1、BSI Standards PublicationBS ISO 12900:2015Hard coal Determination ofabrasivenessBS ISO 12900:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 12900:2015. It supersedes BS 1016-111:1998 which is withdrawn.The UK participation in its preparation was entrusted
2、 to Technical Committee PTI/16, Solid mineral fuels.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The Britis
3、h Standards Institution 2015. Published by BSI Standards Limited 2015ISBN 978 0 580 88407 8ICS 73.040Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 June 2015
4、.Amendments/corrigenda issued since publicationDate Text affected ISO 2015Hard coal Determination of abrasivenessHouille Dtermination de labrasivitINTERNATIONAL STANDARDISO 12900Second edition 2015-06-01Reference number ISO 12900:2015(E)BS ISO 12900:2015ISO 12900:2015(E)ii ISO 2015 All rights reserv
5、edCOPYRIGHT PROTECTED DOCUMENT ISO 2015, Published in SwitzerlandAll rights reserved. Unless otherwise specified, 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 intran
6、et, 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 officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.is
7、o.orgBS ISO 12900:2015ISO 12900:2015(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Principle 14 Apparatus . 15 Sample preparation . 46 Procedure. 77 Calculation 78 Reporting of results . 79 Precision of the determination . 710 Test report . 8Bibliography 9 ISO 2015 All rights reser
8、ved iiiContents PageBS ISO 12900:2015ISO 12900:2015(E)ForewordISO (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. E
9、ach 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 part in the work. ISO collaborates closely with the Internati
10、onal Electrotechnical Commission (IEC) on all 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 differen
11、t types of ISO documents should be noted. This 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 no
12、t be held responsible for identifying any or 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 inf
13、ormation given for the convenience of users 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
14、the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 27, Solid mineral fuels, Subcommittee SC 5, Methods of analysis.This second edition cancels and replaces the first edition (ISO 12900:1997), of which it constitutes a minor revision.iv ISO 20
15、15 All rights reservedBS ISO 12900:2015ISO 12900:2015(E)IntroductionThe abrasiveness of coal is recognized as a factor in coal operations, from mining to utilization, requiring a standard method of measurement and evaluation, as some coals are more abrasive than others.The interaction between coal a
16、nd conveying, storage, and crushing equipment results in component wear. In particular, higher contact pressures in some coal pulverizers result in significant wear.For the ranking or relative comparison of the abrasiveness of coals, a test was developed1which standardized the following equipment va
17、riables:a) test equipment dimensions and tolerances;b) speed of rotation of wearing components;c) properties of the wearing components;d) mass of the test portion;e) top particle size of the test portion;f) duration of the test.The abrasiveness of coal is generally a function of two factors: the phy
18、sical properties of the coal, in particular, moisture content, mineral content, and mineral characteristics;12 3 4 5 6the mechanics of the operations to which the coal is subjected.NOTE Moisture contents over 10 % in the test sample after air-drying and laboratory equilibration might give anomalous
19、results; the reason for this has not been established.Wear on coal-pulverizing elements in industrial mills is influenced by the physical characteristics of the coal and its mineral constituents, the mechanical characteristics of the mill, including the milling pressures, alloy material properties a
20、nd coal feed flow, and the operation of the mill. Abrasiveness as determined by this International Standard has been demonstrated to provide initial empirical estimates of specific wear rates in certain types of industrial tube-ball mills, vertical spindle mills, and high-speed hammer mills,3 6with
21、different coefficients for each mill type.Abrasiveness as determined by this International Standard might be of value in providing an initial estimate of the likely wear in other applications, giving the relative effect of different coals. ISO 2015 All rights reserved vBS ISO 12900:2015BS ISO 12900:
22、2015Hard coal Determination of abrasiveness1 ScopeThis International Standard describes a method for determining the abrasiveness of hard coal.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. Fo
23、r dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 589, Hard coal Determination of total moistureISO 3310-1, Test sieves Technical requirements and testing Part 1: Test sieves of metal wire
24、clothISO 6507-1, Metallic materials Vickers hardness test Part 1: Test methodISO 13909-2, Hard coal and coke Mechanical sampling Part 2: Coal Sampling from moving streamsISO 13909-3, Hard coal and coke Mechanical sampling Part 3: Coal Sampling from stationary lotsISO 13909-4, Hard coal and coke Mech
25、anical sampling Part 4: Coal Preparation of test samplesISO 18283, Hard coal and coke Manual sampling3 PrincipleFour standard steel blades are rotated under specified conditions in a 2 kg mass of prepared coal in a test machine. The abrasiveness is calculated from the mass of steel lost during the t
26、est.4 Apparatus4.1 Abrasion test machine, comprising the following components:4.1.1 Blades, of the following types:a) A set of four reference blades1), having a Vickers hardness of 160 15 when tested in accordance with ISO 6507-1. When new, the blades, machined with the bar rolling direction paralle
27、l to the line of the bolt holes, from a bar of carbon steel, shall have the shape, dimensions, and surface finish shown in Figure 1. To reduce the extent of varying hardness near the surface, care should be taken during machining to minimize surface distortion and heating of the blades. The blades s
28、hall be marked for identification.A new set of blades shall be “run in” by carrying out a number of abrasiveness determinations on 2 kg test portions of the same coal until constant results (within the limits of repeatability, see Clause 9) are obtained.When blades are not in use, they should be wra
29、pped in a cloth containing a rust-preventive solution and stored in a desiccator. Immediately prior to use, the blades should be cleaned with a suitable solvent, e.g. methylated spirits, and allowed to air-dry in a desiccator.1) Suitable blades are available from Mitsui Babcock Energy Ltd., Technolo
30、gy Centre, Renfrew, U.K.INTERNATIONAL STANDARD ISO 12900:2015(E) ISO 2015 All rights reserved 1BS ISO 12900:2015ISO 12900:2015(E)The reference set of blades shall be discarded when any of the following conditions occurs: the wear on the leading edge or corners is greater than 3 mm; the blades cannot
31、 be correctly adjusted in the jig.After a number of tests, the wearing surface of the blades might become rough, in which case each blade should be gently polished with a finegrained emery paper and reconditioned prior to further use.Dimensions in millimetresFigure 1 Bladesb) A set of four working b
32、lades, conforming to the requirements of 4.1.1 and checked successively against the reference blades when their original mass has decreased by 2 %, 3 %, 4 %, or more frequently if required.The working set of blades shall be discarded when the results obtained on a sample using the working set differ
33、, after a minimum of three determinations, by more than the limit of repeatability from the value obtained using the reference set.After a number of tests, the wearing surface of the blades might become rough, in which case each blade should be gently polished with a finegrained emery paper and reco
34、nditioned prior to further use.4.1.2 Mill mortar, having dimensions as shown in Figure 2 and fitted with a dust-tight cover. The lower sections of the walls may be recessed to accommodate a replaceable liner. Hardened metal or hard metal plate is recommended for the mill mortar (or liner if fitted).
35、 The mill mortar shall be discarded (or a new liner fitted) when the tolerance shown in Figure 2 is exceeded.2 ISO 2015 All rights reservedBS ISO 12900:2015ISO 12900:2015(E)4.1.3 Quadrant, having four arms with elongated bolt holes for attachment and adjustment of the blades using round-head bolts,
36、nuts, and spring washers. The quadrant shall be capable of being removed from the mill mortar (see Figure 2).Some test machines have quadrants which are not removable. For these machines, the blades should be adjusted using suitable gauges so that the trailing and bottom edges are positioned (6,4 0,
37、1) mm from the wall and bottom of the mill mortar.4.1.4 Drive, for driving the quadrant at 24,5 s1 0,5 s1either directly or indirectly by a constant-speed electric motor. The shaft shall be fitted with a revolution counter and automatic cut-off switch.NOTE A 2,5 kW motor is suitable. The drive can b
38、e above or below the mill mortar.Dimensions in millimetres219,25218,75203,25202,756,56,36,56,3aBBA-AAAB-BKeya Direction of rotation.Figure 2 Mill mortar and quadrant assembly4.1.5 Jig, metal, (see Figure 3) to assist in attaching and adjusting the blades to the quadrant arms. The jig dimensions shal
39、l be such that, when the blades are secured on the quadrant arms so that they are touching the walls and bottom of the jig, they will have the correct clearances when the quadrant is replaced in the mill mortar. The clearance (6,3 mm to 6,5 mm) between the blades and the mill mortar shall be checked
40、 periodically using a limit gauge. ISO 2015 All rights reserved 3BS ISO 12900:2015ISO 12900:2015(E)4.2 Balance, capable of weighing a mass of not less than 2 kg to within 1 g or better.4.3 Balance, capable of weighing the blades to within 0,1 mg.4.4 Jaw crusher, capable of reducing coal particles to
41、 less than 6,7 mm with minimum production of fines.4.5 Test sieves, having apertures 6,7 mm, 16 mm, and 31,5 mm and conforming to the requirements of ISO 3310-1.4.6 Fine brass brush, for cleaning blades.5 Sample preparationThe test sample shall be of 6,7 mm nominal top size and shall have a fines co
42、ntent of not more than 30 % less than 1 mm.The sample shall be taken in accordance with ISO 18283, ISO 13909-2, or ISO 13909-3 and be prepared in accordance with ISO 13909-4.A suitable procedure, as shown in the flow diagram in Figure 4, is as follows.The sample is prepared to give 55 kg or more of
43、material having a nominal top size of 31,5 mm. It is then air-dried.The air-dried sample is sieved using a 16 mm sieve. The fraction passing this sieve is set aside and the retained material is crushed (in one or more steps) to pass a 16 mm sieve.If required, the sample of coal less than 16 mm may b
44、e divided, but to no less than 20 kg.The sample is then sieved using a 6,7 mm sieve. The fraction passing this sieve is set aside and the retained material is crushed (in one or more steps) to pass a 6,7 mm sieve.All the minus 6,7 mm coal is collected together and thoroughly mixed.4 ISO 2015 All rig
45、hts reservedBS ISO 12900:2015ISO 12900:2015(E)Dimensions in millimetres190,25189,7538,137,9a123A-AAAKey1 quadrant arm2 retaining bolt3 blades with curved edgesa Direction of rotation.Figure 3 Jig and location of blades ISO 2015 All rights reserved 5BS ISO 12900:2015ISO 12900:2015(E)Sample 20210 % of
46、 meanSee NoteSee NoteNOTE As the test result is a function of the air-dried moisture in the test portion (among other factors), a value for reproducibility cannot be quoted. A series of international interlaboratory tests have failed to generate highly reproducible results for this test.10 Test repo
47、rtThe test report shall contain the following information:a) identification of the sample;b) a reference to this International Standard and its year of publication, i.e. ISO 12900:2015;c) date of the test;d) the test result;e) the moisture content of the sample after air-drying and laboratory equili
48、bration;f) any unusual features noted during the determination;g) any operation not included in this International Standard or regarded as optional.8 ISO 2015 All rights reservedBS ISO 12900:2015ISO 12900:2015(E)Bibliography1 Yancey H.F., Geer M.R., Price J.D. Trans AIME. Min. Eng. 1951 March2 Du To
49、it P., & Bonapace A.C. Determination of the Abrasiveness of Coal with the Apparatus of Yancey, Geer and Price. Coal, Gold and Base Minerals of Southern Africa. 1973, 21 pp. 36423 Sligar N.J. The abrasiveness of coal, NERDDC Report No. 652, Dept Primary Industries & Energy, Canberra, Australia, June 19864 Spero C. Assessment and prediction of coal abrasiveness. Fuel. 1990, 69 pp. 116811765 Spero C. Review of test methods for abrasive wear in ore grinding. Wear. 1991, 1
