1、Designation: C 704 01e1Standard Test Method forAbrasion Resistance of Refractory Materials at RoomTemperature1This standard is issued under the fixed designation C 704; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.e1NOTEAdjunct references were corrected editorially in April 2006.1. Scope1.1 This test method covers the determination of relative
3、abrasion resistance of refractory brick at room temperature.This test method can also be applied to castable refractories(see Metric Dimensions C 861 and Practice C 865) and plasticrefractories (see Practice C 1054).1.2 The values stated in SI units are to be regarded as thestandard. The values give
4、n in parentheses are provided forinformation only.1.3 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 determine the applica-bility of r
5、egulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 134 Test Methods for Size, Dimensional Measurements,and Bulk Density of Refractory Brick and InsulatingFirebrickC 179 Test Method for Drying and Firing Linear Change ofRefractory Plastic and Ramming Mix SpecimensC 861 Pr
6、actice for Determining Metric Dimensions of Stan-dard Series Refractory Brick and ShapesC 862 Practice for Preparing Refractory Concrete Speci-mens by CastingC 865 Practice for Firing Refractory Concrete SpecimensC 1054 Practice for Pressing and Drying Refractory Plasticand Ramming Mix Specimens2.2
7、ASTM Adjuncts:Abrasion Tester (1 dwg)33. Summary of Test Method3.1 This test method measures the volume of material incubic centimetres abraded from a flat surface at a right angle toa nozzle through which 1000 g of size-graded silicon carbidegrain is blasted by air at 448 kPa (65 psi).4. Significan
8、ce and Use4.1 This test method measures the relative abrasion resis-tance of various refractory samples under standard conditionsat room temperature.4.2 The abrasion resistance of a refractory material providesan indication of its suitability for service in abrasion or erosiveenvironments.4.3 The re
9、sults obtained by this test method could bedifferent than those obtained in service because of the differentconditions encountered.5. Apparatus5.1 Abrasion Tester, used for measuring the abrasion resis-tance of refractory specimens, consisting of the following (Fig.1 and Fig. 2):5.1.1 Blast Gun4, mo
10、dified for this equipment as shown inFig. 3.5.1.2 NozzleA piece of glass tubing is used to replace thesteel nozzle supplied with the sand-blast gun to permit controlof nozzle size through nozzle replacement after each determi-nation. Flint-glass tubing, 115 mm (412 in.) long, 7 mm (14 in.)in outside
11、 diameter, with a nominal 1.1 mm (116 in.) wall, isused. This piece of glass tubing is held in place by a 70 mm(234 in.) long piece of stainless steel tubing. The I.D. (insidediameter) of this tubing, which should be flared at one end to1This test method is under the jurisdiction of ASTM Committee C
12、08 onRefractories and is the direct responsibility of Subcommittee C08.03 on PhysicalTests and Properties.Current edition approved Dec. 10, 2001. Published January 2002. Originallypublished as C 704 72. Last previous edition C 704 99.2For referenced ASTM standards, visit the ASTM website, www.astm.o
13、rg, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Detailed prints for the construction of the test chamber are available at anominal cost from ASTM Headquarters. Request ADJC07
14、04. An acceptable testchamber can be made from a weatherproof electrical switch box such as aWiegmann B 20167 continuous hinge box.4The sand blast gun shown in Fig. 3, available from Leitch and Company, 971Howard St., San Francisco, CA, has been found suitable for use in this test method.1Copyright
15、ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.sit snugly inside a 9.53 mm (38 in.) tubing nut, should be 7.15mm (932 in.). The O.D. (outside diameter) should be 9.53 mm(38 in.). This sleeve is glued in place along with a rubbergrommet of prop
16、er size, inside the 9.53 mm (38 in.) tubing nut,and is used primarily to hold the glass tubing perpendicular tothe test sample, assuring a proper vacuum within the gun. Theend of the glass tube, through which the abrading media entersthe nozzle in the venturi chamber, is placed at a distance of 2mm
17、(0.08 in.) from the air-generator nozzle. This is done byplacing the glass tubing on a brass rod, 4.5 mm (0.175 in.) indiameter with a shoulder 7.9 mm (516 in.) in diameter, 117 mm(4.68 in.) from the tip. This will allow the operator to push theNOTE 1Identified by number in this figure are: (1) cabi
18、net pressure manometer, (2) dust collector vent, (3) test pressure gage, (4) grit feed tunnel,and (5) vacuum gage.FIG. 1 Abrasion TesterC70401e12glass tubing up through the rubber grommet until the rodtouches the nozzle, assuringa2mm(0.08 in.) gap between thenozzle and the glass tubing.5.1.3 Venturi
19、The air-generator nozzle should have aninlet inside diameter of from 2.84 to 2.92 mm (0.112 to 0.115in.) and an outlet inside diameter of from 2.36 to 2.44 mm(0.093 to 0.096 in.). The surface of the air-generator nozzlewithin the venturi chamber of the gun is protected from theabrading media with a
20、9.4 mm (38 in.) long piece of vinyltubing 4.7 mm (316 in.) inside diameter with a 1.5 mm (116 in.)wall thickness. The inside diameter of the venturi chambershould not exceed 10 mm (38 in.) and should be checkedperiodically for wear.5.1.4 Air SupplyThe air line pressure shall be maintainedat the desi
21、red pressure at the gun through the use of a standardsuppressed range air gage indicating 6.9 kPa (61 psi) mountedas close to the gun as possible. Only clean dry air should beused.NOTE 1Identified by number in this figure are: (1) sand blast gun, (2) air pressure regulator, (3) glass tube and metal
22、stabilizing sleeve, (4) test sample,and (5) adjustable platform.FIG. 2 Abrasion TesterC70401e135.1.5 Abrading MediaNo. 36 grit silicon carbide having ascreen analysis as shown in Table 1.5.1.6 Feeding MechanismTwo acceptable mechanismsfor feeding the abrading media are shown in Fig. 4. The feedfunne
23、l must contain a suitable orifice to obtain a flow time of4506 15 s while delivering 1000 g of abrading media into thegun supply funnel. Metal, glass, or plastic orifices can be usedto regulate the flow. There must be an air gap between theorifice and the gun supply funnel to allow secondary air toe
24、nter with the abrading media.5.1.7 Test Chamber, consisting of a tightly sealed closurewith a door to permit ready access for mounting and removingthe test specimens.A 13-mm (12-in.) hole shall be cut in the topof the test chamber to permit the vertical mounting of the blastgun such that the downwar
25、d stream of abrading media willtravel 203 mm (8 in.) from the glass nozzle tip to the testspecimen. Fig. 1 and Fig. 2 show the design of an acceptablechamber.35.1.7.1 Dust CollectorA standard dust-collecting clothbag of adequate capacity may be used on the 52 mm (2116-in.)exhaust port of the chamber
26、. This port is equipped with abutterfly valve to regulate the pressure in the chamber duringthe test. Alternate dust handling systems are acceptable as longas the chamber pressure is maintained at the desired level.5.1.7.2 ManometerDuring the test the chamber pressureshall be measured with a water m
27、anometer having a scale suchthat 311 Pa (114 in.) of water may be readily measured. A 6mm (14-in.) inside diameter pet cock shall be mounted in thetop of the chamber to permit manometer connection.5.2 Balance, capable of weighing the sample to an accuracyof 60.1 g, used for weighing the abrading med
28、ia and testspecimens. Typically a 2000 g to 3000 g capacity balance isrequired.6. Test Specimens6.1 Test specimens shall be cut from refractory brick orshapes, or molded from monolithic refractory materials andmeasure from 100 by 100 by 25 mm (4 by 4 by 1 in.) to 114by114by65or76mm(412 by 412 by 212
29、 or 3 in.). Only theNOTE 1Identified by number in this figure are: (1) glass tube adjustment rod, (2) metal stabilizing sleeve, (3) glass tube with grommet, and (4) sandblast gun.FIG. 3 Modified Blast Gun BreakdownTABLE 1 Screen Analysis for Abrading MediaASTM Standard Sieve No. Opening, m Retained,
30、 %20 850 trace30 600 206 250 300 806 370 212 2 maxPass No. 70 traceC70401e14most abrasion resistant materials can be 25 mm (1 in.) thicksince the test is invalid if a hole is eroded completely throughthe specimen.6.2 Castable refractories shall be molded in accordance withPractice C 862 and fired to
31、 anticipated service temperatures inaccordance with Practice C 865.NOTE 1Identified by number in this figure are: (1) main supply funnel with metering insert, (2) gun supply funnel, (3) main supply funnel, (4)metering funnel, and (5) gun supply funnel.FIG. 4 Feeding MechanismsC70401e156.3 Plastic re
32、fractories shall be molded and fired to antici-pated service temperature in accordance with Test MethodC 179 (see the sections on apparatus and test specimens).7. Procedure7.1 Dry the test specimens to a constant weight at 105 to110C (220 to 230F) before testing.7.2 Weigh the specimens to the neares
33、t 0.1 g. Determine thevolume of the specimens by measurement of length, width, andthickness to the nearest 0.5 mm (150 in.) in accordance with theapparatus section of Test Methods C 134.7.3 Place the nominal 114 by 114 mm (412 by 412 in.) faceof the test specimens at a 90 angle to the glass nozzle w
34、ith theunbranded surface to be abraded 203 mm (8 in.) from the tip ofthe glass nozzle. With monolithic refractory specimens, thesurface (that is, top troweled face or bottom mold face) thatmost accurately reflects the actual field situation should be thetest surface.7.4 Turn on the air pressure and
35、regulate it to 448 kPa (65psi). Check the air pressure before and after the abrading mediais run through the system.7.5 Measure the cabinet pressure using the water manom-eter and maintain the pressure in the chamber at 311 Pa (114in.) of water by means of the butterfly valve in the exhaustvent.7.6
36、After the air pressure to the gun and the chamberpressure have been adjusted, disconnect the media line to thegun and place a 30 in. of mercury vacuum gauge in position. Ifthe vacuum gauge does not show a minimum of 15 in. ofmercury, check the position of the glass tubing or the conditionof the air-
37、generator nozzle. After obtaining the proper vacuumpressure, reconnect the feed tube and recheck the cabinetpressure before placing 1000 6 5 g of dry abrading media inthe reserve funnel. The feed funnel to the gun must not fillcompletely or flood with material. The feed mechanism whenconnected with
38、the test apparatus must deliver the abradingmedia in the specified time of 450 6 15 s.7.7 Use the silicon carbide abrading media no more than 5times before discarding. Remove the material retained on No.20 (850-m) and passing No. 50 (300-m) sieves after eachrun.7.8 Remove the refractory specimens fr
39、om the test chamber,blow off the dust, and weigh to the nearest 0.1 g.8. Calculation and Report8.1 From the weight and volume, calculate the bulk densityof the specimens in grams per cubic centimetre.8.2 Calculate the amount of refractory lost by each speci-men by abrasion in cubic centimetres, A, a
40、s follows:A 5 M12 M2!/B# 5 M / Bwhere:B = bulk density, grams per cubic centimetre,M1= weight of specimen before testing, g,M2= weight of specimen after testing, g, andM = weight loss of specimen, g.8.3 Report the average of the individual results as theabrasion loss for that sample.8.4 Record and r
41、eport the time required for 1000 g ofabrading media to flow through the gun.8.5 Report which surface was abraded.9. Precision and Bias9.1 Interlaboratory Test DataAn interlaboratory studywas completed among eight laboratories in 1999. Five differenttypes of refractories, along with a plate glass sta
42、ndard, weretested for abrasion resistance by each laboratory. The five typesof refractories were a high-alumina brick, a silica brick, anabrasion-resistant castable, a super-duty fire brick, and aconventional high-cement castable. All specimens were 4.5 by4.5 in. in cross section. Additionally, both
43、 castables were firedto 1500C. Prior to testing, bulk density and sonic velocitywere measured on all specimens to ensure uniformity. Speci-mens were then randomly selected for distribution to theparticipating laboratories.9.2 PrecisionTable 2 contains the precision statistics forthe abrasion resista
44、nce results.9.2.1 RepeatabilityThe maximum permissible differencedue to test error between two test results obtained by oneoperator on the same material using the same test equipment isgiven by the repeatability interval (r) and the relative repeat-ability interval (%r). The 95 % repeatability inter
45、vals are givenin Table 2. Two test results that do not differ by more than therepeatability interval will be considered to be from the samepopulation; conversely, two test results that do differ by morethan the repeatability interval will be considered to be fromdifferent populations.9.2.2 Reproduci
46、bilityThe maximum permissible differ-ence due to test error between two test results obtained by twooperators in different laboratories on the same material usingthe same test equipment is given by the reproducibility interval(R) and the relative reproducibility interval (%R). The 95 %reproducibilit
47、y intervals are given in Table 2. Two test resultsthat do not differ by more than the reproducibility interval willTABLE 2 Precision Statistics for Abrasion ResistanceMaterialAverageVolumeLoss, cm3StandardDeviationWithinLabora-tories, SrStandardDeviationBetweenLabora-tories, SRRepeat-abilityInterval
48、, rReproduc-bilityInterval, RCoefficientof Varia-tion WithinLabora-tories, VrCoefficientof Varia-tion BetweenLabora-tories, VRRelativeRepeat-ability, %rRelativeReproduc-ibility, %RHigh-alumina brick 4.19 0.39 0.71 1.08 1.98 9.22 16.85 25.80 47.19Silica brick 22.17 2.64 4.62 7.40 12.95 11.91 20.86 33
49、.36 58.41Abrasion-resistant castable 8.36 0.87 1.89 2.42 5.29 10.35 22.59 28.99 63.24Super-duty firebrick 25.48 4.25 7.81 11.90 21.86 16.68 30.64 46.70 85.80Conventional high-cement castable 10.89 2.12 3.02 5.94 8.45 19.48 27.71 54.54 77.59Plate Glass Standard 9.28 0.34 1.51 0.95 4.23 3.66 16.27 10.24 45.58C70401e16be considered to be from the same population; conversely, twotest results that do differ by more than the reproducibilityinterval will be considered to be from different populations.9.3 BiasNo justifiable statement can
