1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 12046:2012Synchronous belt drives Automotive belts Determination of physicalpropertiesBS ISO 12046:2012 BRITISH STANDARDNational forewordThis British Standard is the UK im
2、plementation of ISO 12046:2012.The UK participation in its preparation was entrusted to TechnicalCommittee MCE/10, Belts 43.060.10Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strateg
3、y Committee on 31 March 2012.Amendments issued since publicationDate Text affectedBS ISO 12046:2012 ISO 2012Synchronous belt drives Automotive belts Determination of physical propertiesTransmissions synchrones par courroies Courroies pour la construction automobile Dtermination des caractristiques p
4、hysiquesINTERNATIONAL STANDARDISO12046Second edition2012-03-01Reference numberISO 12046:2012(E)BS ISO 12046:2012ISO 12046:2012(E)ii ISO 2012 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2012All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utili
5、zed in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41
6、22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 12046:2012ISO 12046:2012(E) ISO 2012 All rights reserved iiiContents PageForeword iv1 Scope 12 Normative references . 13 Principle . 14 Test methods 15 General conditions for testing . 25.1 Standard environmental condit
7、ions . 25.2 Standard conditions of test specimens 25.3 Rounding off the test results 25.4 Test report . 36 Static property tests . 36.1 Test for hardness of rubber core 36.2 Tensile strength test . 36.3 Fabric adhesion test . 46.4 Tension-cord adhesion test 56.5 Tooth-shear test . 66.6 Test for resi
8、stance to high temperature 86.7 Test for resistance to low temperature 96.8 Test for resistance to oil 96.9 Test for resistance to ozone . 96.10 Test for resistance to water 9Bibliography .10BS ISO 12046:2012ISO 12046:2012(E)ForewordISO (the International Organization for Standardization) is a world
9、wide federation of national standards bodies (ISO member bodies). The work 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 t
10、hat committee. International organizations, governmental and non-governmental, 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.International Standards are drafted in
11、accordance with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard re
12、quires approval by at least 75 % of the member bodies casting a vote.Attention is drawn to the possibility 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.ISO 12046 was prepared by Technic
13、al Committee ISO/TC 41, Pulleys and belts (including veebelts), Subcommittee SC 4, Synchronous belt drives.This second edition cancels and replaces the first edition (ISO 12046:1995), which has been technically revised.iv ISO 2012 All rights reservedBS ISO 12046:2012INTERNATIONAL STANDARD ISO 12046:
14、2012(E)Synchronous belt drives Automotive belts Determination of physical properties1 ScopeThis International Standard specifies test methods for determining the physical properties of synchronous belts used in driving engine parts, such as camshafts, fuel injection pumps, balancing shafts. These te
15、st methods are intended to provide a means of characterizing synchronous belt properties for belts which are evaluated and qualified by dynamic laboratory and field testing.NOTE The dimensional characteristics of these belts are the subject of ISO 9010.2 Normative referencesThe following referenced
16、documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 48, Rubber, vulcanized or thermoplastic Determination of hardness (hard
17、ness between 10 IRHD and 100 IRHD)ISO 1817, Rubber, vulcanized or thermoplastic Determination of the effect of liquidsISO 7619-1, Rubber, vulcanized or thermoplastic Determination of indentation hardness Part 1: Durometer method (Shore hardness)ISO 7619-2, Rubber, vulcanized or thermoplastic Determi
18、nation of indentation hardness Part 2: IRHD pocket meter method3 PrincipleEvaluation of the physical properties of automotive synchronous belts through standardized test methods. These test methods are independent of tooth profiles.4 Test methodsThe tests are listed in Table 1. ISO 2012 All rights r
19、eserved 1BS ISO 12046:2012ISO 12046:2012(E)Table 1 TestsTest Subclause No.Hardness of rubber coreTensile strengthFabric adhesionTension-cord adhesionTooth shearResistance to high temperatureResistance to low temperatureResistance to oilResistance to ozoneResistance to water6.16.26.36.46.56.66.76.86.
20、96.105 General conditions for testing5.1 Standard environmental conditionsStandard conditions in the laboratory shall be maintained at a temperature of (25 5) C, a relative humidity of (65 20) % and an atmospheric pressure of 86 kPa to 106 kPa . The test conditions should be recorded.5.2 Standard co
21、nditions of test specimensThe test specimens shall be tested at least 24 h after vulcanization and shall be kept for at least 1 h prior to test in a room maintained under standard conditions.5.3 Rounding off the test resultsThe results of each test shall be rounded off and shall be recorded accordin
22、g to the number of figures specified in Table 2.Table 2 Rounding off of resultsTest Unit Measured test value Test results to be obtainedHardness of rubber core Shore A or IRHD Integer IntegerTensile strength N Nearest 10 Nearest 100Fabric adhesion N Integer IntegerTension-cord adhesion N Nearest 10
23、Nearest 10Tooth shear N Nearest 10 Nearest 10EXAMPLES Nearest tens3 474 3 4703 475 3 480Nearest hundreds3 440 3 4003 450 3 5002 ISO 2012 All rights reservedBS ISO 12046:2012ISO 12046:2012(E)5.4 Test reportFor each test, the test report shall include the following information:a) number of teeth, pitc
24、h, tooth profile and width of specimen;b) constituent materials of specimen;c) production code of specimen;d) date of test;e) number of specimens;f) test temperature, relative humidity and atmospheric pressure;g) type of test apparatus.6 Static property tests6.1 Test for hardness of rubber core6.1.1
25、 Test specimensThe test specimen shall be either an endless belt or a cut belt with a minimum length of 100 mm.6.1.2 ProcedurePlace the specimen, with teeth pointing downward, on a flat surface and measure the flat portion of the belt above a tooth, using a Shore type A durometer as described in ISO
26、 7619-1, or an IRHD tester as described in ISO 48 or ISO 7619-2, or an equivalent apparatus.6.1.3 Expression of resultsRecord the average of five different measurements along the belt, rounded off as in the following examples.EXAMPLE 174 75 75 74 74574 474+=,EXAMPLE 275 75 75 74 74574 675+=,6.2 Tens
27、ile strength test6.2.1 Test specimensThe test specimen shall be either an endless belt or two cut belts with a minimum length of 250 mm each.6.2.2 ProcedureMount an endless-belt test specimen, with teeth pointing upward, on two flat pulleys having an equivalent diameter ranging between 100 mm and 17
28、5 mm and which are free to rotate. Apply a tension force to the specimen at the speed of (50 5) mm/min until belt separation occurs. ISO 2012 All rights reserved 3BS ISO 12046:2012ISO 12046:2012(E)If two cut belts are used as test specimens, the length gripped shall be at least 50 mm with a minimum
29、distance of 150 mm between the two grips. Apply a tension force to one specimen at the speed of (50 5) mm/min until separation takes place. Repeat the test with the second specimen.6.2.3 Expression of resultsThe value for the tensile strength shall be taken as half the measured value for the endless
30、-belt specimen or the smaller of the measured values of the two cut belts. Any data obtained when the specimen separates on the pulley surface or at the gripped portion shall be discarded.6.3 Fabric adhesion test6.3.1 Test specimensTwo specimens with a minimum length of 100 mm shall be cut from a be
31、lt.6.3.2 ProcedurePlace each specimen in the grips of a tensile-testing device, positioning the root line of the first tooth (No. 1) between 1 and 2, as illustrated in Figure 1.Key1 grip A of the tensile-testing device2 grip B of the tensile-testing device3 tooth body4 root line of first toothFigure
32、 1 Installation of the specimenApply a tension force to the specimen using the power-actuated grip. The grip should travel uniformly at (50 5) mm/min, causing the fabric to peel from the surface of the belt. Measure the adhesion force of three consecutive teeth.6.3.3 Expression of resultsThe test re
33、sults shall be summarized separately for adhesion at the tooth body and at the root line between teeth. Results are recorded in terms of force per millimetre width. The adhesion force at the tooth body is the lowest peak value of the two specimens, as illustrated in Figure 2. The adhesion force at t
34、he root line between teeth is the lowest value of the two specimens at the beginning of the first tooth (No. 1).4 ISO 2012 All rights reservedBS ISO 12046:2012ISO 12046:2012(E)Key1 tooth bottom2 tooth body peak3 fabric adhesion force4 teethFigure 2 Adhesion results for three consecutive teeth6.4 Ten
35、sion-cord adhesion test6.4.1 Test specimensTwo specimens with a minimum length of 100 mm shall be taken from a belt. These shall be partially cut at two positions located 30 mm (see 6.4.2) apart to extract two cords, as illustrated in Figure 3.Dimensions in millimetresKey1 cut in the two cords2 cut
36、in all but two cords3 cut length4 tension cordsFigure 3 Specimen for tension-cord adhesion test ISO 2012 All rights reserved 5BS ISO 12046:2012ISO 12046:2012(E)6.4.2 ProcedurePlace the test specimen in the grips of a tensile-testing device. Apply a tension force to the specimen at the speed of (50 5
37、) mm/min until the two cords are extracted. If the cords break before they are extracted, the cut length may be reduced to a value that allows complete extraction.Repeat the test using the second test specimen.6.4.3 Expression of resultsThe lower value obtained from the two specimens is taken as the
38、 tension-cord adhesion value for a 30 mm length. Any tests showing results of improper sample preparation should be repeated.6.5 Tooth-shear test6.5.1 Test specimensA specimen with a minimum length of 200 mm shall be cut from a belt.6.5.2 ApparatusThe apparatus for the tooth-shear test is illustrate
39、d in Figure 4.Key1 grip of tensile-testing device2 specimen3 tooth-shearing chip4 slide bearing5 setting boltFigure 4 Tooth-shearing apparatus and specimen6.5.3 Tooth-shearing chipThe basic dimensions of the tooth-shearing chip are shown in Figure 5 and Table 3. The total length of the chip should b
40、e dimensioned to fit securely in the holding apparatus illustrated in Figure 4.6 ISO 2012 All rights reservedBS ISO 12046:2012ISO 12046:2012(E)Table 3 Minimum clearance between tooth-shearing chip and belt toothDimensions in millimetresBelt type Trapezoidal CurvilinearCm0,5 0,5hm0 0,1Key1 test belt2
41、 first test tooth3 tooth-shearing chipFigure 5 Tooth-shearing chipThe actual chip shall be designed to fit the specific type of belt being tested. The dimensions should be the same as the space between two adjacent nominal belt teeth with a 0,02 mm tolerance band.In setting up the test, the tooth-sh
42、earing chip should mate with the belt profile so that the chip nests between two adjacent belt teeth and conforms to the contours of the belt teeth, as illustrated in Figure 6. ISO 2012 All rights reserved 7BS ISO 12046:2012ISO 12046:2012(E)Key1 test belt2 first test tooth3 tooth-shearing chip4 seco
43、nd test tooth5 second cut line6 first cut lineFigure 6 Tooth preparation for shear testing6.5.4 ProcedurePlace the specimen in the tooth-shearing apparatus mounted on a tensile-testing device and tighten it with a setting force, in newtons, equal to 157 times the belt width in millimetres. Apply a t
44、ension force to the specimen at the speed of (50 5) mm/min until tooth-shearing rupture occurs. During the test, the next tooth shall be cut off as illustrated in Figure 6 and, as a rule, three teeth shall be tested. Any specimen which has a splice in the fabric shall be excluded from the test.NOTE
45、The setting force of the specimen is provided by the setting bolt. Accordingly, the relationship between the setting force and the setting torque is determined by calibration.6.5.5 Expression of resultsRecord, in terms of force per millimetre width, the minimum value of the observed data.6.6 Test fo
46、r resistance to high temperature6.6.1 Test specimensThe specimen shall be a cut belt with a minimum length of 100 mm.6.6.2 ProcedureAge the specimen in an air-circulating oven, or similar, for 70 h at (125 2) C or 70 h at (150 2) C for heat-resistant belts. After ageing, allow the specimen to cool u
47、nder standard conditions (see 5.1) for at least 1 h prior to carrying out the following tests:a) hardness of rubber core (see 6.1);b) fabric adhesion (see 6.3).8 ISO 2012 All rights reservedBS ISO 12046:2012ISO 12046:2012(E)6.7 Test for resistance to low temperature6.7.1 Test specimensThe specimen s
48、hall be a cut belt with a minimum length of 150 mm.6.7.2 ProcedurePlace the test specimen in a cold chamber for a minimum of 5 h at (-40 2) C. In this cold chamber, bend the specimen, with the teeth on the inside, around a mandrel measuring 25 mm in diameter and inspect the specimen for cracks or ot
49、her visible defects. The mandrel shall be kept in the cold chamber at the same time.6.8 Test for resistance to oil6.8.1 Test specimensThe specimen shall be a cut belt with a minimum length of 200 mm.6.8.2 ProcedureImmerse the test specimen in oil No. 1 of ISO 1817, or equivalent, for 70 h at (100 2) C. Then remove the specimen from the oil, allow it to cool under standard conditions (see 5.1) for at least 1 h prior to carrying out the following tests:a) ha
