SIST EN 15049:2008

Railway applications - Suspension components - Torsion bar, steel

This European Standard applies to torsion bars made of steel for anti-roll bar systems used on railway vehicles.
This European Standard includes straight and bended torsion bars, but does not detail the other components of the anti-roll bar systems such as levers, bearings, bushes etc.
This European Standard constitutes guidelines on the following topics:
-   design;
-   specification of technical requirements;
-   production requirements;
-   tests;
-   supply conditions.

Bahnanwendungen - Federungselemente - Drehstabfedern aus Stahl

Diese Europäische Norm gilt für Drehstabfedern aus Stahl für Wankstützen-Systeme in Schienenfahrzeugen.
Diese Europäische Norm beinhaltet gerade und gebogene Drehstabfedern, nicht aber die anderen Kompo¬nenten des Wankstützsystems wie Hebel, Lagerungen, Buchsen, usw.
Diese Europäische Norm ist eine Anleitung zu folgenden Themen:
   Konstruktion;
   Spezifikation technischer Anforderungen;
   Anforderungen an die Fertigung;
   Prüfungen;
   Lieferbedingungen.

Applications ferroviaires - Éléments de suspension - Barre de torsion, en acier

La présente Norme Européenne s'applique aux barres de torsion en acier pour les systèmes de barres anti-roulis utilisés sur les véhicules ferroviaires.
La présente Norme Européenne inclut les barres de torsion droites et coudées mais ne détaille pas les autres composants des systèmes de barres anti-roulis tels que les leviers, paliers, coussinets, etc.
La présente Norme Européenne constitue un ensemble de lignes directrices sur les sujets suivants :
   conception ;
   spécification d'exigences techniques ;
   exigences de production ;
   essais ;
   conditions de fourniture.

Železniške aplikacije - Vzmetenje - Torzijska vzmet, jeklena

General Information

• Status: Published
• Publication Date: 02-Mar-2008
• ICS: 21.160 - Springs
• ICS: 45.040 - Materials and components for railway engineering
• Technical Committee: IŽNP - Reilway applications
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 22-Feb-2008
• Due Date: 28-Apr-2008
• Completion Date: 03-Mar-2008
• Directive: 93/38/EEC - Procurement procedures of entities operating in the water, energy, transport and telecommunications sectors
• Mandate: M/024 - Mandate to CEN/CENELEC/ETSI for programming and standardization in the field of railway equipment
• Ref Project: EN 15049:2007 - Railway applications - Suspension components - Torsion bar, steel

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Železniške aplikacije - Vzmetenje - Torzijska vzmet, jeklenaBahnanwendungen - Federungselemente - Drehstabfedern aus StahlApplications ferroviaires - Éléments de suspension - Barre de torsion, en acierRailway applications - Suspension components - Torsion bar, steel45.040Materiali in deli za železniško tehnikoMaterials and components for railway engineering21.160VzmetiSpringsICS:Ta slovenski standard je istoveten z:EN 15049:2007SIST EN 15049:2008en,fr,de01-april-2008SIST EN 15049:2008SLOVENSKI
STANDARD
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 15049August 2007ICS 45.060.01 English VersionRailway applications - Suspension components - Torsion bar,steelApplications ferroviaires - Éléments de suspension - Barrede torsion, en acierBahnanwendungen - Federungselemente - Drehstabfedernaus StahlThis European Standard was approved by CEN on 13 July 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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 STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2007 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15049:2007: ESIST EN 15049:2008

Material for hot formed and quenched and tempered torsion bars.28 A.1 General.28 A.2 Material for torsion bars, steel.28 Annex B (normative)
Inspection of torsion bars made of round bars by the magnetic crack detection method.30 B.1 Object.30 B.2 Tests.30 B.3 Safety measures.30 Annex C (normative)
Checking shot peening efficiency by ALMEN method.31 C.1 Field of application.31 C.2 Checking the procedure.31 C.3 Equipment and installations.31 C.3.1 ALMEN A2 test piece.31 C.3.2 Test piece holder.32 C.3.3 ALMEN measuring device.33 Annex D (normative)
Examination for inclusions.34 D.1 Object.34 D.2 Test methods.34 D.2.1 Test method according to DIN 50602.34 D.2.2 Test method according to NF A 04-106.35 D.2.3 Test method according to SS 111116.35 Annex E (normative)
Taking of test pieces - Areas of the location of test pieces.36 Bibliography.38
Tables Table 1 — Symbols and definitions.8 Table 2 — Elements to be defined in the technical specification and agreed by the parties.10 Table 3 — Checks and tests to be carried out.24 Table 4 — Test pieces for statistical tests, number of tests.25 Table A.1 — Guidance values for the maximum mechanical properties of quenched and tempered test pieces.29 Table D.1 — Degree of cleanliness under the microscope according to DIN 50602 (procedure K), valid for non metallic oxide inclusions.34 Table D.2 — Acceptable number of fields (small series and wide series) of each type.35 Table D.3 — Degree of cleanliness by microscopic examination according to SS 111116 (maximum values).35
(ISO 9934-1:2001) EN ISO 14284, Steel and iron — Sampling and preparation of samples for the determination of chemical composition (ISO 14284:1996) EN ISO 18265, Metallic materials — Conversion of hardness values (ISO 18265:2003) DIN 50602, Metallographic examination — microscopic examination of special steels using standard diagrams to assess the content of non-metallic inclusions NF A04-106, Iron and steel. Methods of determination of content of non metallic inclusions in wrought steel. Part II: micrographic method using standards diagrams SS 111116, Steel — Method for estimation of the content of non-metallic inclusions — Microscopic methods — Jernkontoret's inclusion chart II for the assessment of non-metallic inclusions 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN ISO 2162-3:1996 and the following apply. 3.1 anti-roll bar system suspension system having an influence on the rolling behaviour of the vehicle. Generally, it includes the torsion bar and any other components 3.2 anti-roll bar spring bar which is mainly stressed by a torsional moment. It can either be produced as bended bar or a straight torsion bar with levers 3.3 straight torsion bar straight spring bar which is mainly stressed by a torsional moment NOTE The term "torsion bar made of steel" refers to the finished end product. For the purpose of simplification, the term "torsion bar" is used in the wording of this European Standard for anti-roll bars with torsion bars of round cross section and made of steel. 3.4 bended torsion bar mainly U-shaped and manufactured out of round spring material SIST EN 15049:2008

Table 1 can be used. Table 1 — Symbols and definitions Symbols Units Definitions A % Elongation at rupture d m Outer diameter of the middle part of the torsion bar da m Outer diameter of the torsion bar in the area of bearing df m Root diameter of the head profile dp m Diameter of shrink fit e m Area to take test pieces F N Applied load at the lever l m Distance between load application and middle of torsion bar Lf m Distance between the two load application points La m Length between the centre of the two bearings Ls m Length between the centre of the two levers lx m Crank depth in the middle part of the torsion bar lz m Distance between load application and centre of the bearing Mt Nm Torsional moment Mtmax Nm Max. torsional moment ûMt Nm Difference of torsional moments r M Bending radius of bended torsion bar SIST EN 15049:2008

Figure 1 — Example for a straight torsion bar with mounted levers
Figure 2 — Example for a bended torsion bar SIST EN 15049:2008

Figure 3 — Cylindrical or conical tooth system NOTE Special care should be taken when using cylindrical toothings for torsion bar heads subjected to alternating stress because of clearance.
Key dp
recommended shrink fit to be entered Figure 4 — Frictional shrink fit SIST EN 15049:2008

0,1 × fatigue strength);  a variable loading with greater stress range but only a number of cycles of up to 104. A dynamic loading is:  a loading variable with time with a number of loading cycles over 104 and stress range greater than
0,1 × fatigue strength at: a) a range of constant stress; b) a range of variable stress. 6.2.3 Investigation of the strain The strain in the cross section of torsion bars is a combination of torsional and bending stress. The comparison-tension can be adequately determined analytically with existing calculation programs. A verification by means of a Finite Element Method (FEM) analysis can take place according to application-case. SIST EN 15049:2008

NOTE For life time estimation, life cycle diagrams for alternate loaded parts could be taken from the existing literature or from experience of the supplier. 6.3 Physical requirements 6.3.1 Material grade The characteristics of the material shall be appropriate to the requirements specified in the technical specification. The alloy to be used for the manufacture of the torsion bar shall be defined. It is recommended to use the alloys defined in EN 10089 (see also Annex A). It is permitted to use alloys different to those defined in EN 10089. In this case, the chemical and mechanical characteristics shall be completely defined. The alloy of the torsion bar material shall be in accordance to Annex A for recommended material qualities. 6.3.2 Internal integrity The material of the torsion bar shall not exhibit internal faults which would prove detrimental in use. Where it is necessary to establish that the internal integrity is acceptable, then tests as defined in 8.16 are to be carried out. 6.3.3 Inclusion cleanliness The contents of the non-metallic inclusions verified by one of the test methods as defined in Annex D shall be within the limits given in Annex D, unless otherwise defined in the technical specification. 6.3.4 Forged torsion bar ends If not agreed otherwise, the torsion bar ends are forged. When forging the torsion bar heads, attention shall be paid to the correct course of the fibres. The fibre course is checked in according to 8.9. SIST EN 15049:2008

- 500 MPa at / = 0,1 mm, 1D ≤
- 100 MPa at / = 0,3 mm inside the material. The use of sharp-edged shot is not allowed. SIST EN 15049:2008

Key + tension - compression Figure 5 — Example of the distribution of stresses produced by shot peening as a function of depth 6.3.8 Grain size The index value of the austenitic grain size defined according to EN ISO 643 shall be 7 or higher. 6.4 Surface protection 6.4.1 Generalities There are two kinds of protection: A temporary protection: Designed surfaces shall be protected against corrosion as minimum until mounting of the torsion bar on the vehicle. A permanent protection: Designed surfaces shall be protected against corrosion during a defined period of functioning in service. 6.4.2 Temporary protection The system selected and its duration of efficiency shall be defined by the supplier in the definition documents of the torsion bar and submitted to agreement by the customer. 6.4.3 Permanent protection The customer shall define in the technical specification its requirements such as:  the decoration characteristics (colour, reflecting brightness etc.);  the mechanical characteristics (resistance to impact, gravelling, abrasion, deformation by folding etc.);  the ageing characteristics (resistance to salt spray etc.). The system of protection against corrosion shall be defined on the component drawing of the torsion bar. SIST EN 15049:2008

∆Mt = Mt2 – Mt1 ∆ϑϑϑϑ = ϑϑϑϑ2 - ϑϑϑϑ1 ϑ∆∆=tMRt Figure 6 — Torsion bar diagram NOTE -Mt1 to -Mt3 and -ϑϑϑϑ1 to -ϑϑϑϑ3 are values for the counter loading direction. The characteristic moment of torsion / angular displacement is determined by using the following equation: Rt = (Mt2 - Mt1) / (ϑϑϑϑ2 - ϑϑϑϑ1) with: Mt1 < Mt2 and ϑϑϑϑ1 < ϑϑϑϑ2 NOTE Values of Mt1 and ϑϑϑϑ1 can be negatives when the characteristic is defined on an alternative movement (crossing by 0). SIST EN 15049:2008

3.1-certificate of EN 10204. The verification of the characteristics of the material shall be carried out according to the requirements of
EN 10089. Unless otherwise specified in the technical specification, the chemical composition shall be determined by means of a chemical analysis of a cross section of material, taken from the raw bar. The conditions of sampling shall be in accordance with EN ISO 14284. SIST EN 15049:2008
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