1、BS ISO 19690-1:2017Disc springsPart 1: CalculationBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS ISO 19690-1:2017 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 19690-1:2017. The UK participation in its preparation was entr
2、usted to TechnicalCommittee FME/9/3, Springs.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standard
3、s Institution 2017. Published by BSI Standards Limited 2017ISBN 978 0 580 88622 5ICS 21.160Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 March 2017.Amendments
4、/corrigenda issued since publicationDate Text affectedBS ISO 19690-1:2017 ISO 2017Disc springs Part 1: CalculationRessorts disques Partie 1: CalculINTERNATIONAL STANDARDISO19690-1First edition2017-03Reference numberISO 19690-1:2017(E)BS ISO 19690-1:2017ISO 19690-1:2017(E)ii ISO 2017 All rights reser
5、vedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intra
6、net, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.i
7、so.orgBS ISO 19690-1:2017ISO 19690-1:2017(E)Foreword iv1 Scope . 12 Normative references 13 Terms and definitions . 14 Symbols and units . 15 Dimensions and designation . 35.1 General . 35.2 Disc spring groups . 35.3 Dimensional series 46 Design formulae for springs . 46.1 General . 46.2 Test load 4
8、6.3 Coefficients used in calculation 46.4 Spring load 56.5 Design stresses 56.6 Spring rate . 66.7 Energy capacity of springs 67 Load characteristics 67.1 Load characteristics for a single disc spring . 67.1.1 Load/deflection curve . 67.1.2 Design and actual load characteristics 77.2 Load characteri
9、stics for stacks of disc springs 87.2.1 General 87.2.2 Stacking in parallel . 87.2.3 Stacking in series . 97.2.4 Stacking in parallel and series. 108 Design stresses 119 Types of loading .129.1 Static loading and moderate fatigue conditions 129.2 Dynamic loading . 12Bibliography .13 ISO 2017 All rig
10、hts reserved iiiContents PageBS ISO 19690-1:2017ISO 19690-1:2017(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical
11、committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with
12、the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for
13、 the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent righ
14、ts. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www .iso .org/ patents).Any trade name used in t
15、his document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World
16、Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html.This document was prepared by Technical Committee ISO/TC 227, Springs.A list of all the parts in the ISO 19690 series can be found on the ISO website.iv ISO 2017 All
17、 rights reservedBS ISO 19690-1:2017INTERNATIONAL STANDARD ISO 19690-1:2017(E)Disc springs Part 1: Calculation1 ScopeThis document specifies design criteria and features of disc springs, whether as single disc springs or as stacks of disc springs. It includes the definition of relevant concepts, as w
18、ell as design formulae, and covers the fatigue life of such springs.2 Normative referencesThe following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated r
19、eferences, the latest edition of the referenced document (including any amendments) applies.ISO 16249, Springs SymbolsISO 26909, Springs Vocabulary3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 26909 apply.ISO and IEC maintain terminological database
20、s for use in standardization at the following addresses: ISO Online browsing platform: available at www .iso .org/ obp IEC Electropedia: available at www .electropedia .org4 Symbols and unitsFor the purposes of this document, the symbols and units given in ISO 16249 and Table 1 apply. ISO 2017 All r
21、ights reserved 1BS ISO 19690-1:2017ISO 19690-1:2017(E)Table 1 Symbols and units for design calculationSymbol Unit ParameterC1, C2, C3, C4 coefficientsD mm external diameter of springD0mm diameter of centre of rotationd mm internal diameter of springE N/mm2modulus of elasticity of material(carbon ste
22、el and carbon alloy steel: 206 000 N/mm2)(other materials: respective modulus of elasticity of material )F N spring loadFcN design spring load when spring is in the flattened positionFGN spring load at the time of combining springsFtN spring test load at HtHtmm height of spring when measuring spring
23、 load, Ht= H0 0,75 h0H0mm free height of springh0mm initial cone height of springs without flat bearings, h0= H0 th0,fmm initial cone height of springs with flat bearings, h0,f= H0 tfi number of springs combined in seriesk1, k2 coefficientsL0mm free height at the time of combining springsN number of
24、 cycles for fatigue lifen number of springs piled in parallelOM point at upper surface of the spring perpendicular to the centre line at point PP theoretical centre of rotation of disc cross sectionR N/mm spring rater mm chamfer radius at edges mm deflection of springsGmm deflection of stackt mm thi
25、ckness of springtfmm reduced thickness of single disc spring with flat bearingsV mm length of lever armsVfmm length of lever arms with flat bearingsW Nmm energy capacity of springs ratio of external diameter to internal diameter Poissons ratio of materialOMN/mm2stress at position OM IN/mm2stress at
26、position I IIN/mm2stress at position II IIIN/mm2stress at position III IVN/mm2stress at position IVNOTE N/mm2= MPa2 ISO 2017 All rights reservedBS ISO 19690-1:2017ISO 19690-1:2017(E)5 Dimensions and designation5.1 GeneralFigure 1 illustrates a single disc spring, including the relevant positions of
27、loading.a) Without flat bearings: group 1 and group 2b) With flat bearings: group 3KeyD external diameter of spring t thickness of springD0diameter of centre of rotation V length of lever armsd internal diameter of spring Vflength of lever arms with flat bearingsF spring load I position IH0free heig
28、ht of spring II position IIOM point at upper surface of the spring perpendicular to the centre line at point PIII position IIIP theoretical centre of rotation of disc cross section IV position IVr chamfer radius at edgetfreduced thickness of single disc spring with flat bearingsFigure 1 Single disc
29、spring (sectional view), including the relevant positions of loading5.2 Disc spring groupsTable 2 shows disc spring groups. ISO 2017 All rights reserved 3BS ISO 19690-1:2017ISO 19690-1:2017(E)Table 2 Disc spring groupsGroup t (mm) With flat bearings and reduced thickness1 0,2 t 0,75, the actual curv
30、e will deviate more and more from the design curve because the disc springs will be in contact with each other or with the support plate, which results in a steady reduction in the length of the lever arm. ISO 2017 All rights reserved 7BS ISO 19690-1:2017ISO 19690-1:2017(E)Key1 design curve2 actual
31、curve3 s = 0,75 h0(h0is the initial cone height of springs without flat bearings)F spring loads deflection of springFigure 3 Example of actual and design spring load/deflection curves7.2 Load characteristics for stacks of disc springs7.2.1 GeneralFor springs, various load characteristics can be obta
32、ined from the various combinations. When the spring is used in a stack and applied to a load, it should be guided by an inner guide or an outer guide to keep it in position. It is preferable to use an inner guide, but an outer guide is acceptable. When using the guide, a clearance between the spring
33、 and the guide shall be made. The amount of clearance should be agreed between customer and supplier.In the case of springs stacked in series, where h0/t 1,25, it may be assumed that the deflection of the single disc springs will not be uniform, which may cause a failure.7.2.2 Stacking in parallelIn
34、 the case of stacking disc springs in parallel as shown in Figure 4, the spring load will be in direct proportion to the number of single disc springs making up the stack. The spring load, the deflection and free height are calculated using Formula (18) to Formula (20):FG= n F (18)sG= s (19)L0= H0+
35、(n 1) t (20)8 ISO 2017 All rights reservedBS ISO 19690-1:2017ISO 19690-1:2017(E)NOTE In the case of springs with flat bearings, tfis substituted for t.KeyF spring loadFcdesign spring load when spring is in the flattened positionH0free height of springh0initial cone height of springs without flat bea
36、ringsL0free height at the time of combining springsn number of springs piled in parallels deflection of springt thickness of springFigure 4 Variations in load/deflection curves when stacking springs in parallel7.2.3 Stacking in seriesIn the case of stacking disc springs in series, as shown in Figure
37、 5, the deflection will be in direct proportion to the number of single disc springs making up the stack. The spring load, the deflection and free height are calculated using Formula (21) to Formula (23):FG= F (21)sG= i s (22)L0= i H0(23) ISO 2017 All rights reserved 9BS ISO 19690-1:2017ISO 19690-1:
38、2017(E)KeyF spring loadFcdesign spring load when spring is in the flattened positionH0free height of springh0initial cone height of springs without flat bearingsi number of springs combined in seriesL0free height at the time of combining springss deflection of springt thickness of springFigure 5 Var
39、iations in load/deflection curves when stacking springs in series7.2.4 Stacking in parallel and seriesIn the case of stacking disc springs in parallel and series, as shown in Figure 6, the spring load, the deflection and free height are calculated using Formula (24) to Formula (26):FG= n F (24)sG= i
40、 s (25)L0= H0+ (n 1) t i (26)NOTE In the case of springs with flat bearings, tfis substituted for t.10 ISO 2017 All rights reservedBS ISO 19690-1:2017ISO 19690-1:2017(E)KeyF spring loadFcdesign spring load when spring is in the flattened positionh0initial cone height of springs without flat bearings
41、i number of springs combined in seriesL0free height at the time of combining springsn number of springs piled in parallels deflection of springFigure 6 Variations in load/deflection curves when stacking springs in parallel and series8 Design stressesSince there are residual stresses in the spring as
42、 a result of the manufacturing process used, the results obtained from Formula (10) to Formula (14) do not reflect the actual values involved, but rather any nominal values. Thus, all information relating to stress in this document represents these nominal values.An estimate of the permissible free
43、overall height of the spring, H0, may be based on a determination of the design stress, OM, which should be about equal to the tensile strength.The most important parameter for springs subjected to fatigue loading is the calculated tensile stress on the lower side of a single disc spring. The positi
44、on most vulnerable to fatigue failure will be either the lower inner edge, position II, or the lower outer edge, position III (see Figure 1 and Figure 7), depending on the ratios D/d = , h0/t and s/h0.This is illustrated in Figure 7 and applies to springs with or without flat bearings.Since the rati
45、o s/h0is a factor of influence with regard to the level of tensile stress at positions II and III, it is recommended, for the area between these positions, that IIand IIIbe determined in accordance with the formulae given in 6.5. ISO 2017 All rights reserved 11BS ISO 19690-1:2017ISO 19690-1:2017(E)K
46、eyh0/t ratio of initial cone height of spring to thickness ratio of external diameter to internal diameter, = D/dNOTE In the case of springs with flat bearings, C4 h0,f/tfis substituted for h0/t.Figure 7 Relevant positions of loading for springs subject to fatigue loading9 Types of loading9.1 Static
47、 loading and moderate fatigue conditionsSprings shall be deemed to be subject to static loadinga) where this is the only type of loading and where it does not change, andb) if they are deemed to be subject to moderate fatigue conditions where the loading does change, but only infrequently, and where
48、 the number of cycles to which they are exposed during their intended use is less than 104.9.2 Dynamic loadingDepending on the required minimum number of loading cycles without failure, N, a differentiation is made betweena) springs with a limited fatigue life, i.e. those which are able to withstand
49、 104 N 2 106cycles, andb) springs with a high fatigue life, i.e. those which are able to withstand 2 106cycles or more without failure.Where springs are expected to withstand substantially more than 2 106cycles, the manufacturer shall be consulted.12 ISO 2017 All rights reservedBS ISO 19690-1:2017ISO 19690-1:2017(E)Bibliography1 DIN 2092, Disc springs Calculation2 DIN 2093, Disc springs Quality specifications Dimensions3 JIS B 2706,
