1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ICS 21.100.10 ISBN 0-626-17463-5 SANS 12129-2:2006Edition 1ISO 12129-2:1995Edition 1 SOUTH AFRICAN NATIONAL STANDARD Plain bearings Part 2: Tolerances on
4、 form and position and surface roughness for shafts, flanges and thrust collars This national standard is the identical implementation of ISO 12129-2:1995 and is adopted with the permission of the International Organization for Standardization. Published by Standards South Africa 1 dr lategan road g
5、roenkloof private bag x191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 12129-2:2006 Edition 1 ISO 12129-2:1995 Edition 1 Table of changes Change No. Date Scope Abstract Specifies tolerances on form and position as well as
6、the surface roughness of shafts, flanges and thrust collars as used in plain bearing units. Applicable to journal or thrust plain bearing units or to a combination of both, installed either horizontally or vertically. It is not applicable to crankshaft bearing units in combustion engines. Keywords b
7、earing collars, bearings, flanges, form tolerances, plain bearings, shafts (rotating), surface properties, tolerances of position. National foreword This South African standard was approved by National Committee StanSA TC 5120.02, Bearings, in accordance with procedures of Standards South Africa, in
8、 compliance with annex 3 of the WTO/TBT agreement. INTERNATIONAL STANDARD ISO 12129-2 First edition 1995-04-01 Plain bearings - Part 2: Tolerantes on form and Position and surface roughness for shafts, flanges and thrust collars Pahers lisses - Partie 2: Tokrances de forme et de position et rugosite
9、 de surface des arbres, collerettes et collets de butee Reference number ISO 12129-2:1995(E) ISO 12129=2:1995(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national Standards bodies (ISO member bodies). The work of preparing International Standards
10、 is normally carried out through ISO technical committees. Esch 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 p
11、art in the work. ISO 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 Sta
12、ndard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 12129-2 was prepared by Technical Committee ISO/TC 123, Plain bearings, Subcommittee SC 3, Dimensions, tolerantes and construction details. ISO 12129 consists of the following Parts, under the ge
13、neral title Plain bearings: - Part 7: Fits - Part 2: Tolerantes on form and position and surface roughness for shafts, flanges and thrust collars 0 ISO 1995 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electro
14、nie or mechanical, including photocopying and microfilm, without Permission in writing from the publisher. International Organization for Standardization Case Postale 56 l CH-121 1 Geneve 20 l Switzerland Printed in Switzerland INTERNATIONAL STANDARD 0 ISO ISO 12129=2:1995(E) Plain bearings - Part 2
15、: Tolerantes on form and Position and surface roughness for shafts, flanges and thrust collars 1 Scope This part of ISO 12129 specifies tolerantes on form and Position as well as the surface roughness of shafts, flanges and thrust collars as used in plain bearing units. lt is applicable to journal o
16、r thrust plain bearing units or to a combination of both, installed ei- ther horizontally or vertically. This patt of ISO 12129 is not applicable to crankshaft bearing units in combustion engines. 2 Normative references The following Standards contain provisions which, through reference in this text
17、, constitute provisions of this part of ISO 12129. 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 ISO 12129 are encouraged to investi- gate the possibility of applying the most recent edi- tions of
18、 the Standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 7902-1: -1, Hydrodynamit plain journal bearings under s teady-s ta te conditions - Circular cylindrical bearings - Part 1: Calcula tion procedure. ISO 7902-2: -J, Hydrodynamit pl
19、ain journal bearings under s teady-s ta te conditions - Circular cylindrical bearings - Part 2: Functions used in the calcuiation procedure. ISO 7902-3: -1, Hydrodynamit plain journal bearings under steady-sta te conditions - Circular cylindrical bearings - Part 3: Permissible operational parame- te
20、rs. ISO 12301: 1992, Plain bearings - Quality control techniques and inspection of geometrical and material quality charac teris tics. 3 General Specifications for use in thick-wall plain journal bearings are based on a minimum wall thickness di- ameter ratio greater than or equal to 0,ll (reference
21、 value). The reliability of a plain bearing is not only a function of the proper selection of material and fit, but de- pends in particular on the quality of the shafts, flanges and thrust collars used in the plain bearing unit. The spread of the accuracy grade is based on the minimum Iubricant film
22、 thickness h, in micrometers, calculated for each particular application in accordance with Parts 1 to 3 of ISO 7902. 4 Dimensions See figures 1 to 4 and table 1. The illustrations show plain bearings in the horizontal Position. 1) To be published. ISO 12129=2:1995(E) Figure 1 - Shaft for journal be
23、arings - A _- , I * / : , , ( 0 , , SI I / : , , , I , , I A d c Figure 2 - Shaft with two flanges for journal thrust bearings, capable of carrying load on both sides - B Figure 3 - Shaft with thrust collar for journal thrust bearings, capable of carrying load on both sides - C l concave Figure 4 -
24、Shaft with flange or thrust collar for journal thrust bearings, capable of carrying load on one side - D Table 1 ISO 12129=2:1995(E) Featurelparameter on drawing Lubricating film thickness Accuracy grade 5 10 20 30 h, Pm 5QQ 30 Roundness tolerante t, mm 0,004 I 0,006 0,Ol I 0,015 Cylindrical forml)
25、Straightness tolerante t2 mm 0,005 I 0,Ol 0,015 0,02 Parallelism tolerante t3 mm 0,015 0,02 0,03 0,04 Runout tolerante t4 mm 0,006 I 0,008 0,012 I 0,018 Flatness tolerante) t5 mm 0,006 I 0,008 0,012 0,018 Concentricity tolerante t6 mm 3) 3) 3) 3) Surface roughness4) R, Pm ( 4 1 w 1 0,63 l 03 R, Pm 1
26、 25 1 4 5 I 63 1) For reasons of measurement techniques and economic considerations, the cylindrical form has been toleranced for characteristics of roundness, straightness and parallelism. 2) The restrictive specification “not concave” on figures 2 to 4 shall be observed. 3) The concentricity toler
27、ante is a function of the specific operating conditions and thus is subject to agreement. 4) The specification of the surface roughness shall be based on R, or R, subject to agreement. 5 Design 6 Testing For reasons of production engineering, the curved transition on the shaft between the radial par
28、t and the axial part tan also be made as an undercut. Given the great number of possible bearing Seals, no details tan be indicated with regard to the area of the sealing Zone. The geometry and surface finish of the shafts, flanges and thrust collars shall be specified as a function of the bearing s
29、eal selected. Testing of the quality characteristics shall be carried out in accordance with ISO 12301. 7 Designation Designation of the tolerantes on form and Position as well as of the surface roughness of a shaft with two flanges at the Position of a journal thrust bearing ca- pable of carrying load on both sides (B) (sec figure2), accuracy grade 20: Plain bearing ISO 12129 - B20 Standards South AfricaThis s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .
