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BRITISH STANDARDShort link chain for lifting purposes SafetyPart 4: Chain slings Grade 8The European Standard EN 818-4 : 1996 has the status of aBritish StandardICS | BS EN818-4 : 1997|NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWCommittees responsible for thisBritish StandardThe preparation of this British Standard was entrusted by Technical CommitteeMHE/1 upon which the following bodies were represented:British Cable Makers Confederation British Chain Manufacturers Association British Forging Industry AssociationBritish Iron and Steel Producers AssociationBritish Ports AssociationBritish Railways BoardCastings Technology InternationalCorporation of Trinity HouseDepartment of Trade and Industry (National Physical Laboratory) Drop Forging Research AssociationEngineering Equipment and Material Users Association Federation of Users of Construction Equipment and Cranes Federation of Wire Rope Manufacturers of Great Britain Health and Safety ExecutiveInstitution of Incorporated Executive EngineersLifting Equipment Engineers AssociationLloyds Register of ShippingMinistry of DefenceNational Association of Lift MakersThis British Standard, having been prepared under the direction of the Engineering Sector Board, was published under the authority of the Standards Board and comes into effect on15 April 1997BSI 1997The following BSI references relate to the work on this standard:Committee reference MHE/1Draft for comment 92/80473 DCISBN 0 580 26466 1Amd. No.DateText affectedAmendments issued since publicationBS 818-4 : 1997ContentsPage Committees responsible Inside front cover National foreword ii Foreword 2Text of EN 818-43BSI 1997iNational forewordThis British Standard has been prepared by Technical Committee MHE/1 and is the English language version of EN 818-4 : 1996, published by the European Committee for Standardization (CEN).EN 818-4 : 1996 was produced as a result of international discussions in which theUnited Kingdom took an active part.Compliance with a British Standard does not of itself confer immunity from legal obligations.Summary of pagesThis document comprises a front cover, an inside front cover, pages i to ii, the EN title page, pages 2 to 16, an inside back cover and a back cover.iiBSI 1997EUROPEAN STANDARDEN 818-4NORME EUROPE ENNEEUROPA ISCHE NORMJune 1996ICS Descriptors: Lifting chains, welded chains, chain links, lifting slings, safety, accident prevention, hazards, dimensions, dimensional tolerances, proof force, tests, verification, markingEnglish versionShort link chain for lifting purposes Safety Part 4: Chain slings Grade 8Chanes de levage a maillons courts Se curite Partie 4: Elingues en chanes Classe 8Kurzliedrige Rundstahlketten fu r Hebezwecke Sicherheit Teil 4: Anschlagketten Gu teklasse 8This European Standard was approved by CEN on 1996-03-07. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.CENEuropean Committee for Standardization Comite Europe en de Normalisation Europa isches Komitee fu r NormungCentral Secretariat: rue de Stassart 36, B-1050 Brussels1996 Copyright reserved to CEN members.Ref. No. EN 818-4 : 1996 EForewordThis European Standard has been prepared byTechnical Committee CEN/TC 168, Chains, ropes,ContentsPagewebbing, slings and accessories Safety, of which theSecretariat is held by BSI.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 byDecember 1996, and conflicting national standards shall be withdrawn at the latest by December 1996.This European Standard 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(s).The other Parts of EN 818 are:Part 1: General conditions of acceptance;Part 2: Medium tolerance chain for chain slings Grade 8;Part 3: Medium tolerance chain for chain slings Grade 4;Part 5: Chain slings Grade 4;Part 6: Chain slings Instructions for use and maintenance.A further Part or Parts will cover fine tolerance chains for chain hoists and other lifting appliances.This is the first edition of this Part of EN 818.In accordance with the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland,Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.Foreword 2Introduction 31 Scope 32 Normative references 33 Definitions 34 Hazards 45 Safety requirements 46 Verification of safety requirements 57 Marking 78 Manufacturers certificate 79 Instructions for use 7AnnexesAnnex A (normative) Alternative method of rating and marking a chain sling for aspecific lifting application 13Annex B (informative) Bases for calculationof working load limits 13Annex C (informative) Designation systemfor chain slings grade 814Annex D (informative) Identification tagsfor chain slings 15IntroductionThis European Standard has been prepared to be a harmonized standard to provide one means of conforming with the essential safety requirements of the Machinery Directive.The Directive stipulates that where chain with welded links is used for lifting accessories it is to be of short line type and for the purposes of this standard this is chain having a ratio of nominal pitch to nominal size of 3:1.The extent to which hazards are covered is indicatedEN 292-1Safety of machinery Basic concepts General principles for designPart 1: Basic terminology, methodologyEN 292-2 : 1991 Safety of machinery Basic concepts General principles for designPart 2: Technical principles and specificationsEN 292-2 : 1991/ Safety of machinery Basicin the scope of this Part of EN 818. In addition, lifting equipment shall comply as appropriate to EN 292 for hazards which are not covered by this standard.Annex C gives a designation system for recording the identifying features of grade 8 chain slings. Since thisA1 : 1995concepts General principles fordesignPart 2: Technical principles and specifications(Amendment 1 : 1995)system is not widely used it has been included in this first edition of this standard as an informative annex; however, should its use become more generally accepted then the status of the information would need to be reviewed.1 ScopeThis European Standard specifies the requirements related to safety, methods of rating and testing of single-, two-, three-, four-leg and endless chain slings, assembled by:a) mechanical joining devices;b) weldingusing short link grade 8 medium tolerance lifting chain conforming to EN 818-2 together with the appropriate range of components of the same grade.NOTE. Instructions for use and maintenance of chain slings are covered by prEN 818-6.The hazards covered by this European Standard are identified in clause 4.Bases for the calculation of working load limits are given in annex B.EN 818-1Short link chain for liftingpurposes SafetyPart 1: General conditions of acceptanceEN 818-2Short link chain for lifting purposes SafetyPart 2: Medium tolerance chain for chain slings Grade 8prEN 818-6Short link chain for lifting purposes SafetyPart 6: Chain slings Instructions for use and maintenanceprEN 1050Safety of machinery Principles of risk assessmentprEN 1677-1Components for slings Safety Part 1: Forged steel components Grade 8prEN 1677-2Components for slings SafetyPart 2: Forged steel lifting hooks with latch Grade 8prEN 1677-4Components for slings SafetyPart 4: Links Grade 8Annex C gives an example of a designation system for chain slings.2 Normative referencesEN ISO 9001 :1994Quality systems Model for quality assurance in design/development, production, installation and servicingThis European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to, or revisions of, any of these publications apply to this European Standard onlywhen incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies.3 DefinitionsFor the purposes of this Part of EN 818 the following definitions apply.3.1 chain slingAn assembly consisting of chain or chains joined to upper and lower terminals suitable according to the requirements of this European Standard for attaching loads to the hook of a crane or other lifting machine (see figures 1 to 4).3.2 nominal size of slingThe nominal size of short link chain, in millimetres, used in the manufacture of the sling.3.3 nominal grade of slingFor the purpose of designation in accordance with annex C, the same as the grade of the short link chain used in the manufacture of the sling, . 8.3.4 master linkA link forming the upper terminal of a chain by means of which the sling is attached to the hook of a crane of other lifting machine (see figures 1 to 4).3.5 length of a legFor a finished sling, the length from the lower bearing point of the lower terminal to the upper bearing point of the upper terminal (see figures 1 to 4 as examples).3.6 intermediate master linkA link used to connect one or two legs of a sling to a master link.3.7 lower terminalA link, hook or other device fitted at the end of a leg of a sling, remote from the master link or upper terminal.3.8 mechanical joining deviceA means of connection which does not depend on welding. It may be integral with a component or a separate component (see figure 5).3.9 joining linkA welded link fitted to the end of a chain to connect it either directly or through an intermediate link to an upper or lower terminal or intermediate master link, or in the case of an endless sling to the other end of the chain (see figures 1 to 4).0 intermediate linkA welded link used to form a connection between the terminal and the joining link fitted to the chain (see figures 1 to 4).3.11 manufacturing proof force (MPF) of a chain slingA force applied during manufacture as a test to the whole sling or a force applied as a test to a section of a sling.2 working load limit (WLL) of a chain slingThe maximum mass which a sling is authorized to sustain in general lifting service.3 competent personA designated person, suitably trained (see 8 of EN ISO 9001 : 1994) qualified by knowledge and practical experience, and with the necessary instructions to enable the required tests and examination to be carried out.4 HazardsThe release of a load due to failure of lifting accessories such as slings or their component parts puts at risk either directly or indirectly the life or health of those persons within the danger zone of lifting equipment.In order to provide the necessary strength and durability of lifting accessories, this Part of EN 818 lays down requirements for the design, selection ofmaterials of construction and testing to ensure that specified levels of performance are met.Fatigue failure has not been identified as a hazard when chain slings having the specified levels of performance given in this Part of EN 818 are used in general lifting service.Since failure can be caused by the incorrect choice of grade and specification of lifting accessory this Part of EN 818 also gives the requirements for marking andthe manufacturers certificate.Errors in fitting together of assemblies can also lead to premature failure and this Part of EN 818 contains dimensional requirements to allow correct fit.Those aspects of safe use associated with good practice are given in prEN 818-6.Table 1 contains all the hazards which require action to reduce risk, identified by risk assessment as being specific and significant for chain slings grade 8.5 Safety requirements5.1 Components of a chain sling5.1.1 ChainThe chain shall comply with prEN 818-2.5.1.2 Forged steel componentsForged steel components, including mechanical joining devices, for use with grade 8 chain in the manufacture of chain slings shall conform to prEN 1677-1.Table 1. Hazards and associated requirementsHazards identified in annex A of prEN 1050Relevant clause of annex A ofEN 292-2 : 1991/A1 : 1995Relevant clause/sub-clause of thisPart of EN 818Mechanical hazard due to inadequacy of strength567815Errors of fitting hazard5.1.3 LinksMaster links and intermediate master links shall comply with prEN 1677-4.Lower terminal links shall comply with prEN 1677-4 except for those clauses relating to link dimensions. Joining links and intermediate links shall conform with prEN 1677-4 except for those clauses related to linkdimensions.Lower terminal links, joining links and intermediate links shall satisfy the appropriate requirements of .5.1.4 HooksForged steel lifting hooks with latch shall comply with prEN 1677-2.Hooks not covered by these standards shall comply with .NOTE. The details of forged steel self-locking hooks are contained in prEN 1677-3, which is in the course of preparation.5.2 Design and construction5.2.1 Slings assembled with mechanical joining devices5.2.1.1 The assembly of the sling shall be undertaken in accordance with the chain manufacturers instructions.5.2.1.2 Slings shall be so designed and manufactured that when assembled in accordance with the manufacturers instructions, the unintentional disconnection of any component part cannot occur.5.2.1.3 Pear-shaped links shall only be used if they have an integral joining device.5.2.1.4 Assembled mechanical joining devices shall have a working load limit not less than that of the chain(s) to which they are connected in a chain sling.5.2.1.5 The component parts of the chain sling shall comply with the requirements of 5.1 except in respect of joining and intermediate links.5.2.2 Slings assembled by welding5.2.2.1 Pear-shaped links shall not be used as terminals.5.2.2.2 Joining links and intermediate links shall have a working load limit not less than that of the chain(s) to which they are connected in a chain sling.5.2.2.3 The dimensions of joining links and intermediate links shall be such as to ensure adequate articulation with parts of the chain sling which they connect.5.2.2.4 The component parts of the sling shall comply with the requirements of .5.2.3 Endless slingsThe manufacture of an endless sling shall be either by the use of:a) a mechanical joining device; orb) a welded joining link of the same size or one size larger than the nominal size of chain.5.2.4 Tolerance on length5.2.4.1 When constructing a sling the actual length of each leg shall be the nominal length with a toleranceof +2 chain link pitches.05.2.4.2 When constructing a multi-leg sling, the difference in length between the longest and shortest legs which are nominally the same length shall, when measured under equivalent tension, comply with the value given in table 2.5.3 Working load rating5.3.1 Single-leg slingsSingle-leg slings shall be rated at a working load limit in accordance with table 3.5.3.2 Multi-leg slingsMulti-leg slings shall be rated for symmetrically distributed loads only, and in accordance with table 3.Each sling shall have a single working load limit for the range of angles from 0 up to and including 45 to the vertical or additionally a working load limit for the range of angles from 45 up to and including 60 to the vertical.NOTE 1. An alternative method for rating and marking of slings when not for use in general service is given in annex A.NOTE 2. For rating of slings with asymmetrically distributed loads see prEN 818-6.5.3.3 Endless slingsEndless slings shall be rated for choke-hitch only and be in accordance with table 3.6 Verification of safety requirements6.1 Manufacturing proof force6.1.1 GeneralUnless b applies, assembled slings with accessories shall be subjected to a manufacturing proof force test.Each individual section of a sling . MPF1, MPF2, MPF3 and MPF4 in figure 6) shall be subjected to a force at least equal to 2,5 times its working load limit in accordance with .Table 2. Tolerance on lengthMultiple leg slingsType of slingDifference in length between the longest and shortest legsNominal lengths up to and including 2 mNominal lengths over 2 mJoined by mechanical devices10 mm max.5 mm/mAssembled by welding6 mm max.3 mm/mTable 3. Working load limitsNominal size of slingmmWorking load limits, t, forSingle-leg slingsTwo leg slingsThree- and four-leg slingsEndless slings in choke hitch0 b # 4545 b # 600 b # 4545 b # 60Factor 1,4Factor 1,0Factor 2,1Factor 1,5Factor 1,6456781013161819202223252628323640450,50,81,121,523,155,381011,212,515162021,22531,54050630,711,121,62,122,84,257,511,214161721,223,6283033,5455671900,50,81,121,5
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