ASTM_C_1100_-_88_1998.pdf

Designation:C 1100 88(Reapproved 1998)Standard Test Method forRibbon Thermal Shock Testing of Refractory Materials1This standard is issued under the fixed designation C 1100;the number immediately following the designation indicates 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 This test method covers the procedure for determiningthe relative resistance of fired fireclay and high aluminarefractories to thermal shock conditions resulting from speci-fied heating and cooling cycles.The equipment specified isbased on test units currently in use at several industriallaboratories.1.2 The values stated in inch-pound units are to be regardedas the standard.The values given in parentheses are providedfor information purposes 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 regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:C 885 Test Method for Youngs Modulus of RefractoryShapes by Sonic Resistance23.Significance and Use3.1 The measurement or assessment of thermal shock dam-age of refractory materials is an important consideration inrefractory selection for process vessels and furnaces.3.2 This test method allows for a quantitative assessment ofthermal shock damage based on either destructive or nonde-structive test methods,or both.4.Apparatus4.1 Burner FrameSheet metal and angle iron providesupport for the line burner,protective liner brick,and testsamples.A cross section view of the unit is shown in Fig.1.The unit is approximately 15 in.(0.38 m)wide,69 in.(1.75 m)long,and 25 in.(0.64 m)high.Provision should be made toeasily adjust the vertical burner-to-sample(hot face)distance,if needed.Wheels can be attached to the frame to permit easyrelocation of the unit.Fig.2 shows the material and dimensiondetails needed for constructing the burner frame.4.2 BurnerA segmented line burner(gas),with five 12 in.(0.305 m)connected sections is suggested.Burners of 300 000to 900 000 BTU/h capacity are in use.Both center and end-fedburners are in use.Consideration should be given to theend-to-end temperature variation and control(610F(65.5C)of whichever burner system is used.A typicalburner system is shown in Fig.3.An ignition device is neededto initiate firing for each of the heating cycles.A safety deviceis needed to shut off the gas in case of flame-out or otherunexpected shutdown.4.3 Temperature MeasurementSample hot face tempera-ture should be measured at the center and each end of thesample setting.The capability is needed to insert a protected(alumina(Al2O3)tube)thermocouple horizontally through theframe into a cut hot face slot in dummy brick positioned acrossthe burner at each of the desired measurement sites.3Thethermocouple bead should be positioned in the center(hottestzone)of the flame,within the groove in the dummy brick.During testing,a sharply defined flame should actually contactthe hot face surface of the test brick(original face)creating a“red hot central band approximately 2 in.(50 mm)wide.Coldface thermocouples can be used if desired,to monitor thetemperature gradient.An appropriate temperature-measuringor recording device,or both,should be attached to properlymonitor the test conditions.4.4 Gas/Air Flow SystemThe basic components for gas/air flow control,with the line burner,are shown in Fig.3.Valves are needed to turn gas on and off at specified timesduring the cyclic operation.A gas regulator is used to maintainuniform flow.Blowers of from 75 to 150 ft3/min(2.1 to 4.2m3/min)capacity are in use.The blower operates continuously1This test method is under the jurisdiction of ASTM Committee C-8 onRefractories and is the direct responsibility of Subcommittee C08.02 on ThermalStress Resistance.Current edition approved July 29,1988.Published September 1988.2Annual Book of ASTM Standards,Vol 15.01.3Barna,G.,“Ruggedness Evaluation of the Ribbon Test,Report to ASTMSubcommittee C08.02(based on RRC test data),March 1982.FIG.1 Diagram Showing a Cross Section View of the BasicComponents of the Ribbon Test Furnace1Copyright ASTM,100 Barr Harbor Drive,West Conshohocken,PA 19428-2959,United States.during the heating and cooling cycles of the test.If desired,automated cycling operation of this test can be provided.4.5 SampleEvaluationEquipmentDegradationofsamples,due to thermal shock exposure can be quantified bymeasured property changes(before and after test).The pre-ferred,most statistically valid evaluation procedure3involvesmeasurement of modulus of elasticity,in accordance with TestMethod C 885(sonic resonance technique).An alternativeprocedure,described in the literature4,using ultrasonic velocitymea