Understanding refractory api 936 reading ii

$Page 1: Understanding refractory api 936 reading ii$
Charlie Chong/ Fion Zhang

Understanding REFRACTORY For API936 Personnel Certification ExaminationReading 2- The ASTMs’My Pre-exam Self Study Notes20th September 2015


Refractory for Petrochemicals









The Magical Book of Acoustic Emission


BODY OF KNOWLEDGE FORAPI936 REFRACTORY PERSONNELCERTIFICATION EXAMINATION

API certified 936 refractory personnel must have knowledge of installation, inspection, testing and repair of refractory linings. The API 936 Personnel Certification Examination is designed to identify applicants possessing the required knowledge. The examination consists of 75 multiple-choice questions; and runs for 4 hours; no reference information is permitted on the exam. The examination focuses on the content of API STD 936 and other referenced publications.


REFERENCE PUBLICATIONS:A. API Publications: API Standard 936; 3rd Edition, Nov 2008 - Refractory Installation Quality

Control Guidelines - Inspection and Testing Monolithic Refractory Linings and Materials.

B. ACI (American Concrete Institute) Publications: 547R87 - State of the art report: Refractory Concrete 547.1R89 - State of the art report: Refractory plastic and Ramming Mixes

C. ASTM Publications: C113-02 - Standard Test Method for Reheat Change of Refractory Brick C133-97 - Standard Test Methods for Cold Crushing Strength and Modulus

of Rupture of Refractories C181-09 - Standard Test Method for Workability Index of Fireclay and

High Alumina Plastic Refractories C704-01 - Standard Test Method for Abrasion Resistance of Refractory

Materials at Room Temperatures


Fion Zhang at Shanghai20th September 2015


Video Time- shotcrete refractory


■ https://www.youtube.com/watch?v=s81LE7XXZ4A&list=PLey7s_Oct4OK9-7tMIx5cp9-RjSdetDTq

Reading IIContent Study note One: ASTM C113-02 Standard Test Method for Reheat

Change of Refractory Brick Study note Two: ASTM C133-97 Standard Test Methods for Cold

Crushing Strength and Modulus of Rupture of Refractories Study note Three: Study note Four:


Study Note 1: ASTM C113-02 Standard Test Method for Reheat Change of Refractory Brick

Charlie Chong/ Fion Zhang http://cedarcanyontextiles.com/win-bigin-our-shape-shifter-challenge/bigstock-number-icons-4/

1. Scope1.1 This test method covers the determination of the permanent linear changeof refractory brick when heated under prescribed conditions.

1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

NOTE 1- Test methods incorporating additional provisions pertinent tospecific refractory materials are given in the following Test Methods: C 179, C 210, and C 605.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine theapplicability of regulatory limitations prior to use.


2. Referenced Documents2.1 ASTM Standards: C 134 Test Methods for Size, Dimensional Measurements, and Bulk

Density of Refractory Brick and Insulating Firebrick C 179 Test Method for Drying and Firing Linear Change of Refractory

Plastic and Ramming Mix Specimens C 210 Test Method for Reheat Change of Insulating Firebrick C 605 Test Method for Reheat Change of Fireclay Nozzles and Sleeves E 230 Temperature-Electromotive Force (EMF) Tables for Standardized

Thermocouples


3. Significance and Use3.1 Refractory brick and shapes of different compositions exhibit uniquepermanent linear changes after heating or reheating. This test methodprovides a standard procedure for heating various classes of refractories withappropriate heating schedules.

3.2 Linear reheat changes obtained by this test method are suitable for use in research and development, also often used to establish written specifications between producers and consumers.

3.3 Care should be exercised in selecting samples that are representative ofthe product being tested and that the schedule selected is appropriate to theproduct.


4. Apparatus4.1 Kiln, of such design that the specified heating schedule and atmospherecan be maintained throughout the heating zone.

4.2 Linear Measuring Device, capable of being read to 0.02 in. (0.5 mm) over a span of 10 in. (254 mm). (1) A hook-rule, as specified in Test Methods C 134, (2) a vernier caliper, or (3) a dial gage device may be used.

4.3 Gas Sampling and Analysis Equipment, capable of determining the (1) percent free oxygen and (2) total combustibles in the atmosphere of the test chamber.

Keywords:Hook rule, vernier caliper, dial gage% free O2, total combustible.


Captain Hook- Once Upon a Time


Hook rule


Captain Hook- Once upon a time!

Charlie C

hong/ Fion Zhang

Vernier Caliper


Vernier Caliper- Digital


Dial Gage


5. Test Specimens5.1 For each test use three rectangular specimens measuring 9 by 4½ by 2½or 3 in. (228mm x 114mm x 64mm or 76mm) in size, or, if smaller, shapesapproaching these dimensions as closely as possible. These may becommercial brick of the specified size or test pieces cut out of larger shapes.

5.2 Using ceramic paint or crayon, label each specimen, and make areference mark at each end on the center line of a broad face to indicate theexact position where the measurement is made. Measure the length on eachof the three test specimens to the nearest 0.02 in. (0.5 mm).


9”

4½”

3 or 2½” ++

nearest 0.02 in. (0.5 mm).


9”

4½”

3 or 2½” ++

6. Procedure6.1 Placing Specimens in Kiln- Place the test specimens in the kiln so thateach rests edgewise, that is, on a 9 by 2½ or 3in. (228 by 64 or 76-mm) face and set only one course high. Place each specimen upon the corresponding face of a supporting brick that is from the same lot as the test specimen or atleast of equal refractoriness. Place between the test specimen and the supporting brick a layer of suitable refractory material, that is non- reactive under the test conditions and passing an ASTM No. 16 (1.18-mm) sieve (equivalent to a 14-mesh Tyler Standard Series) and retained on an ASTM No. 40 (425-μm) sieve (equivalent to a 35-mesh Tyler Standard Series). Place each specimen so that it is not less than 1½ in. (38 mm) from other test specimens or from the furnace wall.


≥1½ in

passing an ASTM No.16Retain ASTM No.40 sieves

ASTM Sieve


ASTM Sieve

Charlie C

hong/ Fion Zhang

6.2 Temperature Measurement- Measure the temperature within the kiln bymeans of an appropriate calibrated thermocouple. Refer to E 230, Tables 1and 2, for the tolerances and upper temperature limits for use of variousthermocouples. At higher temperatures, the thermocouple may be withdrawnand a calibrated optical or radiation pyrometer can be used. Place the hotjunction of the thermocouple or sight the pyrometer so as to register thetemperature of the test specimens. Make temperature readings at intervalsnot greater than 15 min. Check the kiln periodically by thermocouples,pyrometers or pyrometric cones to ensure that temperatures over the hearthdo not differ by more than 25°F (14°C) or one-half cone (?) .


To

T1,2,3..

∆T = To- T1,2,3, ≤ 25°F

6.3 Test Atmosphere- At all temperatures above 1470°F (800°C) the furnaceatmosphere shall contain a minimum of 0.5 % oxygen and 0 % combustibles.Take gas-analysis samples from the furnace chamber proper.

6.4 Test Temperature Schedule- Operate the kiln so as to conform to the appropriate heating schedule for the class of refractory being tested as shown in Table 1. Adjust the firing during the hold period so that the temperatures will average the specified temperature within 5°F (3°C). After completion of the heating schedule, cool the specimens in the closed kiln to below 800°F (425°C) before removing.

6.5 Measuring Fired Specimens- Remeasure the test specimens at room temperature in accordance with 4.2 after rubbing the ends with an abrasive block to remove small blisters, if necessary.


7. Calculation and Report7.1 Calculate the percentage linear change based upon the original length ofeach specimen. Report the average of the three individual values as thereheat change in the test.


specimen.

8. Precision and Bias8.1 Interlaboratory Test Data- An interlaboratory roundrobin test wasconducted between eight laboratories at three different reheat temperatures.

8.1.1 In the interlaboratory study, four types of brick were tested, threesamples each, a total of seven sets at each laboratory.

8.1.2 Heating schedules, brick types tested, averages of all determinations, and precisions are given in Table 2.

8.2 Precision- For the components of variation given in Table 2, a test result composed of three samples should be considered significantly different at a confidence level of 95 %, if the repeatability or reproducibility exceeds the precision data given in Table 2.

8.3 Bias- No justifiable statement on bias is possible since the true physical properties of refractories cannot be established by an acceptable reference material.


9. Keywords9.1 heating schedule; refractory brick; reheat change; temperaturemeasurements; test atmosphere


TABLE 1 Heating Schedule for Reheat of Various Types of Refractories


TABLE 2 Precision of Interlaboratory Test Results Relative precision does not apply since values pass through the point of zero.

NOTE- Relative precision does not apply since values pass through the point of zero.


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Applications:1. Steel furnaces2. Iron making furnaces3. Glass kiln4. Ceramic tunnel kiln5. Cement kiln

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Corundum Mullite Castable

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Study Note 2: ASTM C133-97Standard Test Methods for Cold Crushing Strength and Modulus of Rupture of Refractories


1. Scope1.1 These test methods cover the determination of the cold crushing strength and the modulus of rupture (MOR) of dried or fired refractory shapes of all types.

1.2 The test methods appear in the following sections:

Test Method Sections■ Cold Crushing Strength 4 to 9■ Modulus of Rupture 10 to 15

1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.


2. Referenced Documents2.1 ASTM Standards:• C 862 Practice for Preparing Refractory Concrete Specimens by Casting• C 1054 Practice for Pressing and Drying Refractory Plastic and Ramming

Mix Specimens• E 4 Practices for Force Verification of Testing Machines3


3. Significance and Use3.1 The cold strength of a refractory material is an indication of its suitabilityfor use in refractory construction. (It is not a measure of performance atelevated temperatures.)

3.2 These test methods are for determining the room temperature flexural strength in 3-point bending (cold modulus of rupture) or compressive strength (cold crushing strength), or both, for all refractory products.

3.3 Considerable care must be used to compare the results of different determinations of the cold crushing strength or modulus of rupture. The specimen size and shape, the nature of the specimen faces (that is, as-formed, sawed, or ground), the orientation of those faces during testing, the loading geometry, and the rate of load application, may all significantly affect the numerical results obtained. Comparisons of the results between different determinations should not be made if one or more of these parameters differ between the two determinations.


Factors Affecting Test Results1. The specimen size and shape, 2. the nature of the specimen faces (that is, as- formed, sawed, or ground), 3. the orientation of those faces during testing, 4. the loading geometry, and the 5. rate of load application, 6. The relative ratio of the largest grain size to the smallest specimen

dimension

may all significantly affect the numerical results obtained. Comparisons of the results between different determinations should not be made if one or more of these parameters differ between the two determinations.


3.4 The relative ratio of the largest grain size to the smallest specimendimension may significantly affect the numerical results. For example, smaller,cut specimens containing large grains may present different results than thebricks from which they were cut. Under no circumstances should 6” by 1” by1in. (152mm by 25mm by 25mm) specimens be prepared and tested formaterials containing grains with a maximum grain dimension exceeding 0.25 in. (6.4 mm).

3.5 This test method is useful for research and development, engineering application and design, manufacturing process control, and for developing purchasing specifications.


1” x 1” x 6”

OLD CRUSHING STRENGTH4. Apparatus4.1 Testing Machine- Any form of standard mechanical or hydraulic compression testing machine conforming to the requirements of Practices E 4 may be used.

NOTE 1- For low-strength materials (such as insulating bricks or castables), a sensitivity of 20 lbf (67 kN) or less is required. The use of a hydraulic testingmachine is also preferred over the mechanical type for these materials.

4.2 Spherical Bearing Block- The plane surface of the spherical bearing block(see Fig. 1) shall have an area which is equal to or greater than the crosssection of the test specimen.


FIG. 1 Recommended Design for Crushing Test Assembly, Including Bearing Block


5. Test Specimens5.1 Brick and Shapes (bulk density greater than 100 lb/ft3 (1.60 g/cm3)-The test specimens shall be 2 in. (51mm) cubes or cylinders, 2 in. in diameter by 2 in. (51 x 51mm) high. The height should be parallel to the originaldirection of pressing of the brick or shape. In the case of special shapes, only one specimen shall be cut from a single shape and as many of the original surfaces as possible shall be preserved. In preparing specimens from irregular or large refractory shapes, any method involving the use of abrasives, such as a high speed abrasion wheel, core drill, or rubbing bed, that will produce a specimen with approximately plane and parallel sides without weakening the structure of the specimen may be used.


2 in x 2 in x 2 in

Keywords: The height should be parallel to the original direction of pressing of the

brick or shape. In the case of special shapes, only one specimen shall be cut from a

single shape and as many of the original surfaces as possible shall be preserved. (?)


2 in x 2 in x 2 in 2 in

Ф 2 in

5.2 Insulating Brick or Shapes (typical bulk density of 100 lb/ft3 (1.60 g/cm3),or greater than 45 % total porosity, or both)- The test specimens shall be 4½by 4½ by 2½ or 3 in. (114 by 114 by 64 or 76 mm), each taken from adifferent brick. It is permissible to prepare these specimens from the half-brickresulting from the modulus of rupture test (see Sections 10-15). The selectedcompression test section shall be free of cracks, chipped surfaces, and otherobvious defects. The test surfaces shall be approximately parallel planes.

Keywords:Dimensions: 4½ x 4½ x 2½ or 3 in.


5.3 Castable Refractories- The test specimens shall be 2” x 2” x 2” (51mm x51mm x 51mm) cubes or cylinders 2 in. (51 mm) in diameter by 2 in. (51 mm)high, prepared by casting or gunning. It is permissible to prepare onespecimen from each 9” x 2” x 2”. (230mm x 51mm x 51mm) bar after themodulus of rupture test (MOR) (see Sections 10-15). The selectedcompression test section shall be free of cracks, chipped surfaces, and other obvious defects. The loaded surfaces shall be approximately parallel planes. All samples must be dried at 220 to 230°F (105 to 110°C) for 18 h (overnight). Upon removal from the oven, allow the sample to cool naturally until cool to the touch. Complete testing within 2 h of removal from the drying oven. (See Practices C 862 and C 1054.)


dried at 220 to 230°F (105 to 110°C) for 18 h (overnight).

cool naturally until cool to the touch

2 h max

TestingCured?


4.3.2 CastingRefractory cast in the mock-up shall be cured for 12 hours minimum and then stripped of forms for visual inspection only.

4.3.3 Placement of Thin Layer, Erosion Resistant Refractories Hexmesh or hexaltanchoring system (as the case may be) shall be attached to a backing plate such that the backing plate may be removed and the applied refractory lining examined from the backside. Examination of the panel may be performed immediately after ramming, or within 24 hours, as directed by the owner.

4.2.5 As directed by the contractor, test sample refractories shall be mixed and formed using metal or plastic forms at the required specimen dimensions, or larger dimensions and then cut to the required dimensions after 24-hour cure:

4.3.1 Pneumatic Gunning: The test panel shall be constructed with a removable back for visual inspection of the castable. The panel shall also be sectioned and cut surfaces inspected for voids, laminations, non-uniformities, and rebound entrapment. Sectioning or breaking of the panel is permitted 18 hours after completion of the panel unless otherwise directed by the owner.



4.3.4 Thick Layer, Plastic InstallationsAfter refractory installation is completed, the test panel backing plate shall be removed immediately and examined for consolidation and voids.


6. Procedure6.1 At least five specimens from an equivalent number of refractory shapescompose a sample.

NOTE 2- For relatively weak specimens like insulating castables or insulating firebricks, a minimum sample size of ten specimens is preferred.

6.2 Brick and Shapes- Place a cellulose fiber wall board (for example, Masonite4) 0.25 in. (6.4 mm) in thickness and extending 0.5 in. (12.7 mm) or more beyond the edges of the loaded faces of the specimen. Apply the load parallel to the direction in which the brick was originally pressed.

Comments:1 sample = 5 specimens (10 specimens for very weak materials!)


6. Procedure6.1 At least five specimens from an equivalent number of refractory shapes compose a sample.Comments:1 sample = 5 specimens (10 specimens for very weak materials!)


Minimum

7. Calculation and Report7.1 Calculate the percentage linear change based upon theoriginal length of each specimen. Report the average of the three individual values as the reheat change in the test.

ASTM C113-02 Standard Test Method for Reheat Change of Refractory Brick


specimen.

6.3 Regular and High Strength Castables- Place a cellulose fiber wall board 0.25 in. (6.4 mm) in thickness and extending 0.5 in. (12.7 mm) or morebeyond the edges of the loaded faces of the specimen. Apply the load on the2- by 2in. (51- by 51-mm) or 2in. (51-mm) diameter face and perpendicular tothe depth of the specimen as originally cast or gunned.

6.4 Insulating Brick or Shapes- Apply the load directly to the 4½- by 4½ in. (114mm x 114-mm) surface of the test specimen.

6.5 Insulating Castables (typical bulk density of 100 lb/ft3 (1.60 g/cm3), or greater than 45 % total porosity, or both)- Apply the load directly to the 2” x 2”x2”. (51mm x 5mm) face and perpendicular to the depth of the specimen as originally cast or gunned.


6.6 Use the bearing block on top of the test specimen, and position it so thatthe center of the sphere is in alignment with the vertical axis of the specimen(see Fig. 1). Keep the spherical bearing block thoroughly lubricated to ensureaccurate adjustment which may be made by hand under a small initial loadfor each specimen.

NOTE 3- The spherical bearing block may not be necessary on test machines having mechanical linkages which ensure that the stress applied is colinear with the axis of the specimen.

6.7 For dense refractories with sufficient strength to require greater than about 3 min per test, initial loading to one-half of the anticipated failure load may be accomplished at any convenient rate exceeding the specified rate. Subsequently, each specimen shall be crushed with a compressive loadapplied at the standard rates specified in Table 1. The rates shall not vary by more than ±10 % of the specified rate for the type of refractory being tested.


FIG. 1 Recommended Design for Crushing Test Assembly, Including Bearing Block


TABLE 1 Standard Loading Rates for Cold Crushing Strength

A. Where possible, loading at a constant stress rate is preferable to constant strain rate loading.

B. For dense refractory brick and shapes requiring more than a 3-min test duration, specimens may be loaded to one half of the anticipated fracture strength at any convenient rate exceeding that specified.

C. These sizes are preferred for insulating firebricks. D. These pieces may be cut from broken halves of MOR specimens. E. These sizes are preferred for insulating castables.


6.8 When using a mechanical testing machine, keep the balance beam in aconstantly floating position.

6.9 Specimens are loaded, as specified, to failure. Failure is defined as the collapse of the specimen (failure to support the load), or the reduction of the specimen height to 90 % of its original value. The maximum applied load is recorded.

Keywords:Failure is defined as:■ the collapse of the specimen (failure to support the load), or■ the reduction of the specimen height to 90 % of its original value.


7. Calculation7.1 Calculate the cold crushing strength using Eq 1:

S= W/A (1)• S = cold crushing strength, lbf/in.2 (MPa),• W = total maximum load indicated by the testing machine, lbf (N), and• A = average of the areas of the top and bottom of the specimen

perpendicular to the line of application of the load, in.2 (mm2).


8. Report8.1 Report the following:8.1.1 Designation of the materials tested (that is, manufacturer, brand,description, lot number, etc.);8.1.2 Specimen configuration, including size, shape, location in the original brick or shape, the character of the faces (that is, cut, drilled, as-pressed, as-cast, etc.), and the specimen orientation during testing;8.1.3 Pretreatment, if any, given to the test pieces (for example, curing, firing, coking, etc.);

8.1.4 Number of specimens in a sample;8.1.5 Individual specimen dimensions, the maximum applied load, and thecalculated cold crushing strength for each specimen (see 7.1);8.1.6 Mean cold crushing strength and standard deviation for each sample.


9. Precision and Bias9.1 Precision- The precision of this test method is currently being investigated.

9.2 Bias- No justifiable statement can be made on the bias of the test method for measuring the cold crushing strength of refractories, because the value of cold crushing strength can be defined only in terms of a test method.


MODULUS OF RUPTURE10. Apparatus10.1 Testing Machine- Any form of standard mechanical or hydrauliccompression testing machine conforming to the requirements of Practices E 4may be used.

NOTE 4- Properly calibrated portable apparatus may be used.



FIG. 2 Recommended Design of Bearing Cylinders for Modulus of Rupture Test

FIG. 3 Alternative Design of Bearing Cylinders for Modulus of Rupture Test


10.2 Bearing Surfaces, that shall have a radius of curvature of 5/8 in. (16 mm)or be cylindrical pieces 1¼” (32mm) in diameter. For 6” x 1” x 1”. (152mm x 25mm x 25mm) specimens, the radius of curvature shall be 3/16”. (5 mm) orcylindrical pieces 3/8”. (10mm) in diameter. All such bearing surfaces shall be straight and of a length at least equal to the width of the test specimen. The supporting members for the lower bearing surfaces shall be constructed so as to provide a means for the alignment of the bearing surfaces with the under surface of the test specimen because the test brick may have alongitudinal twist. Apparatus of the design shown in Fig. 2 is recommended, although other types may be used, provided they conform to these requirements. A satisfactory alternative design is shown in Fig. 3.


11. Test Specimens11.1 Brick and Shapes (bulk density greater than 100 lb/ft3 (1.60 g/cm3)-The preferred test specimens shall be standard 9” x 4½” x 2½” or 3”. (228mm x 114mm x 64mm or 76mm) bricks, or specimens of equivalent size ground or cut from refractory shapes. In the case of special shapes, only one specimenshall be cut from a single shape. As many original surfaces as possible shallbe preserved. Where brick sizes are impossible or impracticable, alternativespecimen sizes of 9” x 2” x 2”. (228mm x 51mm x 51mm) or 6 “ x 1” x 1”. (152mm x 25mm x 25mm) may be prepared. In preparing specimens fromirregular or larger shapes, any method involving the use of abrasives, such as a high- peed abrasion wheel or rubbing bed, that will produce a specimen with approximately plane and parallel sides without weakening the structure maybe used.


9” x 4½” x 2½” or 3”

11.2 Insulating Brick or Shapes (typical bulk density of 100 lb/ft3 (1.60 g/cm3), or total porosity greater than 45 %, or both)- The test specimens shall be whole brick measuring 9 by 4½ by 2½ or 3 in. (228mm x 114mm x 64mm or 76mm), or specimens of equivalent size cut from larger shapes.


9” x 4½” x 2½” or 3”

11.3 Castable Refractories- The test specimens shall be 9” x 2" x 2". (228 x 51mm x 51mm) bars prepared by casting or gunning. The top and bottom, and the side faces, respectively, shall be approximately parallel planes. All samples must be dried at 220°F to 230°F (105°C to 110°C) for 18 h (overnight). Upon removal from the oven, allow the sample to cool naturally until cool to the touch. Complete testing within 2 h of removal from the drying oven. (See Practices C 862 and C 1054.)


9” x 2” x 2”

dried at 220 to 230°F (105 to 110°C) for 18 h (overnight).

cool naturally until cool to the touch

2 h max

TestingCured?

12. Procedure12.1 At least five specimens from an equivalent number of refractory shapescompose a sample.

NOTE 5- For relatively weak specimens like insulating refractories, aminimum sample size of ten specimens is preferred.

12.2 Place a test specimen flat on the bearing cylinders with a span as specified in Table 2 and with the load applied at mid-span. Whenever possible, use an original, unbranded surface of a brick or shape as the tension face, that is, the face in contact with the two bottom bearing cylinders. For castable pieces, the depth dimension of the specimen as originally cast or gunned is horizontal; that is, the top surface of the casting or gunned sample becomes a side of the properly oriented test specimen.


Minimum

TABLE 2 Standard Loading Rates for Modulus of Rupture


12.3 Each specimen shall be broken at mid-span in flexure with a loadingapplied according to the standard loading rates given in Table 2. For highstrength materials requiring longer than about 3 min to perform a test, initialloading to one half of the anticipated failure load may be accomplished at anyconvenient rate exceeding the specified rate. Subsequently, the specimensshould be loaded at the standard rate specified in Table 2. The rates shall notvary more than ±10 % from the stated rate for the type of refractory beingtested. The maximum applied load is recorded.

12.4 When using a mechanical testing machine, keep the balance beam in a constantly floating position.


13. Calculation13.1 Calculate the modulus of rupture using Eq 2:

MOR = 3PL/2bd2 (2)

where:MOR = modulus of rupture, lbf/in.2 (MPa),P = maximum applied at rupture, lbf (N),L = span between supports, in. (mm),b = breadth or width of specimen, in. (mm), andd = depth of specimen, in. (mm).


b∆

∆∆

∆d

L ȼ


FIG. 2 Recommended Design of Bearing Cylinders for Modulus of Rupture Test

Ld

b

14. Report14.1 Report the following:14.1.1 Designation of the materials tested (that is, manufacturer, brand,description, lot number, etc.);

14.1.2 Specimen configuration, including size, location in the original brick or shape, the character of the faces (that is, cut, ground, as-pressed, as-cast, etc.), the specimen orientation during testing, and the load span;

14.1.3 Pretreatment, if any, given to the test pieces (for example, curing, firing, coking, etc.);

14.1.4 Number of specimens in a sample;

14.1.5 Individual specimen dimensions, the maximum applied load, thelocation of the fracture plane, and the calculated modulus of rupture for eachspecimen (see 13.1);

14.1.6 Mean modulus of rupture and standard deviation for each sample.


15. Precision and Bias15.1 Interlaboratory Test Data- An interlaboratory study was completedamong eight laboratories in 1995. Four different types of refractories weretested for cold crushing strength and cold modulus of rupture by eachlaboratory. The four types of refractories were a dense firebrick, an insulatingfirebrick, a dense castable, and an insulating castable. The dimensions of thefirebricks were 9 3 4.5 3 2.5 in., and the dimensions of the castables were 9 32 3 2 in. Before testing, bulk density and sonic velocity were measured on allrefractory bricks to ensure uniformity. Refractory bricks were then randomlyselected for distribution to the participating laboratories.


15.2 Precision- Table 3 and Table 4 contain the precision statistics for thecold crushing strength and cold modulus of rupture results, respectively.

15.2.1 Repeatability- The maximum permissible difference due to test errorbetween two test results obtained by one operator on the same material usingthe same test equipment is given by the repeatability interval (r) and therelative repeatability interval (% r). The 95 % intervals are given in Table 3and Table 4. Two test results that do not differ by more than the repeatabilityinterval will be considered to be from the same population; conversely, twotest results that do differ by more than the repeatability interval will beconsidered to be from different populations.


15.2.2 Reproducibility- The maximum permissible difference due to test errorbetween two test results obtained by two operators in different laboratories onthe same material using the same test equipment is given by thereproducibility interval (R) and the relative reproducibility interval (% R). The95 % reproducibility intervals are given in Table 3 and Table 4. Two testresults that do not differ by more than the reproducibility interval will beconsidered to be from the same population; conversely, two test results thatdo differ by more than the reproducibility interval will be considered to be fromdifferent populations.

15.3 Bias- No justifiable statement can be made on the bias of the test method for measuring the modulus of rupture of refractories because the value of the modulus of rupture can be defined only in terms of a test method.


16. Keywords16.1 crushing strength; modulus of rupture; Monolithic refractories; Refractorybrick; room temperature


TABLE 3 Precision Statistics for Cold Crushing Strength


TABLE 4 Precision Statistics for Cold Modulus of Rupture


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Reminded me of….

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Study Note 3: C181-03Standard Test Method for Workability Index of Fireclay and High-Alumina Plastic Refractories


1. Scope1.1 This test method covers the determination of the workability index offireclay and high-alumina plastic refractories by measuring the plasticdeformation of a molded test specimen when subjected to impacts.



2. Referenced Documents2.1 ASTM Standards: D 2906 Practice for Statements on Precision and Bias for Textiles


3. Significance and Use3.1 Workability index serves as a measure of the facility with which plasticrefractory materials can be rammed, gunned, or vibrated into place.

3.2 Workability index is commonly used to control consistency of plastics during manufacture. It has also been found useful for specification acceptance by the consumer.

3.3 The workability index determination can provide information for developing a plastic body. When a sample splits under impact at various water contents, it is an indication that the material is “short” or lacking in plasticity.

3.4 Determinations on samples that split during impact will be difficult to reproduce. If the sample splits, the measurement is not a true indication of deformation. This should be noted in the report.


4. Apparatus4.1 Rammer- The apparatus shall consist of the device known as the rammer for refractories3 (see Fig. 1). It shall consist essentially of a steel cylindrical mold 2.00 in. (50.8 mm) in inside diameter and 4.75 in. (120.6 mm) in length,supported in a vertical position on the same axis as a shaft to which shall be fastened a plunger that fits inside the mold. A 14-lb (6.4-kg) cylindrical weight slides on the same shaft and is arranged to fall a distance of 2 in. (51 mm) before engaging a collar fastened to the shaft.

As shown in Fig. 1, the weight may be raised by a manually rotated cam. Provision shall be made to support the weight, thereby removing the loadfrom the vertical shaft by the installation of two hooks (having a 10-32 screw thread) in the top side of the weight in a position that enables them to engage with pins (having an 8-32 screw thread) placed on each side of the upper portion of the framework, as shown in Fig. 1 and in detail in Fig. 2. A steelrule,4 one edge graduated in 0.02in. (0.5-mm) increments, shall be attached (Note 1) to the rammer so that the position of the end of the vertical shaft can be read.


FIG. 1 Apparatus for Workabilityindex Test



FIG. 2 Upper Portion of the Sand Rammer Showing Close-Up ofModifications Required

The portion of the rule to be used shall be adjusted so that when the vertical shaft is in the lowest position, its machined end is in alignment with thegraduation on the rule that represents the exact distance between the top and bottom of the bottom plate of the mold (approximately 1.7 in. (43 mm)). The upper end of the scale may be cut off flush with the top of the rod (see Note-1), which provides a rule of sufficient length for measuring the maximum distance obtainable between the ends of the mold (Note 2).


NOTE 1- One method of mounting the rule is to install in a verticalposition a 3/8”. (9.5mm) square rod, 4 1/8”. (105 mm) in length, in thatpart of the framework which constitutes the top bearing for the shaft. Oneend of the rod is reduced to a ¼”. (6.4mm) round section for a lengthof 3/8”, and this is threaded for a ¼ - 20 screw. A tapped hole, to receivethe threaded rod, is made in the framework and on the center line (fromfront to back) of the apparatus. When tightening the rod in place, one facemust be in a position so that the rule can be sweat-soldered to it as shownin Fig. 2.

NOTE 2- The apparatus as described in this section is capable ofmeasuring workabilities up to about 32%. For products of higherworkability a suitable spacer block5 may be installed under the specimen.


4.1.1 Mounting for Rammer- The rammer shall be mounted on a 27in. (686-m) high concrete column, having a base measuring at least 8 by 11 in. (200 x279 mm). Four ¼”. (6.4mm) bolts, at least 3 in. (76mm) in length, shall becast in the top of the column and shall be grouted with a suitable mortar.Variable results are obtained from the test unless the described mounting oran acceptable alternative mounting6 is used for the rammer.

4.1.2 Maintenance and Calibration- As needed, depending on use, clean allmoving parts and lubricate with SAE 10 oil. Make periodic checks of theheight that the weight drops to insure the weight is being raised 2 in. (51mm).Inspect the rammer to determine whether it and the foundation are producingfull ramming energy. This is accomplished by using calibrated impact rings.7

NOTE 3- Variation in the smoothness and dimensions of the specimen tubemay cause variation in workability values. For referee testing the specimentube may require periodic comparison with a master precision specimentube.8


5. Test Specimens5.1 Temperature of Plastic Refractory- Since the workability index may varywith a wide spread of temperature, the temperature of the material to betested must be between 65°F and 75°F (18°C and 24°C) to reduce this variable. Record temperature of material before forming the cylinder.

NOTE 4- As much as a 3-point change in the workability index may occur within the 10°F (6°C) stated range.

5.2 Number of Specimens- Five cylindrical test specimens shall be molded from the sample (Note ) of plastic refractory.


5.3 Molding of Specimens- The interior of the mold shall be cleaned and coated with a light film of suitable parting agent9 prior to the preparation of each specimen. To facilitate filling the mold, the sample shall be broken into pieces varying in size, the largest dimension being about 1 in. (25 mm). The sample weight shall be chosen to provide a sample height of 2.5 ±0.1 in. (64 ±3 mm). For a super-duty plastic, the sample weight is approximately 300g; for an 85 to 90 % alumina plastic, approximately 375g. After placing the material in the mold, it shall be subjected to ten impacts by turning the handle, which causes the weight to be raised 2 in. (51 mm) and then dropped upon the collar attached to the plunger shaft. The mold containing the sample shall then be upended and an additional ten impacts given to the specimen. The formed test specimen shall then be extruded from the mold by the use of a suitable auxiliary plunger.


6. Procedure6.1 Remove the load on the plunger of the mold by suspending the weightfrom the framework. Do this by slightly rotating the weight while engaging thehooks on the pins in the framework. After raising the vertical shaft, place thetest specimen on the bottom of the mold and lower the shaft until the plungeris in firm contact with the specimen. Obtain the length of the specimen to thenearest 0.02 in. (0.5 mm) by sighting on the rule and the end of the shaft.Disengage the weight from its support and carefully lower it until it is at rest inits normal position. Then apply three impacts from the weight to the testspecimen. Read the final length of the specimen from the scale, and recordthe difference in inches or millimetres between the two measurements.


7. Calculation and Report7.1 Calculate the percentage deformation for each of the five test specimenson the basis of the original length and report the average value as theworkability index. The workability index shall be calculated by the followingequation, and shall be rounded off to one decimal place.

whereL = length of specimen prior to deformation,L1 = length of specimen after deformation, andW = workability index.

7.2 State the temperature of the sample, the specimen weight used, and whether any test specimen crumbled as a result of the three impacts.


8. Precision and Bias8.1 Interlaboratory Test Data10- An interlaboratory test was run in 1975, inwhich two laboratories each tested ten specimens from each of two plasticmaterials: a super-duty and a high-alumina phosphate-bonded plastic.Samples were selected from the same container of plastic and tested in eachlaboratory at the same time. The components of variance for workability indexresults calculated by the procedures given in Practice D 2906 are as follows:Within-laboratory component 4.1% of the average Between-laboratorycomponent 5.1% of the average

8.2 Precision- For the components of variance given in 8.1, two averages of test values should be considered significantly different at the 95 % probability level if the difference equals or exceeds the critical difference listed as follows (for t = 1.96):


8.3 Bias- No justifiable statement on bias is possible since the true value ofthe workability index cannot be established by an accepted reference material.


9. Keywords9.1 refractories; refractory plastic; workability


Foot Notes1. This test method is under the jurisdiction of ASTM Committee C08 on

Refractories and is the direct responsibility of Subcommittee C08.09 onMonolithic Refractories. Current edition approved November 1, 2003.Published January 2004. Originally approved in 1943. Last previous edition approved in 1997 as C 181-91 (1997) e 1.

2. For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [email protected]. For Annual Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website.


3 The rammer for refractories, Model 315-R, is available from Dietert FoundryTesting Equipment, 9190 Roselawn Ave, Detroit, MI 48204. Accessory partsrequired for conduct of this test and calibration of the rammer include:

Test Equipment Part NumberSpecimen tube 315-9Cup pedestal 315-111.000 in. cup pedestal spacer block 3 15R-8Stripping post 315-14Specimen tube conditioner 315-30Replacement swab for 315-30 315-02006Liquid parting pattern spray 315-02007

Calibration Equipment Part NumberRammer foundation tester 307(includes impact rings, micrometer, and test anvil)Replacement impact rings 307-3AMaster precision specimen tube 315-18


4. A suitable rule is the Lufkin Rule Co. Rule No. 2103-R, which is 6 in. (152mm) in length and must be cut off at each end so that the desired portion of the graduations aligns with the shaft.

5. A suitable 1in. (25-mm) spacer block is listed in footnote 4. 6. An acceptable alternative mounting is available from Dietert Foundry

Testing Equipment; use the rammer base, part no. 315-27, and the rammer pedestal, part no. 315-45.


7. Part number 307 as provided by Dietert Foundry Testing Equipment, consists of a set of precision steel rings, a steel anvil and a micrometer, has been found suitable for this purpose. To determine full ramming energy, the anvil is positioned in the specimen tube locating hole in the base of the rammer. A test ring is then placed in the center of the anvil with the axis of the ring being horizontal. The ring is then subjected to 3 impacts of the rammer head. A measurement across the center of the deformed ring is then made and compared to the limits specified on the box containing the rings. Detailed instructions are included in the calibration kit.

8. Part number 315-18 as provided by Dietert Foundry Testing Equipment, has been found suitable for this purpose.

9. A suitable parting agent is provided by Dietert Foundry Testing Equipment, as described in footnote 4.

10. Supporting data are available from ASTM International Headquarters. Request RR: C 08 – 1003.


Study Note 4: C704-01Standard Test Method for Abrasion Resistance of Refractory Materials at Room Temperature


1. Scope1.1 This test method covers the determination of relative abrasion resistanceof 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 plastic refractories (see Practice C1054).

1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only.



2. Referenced Documents2.1 ASTM Standards:• C 134 Test Methods for Size, Dimensional Measurements, and Bulk

Density of Refractory Brick and Insulating Firebrick • C 179 Test Method for Drying and Firing Linear Change of Refractory

Plastic and Ramming Mix Specimens • C 861 Practice for Determining Metric Dimensions of Standard Series

Refractory Brick and Shapes • C 862 Practice for Preparing Refractory Concrete Specimens by Casting • C 865 Practice for Firing Refractory Concrete Specimens • C 1054 Practice for Pressing and Drying Refractory Plastic and Ramming

Mix Specimens


3. Summary of Test Method3.1 This test method measures the volume of material in cubic centimetresabraded from a flat surface at a right angle to a nozzle through which 1000 gof size-graded silicon carbide grain is blasted by air at 448 kPa (65 psi).


4. Significance and Use4.1 This test method measures the relative abrasion resistance of various refractory samples under standard conditions at room temperature.

4.2 The abrasion resistance of a refractory material provides an indication of its suitability for service in abrasion or erosive environments.

4.3 The results obtained by this test method could be different than thoseobtained in service because of the different conditions encountered.


5. Apparatus5.1 Abrasion Tester, used for measuring the abrasion resistance of refractoryspecimens, consisting of the following (Fig. 1 and Fig. 2):

5.1.1 Blast Gun, modified for this equipment as shown in Fig. 3.

5.1.2 Nozzle- A piece of glass tubing is used to replace the steel nozzle supplied with the sand-blast gun to permit control of nozzle size through nozzle replacement after each determination. Flint-glass tubing, 115 mm (4½“) long, 7 mm (¼”) in outside diameter, with a nominal 1.1 mm (1/16”) wall, isused. This piece of glass tubing is held in place by a 70 mm (2¾”) long piece of stainless steel tubing. The I.D. (inside diameter) of this tubing, which should be flared at one end to sit snugly inside a 9.53 mm (3/8in.) tubing nut, should be 7.15 mm (9/32”). The O.D. (outside diameter) should be 9.53 mm(3/8”).


NOTE 1- Identified by number in this figure are: (1) cabinet pressure manometer, (2) dust collector vent, (3) test pressure gage, (4) grit feed tunnel,and (5) vacuum gage. FIG. 1 Abrasion Tester


FIG. 1 Abrasion Tester

Charlie C

hong/ Fion Zhang

NOTE 1- Identified by number in this figure are: (1) sand blast gun, (2) air pressure regulator, (3) glass tube and metal stabilizing sleeve, (4) test sample,and (5) adjustable platform. FIG. 2 Abrasion Tester


FIG. 2 Abrasion Tester

Charlie C

hong/ Fion Zhang

NOTE 1- Identified 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 Breakdown


FIG. 3 Modified Blast Gun Breakdown


This sleeve is glued in place along with a rubber grommet of proper size, inside the 9.53 mm (3/8”) tubing nut, and is used primarily to hold the glass tubing perpendicular to the test sample, assuring a proper vacuum within the gun. The end of the glass tube, through which the abrading media enters thenozzle in the venturi chamber, is placed at a distance of 2 mm (0.08”) fromthe air-generator nozzle. This is done by placing the glass tubing on a brassrod, 4.5 mm (0.175”) in diameter with a shoulder 7.9 mm (5/16 in.) in diameter, 117 mm (4.68”) from the tip. This will allow the operator to push the glass tubing up through the rubber grommet until the rod touches the nozzle, assuring a 2 mm(0.08”) gap between the nozzle and the glass tubing.


5.1.3 Venturi- The air-generator nozzle should have an inlet inside diameterof from 2.84 to 2.92 mm (0.112 to 0.115 in.) and an outlet inside diameter offrom 2.36 to 2.44 mm (0.093 to 0.096 in.). The surface of the air-generatornozzle within the venturi chamber of the gun is protected from the abradingmedia with a 9.4 mm (3/8 in.) long piece of vinyl tubing 4.7 mm (3/16 in.)inside diameter with a 1.5 mm (1/16 in.) wall thickness. The inside diameter of the venturi chamber should not exceed 10 mm (3⁄8 in.) and should bechecked periodically for wear.

5.1.4 Air Supply- The air line pressure shall be maintained at the desired pressure at the gun through the use of a standard suppressed range air gage indicating 6.9 kPa (61 psi) mounted as close to the gun as possible. Only clean dry air should be used.


5.1.5 Abrading Media- No. 36 grit silicon carbide having a screen analysis asshown in Table 1.

5.1.6 Feeding Mechanism- Two acceptable mechanisms for feeding the abrading media are shown in Fig. 4. The feed funnel must contain a suitable orifice to obtain a flow time of 450±15 s while delivering 1000 g of abrading media into the gun supply funnel. Metal, glass, or plastic orifices can be usedto regulate the flow. There must be an air gap between the orifice and the gun supply funnel to allow secondary air to enter with the abrading media.

5.1.7 Test Chamber, consisting of a tightly sealed closure with a door to permit ready access for mounting and removing the test specimens. A 13mm ( ½“) hole shall be cut in the top of the test chamber to permit the vertical mounting of the blast gun such that the downward stream of abrading media will travel 203mm (8 in.) from the glass nozzle tip to the test specimen. Fig. 1 and Fig. 2 show the design of an acceptable chamber.


TABLE 1 Screen Analysis for Abrading Media


NOTE 1- Identified 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 Mechanisms


FIG. 4 Feeding Mechanisms

Charlie C

hong/ Fion Zhang

5.1.7.1 Dust Collector- A standard dust-collecting cloth bag of adequatecapacity may be used on the 52 mm (2 1/16 in.) exhaust port of the chamber.This port is equipped with a butterfly valve to regulate the pressure in thechamber during the test. Alternate dust handling systems are acceptable aslong as the chamber pressure is maintained at the desired level.

5.1.7.2 Manometer- During the test the chamber pressure shall be measured with a water manometer having a scale such that 311 Pa (1¼ in.) of water may be readily measured. A 6 mm (¼ in.) inside diameter pet cock shall be mounted in the top of the chamber to permit manometer connection.

5.2 Balance, capable of weighing the sample to an accuracy of ±0.1 g, used for weighing the abrading media and test specimens. Typically a 2000 g to 3000 g capacity balance is required.


6. Test Specimens6.1 Test specimens shall be cut from refractory brick or shapes, or moldedfrom monolithic refractory materials and measure from 100 by 100 by 25 mm(4 by 4 by 1 in.) to 114 by 114 by 65 or 76 mm (4½ by 4 ½ by 2½ or 3 in.).Only the most abrasion resistant materials can be 25 mm (1 in.) thick sincethe test is invalid if a hole is eroded completely through the specimen.

6.2 Castable refractories shall be molded in accordance with Practice C 862 and fired to anticipated service temperatures in accordance with Practice C 865.

6.3 Plastic refractories shall be molded and fired to anticipated servicetemperature in accordance with Test Method C 179 (see the sections onapparatus and test specimens).


7. Procedure7.1 Dry the test specimens to a constant weight at 105°C to 110°C (220 to 230°F) before testing.

7.2 Weigh the specimens to the nearest 0.1 g. Determine the volume of the specimens by measurement of length, width, and thickness to the nearest 0.5 mm (1⁄50 in.) in accordance with the apparatus section of Test Methods C 134.

7.3 Place the nominal 114mm by 114 mm (4½ by 4 ½ in.) face of the test specimens at a 90° angle to the glass nozzle with the unbranded surface to be abraded 203 mm (8 in.) from the tip of the glass nozzle. With monolithic refractory specimens, the surface (that is, top troweled face or bottom mold face) that most accurately reflects the actual field situation should be the test surface.


7.4 Turn on the air pressure and regulate it to 448 kPa (65 psi). Check the airpressure before and after the abrading media is run through the system.

7.5 Measure the cabinet pressure using the water manometer and maintain the pressure in the chamber at 311 Pa (1¼ in.) of water by means of thebutterfly valve in the exhaust vent.

7.6 After the air pressure to the gun and the chamber pressure have been adjusted, disconnect the media line to the gun and place a 30 in. of mercury vacuum gauge in position. If the vacuum gauge does not show a minimum of 15 in. Of mercury, check the position of the glass tubing or the condition of the air-generator nozzle. After obtaining the proper vacuum pressure, reconnect the feed tube and recheck the cabinet pressure before placing 1000 ± 5 g of dry abrading media in the reserve funnel. The feed funnel to the gun must not fill completely or flood with material. The feed mechanism when connected with the test apparatus must deliver the abrading media in the specified time of 450 ± 15 s.


7.7 Use the silicon carbide abrading media no more than 5 times beforediscarding. Remove the material retained on No. 20 (850μm) and passing No.50 (300μm) sieves after each run.

7.8 Remove the refractory specimens from 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 density of the specimensin grams per cubic centimetre.

8.2 Calculate the amount of refractory lost by each specimen by abrasion in cubic centimetres, A, as follows:

A = (M1 - M2)/B = M/B

Where:A = volume of refractory lost cm3

B = bulk density, grams per cubic centimetre (g/cm3),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 the abrasion loss for that sample.

8.4 Record and report the time required for 1000 g of abrading media to flowthrough the gun.

8.5 Report which surface was abraded.


9. Precision and Bias9.1 Interlaboratory Test Data- An interlaboratory study was completedamong eight laboratories in 1999. Five different types of refractories, alongwith a plate glass standard, were tested for abrasion resistance by eachlaboratory. The five types of refractories were a high-alumina brick, a silicabrick, an abrasion-resistant castable, a super-duty fire brick, and aconventional high-cement castable. All specimens were 4.5 by 4.5 in. in crosssection. Additionally, both castables were fired to 1500°C. Prior to testing,bulk density and sonic velocity were measured on all specimens to ensureuniformity. Specimens were then randomly selected for distribution to theparticipating laboratories.


9.2 Precision- Table 2 contains the precision statistics for the abrasionresistance results.

9.2.1 Repeatability- The maximum permissible difference due to test error between two test results obtained by one operator on the same material using the same test equipment is given by the repeatability interval (r) and the relative repeatability interval (%r). The 95 % repeatability intervals are givenin Table 2. Two test results that do not differ by more than the repeatability interval will be considered to be from the same population; conversely, two test results that do differ by more than the repeatability interval will be considered to be from different populations.


9.2.2 Reproducibility- The maximum permissible difference due to test errorbetween two test results obtained by two operators in different laboratories onthe same material using the same test equipment is given by thereproducibility interval (R) and the relative reproducibility interval (%R). The95 % reproducibility intervals are given in Table 2. Two test results that do notdiffer by more than the reproducibility interval will be considered to be fromthe same population; conversely, two test results that do differ by more thanthe reproducibility interval will be considered to be from different populations.

9.3 Bias- No justifiable statement can be made on the bias of the test method for measuring the abrasion resistance of refractories because the value of the volume loss can be defined only in terms of a test method.


TABLE 2 Precision Statistics for Abrasion Resistance


10. Keywords10.1 abrasion resistance; blasted by air; castable refractories; flat surface;monolithic refractory materials; Refractory brick or shape; room temperature



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