1、Designation: C973 87 (Reapproved 2015)Standard Practice forPreparing Test Specimens From Basic Refractory GunningProducts by Pressing1This standard is issued under the fixed designation C973; the number immediately following the designation indicates the year oforiginal adoption or, in the case of r
2、evision, 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 produc
3、ts 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 regard
4、edas 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 o
5、f 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 pract
6、ice can be used in the laboratories ofproducers, users, and general-interest parties for research anddevelopment or quality-control work. It is particularly usefulfor interlaboratory comparisons on products, for repetitiveevaluations or comparisons of products or product equality,and in specifying a
7、 uniform preparation practice for specimensfor acceptance 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, Hobart or eq
8、uivalent.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 the sampl
9、e 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. Continue t
10、o 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). Measure the
11、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 edge of
12、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 (forexample, dead-burned dolomite) or quick-setting bonds, orboth, that tend to react during the cours
13、e 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 effect.4.5
14、 Test specimens prepared from mixes that do not containdolomite should be air-dried for 4 h, and then dried for a1This practice is under the jurisdiction ofASTM Committee C08 on Refractoriesand is the direct responsibility of Subcommittee C08.09 on Monolithics.Current edition approved Oct. 1, 2015.
15、Published October 2015. Originallyapproved in 1982. Last previous edition approved in 2009 as C973 87 (2009).DOI: 10.1520/C0973-87R15.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1minimum of8hat2256 5F (107 6 2.5C) in a circulatinga
16、ir dryer prior to testing. Testing should be carried out within48 h.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 thef
17、urnace before 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, includ
18、e thepercent water 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 su
19、ch 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 reapproved or withdrawn. Your comments are invit
20、ed 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 you feel that your comments have not received a
21、 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. Individual reprints (single or multiple copies) of this
22、 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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 87 (2015)2
