1、Designation: C 830 00 (Reapproved 2006)Standard Test Methods forApparent Porosity, Liquid Absorption, Apparent SpecificGravity, and Bulk Density of Refractory Shapes by VacuumPressure1This standard is issued under the fixed designation C 830; the number immediately following the designation indicate
2、s the year oforiginal adoption or, in the case of revision, the 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.1. Scope1.1 These test methods cover the determination of
3、 thefollowing properties of refractory shapes:1.1.1 Apparent porosity,1.1.2 Liquid absorption,1.1.3 Apparent specific gravity, and1.1.4 Bulk density.1.2 These test methods are applicable to all refractoryshapes except those that chemically react with both water andmineral spirits. When testing a mat
4、erial capable of hydration orother chemical reaction with water but which does not chemi-cally react with mineral spirits, mineral spirits is substituted forwater and appropriate corrections for the density differencesare applied when making calculations.1.3 The values stated in inch-pound units are
5、 to be regardedas the standard. The values given in parentheses are providedfor information only.1.4 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
6、practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1Test Methods C20cover procedures for testing properties ofrefractories that are not attacked by water.2. Referenced Documents2.1 ASTM Standards:2C20 Test Methods for Apparent Porosity, Water Absorp-tion, Apparent
7、 Specific Gravity, and Bulk Density ofBurned Refractory Brick and Shapes by Boiling WaterC 134 Test Methods for Size, Dimensional Measurements,and Bulk Density of Refractory Brick and InsulatingFirebrickE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method
8、3. Significance and Use3.1 Apparent porosity, water absorption, apparent specificgravity, and bulk density are primary properties of refractoryshapes. These properties are widely used in the evaluation andcomparison of product quality and as part of the criteria forselection and use of refractory pr
9、oducts in a variety ofindustrial applications. These test methods are used for deter-mining any or all of these properties and are particularly usefulfor testing hydratable products.3.2 These test methods are primary standard methods thatare suitable for use in quality control, research and develop-
10、ment, establishing criteria for and evaluating compliance withspecifications, and providing data for design purposes.3.3 Fundamental assumptions inherent in these test methodsare:3.3.1 The test specimens conform to the requirements forsize, configuration, and original faces,3.3.2 The open pores of t
11、he test specimens are fully impreg-nated with liquid during the vacuum-pressure treatment, and3.3.3 The blotting of the saturated test specimens is per-formed as specified in a consistent and uniform manner toavoid withdrawing liquid from the pores.3.3.4 Deviation from any of these assumptions adver
12、selyaffects the test results.3.4 In laboratory studies involving castable specimen, a biaswas noted between formed2X2X2in (50 X 50 X 50mm)and specimens quartered from larger 9 X 4.5 X 2.5in (228 X114 X 64mm) cast specimens. Additionally, an error in theapparent porosity determination was found on ca
13、stables when-ever the specimens were heated to 1500F (816C) and thenexposed to water as a saturation media. The error wasattributed to reactivity of cement with water and subsequentre-hydration of cement phases. The higher the cement level ofthe castable, the greater the error noted. It was conclude
14、d thatan error in porosity values could occur for refractory materialshaving a potential to form hydrated species with water. Testing1These test methods are under the jurisdiction of ASTM Committee C08 onRefractories and are the direct responsibility of Subcommittee C08.03 on PhysicalProperties.Curr
15、ent edition approved June 1, 2006. Published June 2006. Originallyapproved in 1976. Last previous edition approved in 2000 as C 830 00.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inf
16、ormation, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.under the same conditions in kerosene produced results thatwere believed to be more accurate, but the data sugg
17、ested thatthe kerosene might not have saturated the open pores of castspecimen as readily as water. Supporting data were filed atASTM headquarters and can be obtained by requesting re-search report 1014.3.5 Certain precautions must be exercised in interpretingand using results from these test method
18、s. All four propertyvalues are interrelated by at least two of the three base datavalues generated during testing. Thus, an error in any base datavalue will cause an error in at least three of the property valuesfor a given test specimen. Certain of the properties, that is,apparent specific gravity
19、and bulk density, are functions ofother factors such as product composition, compositionalvariability within the same product, impervious porosity, andtotal porosity. Generalizations on or comparisons of propertyvalues should be judiciously made between like products testedby these test methods or w
20、ith full recognition of potentiallyinherent differences between the products being compared orthe test method used.3.6 When a liquid other than water is used, such as types ofkerosene or mineral spirits, specific gravity must be known byeither determination or monitoring on a controlled basis.Specif
21、ic gravity will change due to different grades of liquids,evaporation, or contamination with dirt or foreign material.The test should not be run if the liquid becomes dirty, foamy,or changes color, because foreign particles can block pores andprevent impregnation of the sample.4. Test Specimens4.1 W
22、hen testing 9-in. (228-mm) straight brick, use aquarter-brick specimen obtained by halving the brick along aplane parallel to the 9 by 212 or 3-in. (228 by 64 or 76-mm)face and along a plane parallel to the 412 by 212 or 3-in. (114by 64 or 76-mm) face. Four of the surfaces of the resultantquarter-br
23、ick specimen include part of the original moldedfaces.4.2 When testing other refractory shapes, cut drill, or breakfrom each shape a specimen having a volume of approximately25 to 30 in.3(410 to 490 cm3). The specimen shall includeinterior and exterior portions of the shape.4.3 Remove all loosely ad
24、hering particles from each speci-men.5. Procedures5.1 Determination of Dry Weight, D:5.1.1 Dry the test specimens to constant weight by heatingto 220 to 230F (105 to 110C) and determine the dry weight,D, in grams to the nearest 0.1 g.5.1.2 The drying procedure may be omitted only when thetest specim
25、ens are known to be dry, as may be the case withsamples taken directly from kilns.5.1.3 The drying of the specimens to constant weight andthe determination of their dry weight may be done either beforeor after the saturation operation (5.2). Usually, the dry weightis determined before saturation; if
26、, however, the specimens arefriable or evidence indicates that particles have broken looseduring the saturating operation, dry and weigh the specimensafter the suspended weight, S, and the saturated weight, W,have been determined as described in 5.3 and 5.4. Use thissecond dry weight in all appropri
27、ate calculations.5.2 SaturationPlace the test specimens in a suitablevacuum-pressure vessel (Note 2) which shall be closed, se-cured, and pumped down to an absolute pressure of not morethan 1.9 in. Hg (6.4 kPa). Hold this pressure for 30 min.Allowthe water or mineral spirits (see 1.2) to enter the v
28、essel whilemaintaining the vacuum for 5 min. Then close the vacuum lineand pressurize the vessel by means of compressed air or apressure pump. Maintain this pressure at 30 psi (207 kPa) ormore for 60 min. Then release the pressure; the saturatedspecimens are now ready for weighing.NOTE 2The vacuum-p
29、ressure vessel should be capable of withstand-ing an absolute pressure of 1.0 in. Hg (3.4 kPa) or a pressure of 65 to 70psi (448 to 483 kPa) without deforming or rupturing. It should be providedwith gages or manometers for indicating vacuum or pressure and a reliefvalve, as well as vacuum, pressure,
30、 and liquid lines. The liquid may beintroduced at the bottom, in which case a dual-acting valve will suffice forboth filling and draining the vessel.5.3 Determination of Suspended Weight, S:5.3.1 Determine the weight, S, of each test specimen ingrams to the nearest 0.1 g after saturation and while s
31、uspendedin liquid.5.3.2 This weighing is usually accomplished by suspendingthe specimen in a loop or halter of AWG Gage-22 (0.643-mm)copper wire hung from one arm of the balance. The balanceshall be previously counter-balanced with the wire in place andimmersed in liquid to the same depth as is used
32、 when therefractory specimens are in place.5.4 Determination of Saturated Weight, WAfter determin-ing the suspended weight, blot each specimen lightly with amoistened smooth linen or cotton cloth to remove all drops ofliquid from the surface, and determine the saturated weight, W,in grams to the nea
33、rest 0.1 g by weighing in air. Perform theblotting operation by rolling the specimen lightly on the wetcloth, which has previously been saturated with liquid, andthen press only enough to remove such liquid as will drip fromthe cloth. Excessive blotting will induce error by withdrawingliquid from th
34、e pores of the specimen.5.5 Determination of Exterior Volume, VObtain the vol-ume, V, of the test specimens in cubic centimetres by subtract-ing the suspended weight from the saturated weight, both ingrams, as follows:V,cm35 W 2 S(1)NOTE 3This assumes that 1 cm3of water weighs 1 g. This is truewithi
35、n about 3 parts in 1000 for water at room temperature.NOTE 4When substituting mineral spirits for water, make the follow-ing correction:V,cm35 W 2 S!/density of liquid(2)5.6 Determination of Volume of Open Pores and ImperviousPortionsCalculate the volume of both the open pores and theimpervious port
36、ions of the specimen as follows:Volume of open pores, cm35 W 2 D (3)C 830 00 (2006)2Volume of impervious portion, cm35 D 2 S (4)NOTE 5When substituting mineral spirits for water, make the follow-ing corrections:Volume of open pores, cm35 W 2 D!/ density of liquid (5)Volume of impervious portion, cm3
37、5 D 2 S!/density of liquid(6)6. Calculation6.1 As noted in 1.2, when mineral spirits is substituted forwater, appropriate corrections for the density difference be-tween the liquids are required in the calculations. Thus, theequations used when the liquid is mineral spirits differ fromthose used whe
38、n the liquid is water. To avoid confusion andintermingling of equations, the calculations used for eachliquid are presented in separate sections (see Sections 7 and 8).6.2 When the liquid is water, calculation of the variousvolumes and properties is straightforward, as in Test MethodsC20. The assump
39、tion is taken that 1 cm3of water weighs 1 g.This is true within about 3 parts per 1000 at room temperature.Therefore, no corrections for change in water density withchange in temperature are applied in any calculations. How-ever, use of the 1 g/cm3factor is implicit in all calculationswhere direct w
40、eight measurements are converted to volumes.This affects expression of the results in the proper unit ofmeasure, that is, cm3.6.3 When the liquid is mineral spirits, correction for thedensity difference between mineral spirits and water is requiredin all calculations where direct weight measurements
41、 areconverted to volumes. The correction factor is:density of liquid (g/cm3)Use of this factor in calculations also affects expression ofthe results in the proper unit of measure, that is, g/cm3.7. Calculation When Liquid is Water7.1 Volume Calculations:7.1.1 Determination of Exterior Volume, VThe e
42、xteriorvolume of the test specimen is its bulk volume, including allsolid material, open pores, and impervious portions. CalculateV in cubic centimetres by subtracting the suspended weightfrom the saturated weight, both in grams, as follows:V,cm35 W 2 S(7)7.1.2 Determination of Volume of Open Pores
43、and Volumeof Impervious PortionsCalculate the volume of open poresand the volume of impervious portions in the test specimen incubic centimetres as follows:Volume of open pores, cm35 W 2 D (8)Volume of impervious portions, cm35 D 2 S (9)7.2 Property Calculations:7.2.1 Apparent Porosity, PThe apparen
44、t porosity ex-presses as a percentage the relationship of the volume of openpores in the test specimen to its exterior volume. Calculate P asfollows:P ,%5 W 2 D!/V# 3 100(10)7.2.2 Water Absorption, Aw The water absorption ex-presses as a percentage the relationship of the weight of waterabsorbed to
45、the weight of the dry test specimen. Calculate Awas follows:Aw,% 5 W 2 D!/D# 3 100(11)7.2.3 Apparent Specific Gravity, TThe apparent specificgravity of the test specimen is the quotient of its dry weightdivided by its volume of impervious portions. Since the resultexpresses a type of specific gravit
46、y value, it is given that thevalue obtained for T has already been divided by the assumeddensity of water, thereby rendering the result unitless. Calcu-late T as follows:T 5 D/D 2 S(12)7.2.4 Bulk Density, BThe bulk density of the test speci-men in grams per cubic centimetre is the quotient of its dr
47、yweight divided by its exterior volume. Calculate B as follows:B, g/cm35 D/ V(13)NOTE 6This test method for determining bulk density is useful forchecking bulk density values obtained by the direct measurement methoddescribed in Test Methods C 134. While this test method is more accuratethan the dir
48、ect measurement method, the latter is better suited for plantand field testing since it is a less involved technique. The present testmethod is preferable for specimens that are deeply branded or are irregularin contour.8. Calculation When Liquid Is Mineral Spirits8.1 The calculations when the liqui
49、d is mineral spirits arepresented below without commentary or explanation exceptwhere these are essential to understand a particular calculation.However, the commentary, explanations, and Note 6 given inSection 7 for calculations when the liquid is water are fullyapplicable here also.8.1.1 When the term liquid appears in any of the calcula-tions below, it means mineral spirits.8.1.2 When the density of water is used in any of thecalculations below, it is still assumed to be 1 g/cm3.8.2 Volume Calculations:8.2.1 Determination of Exterior Volume, VCal
