ISO INTERNATIONAL STANDARD 7146-1 Second edition 2019-05 Plain bearings Appearance and characterization of damage to metallic hydrodynamic bearings Part 1: General Paliers lisses - Aspect et caractérisation de I'endommagement des paliers métalliques a couche lubrifiante fluide- Partie 1: Géneralités Reference number ISO 7146-1:2019(E) ISO @ IS0 2019 IS0 7146-1:2019(E) COPYRIGHTPROTECTEDDOCUMENT @ ISO 2019 All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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 address below or Iso's member body in the country of the requester. ISO copyright office CP 401 : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +4122 749 0111 Fax: +41 22 749 09 47 Email: copyright@iso.org Website: www.iso.org Published in Switzerland ii @ IS0 2019 - All rights reserved IS0 7146-1:2019(E) Contents Page Foreword ..V Introduction. ..vi 1 Scope. 2 Normative references 3 Terms and definitions 4 Descriptions, causes and features of damage ..2 4.1 Damage. .2 4.1.1 General. .2 4.1.2 Indicators of damage 2 .2 4.2 Damage causes... 4.3 Damage appearances. 2 4.4 Damage characterization .3 4.4.1 General. 3 4.4.2 Static overload .3 4.4.3 Dynamic overload 3 4.4.4 Wear by friction. 3 4.4.5 Overheating. 3 4.4.6 Insufficient lubrication (starvation) 3 4.4.7 Contamination .3 4.4.8 Cavitation erosion. 3 4.4.9 Electroerosion. .3 4.4.10 Hydrogen diffusion. 4 4.4.11 Bond failure ..4 4.5 Relationship between damage appearance and damage characterizations .4 5 Guidelines for damage analysis .5 5.1 General .7 5.2 Step 1 .7 5.3 Step 2. 1 5.4 Step 3. .7 5.5 Step 4. .7 5.6 Step 5 7 6 Damage to the bearing surface - Damage characteristics, typical damage appearances and possible damage causes. 7 6.1 General 7 6.2 Static overload. .8 6.2.1 Typical damage appearances ..8 6.2.2 Possible damage causes. ..8 6.2.3 Typical examples ..8 6.3 Dynamic overload. .9 6.3.1 Typical damage appearances .9 6.3.2 Possible damage causes. .9 6.3.3 Typical examples .9 6.4 Wear by friction. .15 6.4.1 Typical damage appearances. .15 6.4.2 Possible damage causes. .16 6.4.3 Typical examples ..16 6.5 Overheating .18 6.5.1 Typical damage appearances. ..18 6.5.2 Possible damage causes. ..19 6.5.3 Typical examples ..19 6.6 Insufficient lubrication (starvation) .21 6.6.1 Typical damage appearances. 21 @ IS0 2019 - All rights reserved ii