1、Designation: C 973 87 (Reapproved 2009)Standard Practice forPreparing Test Specimens From Basic Refractory GunningProducts by Pressing1This standard is issued under the fixed designation C 973; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、 revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers a procedure for preparing testspecimens from basic refractory gunning prod
3、ucts by pressingprepared material in a mold. After pressing, test specimensprepared from dolomitic mixes are subjected to a prescribedheat treatment. Specimens prepared in accordance with thisprocedure are intended for use in ASTM test methods.1.2 The values stated in inch-pound units are to be rega
4、rdedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This standard does not purport to address all of thesafety problems, if any, associated with its use. It is theresponsibility of the user
5、 of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Significance and Use2.1 This practice defines a procedure that ensures consistentpreparation of specimens for product testing and evaluation.2.2 This pra
6、ctice can be used in the laboratories of produc-ers, users, and general-interest parties for research and devel-opment or quality-control work. It is particularly useful forinterlaboratory comparisons on products, for repetitive evalu-ations or comparisons of products or product equality, and inspec
7、ifying a uniform preparation practice for specimens foracceptance testing.2.3 In using this practice, it must be recognized that thestructure of laboratory-pressed specimens may differ signifi-cantly from the structure of material gunned in field applica-tions.3. Apparatus3.1 Mixer, bench-type, Hoba
8、rt or equivalent.3.2 Press, mechanical or hydraulic.3.3 Steel Molds.3.4 Furnace.3.5 Oven, air-circulating.3.6 Desiccator.3.7 Trowel.4. Procedure4.1 Store the material to be tested at 85 6 2F (29.5 6 1C)for 24 h prior to testing. Dolomitic materials should be storedin airtight containers.4.2 Reduce t
9、he sample to the desired batch size with asample splitter or by quartering taking precautions to preventsegregation. Sufficient material should be batched to provide atleast a 10 % excess over test specimen requirements.4.3 Add the weighed, dry batch to the mixer and dry-mix atlow speed for 30 s. Co
10、ntinue to mix at low speed while addingthe required amount of water (see 4.3.1) within 30 s. Wet-mixat low speed for 3 min.4.3.1 Use the amount of water and mixing time (if differentfrom above) recommended by the manufacturer. The watermust be potable and at a temperature of 85 6 2F (29.5 61C). Meas
11、ure the water addition to the nearest 0.1 % byweight.4.4 Specimens of the desired size should be pressed imme-diately after the batch is mixed. Weigh the proper amount ofmaterial (see 4.4.1) for each specimen to the nearest 0.02 lb (10g), and distribute the mix uniformly in the mold using thenarrow
12、edge of a trowel. (The remainder of the batch should becovered with a damp cloth during the pressing procedure).Press test specimens at 1800 psi (12.41 MPa).4.4.1 Some products contain hydratable materials (for ex-ample, dead-burned dolomite) or quick-setting bonds, or both,that tend to react during
13、 the course of pressing severalspecimens from a single wet-mixed batch. Because of thisreaction, the physical properties of specimens pressed near thebeginning of a batch may differ from those of specimenspressed near the end. Products of these types should be mixedin small batches to minimize this
14、effect.4.5 Test specimens prepared from mixes that do not containdolomite should be air-dried for 4 h, and then dried for aminimum of8hat2256 5F (107 6 2.5C) in a circulatingair dryer prior to testing. Testing should be carried out within48 h.1This practice is under the jurisdiction ofASTM Committee
15、 C08 on Refractoriesand is the direct responsibility of Subcommittee C08.09 on Monolithics.Current edition approved March 1, 2009. Published April 2009. Originallyapproved in 1982. Last previous edition approved in 2004 as C 973 87 (2004).1Copyright ASTM International, 100 Barr Harbor Drive, PO Box
16、C700, West Conshohocken, PA 19428-2959, United States.4.6 Test specimens prepared from dolomitic mixes requirespecial handling to prevent hydration. Place the test specimensin a furnace at 1830F (1000C) immediately after pressingand soak for a minimum of 2 h. Then remove them from thefurnace before
17、it has cooled below 1100F (593C), cool in airfor a maximum of 2 h, and store in a desiccator or nitrogen-purged box prior to testing. Testing must be performed within48 h, taking precautions to prevent hydration.5. Calculation and Report5.1 In the report on specimen preparation, include thepercent w
18、ater addition, drying time, and test specimen size.ASTM 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 advised that determination of the validity of any such patent righ
19、ts, 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 reapproved or withdrawn. Your comments are invited either for
20、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 you feel that your comments have not received a fair hearing
21、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. Individual 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).C 973 87 (2009)2
