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BRITISH STANDARDShort link chain for lifting purposes Safety Part 3: Medium tolerance chain for chain slings Grade 4The European Standard EN 818-3:1999 has the status of aBritish StandardICS | BS EN818-3:1999|NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBS EN 818-3:1999National forewordThis British Standard is the English language version of EN 818-3:1999. It supersedesBS 4942-3:1981 which is withdrawn.The UK participation in its preparation was entrusted to Technical CommitteeMHE/1, Chains and fittings, which has the responsibility to: aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK.A list of organizations represented on this committee can be obtained on request to its secretary.Cross-referencesThe British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled International Standards Correspondence Index, or by using theFind facility of the BSI Standards Electronic Catalogue.A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application.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, the EN title page, pages 2 to 13 and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amd. No.DateCommentsThis British Standard, having been prepared under the direction of the EngineeringSector Committee, was published under the authority of the Standards Committee and comes into effect on 15 September 1999BSI 09-1999ISBN 0 580 32562 8Amendments issued since publicationEUROPEAN STANDARDEN 818-3NORME EUROPENNEEUROPISCHE NORMMay 1999ICS English versionShort link chain for lifting purposes Safety Part 3: Medium tolerance chain for chain slings Grade 4Chanes de levage maillons courts Scurit Partie 3: Chanes de tolrance moyenne pour lingues en chanes Classe 4Kurzgliedrige Rundstahlketten fr Hebezwecke Sicherheit Teil 3: Mitteltolerierte Rundstahlketten fr Anschlagketten Gteklasse 4This European Standard was approved by CEN on 16 April 1999.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, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.CENEuropean Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr NormungCentral Secretariat: rue de Stassart 36, B-1050 Brussels 1999 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN nationalMembers.Ref. No. EN 818-3:1999 EContentsPageForeword30 Introduction41 Scope42 Normative references43 Terms and definitions54 Hazards55 Safety requirements56 Verification of safety requirements87 Marking108 Manufacturers certificate109 Instructions for use10Annex A (informative) Calculation of dimensions, working load limits and mechanical properties10Annex B (informative) Mass of chain12Annex C (informative) Designation system for chain (medium tolerance) Grade 413Annex ZA (informative) Relationship of this European Standard with EU Directives13ForewordThis European Standard has been prepared by Technical Committee CEN/TC 168, Chains, ropes, webbing, slings and accessories Safety, the Secretariat of which 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 by November 1999, and conflicting national standards shall be withdrawn at the latest by November 1999.This European Standard has been prepared under a mandate given to CEN by the European Commission and theEuropean Free Trade Association, and supports essential requirements of EU Directive(s).For relationship with EU Directive(s), see informative annex ZA, which is an integral part of this standard. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the followingcountries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.The other parts of EN 818 are:Part 1: General conditions of acceptancePart 2: Medium tolerance chain for chain slings Grade 8Part 4: Chain slings Grade 8Part 5: Chain slings Grade 4Part 6: Chain slings Specification for information for use and maintenance to be provided by the manufacturerPart 7: Fine tolerance chains for hoists, Grade T (types T, DAT, DT)This is the first edition of this part of EN 818.0 IntroductionThis European Standard has been prepared to be a harmonized standard to provide one means of complying with the essential safety requirements of the Machinery Directive and associated EFTA regulations.The Directive stipulates that, where chain with welded links is used for lifting accessories, it is to be of short link 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 indicated in the Scope. In addition, lifting equipment shall conform as appropriate to EN 292 for hazards which are not covered by this standard.1 ScopeThis part of EN 818 specifies the requirements related to safety for short link lifting chains, grade 4, of medium tolerance for use in chain slings and for general lifting purposes. The standard is applicable to electricallywelded round steel short link chains, conforming to EN 818-1, which are intended for lifting objects, materials or goods.The range of nominal sizes of chain covered by this part of EN 818 is from 7 mm to 45 mm. The hazards covered by this part of EN 818 are identified in clause 4.Annex A contains the bases for calculation of tabulated values for dimensions, working load limits and mechanical properties.Annex B gives information on the mass/metre of chain.Annex C gives an example of a designation system for chains of grade 4. Annex ZA gives the relationship with EU Directives.2 Normative referencesThis European Standard incorporates, by dated or undated reference, provisions from other publications. These normative references are cited at 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 only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies.EN 292-1, Safety of machinery Basic concepts, general principles for design Part 1: Basic terminology, methodology.EN 292-2:1991/A1:1995, Safety of machinery Basic concepts, general principles for design Part 2: Technical principles and specifications.EN 818-1:1996, Short link chain for lifting purposes Safety Part 1: General conditions of acceptance.prEN 818-6, Short link chain for lifting purposes Safety Part 6: Chain slings Specification for information for use and maintenance to be provided by the manufacturer.EN 1050:1996, Safety of machinery Principles for risk assessment.EN 10025:1990/A1:1993, Hot rolled products of non-alloy structural steels Technical delivery conditions(includes amendment A1:1993).ISO 643, Steels Micrographic determination of the ferritic or austenitic grain size.3 Terms and definitionsFor the purposes of this part of EN 818, the terms, definitions and symbols given in EN 818-1:1996 apply.4 HazardsThe release of a load due to failure of lifting accessories such as chain slings or their component parts puts at risk either directly or indirectly the safety 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, manufacture and testing to ensure that specified levels of performance are met.Fatigue failure has not been identified as being a hazard when chain, having the specified levels of performance given in this part of EN 818, is used in general lifting service.Since failure can be caused by the incorrect choice of grade and specification of lifting accessories this part ofEN 818 also gives the requirements for marking and the manufacturers certificate. Those aspects of safe use associated with good practice are given in prEN 818-6.Table 1 contains those hazards which require action to reduce risk identified by risk assessment as being specific and significant for short link chain (medium tolerance) grade 4.Table 1 Hazards and associated requirementsHazards identified in EN 1050:1996, annex ARelevant clause of EN 292-2:1991/A1:1995, annex ARelevant clause/subclause of this part of EN 8181e)Mechanical hazard due toinadequacy of strength55567895 Safety requirements5.1 GeneralThe chain shall also conform to the appropriate requirements of EN 818-1:1996.5.2 Dimensions5.2.1 Nominal size of chain, dnThe nominal size of the chain shall be one of the sizes listed in Table 2, column 1.5.2.2 Tolerance on material diameter (except at the weld)The tolerance on the material diameter for each nominal size of chain shall be in accordance with Table 2, column 2.5.2.3 Weld diameterThe maximum diameter at the weld for each nominal size of chain shall be in accordance with Table 2, column 3.The thickness of the steel at the weld shall nowhere be less than the actual diameter of the steel adjacent to the weld.5.2.4 Length dimensionally affected by weldingThe length dimensionally affected by welding e (see EN 818-1:1996, Figure 1) shall not extend by more than0,6dn to either side of the centre of the link.5.2.5 Pitch and widthsThe dimensions of the pitch and widths of the individual links and chain shall be as specified in Table 2, columns 4 to 8, and illustrated in EN 818-1:1996, Figure 1.Table 2 DimensionsDimensionsmm(1)(2)(3)(4)(5)(6)(7)(8)Nominal sizednMaterial diameter toleranceWeld diameterdsmax.PitchInternal width away from the weldw1min.External width over the weldw2max.pnpmaxpmin70,287,72121,620,49,125,980,328,82424,723,310,429,6100,4113030,929,11337130,5214,33940,237,816,948,1160,6417,64849,446,620,859,2180,919,85455,652,423,466,619120,95758,755,324,770,3201226061,858,22674221,124,266686428,681,4231,225,36971,166,929,985,1251,327,57577,372,832,592,5261,328,67880,375,733,896,2281,430,88486,581,536,4104321,635,29698,993,141,6118361,839,610811110546,81334024412012411652148452,349,513513913158,51675.3 Materials and heat treatment5.3.1 Quality of material5.3.1.1 GeneralWithin the limitations given in 5.3.1.2 to 5.3.1.4 the chain manufacturer shall select the type of steel to be used so that the finished chain, when suitably heat-treated, meets the mechanical properties specified in this part of EN 818.5.3.1.2 Type of steelThe steel used shall be produced by an electric process or by an oxygen blown process.5.3.1.3 DeoxidationThe steel shall be fully killed as defined in EN 10025:1990/A1:1993, be stabilized against strain age embrittlement and have an austenitic grain size of 5 or finer when tested in accordance with ISO 643.5.3.1.4 Chemical compositionTo ensure that chain is stabilized against strain age embrittlement during service the steel shall contain at least0,025 % aluminium.The steel shall contain no more sulfur and phosphorus content than the limits given in Table 3.Table 3 Sulfur and phosphorus contentElementMaximum mass content % as determined byCast analysisCheck analysisSulfur0,0250,030Phosphorus0,0250,030The silicon content shall be as specified in Table 4.NOTE The purpose of this requirement is to limit the detrimental effect when the chain is used in a galvanizing bath.Table 4 Silicon contentElementMass content % as determined byCast analysisCheck analysisSilicon0,12 to 0,300,15 to 0,355.3.2 Heat treatmentAll the chain shall be heat-treated in accordance with a) or b) before being subjected to the manufacturing proof force.a)Chain shall be hardened from a temperature above the AC3 point and tempered. The tempering temperature shall be at least 475 C.The tempering conditions shall be at least as effective as a temperature of 475 C maintained for a period of1 h.NOTE A method of verification is to test sample chains after they have been reheated to and maintained for 1 h at 475 C and then cooled to room temperature; following which they should conform in the finished condition to the requirements of 5.4.2 and .b) Alternatively the chain shall be normalized from a temperature above the AC3 point.5.4 Mechanical properties5.4.1 Manufacturing proof force (MPF)All the chain shall be subjected to the manufacturing proof force specified in Table 5, column 3 for the appropriate nominal size of chain.5.4.2 Breaking force (BF) and total ultimate elongation (A)Samples of chain in the finished condition shall have a breaking force at least equal to that specified in Table 5, column 4 for the appropriate nominal size of chain. On completion of the static tensile test the total ultimate elongation as defined in EN 818-1:1996 shall be not less than 25 %.5.4.3 Bend deflectionSingle link samples shall withstand the minimum deflection specified in Table 5, column 5 for the appropriate nominal size of chain and shall be free from visible defects.Table 5 Working load limits and test requirements12345Nominal size,dnmmWorking load limit,WLLtManufacturing proof force, MPFkNBreaking force, BFkNmin.Bend deflection, fmm min.70,7515,430,85,68120,140,26,4101,631,462,88132,6553,11061016480,41611318510220414195,611322715206,312625116227,515230418238166332182510196393202610,6212425212812,52464932232163226432636204078142940255031 010324531,56361 270366 Verification of safety requirements6.1 Qualification of personnelAll testing and examination shall be carried out by a competent person.6.2 Size of lot and selection of samplesThe size of the lot from which samples shall be selected shall be 400 m. An excess fraction of the length of lot shall be considered as a separate lot. Samples shall be selected as specified in EN 818-1.6.3 Manufacturing proof force, breaking force and total ultimate elongation6.3.1 Static tensile testThe testing machine and test procedure for the static tensile test shall be as specified in EN 818-1.6.3.2 Manufacturing proof force acceptance criteriaAll the chain shall sustain the manufacturing proof force specified in .6.3.3 Breaking force and total ultimate elongation acceptance criteriaOn completion of the static tensile test the requirements of 5.4.2 shall be met.6.4 Bend deflection6.4.1 Bend testThe test equipment and procedure shall be as specified in EN 818-1.Each single link sample shall be bent to the minimum deflection, f, as shown in Figure 1 and given in Table 5, column 5.Following the removal of the force, the link sample shall be examined.NOTE Where necessary a surface coating may be removed after the bend test to enable this examination to be carried out.Figure 1 Bend deflection f6.4.2 Bend deflection acceptance criteriaOn completion of the bend test the requirements of 5.4.3 shall be met.7 MarkingMarking shall be as specified in EN 818-1. The grade mark for the chain shall be “4”.8 Manufacturers certificateThe manufacturers certificate shall be as specified in EN 818-1.9 Instructions for useInstructions for use shall accompany the chain and shall be in accordance with the relevant clauses of prEN 818-6.Annex A (informative)Calculation of dimensions, working load limits and mechanical propertiesA.1 Dimensions and tolerancesA.1.1 In Table 2, column 2, the tolerances on material diameters are based on:a)4 % of the nominal size of chain for nominal sizes less than 18 mm;b) 5 % of the nominal size of chain for nominal sizes of 18 mm and over, values being rounded to 0,1 mm.A.1.2 The bases for calculation of dimensions in Table 2, columns 3 to 7, are as follows:Maximum diameter at the weldds max.= 1,1dnNominal pitchpn= 3dnMinimum pitch of chainpmin= 2,91dnMaximum pitch of chainpmax = 3,09dnMinimum internal width away from the weldw1= 1,3dnMaximum external width over the weldw2= 3,7dnThe dimensions given in Table 2 are full calculated values rounded to 0,1 mm for values up to 100 mm. Values equal to or greater than 100 mm are rounded to 1 mm.A.2 Working load limits and mechanical propertiesA.2.1 GeneralThe stresses used in the calculation of working load limits and mechanical properties in the formulae given in A.2.2 to A.2.4 are me
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