BS ISO 14728-2-2017 Rolling bearings Linear motion rolling bearings Static load ratings《滚动轴承 线性运动滚动轴承 静态荷载额定值》.pdf

1、BS ISO 14728-2:2017Rolling bearings Linearmotion rolling bearingsPart 2: Static load ratingsBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS ISO 14728-2:2017 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 14728-2:2017. It sup

2、ersedes BS ISO 14728-2:2004 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee MCE/7, Rolling bearings.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the n

3、ecessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2017.Published by BSI Standards Limited 2017ISBN 978 0 580 87022 4 ICS 21.100.20 Compliance with a British Standard cannot confer immunity from legal obligations.This British Stand

4、ard was published under the authority of the Standards Policy and Strategy Committee on 28 February 2017.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 14728-2:2017 ISO 2017Rolling bearings Linear motion rolling bearings Part 2: Static load ratingsRoulements Rouleme

5、nts mouvement linaire Partie 2: Charges statiques de baseINTERNATIONAL STANDARDISO14728-2Second edition2017-02Reference numberISO 14728-2:2017(E)BS ISO 14728-2:2017ISO 14728-2:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Un

6、less 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 intranet, without prior written permission. Permission can be requested from either ISO at the

7、 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.iso.orgBS ISO 14728-2:2017ISO 14728-2:2017(E)Foreword ivIntroduction v1 Scope . 12 Normati

8、ve references 13 Terms and definitions . 14 Symbols 75 Basic static load ratings 75.1 Linear ball bearings 75.1.1 Recirculating linear ball bearings, sleeve type, with or without raceway grooves 75.1.2 Recirculating linear ball bearings, linear guideway, carriage type . 85.1.3 Non-recirculating line

9、ar ball bearings, linear guideway, deep groove and four-point-contact types . 95.2 Linear roller bearings 105.2.1 Recirculating linear roller bearings, linear guideway, carriage type .105.2.2 Non-recirculating linear roller bearings, linear guideway, flat, V-angle and crossed roller types 106 Static

10、 equivalent load .107 Static load safety factor 10Bibliography .11 ISO 2017 All rights reserved iiiContents PageBS ISO 14728-2:2017ISO 14728-2:2017(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work

11、of preparing International Standards is normally carried out through ISO technical 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-government

12、al, in liaison with ISO, also take part in the work. ISO collaborates closely with 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 I

13、SO/IEC Directives, Part 1. In particular the different approval criteria needed for 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 possi

14、bility that some of the elements of this document may be the subject of patent rights. 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

15、 patent declarations received (see www .iso .org/ patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well a

16、s information about ISOs adherence to the World 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 4, Rolling bearings, Subcommittee SC 8, Load ratings and lif

17、e.This second edition cancels and replaces the first edition (ISO 14728-2:2004), of which it constitutes a minor revision with the following changes: improvement of Figures 2, 4, 8 and 9; correction of formula for k0iin Formula (1); alignment with the latest drafting rules.A list of all parts in the

18、 ISO 14728 series can be found on the ISO website.iv ISO 2017 All rights reservedBS ISO 14728-2:2017ISO 14728-2:2017(E)IntroductionIt is often impractical to establish the suitability of a linear motion rolling bearing selected for a specific application by testing. The following procedures have pro

19、ved to be an appropriate and convenient substitute for testing: life calculation with dynamic load (ISO 14728-1); static load safety factor calculation with static load (ISO 14728-2).Permanent deformation appears in rolling elements and raceways of rolling bearings under static loads of moderate mag

20、nitude and increases gradually with increasing load.It is often impractical to establish whether the deformation appearing in a bearing in a specific application is permissible by testing the bearing in that application. Other methods are therefore required to establish the suitability of the bearin

21、g selected.Experience shows that a total permanent deformation of 0,000 1 of the rolling element diameter, at the centre of the most heavily loaded rolling element/raceway contact, can be tolerated in most bearing applications without the subsequent bearing operation being impaired. The basic static

22、 load rating is, therefore, given a magnitude such that approximately that degree of deformation occurs when the static equivalent load is equal to the load rating.Tests in different countries indicate that a load of the magnitude in question may be considered to correspond to a calculated contact s

23、tress of 5 300 MPa for recirculating linear ball bearings, sleeve type, 4 200 MPa to 4 600 MPa for recirculating linear ball bearings, linear guideway type (see 3.9 and Table 1), 4 200 MPa to 4 600 MPa for non-recirculating linear ball bearings (see 3.9 and Table 1), and 4 000 MPa for linear roller

24、bearings,at the centre of the most heavily loaded rolling element/raceway contact. The formulae and factors for the calculation of the basic static load ratings are based on these contact stresses.The permissible static equivalent load may be smaller than, equal to or greater than the basic static l

25、oad rating, depending on the requirements for smoothness of operation and friction, as well as on actual contact surface geometry. Bearing users without previous experience of these conditions should consult the bearing manufacturers. ISO 2017 All rights reserved vBS ISO 14728-2:2017BS ISO 14728-2:2

26、017Rolling bearings Linear motion rolling bearings Part 2: Static load ratings1 ScopeThis document specifies methods of calculating the basic static load rating, static equivalent load and static safety factor for linear motion rolling bearings manufactured from contemporary, commonly used, high qua

27、lity, hardened bearing steel in accordance with good manufacturing practice and basically of conventional design with regard to the shape of the rolling contact surfaces.This document is not applicable to designs where the rolling elements operate directly on the slide surface of the machine equipme

28、nt, unless that surface is equivalent in all respects to the raceway of the linear motion rolling bearing component it replaces.2 Normative referencesThere are no normative references in this document.3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 76

29、 and ISO 5593, and the following apply.ISO and IEC maintain terminological databases for use in standardization at the following addresses: IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp3.1recirculating linea

30、r ball bearing, sleeve type, with or without raceway groovesbasically cylindrical sleeve provided with a number of closed loops of recirculating balls designed to achieve linear rolling motion along a hardened cylindrical shaftNote 1 to entry: See Figure 1.Note 2 to entry: The raceways in the sleeve

31、 can be designed cylindrical as well as steel inserts with raceway grooves parallel to the axis.INTERNATIONAL STANDARD ISO 14728-2:2017(E) ISO 2017 All rights reserved 1BS ISO 14728-2:2017ISO 14728-2:2017(E)Figure 1 Recirculating linear ball bearing, sleeve type3.2recirculating linear ball (or rolle

32、r) bearing, linear guideway, carriage typelinear ball (or roller) bearing provided with a number of symmetrically arranged, closed loops of recirculating balls (or rollers) designed to achieve linear rolling motion along a hardened guideway furnished with adequate racewaysNote 1 to entry: See Figure

33、 2.Figure 2 Recirculating linear ball (or roller) bearing, linear guideway, carriage type2 ISO 2017 All rights reservedBS ISO 14728-2:2017ISO 14728-2:2017(E)3.3non-recirculating linear ball bearing, linear guideway, deep groove typelinear bearing with balls as rolling elements, each ball having two

34、points of contactNote 1 to entry: See Figure 3.Note 2 to entry: The cross-sectional radii of the raceway grooves in the two guideways are equal and may lie between 0,52 Dwand infinity.Figure 3 Non-recirculating linear ball bearing, linear guideway, deep groove type3.4non-recirculating linear ball be

35、aring, linear guideway, four-point-contact typelinear bearing with balls as rolling elements, each ball having four points of contactNote 1 to entry: See Figure 4.Note 2 to entry: The cross-sectional radii of the raceway grooves for the four points of contact in the two guideways are equal and may l

36、ie between 0,52 Dwand infinity.Figure 4 Non-recirculating linear ball bearing, linear guideway, four-point-contact type ISO 2017 All rights reserved 3BS ISO 14728-2:2017ISO 14728-2:2017(E)3.5non-recirculating linear roller bearing, linear guideway, flat typelinear bearing with needle rollers or cyli

37、ndrical rollers as rolling elementsNote 1 to entry: See Figure 5.Figure 5 Non-recirculating linear roller bearing, linear guideway, flat type3.6non-recirculating linear roller bearing, linear guideway, V-angle typelinear bearing with guideways designed as parts of a V with a 90 angleNote 1 to entry:

38、 See Figure 6.Note 2 to entry: Needle rollers or cylindrical rollers are used as rolling elements.Figure 6 Non-recirculating linear roller bearing, linear guideway, V-angle type4 ISO 2017 All rights reservedBS ISO 14728-2:2017ISO 14728-2:2017(E)3.7non-recirculating linear roller bearing, linear guid

39、eway, crossed roller typelinear bearing with cylindrical rollers arranged in a crossed roller constructionNote 1 to entry: See Figure 7.Figure 7 Non-recirculating linear roller bearing, linear guideway, crossed roller type3.8static safety factorratio between the basic static load rating and the stat

40、ic equivalent load giving the margin of safety against inadmissible permanent deformation on rolling elements and raceways3.9basic static load rating of a linear motion rolling bearingstatic load which corresponds to a calculated contact stress maxat the centre of the most heavily loaded rolling ele

41、ment or raceway contactNote 1 to entry: For this contact stress, a total permanent deformation of rolling element and raceway occurs which is approximately 0,000 1 of the rolling element diameter. For a recirculating linear ball bearing, sleeve type: max= 5 300 MPa; For a recirculating linear ball b

42、earing, linear guideway type: see Table 1; For a non-recirculating linear ball bearing: see Table 1; For a linear roller bearing: max= 4 000 MPa. Table 1 Contact stress, maxrg(mm)0,52 Dw0,53 Dw0,54 Dw0,55 Dw0,56 Dw0,57 Dw0,58 Dw0,59 Dw0,6 Dwmax(MPa)4 200 4 250 4 300 4 350 4 400 4 450 4 500 4 550 4 6

43、003.10static equivalent loadstatic load that causes the same contact stress at the centre of the most heavily loaded rolling element or raceway contact as the stress that occurs under the actual load conditions ISO 2017 All rights reserved 5BS ISO 14728-2:2017ISO 14728-2:2017(E)3.11direction of load

44、direction of load applied for load rating calculationNote 1 to entry: For calculation of basic static load ratings, the direction of the load is defined for all linear motion bearings as shown by the arrows in Figure 8.Rolling bearing defined in3.1 3.2 3.4 3.7Figure 8 Direction of load3.12pitch diam

45、eterdiameter of the circle containing the centres of the balls in contact with the raceways, in a cross-sectional plane perpendicular to the bearing axis3.13nominal contact angleangle between the direction of load on the linear bearing and the nominal line of action of the resultant of the forces tr

46、ansmitted by a bearing raceway member to a rolling elementNote 1 to entry: See Figure 9.Figure 9 Nominal contact angle6 ISO 2017 All rights reservedBS ISO 14728-2:2017ISO 14728-2:2017(E)4 SymbolsFor the purposes of this document, the symbols given in ISO 76, ISO 15241 and Table 2 apply.Table 2 Symbo

47、ls, terms and unitsSymbol Term UnitC0Basic static load rating NDpwPitch diameter of ball rows mmDwBall diameter mmDweRoller diameter applicable in the calculation of load ratings mmF Load on bearing Nf0Factor which depends on the geometry of the bearing components and on the applicable stress level1

48、iNumber of rows of balls or rollers applicable in the calculation of load ratingsNOTE In the case of recirculating linear bearings, sleeve type, it is the total number of rows of balls.1itNumber of load-carrying rows of balls in loaded zone 90 j +90 of recirculating linear ball bearings, sleeve type

49、, with or without raceway grooves, applicable in the calculation of load ratings1k0FStatic load factor 1k0iLoad factor that depends on number of rows of balls in a recirculating ball bearing, sleeve type 1LweRoller length applicable in the calculation of load ratings mmP0Static equivalent load NrgCross-sectional radius of the raceway groove on guideway mmS0Static load safety factor 1Z Number of balls or rollers in one row 1ZtNumber of load-carrying balls or rollers in one row appli