ASTM C1656-13(2018)

Standard Guide for Measuring the Reactivity of Hydraulic Refractory Castables Using Exothermic Profile

SIGNIFICANCE AND USE
4.1 The heat of hydration of a calcium aluminate-based castable is liberated over a short period of time (as compared to portland cement). This makes it easy to measure the heat profile using off-the-shelf thermocouple equipment.  
4.2 The heat profile can be used to make inferences about the setting and strength gain behavior of a castable and sometimes the working time of a castable.  
4.3 Factors that should be controlled when comparing two castables include: size, shape, and mass of cast object, start temperature of the mix, temperature of environment, and the thermal conductivity of the environment. If these factors are held constant, then the two castables’ heat profiles can be compared.  
4.4 The temperature increase created by the castable exothermic reaction shall be at least 2.0 °C more than the normal fluctuation of the laboratory temperature so that the time of this increase is easily discernible to the user.  
4.5 Varying the amount of cement in the castable, the amount of water, the type and quantity of admixtures, and so forth, will change the shape, maximum temperature, and time to maximum temperature of the curve.  
4.6 Following is an example of a curve generated for an LCC (see Fig. 1) that does exhibit two peaks, the first one marking the end of working time. In this curve, one could also infer that the start temperature of the mix was 24 °C and also that the hydraulic strength gain reaction was significantly started, but not completed by 6 h.
FIG. 1 Example of LCC Exo Profile
SCOPE
1.1 This guide applies to all castables with a reactive binder system that produces a measurable heat profile during the setting and hardening process. The majority of these systems will have calcium aluminate cement as one component of the binder system.  
1.2 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Historical
• Publication Date: 30-Sep-2018
• ICS: 91.100.10 - Cement. Gypsum. Lime. Mortar
• Technical Committee: C08 - Refractories
• Drafting Committee: C08.09 - Monolithics

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: C1656 − 13 (Reapproved 2018)
Standard Guide for
Measuring the Reactivity of Hydraulic Refractory Castables
Using Exothermic Profile
This standard is issued under the fixed designation C1656; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 4. Significance and Use
1.1 This guide applies to all castables with a reactive binder 4.1 The heat of hydration of a calcium aluminate-based
system that produces a measurable heat profile during the
castable is liberated over a short period of time (as compared
setting and hardening process. The majority of these systems to portland cement). This makes it easy to measure the heat
will have calcium aluminate cement as one component of the
profile using off-the-shelf thermocouple equipment.
binder system.
4.2 The heat profile can be used to make inferences about
1.2 This standard does not purport to address all of the
the setting and strength gain behavior of a castable and
safety concerns, if any, associated with its use. It is the
sometimes the working time of a castable.
responsibility of the user of this standard to establish appro-
4.3 Factors that should be controlled when comparing two
priate safety, health, and environmental practices and deter-
castables include: size, shape, and mass of cast object, start
mine the applicability of regulatory limitations prior to use.
temperature of the mix, temperature of environment, and the
1.3 This international standard was developed in accor-
thermal conductivity of the environment. If these factors are
dance with internationally recognized principles on standard-
held constant, then the two castables’ heat profiles can be
ization established in the Decision on Principles for the
compared.
Development of International Standards, Guides and Recom-
4.4 The temperature increase created by the castable exo-
mendations issued by the World Trade Organization Technical
thermic reaction shall be at least 2.0 °C more than the normal
Barriers to Trade (TBT) Committee.
fluctuation of the laboratory temperature so that the time of this
increase is easily discernible to the user.
2. Referenced Documents
2.1 ASTM Standards: 4.5 Varying the amount of cement in the castable, the
C71 Terminology Relating to Refractories amount of water, the type and quantity of admixtures, and so
C401 Classification of Alumina and Alumina-Silicate forth, will change the shape, maximum temperature, and time
Castable Refractories to maximum temperature of the curve.
C862 Practice for Preparing Refractory Concrete Specimens
4.6 Following is an example of a curve generated for an
by Casting
LCC (see Fig. 1) that does exhibit two peaks, the first one
marking the end of working time. In this curve, one could also
3. Terminology
infer that the start temperature of the mix was 24 °C and also
3.1 Definitions:
that the hydraulic strength gain reaction was significantly
3.1.1 EP – exothermic profile, n—the curve generated by
started, but not completed by 6 h.
plotting temperature of the embedded thermocouple versus
time.
5. Apparatus
3.1.2 LCC, n—low-cement castable.
5.1 Mixing equipment as prescribed in Practice C862.
5.2 Type T thermocouple. (Type J, E, or K is also acceptable
but not preferred due to range of sensitivity. Other types cannot
This guide is under the jurisdiction of ASTM Committee C08 on Refractories
be used.) Wire ends should be joined by solder or welding.
and is the direct responsibility of Subcommittee C08.09 on Monolithics.
Simple twisting is not recommended due to the potential for
Current edition approved Oct. 1, 2018. Published October 2018. Originally
approved in 2007. Last previous edition approved in 2013 as C1656 – 13. DOI:
inaccurate readings.
10.1520/C1656-13R18.
5.3 Thermocouple sheathing (optional).
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
5.4 Vo
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C1656 − 13 C1656 − 13 (Reapproved 2018)
Standard Guide for
Measuring the Reactivity of Hydraulic Refractory Castables
usingUsing Exothermic Profile
This standard is issued under the fixed designation C1656; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This guide applies to all castables with a reactive binder system that produces a measurable heat profile during the setting
and hardening process. The majority of these systems will have calcium aluminate cement as one component of the binder system.
1.2 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.3 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
C71 Terminology Relating to Refractories
C401 Classification of Alumina and Alumina-Silicate Castable Refractories
C71 Terminology Relating to Refractories
C862 Practice for Preparing Refractory Concrete Specimens by Casting
3. Terminology
3.1 Definitions:
3.1.1 EP – exothermic profile, n—the curve generated by plotting temperature of the embedded thermocouple versus time.
3.1.2 LCC, n—Low cement low-cement castable.
4. Significance and Use
4.1 The heat of hydration of a calcium aluminate based aluminate-based castable is liberated over a short period of time (as
compared to Portlandportland cement). This makes it easy to measure the heat profile using off-the-shelf thermocouple equipment.
4.2 The heat profile can be used to make inferences about the setting and strength gain behavior of a castable and sometimes
the working time of a castable.
4.3 Factors that should be controlled when comparing two castables include: size, shape, and mass of cast object, start
temperature of the mix, temperature of environment, and the thermal conductivity of the environment. If these factors are held
constant, then the two castablescastables’ heat profiles can be compared.
4.4 The temperature increase created by the castable exothermic reaction shall be at least 2.0°C2.0 °C more than the normal
fluctuation of the laboratory temperature so that the time of this increase is easily discernible to the user.
4.5 Varying the amount of cement in the castable, the amount of water, the type and quantity of admixtures, and so forth, will
change the shape, maximum temperature, and time to maximum temperature of the curve.
This guide is under the jurisdiction of ASTM Committee C08 on Refractories and is the direct responsibility of Subcommittee C08.09 on Monolithics.
Current edition approved April 1, 2013Oct. 1, 2018. Published June 2013October 2018. Originally approved in 2007. Last previous edition approved in 20072013 as C1656
– 07.13. DOI: 10.1520/C1656-13.10.1520/C1656-13R18.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1656 − 13 (2018)
4.6 Following is an example of a curve generated for an LCC (see Fig. 1) that does exhibit two peaks, the first one marking
the end of working time. In this curve, one could also infer that the start temperature of the mix was 2
...