INTERNATIONAL STANDARD IS0 7905 4 First edition 1995 02 01 Corrected and reprinted 1996 04 01 Plain bearings Bearing fatigue Part 4 Tests on half bearings of a metallic multilayer bearing material Pal[.]
IS0 INTERNATIONAL STANDARD 7905-4 First edition 1995-02-01 Corrected and reprinted 1996-04-01 `,`,`,,,,`,,,`,,``,``,```,-`-`,,`,,`,`,,` - Plain bearings - Bearing fatigue - Part 4: Tests on half-bearings bearing material of a metallic multilayer Paliers Asses - - Fatigue des paliers Partie 4: Essais sur demi-coussinets multicouche en matkriau antifriction m&aliique Reference number IS0 7905-4:1995(E) Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Foreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member bodies) The work of preparing International Standards is normally carried out through IS0 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-governmental, in liaison with ISO, also take par-t in the work IS0 collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization Draft International Standards adopted by the technical committees are circulated to the member bodies for voting Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote International Standard IS0 7905-4 was prepared by Technical Committee ISO/TC 123, Plain bearings, Subcommittee SC 2, Materials and lubricants, their properties, characteristics, test methods and testing conditions `,`,`,,,,`,,,`,,``,``,```,-`-`,,`,,`,`,,` - IS0 7905 consists of the following bearings - Bearing fatigue: parts, under the general - Part I: Plain bearings in test rigs and in applications of hydrodynamic lubrication - Part 2: Test with a cylindrical - Part 3: Test on plain strips of a metallic - Part 4: Tests on half-bearings terial Annex A forms an integral information only specimen title Plain under conditions of a metallic bearing material multilayer of a metallic bearing material multilayer bearing part of this part of IS0 7905 Annex ma- B is for IS0 1995 All rights reserved Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher International Organization for Standardization Case Postale 56 l CH-1211 Geneve 20 l Switzerland Printed in Switzerland ii Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS INTERNATIONAL STANDARD Plain bearings - Beari.ng fatigue `,`,`,,,,`,,,`,,``,``,```,-`-`,,`,,`,`,,` - Part 4: Tests on half-bearings material IS0 7905-4:1995(E) IS0 of a metallic multilayer Scope This part of IS0 7905 specifies a method for the determination of the endurance limit in fatigue of halfbearings of multilayer bearing materials Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this part of IS0 7905 At the time of publication, the editions indicated were valid All standards are subject to revision, and parties to agreements based on this part of IS0 7905 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below Members of IEC and IS0 maintain registers of currently valid International Standards IS0 4386-3:1992, plain bearings testing Plain bearings - Metallic Part 3: Non-destructive multilayer penetrant IS0 7905-3:1995, Plain bearings - Bearing fatigue - Part 3: Test on plain strips of a metallic multilayer bearing material Test specimens The use the the test specimens shall be half-bearings ready for Normally, as a result of the loading conditions, major stresses are located in the crown area of bearing Care should be taken before and during Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS bearing the test not to damage the surface mechanically or by corrosion The advantage of this method is the presence of residual stress associated with the bearing manufacturing process - Test methods The test principle is illustrated in figure The specimens shall be clamped at one end and loaded at the other end by force or displacement applied radially at the relief parting line runout The load shall fluctuate from tension to compression within the running surface Additionally a tensile or compressive prestress may be applied in order to evaluate dependency upon mean stress The test equipment is preferably located in a chamber containing a lubricant at fixed levels of temperature to + “C Alternatively tests may be conducted in air at fixed levels of temperature f “C Bending stress may be measured by a strain gauge on the back of the bearing at the crown (midperipheral length) The required stress in the lining can be calculated if the steel and lining thicknesses and Young’s modulii are known Alternatively, the radial force at the clamping end F can be measured by load cell or calculated from cantilever beam theory and the value of stress in the lining calculated according to annex A The values are critically dependent upon the lining and steel thickness which shall be determined by microsection after the tests The test frequency shall have a range of 50 Hz to 80 Hz Crack detection shall be performed by dye penetrant method (see IS0 4386-3) or by microscope Q IS0 IS0 7905-4:1995(E) F = F + F, x sin (w x t) or s = B + sA x sin (w x t) 1) 2) 3) 4) Frame Hydraulic cylinder Connecting shaft Seal 5) 6) 7) 8) Sample receptacle Strip heater Testing fluid Half bearing Figure - Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS 9) IO) 11) 12) Hinged clamping beam Load cell Rollers on radial line Fulcrum clamping beam Test principle `,`,`,,,,`,,,`,,``,``,```,-`-`,,`,,`,`,,` - IS0 7905-4:1995(E) Q IS0 The amplitude shall be controlled by force (F) or displacement (4 For detecting crack initiation in thicker layers, the reduction of gauge strain may be used to determine failure onset, see IS0 7905-3 Evaluation and presentation of results The endurance limit stresses should be presented in the form of a,,-&’ curves at a predetermined temperature (+ “Cl against a detailed description of the bearing material Normally cr,,-N curve testing is ter- minated for practical considerations at 50 x IO” stress cycles The endurance limit stress may be quoted at: a specified number of cycles, e.g x IO”, IO x IO! 25 x O6 or 50 x 06 A specimen without failure during fatigue testing to a specified endurance should be identified in the report Due to the scatter of test results normally experienced and the statistical nature of the fatigue limit, it is recommended that the results be evaluated on the basis of a statistical method Another presentation of the endurance limit stress may be effected by means of the Haigh diagram which plots stress amplitude against mean stress Metallographic examination will provide detailed evidence of the damage mechanism, corrosive attack and diffusion resulting from thermal effects `,`,`,,,,`,,,`,,``,``,```,-`-`,,`,,`,`,,` - Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS IS0 7905-4:1995(E) Q IS0 Annex A (normative) Evaluation A.1 Evaluation of stresses A half-bearing system is described in figureA by radial dimensions r4, thickness s1 and related to Young’s modulus I& = 50 x lo3 MPa and to nominal stress flnom vz `,`,`,,,,`,,,`,,``,``,```,-`-`,,`,,`,`,,` - E2 ~norn = = ~ b x s2 *4 r4 - f-2 ‘3 E; = E2/50 x O3 Figure A.1 - A.2 Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS Definition Unit Al coefficient of stress at the bearing backing - ‘1 ,i coefficients at the outside of the bearing back with i = 0, 1, - A2 coefficient of stress at the surface of the lining - %,i coefficients at the surface of the lining with i = 0, 1, - b bearing width mm coefficient of stress at the bearing backing - bl,i coefficients at the outside of the bearing back with i = 0, 1, - B2 coefficient of stress at the surface of the lining - b2.i coefficients at the surface of the lining with i = 0, 1, - E Young’s E’ dimensionless Young’s modulus, E’ = Ed4.0 Young’s modulus, steel bearing backing, E, = 210 x O3 El modulus E2 Young’s E2.0 Young’s modulus E2,,=50x103 =% F Young’s Half-bearing system The solution is given in figureA for a two-layer bearing It is self-explanatory An approximation for the stress in the overlay of a three-layer bearing is also given in figureA.2 Symbols Symbol GxFxT s'=2x r4 - r3 r4 + '3 s; of stress modulus, modulus, MPa lining MPa Pa for figureA.2, overlay MPa Pa radial force N r2 radius of interface between bearing backing and lining the mm ‘3 radius of running surface thickness negligible) (overlay mm ‘4 outer radius of bearing steel back mm IS0 ISO 7go5-4:1995E) Definition total thickness of bearing dimensionless see figureA total thickness, thickness of steel backing dimensionless steel backing thickness, see figureA Unit mm mm - time S stress dimensionless endurance stress, CT*= a/a,,, limit stress dnom nominal stress Ql stress at the outside of the bearing back stress at the surface of the lining dimensionless face stress, lining sur- stress in overlay dimensionless stress, overlay To calculate related dimensions See figureA.l S* = 0.06 A.3.2 s; = 0,8 To calculate nominal E’ = I,38 stress See figureA.l anom =lll,l MPa A.3.3 To calculate and b or read the coefficients Pa Pa dimensionless stress at the bearing steel back a2 Pa - A.3.1 MPa MPa Pa - See figure A.2 Running surface: u2,, = 0,016 c&J, = 0,495 CzyJ= - 0,086 b2,0 = 0,033 b2,, = 0,339 b2,2 = - 0,,079 u,,~ = 1,572 a,,, = - 0,296 a,,2 = 0.049 b,,o = - 0,440 b,,, = - 0,095 b,,2 = 0,034 Bearing back: A.3.4 To calculate the coefficients A and B Running surface: A, = 0,535 A.3 Example Given data for a half-bearing: B2 = 0,350 Bearing back: A, = 1,257 B, = - 0,506 b=30mm E, = 210 x IO3 MPa A.3.5 To calculate the dimensionless E2=69x IO3 MPa Running surface: a; = 0,556 &=22x 1O”MPa Bearing back: a; = 1,227 F=lOO stress N r2 = 49, IO mm A.3.6 To calculate real stress r, = 48.52 mm Running surface: a2 = 61,8 MPa r4 = 51,50 mm Bearing back: CT,= 136,3 MPa It is assumed that since the overlay (PbSnll) is relatively thin (0,02 mm) it does not affect the stresses in the other layers Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS A.3.7 Approximation a3 = 19,7 MPa for stress in overlay `,`,`,,,,`,,,`,,``,``,```,-`-`,,`,,`,`,,` - Symbol LZ IS0 7905-4: 1995(E) Running (Lining) surface Back of the bearing I 01 z u -1 -2 `,`,`,,,,`,,,`,,``,``,```,-`-`,,`,,`,`,,` - 0.6 I 0.2 0.4 _ o -0.2 -0,0 0,s a2,,=1,8127-4,181 u2,, = - 0,942 0.0 0,-l s,* - 0.6 0.9 a ,, = 5,386 x s; - 3,906 x si2 u,,,=0,1525-l.1544xs;+1,0703xs;2 9,0=1,551 I-3.2821 &,, = - 1,994 &,2 = 0,659 + 6,592 - 5,709 ul,l = - 7,101 a 1.2 = 2,674 xs;+1,7309xs;' - 2,255 0.7 x s; + ,I 76 x sT2 + 13,962 - 5.799 x s; - 6,819 x s; + 3,147 x s; - 4,593 x s;~ x s;* x s; + 1,664 b,,, = 2,209 - 6,615 x s; + 4,668 B, = b2,0 + b2,, x E; + & B, = b,,, + b,,, x E; + b,,2 x E;’ x EG2 a; = A, + B, x S* 02 + u1,1 x E; + u,,~ x E;’ a; = A, + B, x s* u, = u; x unom x ~n0m Approximation for stress in overlay: u3 = + x ,?%$!+ Figure A.2 - Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS x s;~ Stress evaluation x s;' b,,2 = - 0,590 + 1,923 x s; - 1,428 x s;~ A, = q = x s;~ b,,, = - 2,673 + 5,750 x s; + 3,697 x s;’ = %,o+ ~2,~x E; + a2.2 x -G2 Q2 0.8 s,* - 2xs;+2,4186xs;* + 4,921 0.6 0,s in two- and three-layer bearings 0.9 IS0 7905-4:1995(E) Annex B (informative) Bibliography [I] IS0 354811978, checking Plain bearings [Z] IS0 4378-l :1983, Plain bearings and their properties `,`,`,,,,`,,,`,,``,``,```,-`-`,,`,,`,`,,` - Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS - Thin-walled half bearings - Terms, definitions - Dimensions, and classification - Part tolerances and methods 7: Design, bearing of materials `,`,`,,,,`,,,`,,``,``,```,-`-`,,`,,`,`,,` - IS0 7905-4:1995(E) ICS 21.100.10 Descriptors: bearings, plain bearings, Price based on pages Copyright International Organization for Standardization Provided by IHS under license with ISO No reproduction or networking permitted without license from IHS tests, fatigue tests