National foreword

This British Standard is the UK implementation of EN 15551:2022. It supersedes BS EN 15551:2017, which is withdrawn.

The UK participation in its preparation was entrusted to Technical Committee RAE/3/-/7, Railway applications - Couplers.

A list of organizations represented on this committee can be obtained on request to its committee manager.

The UK committee draws users' attention to the distinction between normative and informative elements, as defined in Clause 3 of the CEN/CENELEC Internal Regulations, Part 3.

Normative: Requirements conveying criteria to be fulfilled if compliance with the document is to be claimed and from which no deviation is permitted.

Informative: Information intended to assist the understanding or use of the document. Informative annexes do not contain requirements, except as optional requirements, and are not mandatory. For example, a test method may contain requirements, but there is no need to comply with these requirements to claim compliance with the standard.

When speeds in km/h require unit conversion for use in the UK, users are advised to use equivalent values rounded to the nearest whole number. The use of absolute values for converted units should be avoided in these cases. Please refer to the table below for agreed conversion figures:

There are special national conditions relating to the United Kingdom, specified in Annex D (normative) of BS EN 16839:2022, which UK users should reference. Text from that Annex D (normative) is supplied below and references amended for application in this standard.

The UK loading gauge is much smaller than the gauge in Europe and the maximum axle load is higher at 25.4 tonnes. As a consequence of this, longer thinner wagons are built to maximize the pay load of wagons carrying lower density products.

In order to maximize the volumetric capacity of the wagon body within this overall length, we have continued to use 520 mm buffers with a head radius of 1250 mm to cater for the tighter curves found in many UK terminals, (for example Oleo OP176GX buffers). As BS EN 15551:2022 is referenced in the Wagon TSI, any new wagons would have to be built with 620 mm buffer and 2750 mm head radius.

This would have three effects:

1) The wagon bodies would have to be shorter to allow for the longer buffers within the same 18300 mm overall length with a corresponding loss of payload of typically 1 tonne on every journey.

2) The use of the 2750 mm head radius would push the drawbar loads over the 250 kN limit, when negotiating 70 m curves, which would necessitate lengthening the screw couplings every time the wagons went into tight terminals and tightening them again once they were back on the mainline. This would cause delays to arrivals and departures, add cost and present an additional safety hazard to the shunters.

3) If the 520 mm buffer is no longer used for new build wagons, the manufacturers will eventually cease to make them. The vast majority of UK bogie wagons are fitted with these buffers and any new casings required to replace worn ones would then need to be specially made at a vast increase in cost.

Therefore, wagons for use exclusively in UK should continue to use 520 mm projection buffers and the corresponding UK screw coupling, see BS EN 15566:2022.

Contractual and legal considerations

This publication has been prepared in good faith, however no representation, warranty, assurance or undertaking (express or implied) is or will be made, and no responsibility or liability is or will be accepted by BSI in relation to the adequacy, accuracy, completeness or reasonableness of this publication. All and any such responsibility and liability is expressly disclaimed to the full extent permitted by the law.

This publication is provided as is, and is to be used at the recipient’s own risk.

The recipient is advised to consider seeking professional guidance with respect to its use of this publication.

This publication is not intended to constitute a contract. Users are responsible for its correct application.

This publication has been prepared under a mandate given to the European Standards Organizations by the European Commission and the European Free Trade Association. It is intended to support requirements of the EU legislation detailed in the European Foreword. A European Annex, usually Annex ZA or ZZ, describes how this publication relates to that EU legislation.

For the Great Britain market (England, Scotland and Wales), if UK Government has designated this publication for conformity with UKCA marking (or similar) legislation, it may contain an additional National Annex. Where such a National Annex exists, it shows the correlation between this publication and the relevant UK legislation. If there is no National Annex of this kind, the relevant Annex ZA or ZZ in the body of the European text will indicate the relationship to UK regulation applicable in Great Britain. References to EU legislation may need to be read in accordance with the UK designation and the applicable UK law. Further information on designated standards can be found at

www.bsigroup.com/standardsandregulation.

For the Northern Ireland market, UK law will continue to implement relevant EU law subject to periodic confirmation. Therefore Annex ZA/ZZ in the European text, and references to EU legislation, are still valid for this market.

UK Government is responsible for legislation. For information on legislation and policies relating to that legislation, consult the relevant pages of www.gov.uk.

Compliance with a British Standard cannot confer immunity from legal obligations.

This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 September 2022.

This European Standard was approved by CEN on 10 July 2022.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC 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 translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.

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 foreword

This document ( EN 15551:2022) has been prepared by Technical Committee CEN/TC 256 “Railway applications”, the secretariat of which is held by DIN.

This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by February 2023, and conflicting national standards shall be withdrawn at the latest by February 2023.

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 supersedes EN 15551:2017.

Compared with EN 15551:2017 the following main changes have been done:

Redrawn of the following Figures:
1. Figure 2 — Fixing dimensions of 105 mm stroke and 150 mm stroke buffers for interchangeability;
2. Figure F.1 — Definition of heights;
3. Figure F.2 — Representation of the stored energy;
4. Figure F.3 — Endurance test under service load;
5. Figure G.1 — Determination of buffer strokes for endurance test;
Adaption of this document in relation to the intersection contents on EN 16839:
1. Adaption of the Scope;
2. Deleting of 4.6 “Interaction coupling/buffer”;
3. Adaption on 5.1 “General”;
4. Figure 2 — Mounting of buffers with non-metallic insert or head (top view for freight wagons) is deleted
5. Deleting of 6.2.2 “Boundary dimensions”;
6. Adaption on 6.2.3.1 “General” and 6.2.3.2 “Buffers with stroke of 105 mm...”;
7. The former Table 6 about standard width have been exported to EN 16839.
8. Deleting of Annex I “Calculation of the width of buffer heads”.
editorial modifications.

This document has been prepared under a standardization request addressed to CEN by the European Commission, and it aims to support essential or other requirements of EU Directive(s) or Regulation(s).

For relationship with EU Directive(s) or Regulation(s), see informative Annex ZA, which is an integral part of this 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 implement this European Standard: 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 the United Kingdom.

Introduction

This document is based on UIC 526-1:2008, UIC 526-3:2008, UIC 528:2007, UIC 573:2007, UIC 827-1:1990 and UIC 827-2:1981.

1 ⁠⁠⁠⁠Scope

This document defines the requirements for buffers with 105 mm, 110 mm and 150 mm stroke for vehicles or units which use buffers and screw coupling. It covers the functionality, interfaces and testing procedures, including pass fail criteria, for buffers.

NOTE 1 Typically, buffers with a stroke of 105 mm are used on freight wagons and locomotives, buffers with a stroke of 110 mm are used on coaches and locomotives and buffers with a stroke of 150 mm are used on freight wagons.

It defines the different categories of buffers, the space envelope, static and dynamic characteristics and energy absorption.

It defines the static and dynamic characteristics of the elastic systems.

It also defines the requirements for buffers with integrated crash elements (crashworthy buffers) for tank wagons for dangerous goods.

The requirements of this document also apply to buffers of locomotives and passenger coaches which are bound to meet the crashworthiness requirements of EN 15227 for normal service only. The properties for the energy absorbing function are defined in EN 15227 and the requirements specified in Clause 7 for tank wagons for dangerous goods are not applicable to the buffers of these locomotives and passenger coaches.

Diagonal buffers are excluded from this document.

For the crashworthy buffers of locomotives, driving trailer or passenger coaches according to EN 15227, and tank wagons for dangerous goods or buffers which form part of a combined system consisting of a special buffer and a deformation element, interchangeability with freight wagon buffers is not required, and therefore the requirements of 5.3 (Buffer dimensions) do not apply, those of 5.4 (Mechanical characteristics of buffers) and 5.6 (Marking) apply with restrictions.

NOTE 2 For tank wagons subjected to dangerous goods regulation see [41].

Provisions going beyond the scope of this document may be agreed in the Technical Specification. The Technical Specification is not a mandatory document.

2 ⁠⁠⁠⁠Normative references

3 ⁠⁠⁠⁠Terms and definitions

4 ⁠⁠⁠⁠Classification and designation

4.1 ⁠⁠⁠⁠General

4.2 ⁠⁠⁠⁠Buffers with buffer stroke 105 mm (Categories A, B and C)

4.3 ⁠⁠⁠⁠Buffers with buffer stroke 110 mm

4.4 ⁠⁠⁠⁠Long stroke buffer 150 mm

4.5 ⁠⁠⁠⁠Crashworthy Buffers

5 ⁠⁠⁠⁠Requirements

5.1 ⁠⁠⁠⁠General

5.2 ⁠⁠⁠⁠Fixing on vehicle and interchangeability

5.3 ⁠⁠⁠⁠Buffer dimensions

5.4 ⁠⁠⁠⁠Mechanical characteristics of buffers

5.5 ⁠⁠⁠⁠Elastic systems

5.6 ⁠⁠⁠⁠Marking

6 ⁠⁠⁠⁠Housing

6.1 ⁠⁠⁠⁠Plunger and base

6.2 ⁠⁠⁠⁠Buffer head

6.3 ⁠⁠⁠⁠Type and series tests

7 ⁠⁠⁠⁠Crashworthy buffers

7.1 ⁠⁠⁠⁠On wagons

7.2 ⁠⁠⁠⁠On other vehicles

Bibliography

BS EN 15551:2022

Railway applications. Railway rolling stock. Buffers

Current

Published:

30 Sep 2022