1、Designation: C830 00 (Reapproved 2011)Standard Test Methods forApparent Porosity, Liquid Absorption, Apparent SpecificGravity, and Bulk Density of Refractory Shapes by VacuumPressure1This standard is issued under the fixed designation C830; the number immediately following the designation indicates
2、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 () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover the determination of th
3、efollowing 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 materi
4、al 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 UnitsThe values stated in inch-pound units a
5、re to beregarded as standard. The values given in parentheses aremathematical conversions to SI units that are provided forinformation only and are not considered standard.1.3.1 ExceptionThe apparatus used in this standard isonly available in SI units.1.4 This standard does not purport to address al
6、l 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 determine the applica-bility of regulatory limitations prior to use.NOTE 1Test Methods C20 cover procedures for testing properties
7、ofrefractories that are not attacked by water.2. Referenced Documents2.1 ASTM Standards:2C20 Test Methods forApparent Porosity, WaterAbsorption,Apparent Specific Gravity, and Bulk Density of BurnedRefractory Brick and Shapes by Boiling WaterC134 Test Methods for Size, Dimensional Measurements,and Bu
8、lk Density of Refractory Brick and InsulatingFirebrickE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Significance and Use3.1 Apparent porosity, water absorption, apparent specificgravity, and bulk density are primary properties of refractoryshapes.
9、 These properties are widely used in the evaluation andcomparison of product quality and as part of the criteria forselection and use of refractory products in a variety ofindustrial applications. These test methods are used for deter-mining any or all of these properties and are particularly useful
10、for testing hydratable products.3.2 These test methods are primary standard methods thatare suitable for use in quality control, research and develop-ment, establishing criteria for and evaluating compliance withspecifications, and providing data for design purposes.3.3 Fundamental assumptions inher
11、ent 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 the test specimens are fully impreg-nated with liquid during the vacuum-pressure treatment, and3.3.3 The blotting of the saturated test specimens is pe
12、r-formed as specified in a consistent and uniform manner toavoid withdrawing liquid from the pores.3.3.4 Deviation from any of these assumptions adverselyaffects the test results.3.4 In laboratory studies involving castable specimen, a biaswas noted between formed 2 3 2 3 2 in. (50 3 50 3 50 mm)and
13、specimens quartered from larger 9 3 4.5 3 2.5 in. (228 3114 3 64 mm) cast specimens. Additionally, an error in theapparent porosity determination was found on castables when-ever the specimens were heated to 1500F (816C) and thenexposed to water as a saturation media. The error wasattributed to reac
14、tivity of cement with water and subsequentre-hydration of cement phases. The higher the cement level ofthe castable, the greater the error noted. It was concluded that1These test methods are under the jurisdiction of ASTM Committee C08 onRefractories and are the direct responsibility of Subcommittee
15、 C08.03 on PhysicalProperties.Current edition approved July 1, 2011. Published July 2011. Originally approvedin 1976. Last previous edition approved in 2006 as C830 00 (2006)1. DOI:10.1520/C0830-06R11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Servi
16、ce 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 C700, West Conshohocken, PA 19428-2959, United States.an error in porosity values could occur for r
17、efractory materialshaving a potential to form hydrated species with water. Testingunder the same conditions in kerosene produced results thatwere believed to be more accurate, but the data suggested thatthe kerosene might not have saturated the open pores of castspecimen as readily as water.33.5 Cer
18、tain precautions must be exercised in interpretingand using results from these test methods. 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 valu
19、esfor a given test specimen. Certain of the properties, that is,apparent specific gravity 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 proper
20、tyvalues should be judiciously made between like products testedby these test methods or with 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, specif
21、ic gravity must be known byeither determination or monitoring on a controlled basis.Specific 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 fore
22、ign particles can block pores andprevent impregnation of the sample.4. Test Specimens4.1 When 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
23、 by 212 or 3-in. (114by 64 or 76-mm) face. Four of the surfaces of the resultantquarter-brick 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 s
24、pecimen shall includeinterior and exterior portions of the shape.4.3 Remove all loosely adhering 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 gra
25、ms to the nearest 0.1 g.5.1.2 The drying procedure may be omitted only when thetest specimens 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
26、the saturation operation (5.2). Usually, the dry weightis determined before saturation; if, 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,h
27、ave been determined as described in 5.3 and 5.4. Use thissecond dry weight in all appropriate 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)
28、. Hold this pressure for 30 min. Allowthe water or mineral spirits (see 1.2) to enter the vessel 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
29、 release the pressure; the saturatedspecimens are now ready for weighing.NOTE 2The vacuum-pressure 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 m
30、anometers for indicating vacuum or pressure and a reliefvalve, as well as vacuum, pressure, 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
31、 weight, S, of each test specimen ingrams to the nearest 0.1 g after saturation and while suspendedin 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
32、 counter-balanced with the wire in place andimmersed in liquid to the same depth as is used 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
33、 drops ofliquid from the surface, and determine the saturated weight, W,in grams to the nearest 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
34、 will drip fromthe cloth. Excessive blotting will induce error by withdrawingliquid from the 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
35、 follows:V,cm35 W 2 S(1)NOTE 3This assumes that 1 cm3of water weighs 1 g. This is truewithin 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)3Supporting data have been filed at AST
36、M International Headquarters and maybe obtained by requesting Research Report RR:C08-1014.C830 00 (2011)25.6 Determination of Volume of Open Pores and ImperviousPortionsCalculate the volume of both the open pores and theimpervious portions of the specimen as follows:Volume of open pores, cm35 W 2 D
37、(3)Volume 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, cm35 D 2 S!/density of liquid(6)6. Calculation6.1 As noted in 1.2, when mineral spir
38、its 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 when the liquid is water. To avoid confusion andintermingling of equations, the calc
39、ulations 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 assumption is taken that 1 cm3of water weighs 1 g.This is true within about 3 parts per
40、 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 weight measurements are converted to volumes.This affects expression of the result
41、s 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 areconverted to volumes. The correction factor is:density of liquid (g/cm3)Use o
42、f 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 exteriorvolume of the test specimen is its bulk volume, including allsolid materia
43、l, 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 and Volumeof Impervious PortionsCalculate the volume of open poresand the volume
44、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 apparent porosity ex-presses as a percentage the relationship of the volume of openpores
45、 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 the weight of the dry test specimen. Calculate Awas follows:Aw,% 5 W 2 D!/D# 3 10
46、0(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 gravity value, it is given that thevalue obtained for T has already been divided by the
47、 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 dryweight divided by its exterior volume. Calculate B as follows:B, g/cm35 D/ V(13)
48、NOTE 6This test method for determining bulk density is useful forchecking bulk density values obtained by the direct measurement methoddescribed in Test Methods C134. While this test method is more accuratethan the direct measurement method, the latter is better suited for plantand field testing sin
49、ce 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 liquid 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 calc
