defined locations are valid for a given manufacturing process and used for the

ongoing production. In the case of a process change, these locations will have to be defined again.

3.1 Chemical composition
3.1.1 Values to be achieved

The maximum percentage contents of the various elements contained within cast wheels shall be as given in

Table 1.
Table 1 — Maximum content of various elements within cast wheels
Steel Maximum content
grade
c a a, b c
C Si Mn P S Cr Cu Mo Ni V Cr +
Mo +
CER7 0,52 0,6 0,80 0,020 0,02 0,30 0,30 0,12 0,30 0,06 0,52
CER8 0,56 0,6 0,80 0,020 0,02 0,30 0,30 0,12 0,30 0,06 0,52

NOTE For special applications, variations within the maximum limit of these values may be agreed.

A maximum content of 0,025 % may be agreed at the time of enquiry or order.

A minimum sulfur content may be agreed at the time of enquiry and at the time of order in order to

safeguard against hydrogen cracking.

These values exceed those in EN 13262. It shall be ensured that use of these values does not

adversely affect the metallurgical structure of the wheel.
3.1.2 Location of the sample

The sample used for determining the chemical composition shall be taken 15 mm below the tread at its

nominal diameter.
3.1.3 Chemical analysis

The chemical composition analysis shall be performed according to methods and definitions that are

described in ISO/TR 9769.
3.2 Mechanical characteristics
3.2.1 Tensile test characteristics
3.2.1.1 Values to be achieved

Cast wheels shall have rim and web characteristics of at least the values given in Table 2.

---------------------- Page: 9 ----------------------
SIST-TS CEN/TS 15718:2011
CEN/TS 15718:2011 (E)
Table 2 — Minimum tensile test values of the rim and web
Steel grade Rim Web
a b
R ≥ R A ≥ R reduction ≥ A ≥
eH 5 m 5
2 2 2
N/mm N/mm % N/mm %
CER7 ≥ 520 820/940 ≥ 14 ≥ 110 ≥ 16
CER8 ≥ 540 860/980 ≥ 13 = 120 ≥ 16

If no distinctive yield strength is present, the proof stress R shall be determined.

p0,2
Reduction of tensile strength as compared to that of the rim on the same wheel.
3.2.1.2 Location of test pieces

Test pieces shall be taken from the rim and the web of the wheel, as indicated in Figure 1.

Dimensions in millimetres
Key
1 tensile test piece
2 tensile test piece
3 impact test piece
4 nominal diameter
5 notch
Figure 1 — Location of test pieces
---------------------- Page: 10 ----------------------
SIST-TS CEN/TS 15718:2011
CEN/TS 15718:2011 (E)
3.2.1.3 Test method

This shall be performed in accordance with EN ISO 6892-1. The test piece diameter shall be at least 10 mm in

the parallel length and the gauge length shall be 5 times the diameter.

NOTE If the wheel design prevents a sample of the stated size from being taken, a smaller sized sample may be

taken after agreement between the customer and supplier.
3.2.2 Hardness characteristics in the rim
3.2.2.1 Values to be achieved

Minimum values of Brinell hardness applicable to the whole wear zone of the rim shall be as given in Table 3.

These values shall be achieved up to a maximum depth of 35 mm under the tread, even if the wear depth is

higher than 35 mm. These measurements shall be taken from the points defined by B, C and D in Figure 2.

Hardness values in the rim-web transition (point A in Figure 2) shall be at least 10 points lower than the wear

limit values.
Table 3 — Minimum hardness values
Steel grade Minimum value for Brinell hardness
CER7 235
CER8 245
3.2.2.2 Location of readings

Four readings shall be carried out on a radial section of the rim as shown in Figure 2. Where the

microstructure of the wheel varies as a result of the casting process, the test locations shall occur in the worst-

case areas of the wheel.
Dimensions in millimetres
Key
1 limit of wear or last turning diameter (according to customer’s requirements)
2 inside surface of finished wheel
3 nominal diameter
Figure 2 — Readings taken on a radial section of the rim
---------------------- Page: 11 ----------------------
SIST-TS CEN/TS 15718:2011
CEN/TS 15718:2011 (E)
3.2.2.3 Test method

This shall be performed in accordance with EN ISO 6506-1. The ball diameter is 5 mm.

3.2.3 Impact test characteristics
3.2.3.1 Values to be achieved

Cast wheels shall have the average and minimum impact values as given in Table 4.

NOTE The values represent the average and minimum values for the three test specimens defined in 3.2.3.2.

At +20 °C, U-notch specimens shall be used. At -20 °C, V-notch specimens shall be used.

Table 4 — Average and minimum impact test characteristics
Steel grade KU (J) at +20 °C KV (J) at -20 °C
Average values Minimum values Average values Minimum values
CER7 ≥ 17 ≥ 12 ≥ 10 ≥ 7
CER8 ≥ 17 ≥ 12 ≥ 10 ≥ 5
3.2.3.2 Location of the test pieces
Test pieces shall be taken from the rim of the wheel, as indicated in Figure 1.
The bottom notch axis shall be parallel to the A-A axis of Figure 1.
3.2.3.3 Test method
This shall be performed in accordance with EN 10045-1.
3.2.4 Fatigue characteristics
3.2.4.1 Values to be achieved

Regardless of the steel grade, the web shall withstand the stress variation, Δσ, given in Table 5 during 10

cycles without any crack initiation, with a probability of 99,7 %.
Table 5 — Minimum fatigue characteristics
State of delivery of the web
N/mm
Fully machined 450
Partially machined or as cast and 315
shot peened

NOTE 1 The aim of these characteristics is to ensure that product characteristics are higher than those used for the

definition of permissible stresses for the fatigue design of the web.

NOTE 2 As there are many approximations in a fatigue calculation, it is not realistic to distinguish between the two

steel grades.
---------------------- Page: 12 ----------------------
SIST-TS CEN/TS 15718:2011
CEN/TS 15718:2011 (E)
3.2.4.2 Specimens for fatigue test

Specimens shall consist of wheels as delivered. Their surface appearances shall be those defined in 3.7.

3.2.4.3 Test method
The test method shall allow bending stresses to be created in a web section.

The tests to demonstrate the fatigue properties shall be performed in such a manner that statistical evaluation

to assess the results can be applied.

Tests shall be monitored by measuring the radial stresses which exist in the crack initiation area.

NOTE An example of the method is given in Annex B.
3.2.5 Fracture toughness characteristics of the rim
3.2.5.1 General

This characteristic shall only be verified on tread-braked wheels (service brake or parking brake).

3.2.5.2 Values to be achieved

For steel grade CER7, the average value obtained from six test pieces shall be greater than or equal to

2 2
80 N/mm m and any single value shall not be below a minimum of 70 N/mm m .
3.2.5.3 Location of test pieces

Six test pieces shall be taken from the rim as indicated in Figure 3. Where the microstructure of the wheel

varies as a result of the casting process, the test locations shall be in the worst-case areas of the wheel.

Dimensions in millimetres
Key
1 nominal diameter
Figure 3 — Test p
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.