1、Designation: C 562 91 (Reapproved 2005)An American National StandardStandard Test Method forMoisture in a Graphite Sample1This standard is issued under the fixed designation C 562; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, th
2、e year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method provides
3、a practical determination forthe percentage of moisture in a graphite sample.1.2 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determ
4、ine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 561 Test Method for Ash in a Graphite Sample3. Significance and Use3.1 This test method is feasible only for the volatile mois-ture present on the graphite due to adsorption from theatmosphere
5、and is not intended to give representative moisturedata for graphite that has been exposed to liquid watercontamination.4. Interferences4.1 Final weights (and therefore percent moisture values)may be influenced by the following:4.1.1 Type and condition of desiccant.4.1.2 Ambient relative humidity at
6、 the time of the test.4.1.3 Timing and procedure for moving samples from des-iccator to the balance.4.1.4 Adsorptivity of the graphite sample relative to theadsorptivity of the desiccant used.4.1.5 Residency time in the desiccator.5. Apparatus5.1 Alumina Ceramic or Platinum Crucible or Dish, suit-ab
7、le for holding sample (subsequently called sample holder).5.2 Analytical Balance, capable of weighing to 60.0002 g.5.3 Drying Oven, air convection type, capable of beingcontrolled to 110 6 2C (2306 4F).5.4 Desiccator, charged with indicating desiccant.6. Sampling6.1 Samples may be solid or particula
8、te. Solid bodies maybe sampled by removing one or more solid pieces from thebody by, for example, sawing, turning, milling, or fracturing.Particulate samples may be generated from solid bodies bydrilling, using a carbide drill to minimize contamination, or byother crushing and grinding methods.7. Pr
9、ocedure7.1 Tare a dried sample holder using an analytical balance.Weigh a 25 to 50-g sample into the tared sample holder andreweigh both. (Perform all weighings to a precision of60.002 g.)7.2 Place the sample holder containing the sample in adrying oven maintained at 110 6 2C (230 6 4F) for 2 h.Remo
10、ve from the oven and immediately place in the desicca-tor. When the sample has reached room temperature, removefrom the desiccator and weigh immediately.7.3 Repeat the procedure prescribed in 7.2 until a constantweight of 60.002 g is achieved.7.4 The dried sample may be reserved for ash determina-ti
11、on. (See Test Method C 561.)8. Calculation8.1 Calculate the percentage of moisture as follows:Moisture, % 5 B 2 C!/B 2 A!# 3 100where:A = weight of sample holder,B = weight of sample holder and sample, andC = weight of sample holder and dried sample.1This test method is under the jurisdiction of AST
12、M Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.F0 on Manufactured Carbon and Graphite Products.Current edition approved June 1, 2005. Published August 2005. Originallyapproved in 1965. Last previous edition approved in 2000 as C 56291(2000).2F
13、or referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C7
14、00, West Conshohocken, PA 19428-2959, United States.9. Report9.1 The report shall include the following information:9.1.1 Proper identification of the sample, and9.1.2 Results obtained from at least two moisture determi-nations, and their average.10. Precision and Bias310.1 The precision of this tes
15、t method was determinedduring a round-robin test among four laboratories testingsamples split from a common sample which was ground to passa No. 60 (250 m) sieve. This sampling method was used forthe round robin to minimize variations among samples pro-vided to participating laboratories.10.2 On thi
16、s sample the mean, standard deviation betweenlaboratories and standard deviation within laboratories were,respectively:Mean 0.0155Between laboratories 0.0143Within laboratories 0.003710.3 No bias was noted during the round-robin test; how-ever, the method is empirical and there is no suitable refere
17、ncematerial that can be used to determine the bias of this testmethod.11. Keywords11.1 carbon; graphite; moistureASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advi
18、sed that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either
19、reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If
20、 you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individ
21、ual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:C05-1008.C 562 91 (2005)2
