1、BRITISH STANDARD BS ISO 12987:2004 Carbonaceous materials for the production of aluminium Anodes, cathodes blocks, sidewall blocks and baked ramming pastes Determination of the thermal conductivity using a comparative method ICS 71.100.10 BS ISO 12987:2004 This British Standard was published under t
2、he authority of the Standards Policy and Strategy Committee on 30 March 2005 BSI 30 March 2005 ISBN 0 580 45701 X National foreword This British Standard reproduces verbatim ISO 12987:2004 and implements it as the UK national standard. The UK participation in its preparation was entrusted to Technic
3、al Committee CII/24, Raw materials for the aluminium industry, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications referred to in this doc
4、ument may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract
5、. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for c
6、hange, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii to v, a blank page, pages 1 to 6, an inside back cover and a b
7、ack cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsINTERNATIONAL STANDARD ISO 12987 First edition 2004-07-01 Reference number ISO 12987:2004(E) OSI 2004 Carbonaceous materials for the p
8、roduction of aluminium Anodes, cathodes blocks, sidewall blocks and baked ramming pastes Determination of the thermal conductivity using a comparative method Produits carbons utiliss pour la production de laluminium Anodes, cathodes blocs, blocs de faade et ptes de brasquage cuites Dtermination de l
9、a conductivit thermique temprature ambiante par une mthode comparativeBSISO12987:2004ISO :78921(4002)E ii ISO 4002 All rithgs reresvde id FDPscalimer ThFDP si fam eliy ctnome niat deddebyepfa.sec In cacnadrociw eth sebodA sneciliycilop gn, thf siam elirp eb ytnide or viewb detu llahs ton tide ebed l
10、nuet sst ehyfepcaa hcihw serdebme et desnecil era dedo tsni dnat no dellahpmoc eturep reformign ttide ehign. In odt gnidaolnwhsi liferap ,ticca setpe trehnie snopser ehtibtiliy fo not fnirA gnigniycilop gnisnecil sebod. Teh SItneC Olar Seerctraiat catpecs ibail ontily t nih.aera si Aebod t a sirrame
11、dak fo AsyS ebodtmeI snocrropta.de teDalis fo tfos ehtwcudorp erats t desuo taerct ehsi FDP fb nac elie ft ni dnuoG ehreneI lanfo relative to tf eh;eli tP ehDF-rctaenoi temaraptpo erew sremizif deorp rinti.gn Evrey t neeb sah eracakt neo rusnee ttah tf ehtius si elibaf elosu re by ISO memdob rebsei.
12、 In eht kilnuyle evtne ttah a borplem retalit gno it si f,dnuo esaelp inform thtneC eral ceSrteraiat ta teh sserdda vigoleb new. IOS 4002 Alr lithgs reresv.de sselnU toesiwreh sficep,dei rap ont fo thbup silitaciam nocudorper eb yde or tuilidez na nif yorm ro by nam ysnae, tcelerm ro cinoecinahcal,
13、tohp gnidulcnicopom dna gniyicrfomli, tiwuoht repsimsi noin wrtif gnirtie mohI reSO ta the asserdd ebwol or ISOmem sreb obyd t nitnuoc ehry fo teh euqertsre. SIc Oopyright ofifce saCe soptael 65 -HCG 1121eneva 02 Te.l 22 14 + 10 947 11 Fax + 22 14 0 9479 74 Eam-il ocpyrithgios.ogr Web wwwi.soo.rg Pu
14、bni dehsil Stiwrezldna BSISO12987:2004ISO 89214002:7)E( ISO 4002 r llAithgs reservde iii Contents Page 1 Scope 1 2 Terms and definitions 1 3 Reagents and materials 2 4 Apparatus . 2 5 Sampling . 2 6 Procedure . 4 7 Calculation . 4 8 Precision . 4 9 Test report 5 Bibliography . 6 BSISO12987:2004ISO :
15、78921(4002)E iv ISO 4002 All rithgs reresvde 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 memb
16、er 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 International Ele
17、ctrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in 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 adop
18、ted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires 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 pate
19、nt rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 12987 was prepared by Technical Committee ISO/TC 47, Chemistry, Subcommittee SC 7, Aluminium oxide, cryolite, aluminium fluoride, sodium fluoride, carbonaceous products for the aluminium industry. BSISO12
20、987:2004ISO 89214002:7)E( ISO 4002 r llAithgs reservde v Introduction Knowledge of the thermal conductivity of carbonaceous materials allows calculations of the heat transfer and losses in electrolysis cells. BSISO12987:2004blank 4002:78921OSISBANRETNIITOTS LANDNADRA ISO 89214002:7)E( ISO 4002 r llA
21、ithgs reservde 1 Carbonaceous materials for the production of aluminium Anodes, cathodes blocks, sidewall blocks and baked ramming pastes Determination of the thermal conductivity using a comparative method 1S c o p e This International Standard specifies a method for the determination of thermal co
22、nductivity of carbonaceous material in the temperature range of to . The typical range of thermal conductivity for these materials is to . This method can be used for other carbon materials, such as graphitized electrodes for other applications. 2 Terms and definitions For the purposes of this docum
23、ent, the following terms and definitions apply. 2.1 thermal conductivity material property, expressed in , obtained by determining the heat flow at a given temperature difference through a body with height and cross-sectional area as follows: (1) where is the heat flow, expressed in watts; is the te
24、mperature difference, expressed in kelvins; is the height, expressed in metres, of the body; is the cross-sectional area, expressed in square metres NOTE 1 For cylindrical test specimens: (2) where is the diameter of the test specimens, expressed in metres NOTE 2 This temperature difference is compa
25、red to those obtained with reference specimens thereby allowing the determination of the thermal conductivity of the test specimen. 20 C6 0 C 2 W/(Km) 100 W/(Km) W/(Km) dQ dt hA = dQ dt 1 h A dQ dt h A A = d 2 4 d BSISO12987:2004ISO :78921(4002)E 2 ISO 4002 All rithgs reresvde 3 Reagents and materia
26、ls 3.1 Contact agent, for testing, consisting of Vaseline, glycerol or contact paste capable of improving the contact between the heads and the specimen. 3.2 Calibration specimens, which have been calibrated by a recognized calibration authority such as the producer of the equipment or a national st
27、andards body. Table 1 shows examples of reference materials for specimens to be calibrated by the producer of equipment or by national standards bodies. The thermal conductivity of these materials varies almost linearly with temperature over the range of to . 4 Apparatus 4.1 Typical measuring device
28、, schematically shown in Figure 1 and consisting of the following: 4.1.1 Lower head, as heat sink cooled to . 4.1.2 Thermostatically controlled device, capable of maintaining the water temperature at and a circulating rate of approximately . 4.1.3 Differential thermocouple. 4.1.4 Suitable voltmeter.
29、 4.1.5 Upper head, as heat source, heated to at least , preferentially , and accurate to . 4.1.6 Liquid thermostat, capable of maintaining the water temperature at , and a circulating rate of approximately , or electrical heating device maintaining the temperature of the upper head at . 4.1.7 Clampi
30、ng device, applying a minimum pressure of about and a cardanic suspension. 4.1.8 Insulating cylinder, to avoid heat loss. 4.2 Device for measuring dimensions, with error limit of , for example a vernier calliper as specified in ISO 6906 or a micrometer calliper as specified in ISO 3611. 4.3 Straight
31、 edge. 5 Sampling Select test specimens in accordance with a suitable sampling scheme, for example using ISO 8007-1 or ISO 8007-2. Table 1 Examples of reference materials Material Thermal conductivityat Flint glass 1,4 High alloy steel 14 Bronze 65 Brass 110 Aluminium pure 235 20 C 100 C W/(Km) 20 C
32、 99,9 % 20 C 0,1 C 20 C 0,02 C 10 l/min 40 C6 0 C 0,1 C 40 C 0,02 C 10 l/min 60 C 0,1 C 5 MPa 1% BSISO12987:2004ISO 89214002:7)E( ISO 4002 r llAithgs reservde 3 The diameter of the cylindrical test specimens shall be between and , the height shall be fromto and the end surfaces shall be plane. The a
33、ccuracy of the method is affected by the geometry of the test specimens. For high thermal conductivity materials, thinner and/or longer test specimens yield better results. For test specimens of height, the diameters in Table 2 have been found appropriate. The flatness of the end planes shall be bet
34、ter than , which can be checked by means of the straight edge (4.3). The test specimens shall be dried to constant mass. Key 1 lower head 2 water flowing through the lower head at and 3 differential thermocouple element 4 differential thermocouple element 5 insulating cylinder 6 test specimen 7 diff
35、erential thermocouple element 8 direction of heat flow 9 upper head 10 clamping pressure 11 heating element Figure 1 A typical device to perform the test shown schematically Table 2 Dimensions of test specimens Typical range of thermal conductivity Test specimen material Diameter a mm Up to 10 Anode
36、s 50 Baked ramming paste 5 to 120 Cathodes 50 or 30 80 to 120 Graphite electrodes 20 to 30 a Height of test specimens . The larger diameters are chosen for anodes, baked ramming paste and cathodes due to their coarser grain structure. 20 C 0,1 C 10 l/min T 2 T 1 T 0 (p)=200 N 20 mm 50 mm 5mm 50mm 20
37、 mm 0,05 mm W/(Km) = 20 mm BSISO12987:2004ISO :78921(4002)E 4 ISO 4002 All rithgs reresvde 6 Procedure 6.1 Measurement of test specimen dimensions Measure the height ( ) and diameter ( ) of the test specimens. 6.2 Calibration Close the upper (4.1.5) and lower (4.1.1) heads. Heat the apparatus to the
38、 operating temperature. When the temperatures of both heads are stable within , choose one or several calibration specimens with the same cross-section as the test specimens. A thin layer of contact agent (3.1) may be applied to both sample end faces. Separate the heads and centre the specimens betw
39、een the heads, close the heads on the specimen and apply and maintain a suitable pressure. When the reading of the differential thermocouple (4.1.3) is constant, record the thermoelectric voltage (4.1.4). The calibration curve (thermoelectric voltage as a function of ) can be determined from measure
40、ments of different calibration specimens with known thermal conductivity and dimensions (see DIN 51908). The thermoelectric voltage yields the quantity for any specimen. If an insulating cylinder is used for the measurement of the test specimens, this cylinder should be used for calibration, as well
41、. 6.3 Measurement of test specimens Test specimens with the same cross-sections as the calibration specimens are measured according to the measuring procedure given for calibration specimens in 6.2. 7 Calculation The thermal conductivity , expressed in , is calculated according to Equation (3) as fo
42、llows: (3) where is thermal conductivity, expressed in ; is taken from the calibration curve; is the height, expressed in metres, of the test specimen; is cross-sectional area, expressed in square metres, of the test specimen. 8P r e c i s i o n As specified in ASTM E691, the precision of this metho
43、d is as follows. a) The repeatability in is calculated by the following equation: b) The reproducibility in is calculated by the following equation: hd 0,1 C U A/h U dQ/dt 1/ W/(Km) = dQ dt 1 h A W/(Km) dQ dt 1 h A r W/(mK) r= 0,083 0,72 R W/(mK) R= 0,124+ 1,097 BSISO12987:2004ISO 89214002:7)E( ISO
44、4002 r llAithgs reservde 5 9 Test report The test report shall include the following information: a) all details necessary for the complete identification of the sample; b) a reference to this International Standard (ISO 12987:2004); c) the measuring temperatures; d) the results and the method used;
45、 e) details of any unusual features noted during the determination; f) details of any operation not included in this International Standard or in the International Standards to which reference is made, as well as any operation regarded as optional. BSISO12987:2004ISO :78921(4002)E 6 ISO 4002 All rit
46、hgs reresvde Bibliography 1 ISO 3611, Micrometer callipers for external measurement 2 ISO 5725-2:1994, Accuracy (trueness and precision) of measurement methods and results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method 3 ISO 6906, Ver
47、nier callipers reading to 0,02 mm 4 ISO 8007-1, Carbonaceous materials used in the production of aluminium Sampling plans and sampling from individual units Part 1: Cathode blocks 5 ISO 8007-2, Carbonaceous materials used in the production of aluminium Sampling plans and sampling from individual uni
48、ts Part 2: Prebaked anodes 6 ASTM E691, Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method 7 DIN 51908, Testing of carbonaceous materials Determination of thermal conductivity at room temperature by means of a comparative method Solids BSISO12987:2004blankBS ISO 12987:2004 BSI 389 Chiswick High Road London W4 4AL BSI British Standards Institution BSI is the independent national body responsible for preparing British Standards. It presents the UK view on standards in Europe and at the international level. It is incorporated by
