1、 ISO 2014 Petroleum and related products Determination of shear stability of lubricating oils containing polymers Method using a tapered roller bearing Ptrole et produits connexes Dtermination de la stabilit au cisaillement des huiles lubrifiantes contenant des polymres Mthode avec roulement rouleau
2、x coniques INTERNATIONAL STANDARD ISO 26422 Second edition 2014-12-15 Reference number ISO 26422:2014(E) ISO 26422:2014(E)ii ISO 2014 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2014 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized o
3、therwise 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 ISOs member body in the country of the requester. ISO copyright off
4、ice Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ISO 26422:2014(E)Contents Page Foreword iv 1 Scope . 1 2 Normative references 1 3 T erms and definitions . 1 4 Principle 2 5 Reagents and materials . 2
5、6 Apparatus . 2 7 Preparation 3 7.1 Preparing the tapered roller bearing and testing apparatus assembly . 3 7.2 Assembly of the shear stability apparatus 4 7.3 Running-in of the tapered roller bearing . 4 7.4 Test conditions 5 7.5 Validation of test bearings 6 8 Procedure. 6 9 Referencing 6 9.1 Gene
6、ral . 6 9.2 Validation of new test bearings 6 9.3 Referencing in service . 6 9.4 Frequency of reference testing 7 9.5 Reference fluid control limits . 8 9.6 Reference fluids 8 10 Reporting of results . 8 11 Precision . 8 12 Test report . 9 Bibliography .10 ISO 2014 All rights reserved iii ISO 26422:
7、2014(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 is normally carried out through ISO technical committees. Each member body interested in a subject for w
8、hich 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 part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all
9、 matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. Th
10、is 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 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 o
11、r 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 patent declarations received (see www.iso.org/patents). Any trade name used in this document is information given for the convenience of user
12、s and does not constitute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementa
13、ry information The committee responsible for this document is ISO/TC 28, Petroleum products and lubricants. This second edition cancels and replaces the first edition (ISO 26422:2011), which has been technically revised. The objective of the revision is to harmonize the test methodology of ISO 26422
14、 with that of CEC L-45-99 regarding reference fluids, referencing procedure, and the precision statement, thereby avoiding differences between two test methods which are technically equivalent. ISO 26422 is based upon DIN 51350-6, 1which has also been adopted by the Co-ordinating European Council (C
15、EC) as CEC-L-45-99. ISO/TC 28 acknowledges permission granted by Coordinating European Council to reproduce selected parts of CEC Test Method L-45-99 2to assist with the preparation of this International Standard.iv ISO 2014 All rights reserved Petroleum and related products Determination of shear s
16、tability of lubricating oils containing polymers Method using a tapered roller bearing WARNING The use of this International Standard can involve hazardous materials, operations, and equipment. This International Standard does not purport to address all of the safety problems associated with its use
17、. It is the responsibility of the user of this International Standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. 1 Scope This International Standard specifies a method of determining the shear stability of polymer-c
18、ontaining lubricating oils by the four-ball machine as specified in ISO 20623, but using a tapered roller bearing. The test results allow prediction of the in-service permanent viscosity loss. NOTE Other International Standards exist which evaluate viscosity loss of polymer-containing oils. The meth
19、od specified within this International Standard subjects fluids to a higher shear rate than, for example, the diesel injector nozzle shear test described within ISO 20844. 3It is particularly appropriate for lubricants being used in high shear applications, such as components with gears and roller b
20、earings. In such applications, the shear rate in the ISO 20844 test method can be too low to generate a realistic permanent loss in viscosity of the fluid. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its a
21、pplication. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 3104, Petroleum products Transparent and opaque liquids Determination of kinematic viscosity and calculation of dynamic visc
22、osity ISO 3105, Glass capillary kinematic viscometers Specifications and operating instructions ISO 20623, Petroleum and related products Determination of the extreme-pressure and anti-wear properties of fluids Four ball method (European conditions) 3 T erms a nd definiti ons For the purposes of thi
23、s document, the following terms and definitions apply. 3.1 percentage viscosity loss R V measure of shear stability calculated in accordance with the following equation: R where INTERNATIONAL ST ANDARD ISO 26422:2014(E) ISO 2014 All rights reserved 1 ISO 26422:2014(E) 0 is the kinematic viscosity at
24、 100 C of the fluid before shear, expressed in mm 2 s 1 ; 1 is the kinematic viscosity at 100 C of the fluid after shear, expressed in mm 2 s 1 . Note 1 to entry: A small value indicates a high resistance to viscosity shear loss. Note 2 to entry: The tapered roller bearing test is also referred to a
25、s the KRL (Kegelrollenlager) principle. 4 Principle Using the splash lubrication method, a volume of 40 ml of the lubricating fluid is tested at a constant temperature of 60 C in a tapered roller bearing driven in the four-ball machine. The test is performed at constant speed and the load applied du
26、ring a given running time is 5 000 N. The kinematic viscosity of the lubricating fluid is determined at a temperature of 100 C before and after the test. The percentage viscosity loss, R V , is calculated from these two viscosity measurements. NOTE Some classification systems specify that the kinema
27、tic viscosity before and after shear is determined at temperatures other than 100 C, e.g. at 40 C. 5 Reagents and materials 5.1 Cleaning solvents, appropriate to the last fluid type tested. For fluids based upon petroleum mineral oil, aliphatic hydrocarbons, and acetone are usually suitable. For som
28、e hydraulic fluids, a low molecular mass alcohol can assist in the initial stages of cleaning. 6 Apparatus 6.1 Four-ball machine, as specified in ISO 20623. 6.2 Tapered roller bearing, type SKF 32008 X/Q, which incorporates optimised contact geometry and surface finish. The single row tapered roller
29、 bearing consists of an inner ring with cage and roller assembly and an outer ring. It is advisable that the inner and outer rings be considered to be a matched pair when obtained from the supplier and these components should not be interchanged with those of other sets of bearings. Precision has be
30、en established using the 32008 X/Q test bearing manufactured by SKF. It is strongly recommended that only bearings of this specification manufactured by SKF are used. The use of ISO 355 dimension series 3CD bearings of alternative specification and manufacturer requires validation by inter-laborator
31、y exercises to establish technical suitability, test precision, and service life. 6.3 Shear stability testing apparatus 1) , as shown in Figure 1. This is available from several manufacturers. It is recommended that only apparatus which has been proven in tests run in accordance with CEC L-45-99 2or
32、 DIN 51350-6 1is used. 6.4 Temperature control device, for controlling the temperature of the fluid to a temperature of 60 C 1 C. This typically comprises of an electrical heating band clamped around the housing, galleries within the housing through which cooling water can be passed, a temperature s
33、ensor and a control system to automatically energize and de-energize the heating, and cooling circuits as required. 1) Information on suitable products available commercially can be obtained from DIN-Bezugsquellen fr normgerechte Erzeugnisse im DIN Deutsches Institut fr Normung e.V., Burggrafenstrae
34、 6, D-10787 Berlin, Germany. This information is given for the convenience of users of this International Standard and does not constitute an endorsement by ISO of these products.2 ISO 2014 All rights reserved ISO 26422:2014(E) 6.5 Viscometer, an appropriate glass capillary viscometer meeting the re
35、quirements of ISO 3105 or a suitable automatic viscometer should be used for the determination of kinematic viscosity in accordance with ISO 3104. Key 1 torque reaction arm 8 housing cover 2 test fluid chamber 9 tapered roller bearing outer ring 3 O-ring 10 cooling galleries for temperature control
36、4 O-ring 11 coolant inlet 5 tapered roller bearing inner ring with cage and rollers 12 housing 6 drive spindle 13 conical mounting point 7 drive assembly for tapered roller bearing inner ring assembly 14 location of temperature sensor Figure 1 Shear stability testing apparatus 7 Preparation NOTE The
37、 numbers in parentheses in this clause correspond to the items detailed in Figure 1. 7.1 Preparing the tapered roller bearing and testing apparatus assembly 7.1.1 Prior to the test, clean the housing, housing cover, and the tapered roller bearing assembly with a cleaning solvent, e.g. n-heptane, and
38、 dry in a stream of dry air or with a clean, dry, lint-free cloth. 7.1.2 Inspect the O-rings fitted to the housing and housing cover (3) and (4) and ensure that they are properly located and free from damage. 7.1.3 The outer ring and inner ring with cage and roller assembly of the test bearing shoul
39、d be carefully inspected for evidence of mechanical damage, surface deposits, corrosion, and thermal staining. Normal wear of the outer ring and rollers is indicated by a matt grey surface with light circumferential scratching. ISO 2014 All rights reserved 3 ISO 26422:2014(E) If damage due to pittin
40、g, scoring, or surface staining is observed, the outer ring and inner ring with cage and rollers should be replaced as an assembly. If surface deposits cannot be removed by the cleaning procedure detailed in 7.1.1, the test bearing assembly should be discarded and replaced. 7.2 Assembly of the shear
41、 stability apparatus NOTE The numbers in parentheses in this clause correspond to the items detailed in Figure 1. 7.2.1 Fit the test bearing outer ring (9) into the cleaned housing (12) and fill with 40,0 ml 0,5 ml of the test fluid. 7.2.2 Press the cleaned inner ring with cage and roller assembly (
42、5) onto the drive assembly (7) and check to ensure that it is seated correctly. 7.2.3 Place the inner ring with cage and roller assembly and drive assembly into the prepared housing ensuring that the rollers are fully seated in the outer ring. Screw the housing cover into position and fully tighten
43、it using hand pressure only. 7.2.4 Locate the assembled testing apparatus into the four-ball machine ensuring that the drive spindle (6) engages with the drive assembly for the inner ring with cage and roller assembly (7). Apply a load of 5 000 N 200 N. 7.2.5 Connect the temperature sensor (located
44、at position 14) to the temperature control unit and check their correct function. 7.3 Running-in of the tapered roller bearing Before starting the test, ensure that the SKF 32008 X/Q test bearing has been run-in in accordance with the running-in procedure detailed in Figure 2.4 ISO 2014 All rights r
45、eserved ISO 26422:2014(E) F i g u r e 2 R u n n i n g - i n p r o c e d u r e f l o w c h a r t : V a l i d a t i o n f o r n e w t e s t b e a r i n g s 7.4 Test conditions The test conditions are specified in Table 1. Table 1 Test conditions Test parameter Test condition Drive motor speed 1 475 mi
46、n 1 25 min 1 Lubricant temperature 60 C 1 C Lubricant quantity 40,0 ml 0,5 ml Test load 5 000 N 200 N Test duration 1 740 000 500 motor revolutions, equivalent to approximately 20 h Test runs of shorter or greater duration than 1 740 000 revolutions (approximately 20 h) might be more appropriate for
47、 certain applications. For example, longer duration tests of 200 h have shown good correlation with some high severity applications conditions as found in manual transmissions or axles, whereas shorter duration tests of 4 h or 8 h might be of appropriate severity for high viscosity index hydraulic f
48、luids and shock absorber fluids. The precision of tests conducted for durations other than 1 740 000 revolutions has not been established. ISO 2014 All rights reserved 5 ISO 26422:2014(E) 7.5 Validation of test bearings Flowcharts detailing the processes for running-in and validation of new test bea
49、rings and validation of test bearings in service are given in Figure 2 and Figure 3, respectively. 8 Procedure 8.1 After performing the check on the function of the thermal sensor and controller as described in 7.2.5, and before starting the drive motor, switch on the heater control unit and pre-heat the test oil to 50 C 1 C. 8.2 Once the temperature has achieved 50 C 1 C, set the heater control unit to a test fluid temperature of 60 C 1
