1、Designation: C 1656 07Standard Guide forMeasuring the Reactivity of Hydraulic Refractory Castablesusing Exothermic Profile1This standard is issued under the fixed designation C 1656; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、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 guide applies to all castables with a reactive bindersystem that produces a measurable heat profile
3、during thesetting and hardening process. The majority of these systemswill have calcium aluminate cement as one component of thebinder system.1.2 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
4、 to establish appro-priate safety and health practices and to determine theapplicability of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 401 Classification of Alumina and Alumina-SilicateCastable RefractoriesC 71 Terminology Relating to RefractoriesC 862 Practice
5、for Preparing Refractory Concrete Speci-mens by Casting3. Terminology3.1 Definitions:3.1.1 EP exothermic profile, n the curve generated byplotting temperature of the embedded thermocouple versustime.3.1.2 LCC, nLow cement castable4. Significance and Use4.1 The heat of hydration of a calcium aluminat
6、e basedcastable is liberated over a short period of time (as comparedto Portland cement). This makes it easy to measure the heatprofile using off-the-shelf thermocouple equipment.4.2 The heat profile can be used to make inferences aboutthe setting and strength gain behavior of a castable andsometime
7、s the working time of a castable.4.3 Factors that should be controlled when comparing twocastables include: size, shape and mass of cast object, starttemperature of the mix, temperature of environment, and thethermal conductivity of the environment. If these factors areheld constant, then the two ca
8、stables heat profiles can becompared.4.4 The amount of heat rise created by the castable shall bea minimum of 5F. If this is not achieved, then either a largersample or better insulation (or both) should be used to increasethe measurable heat release.4.5 Varying the amount of cement in the castable,
9、 theamount of water, the type and quantity of admixtures, and soforth, will change the shape, maximum temperature and time tomaximum temperature of the curve.4.6 Following is an example of a curve generated for anLCC (see Fig. 1) that does exhibit two peaks, the first onemarking the end of working t
10、ime. In this curve one could alsoinfer that the start temperature of the mix was 24C and alsothat the hydraulic strength gain reaction was significantlystarted, but not completed by 6 h.5. Apparatus5.1 Mixing equipment as prescribed in C 862.5.2 Type T thermocouple (Type J, E, or K are also accept-a
11、ble but not preferred due to range of sensitivity. Other typescannot be used.) Wire ends should be joined by solder orwelding. Simple twisting is not recommended due to thepotential for inaccurate readings.5.3 Thermocouple sheathing (optional)5.4 Voltmeter, data acquisition card or some other instru
12、-ment to read the thermocouple mV value.5.5 Container for storage of castable during heat profilegeneration and constant temperature environment in which tostore the container.5.6 Personal computer loaded with above card will makecurve generation easier.6. Hazards6.1 There are no known hazards assoc
13、iated with the method.Safe practice should be used when mixing the castable.Castable MSDS should be consulted to determine if anyhazards exist with the castable.1This guide is under the jurisdiction of ASTM Committee C08 on Refractoriesand is the direct responsibility of Subcommittee C08.09 on Monol
14、ithics.Current edition approved March 1, 2007. Published April 2007.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM w
15、ebsite.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7. Procedure7.1 Prepare the castable according to the manufacturersmixing instructions noting the time of water addition. Forcomparison testing, the water addition should produce
16、 acomparable consistency of the castables.7.2 If the entire sample will not be used for the EPgeneration, grab select a representative sample of required sizefrom the mixing bowl by successive quartering when the mixeris turned off.7.3 Place castable in a container. Place container in anenvironment
17、with constant temperature.7.4 Place thermocouple in the center of the castable in thecontainer. Use of a sheath is not required but will allow foreasier removal of the thermocouple later. Use of an insulatingcontainer will drive the final peak temperature to a higherpoint.7.5 Begin taking readings w
18、ithin 5 minutes of placing thecastable in the container. Readings can be taken either manu-ally at desired time intervals (note the mV (or temperature)reading readjusting your time 0 from the water addition pointor automatically with a PC) by using a strip recorder orautomatically gathering the info
19、rmation with a PC outfittedwith the correct hardware to read thermocouple values.7.6 Plot temperature versus time to view the EP. This can beautomated through the use of a personal computer and a dataacquisition card or a strip or chart recorder.8. Report8.1 Record the type of castable, mixing time,
20、 and wateradded and consistency after mixing.8.2 Record the temperature of the immediate surroundings.8.3 Record the amount of castable and the type of containerused during the EP generation.8.4 Record the type and presence of any insulation used asthe container or around the container.8.5 Record th
21、e start temperature.8.6 Generate the EP curve.9. Keywords9.1 castable; refractory; exothermic profile; EP; workingtimeASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly
22、 advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, ei
23、ther reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may atten
24、d. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).FIG. 1 Example of LCC Exo ProfileC1656072
