ASTM C210-95(2024)

Standard Test Method for Reheat Change of Insulating Firebrick

SIGNIFICANCE AND USE
3.1 Insulating firebrick (IFB) are classified by their bulk density and reheat change (see Classification C155). This test method defines thermal stability by measurement of IFB's reheat change following 24 h at a test temperature.  
3.2 Since this test exposes the entire sample to an isothermal temperature condition, the user should be aware that most applications for IFB involve a thermal gradient which may cause the IFB's dimensions to change differentially.
SCOPE
1.1 This test method covers the determination of the permanent linear (and volume) change of insulating firebrick upon reheating 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.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 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: Published
• Publication Date: 31-Mar-2024
• ICS: 81.080 - Refractories
• Technical Committee: C08 - Refractories
• Drafting Committee: C08.03 - Physical Properties

Relations

• Replaces: ASTM C210-95(2019) - Standard Test Method for Reheat Change of Insulating Firebrick
• Effective Date: 01-Apr-2024
• Referred By: ASTM C356-22 - Standard Test Method for Linear Shrinkage of Preformed High-Temperature Thermal Insulation Subjected to Soaking Heat
• Effective Date: 01-Apr-2024
• Referred By: ASTM C113-14(2019) - Standard Test Method for Reheat Change of Refractory Brick
• Effective Date: 01-Apr-2024
• Referred By: ASTM F1312-19(2023) - Standard Specification for Brick, Insulating, High Temperature, Fire Clay
• Effective Date: 01-Apr-2024
• Referred By: ASTM C155-97(2022) - Standard Classification of Insulating Firebrick
• Effective Date: 01-Apr-2024

Overview

ASTM C210-95(2024), Standard Test Method for Reheat Change of Insulating Firebrick, defines a comprehensive procedure for determining the permanent linear and volume change of insulating firebrick (IFB) upon reheating under specified conditions. Developed by ASTM International, this standard is integral to evaluating the thermal stability of insulating firebrick commonly used in high-temperature industrial applications. The method measures the permanent dimensional changes-commonly known as reheat change-following 24 hours at a controlled test temperature. This provides vital information about the long-term reliability and performance of IFB products under exposure to high temperatures.

Key Topics

• Thermal Stability Assessment: The test measures changes in the dimensions and volume of insulating firebrick after a controlled reheating cycle, simulating real-world thermal exposure.
• Classification by Properties: IFBs are classified by bulk density and reheat change, aligning with ASTM C155 for Insulating Firebrick Classification.
• Standardized Test Conditions: The method prescribes specific test temperatures determined by the classification group of the IFB, precise kiln operating parameters, and a 24-hour isothermal hold period.
• Measurement Procedures: Outlines rigorous specimen preparation, measurement points, and accuracy requirements to ensure reproducibility and comparability across laboratories.
• Reporting and Calculation: Provides formulas for calculating both reheat linear change and reheat volume change, with specific instructions for consistent reporting.

Applications

This ASTM standard is widely used across industries that rely on high-temperature insulation and fire-resistant materials, such as:

• Refractories Manufacturing: To ensure product quality, consistency, and compliance with industry standards for insulating firebrick.
• Industrial Furnace Construction and Maintenance: Assists engineers and technicians in selecting IFBs with proven thermal stability for installation in furnaces, kilns, and other high-heat environments.
• Quality Assurance and Research Laboratories: Facilitates repeatable, comparable testing for new products, manufacturing quality control, and material performance analysis.
• Procurement and Specification: Used by specifiers and procurement professionals to verify supplier compliance and performance of insulating refractories according to recognized international standards.
• Safety and Reliability Assurance: Helps in minimizing unplanned maintenance by choosing IFBs less prone to permanent deformation at operating temperatures.

Practical Value: Using ASTM C210-95(2024) enables organizations to select and qualify insulating firebrick based on proven resistance to reheat-induced dimensional changes, supporting both operational efficiency and long-term thermal system integrity.

Related Standards

• ASTM C155 - Classification of Insulating Firebrick: Defines categories of IFB based on properties such as bulk density and allowable reheat change.
• ASTM C24 - Test Method for Pyrometric Cone Equivalent (PCE) of Fireclay and High-Alumina Refractory Materials: Relevant for assessing high-temperature capabilities of refractory products.
• ASTM E230/E230M - Specification for Temperature-Electromotive Force (emf) Tables for Standardized Thermocouples: Critical for accurate temperature measurement in the reheat test.
• ASTM E1256 - Test Methods for Radiation Thermometers (Single Waveband Type): Provides guidance for kiln temperature monitoring by optical or radiation thermometers.

Keywords

insulating firebrick, reheat change, permanent linear change, refractory materials, thermal stability, ASTM C210, kiln testing, industrial insulation, firebrick classification, high-temperature performance

By implementing ASTM C210-95(2024), stakeholders in the refractory and thermal insulation sectors ensure standardized, reliable, and globally recognized evaluation of insulating firebrick performance under reheat conditions.

Standards Content (Sample)

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.
Designation: C210 − 95 (Reapproved 2024)
Standard Test Method for
Reheat Change of Insulating Firebrick
This standard is issued under the fixed designation C210; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope method defines thermal stability by measurement of IFB’s
reheat change following 24 h at a test temperature.
1.1 This test method covers the determination of the perma-
nent linear (and volume) change of insulating firebrick upon 3.2 Since this test exposes the entire sample to an isothermal
reheating under prescribed conditions. temperature condition, the user should be aware that most
applications for IFB involve a thermal gradient which may
1.2 The values stated in inch-pound units are to be regarded
cause the IFB’s dimensions to change differentially.
as the standard. The values given in parentheses are for
information only.
4. Apparatus
1.3 This standard does not purport to address all of the
4.1 The test kiln shall be capable of maintaining the
safety concerns, if any, associated with its use. It is the
required temperature with a variation of not more than one half
responsibility of the user of this standard to establish appro-
a standard pyrometric cone over the hearth area during the
priate safety, health, and environmental practices and deter-
prescribed heating schedule. If a gas- or oil-fired kiln is used,
mine the applicability of regulatory limitations prior to use.
it shall be of the downdraft type and of such a design as not to
1.4 This international standard was developed in accor-
permit the flame from the burner to impinge upon the test
dance with internationally recognized principles on standard-
specimens. The kiln atmosphere during the test shall be kept as
ization established in the Decision on Principles for the
oxidizing as is practicable.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
5. Procedure
Barriers to Trade (TBT) Committee.
5.1 Test Specimens and Measurements:
2. Referenced Documents
5.1.1 The test specimens shall consist of three brick (Note 1)
1 1
2.1 ASTM Standards: measuring 9 in. by 4 ⁄2 in. by 2 ⁄2 in. or 3 in. (228 mm by
C24 Test Method for Pyrometric Cone Equivalent (PCE) of 114 mm by 64 mm or 76 mm) or three pieces of these
Fireclay and High-Alumina Refractory Materials dimensions cut out of larger shapes.
C155 Classification of Insulating Firebrick
NOTE 1—Three supporting brick from the same lot as the test specimens
E230/E230M Specification for Temperature-Electromotive
are required also, so that the test sample is comprised of six brick.
Force (emf) Tables for Standardized Thermocouples
5.1.2 Each specimen shall be labeled with ceramic paint,
E1256 Test Methods for Radiation Thermometers (Single
and before and after heating they shall be carefully measured
Waveband Type)
for length (Note 2), width, and thickness. Three measurements
(Note 3) to the nearest 0.02 in. (0.5 mm) shall be taken for each
3. Significance and Use
dimension and the average of these shall be used. Each
3.1 Insulating firebrick (IFB) are classified by their bulk
dimension shall be measured in three places along the longi-
density and reheat change (see Classification C155). This test
tudinal center line on opposite faces, one measurement at the
center of the line and one ⁄2 in. (13 mm) in from each edge.
Fig. 1 shows the location at which these measurements are to
This test method is under the jurisdiction of ASTM Committee C08 on
be made.
Refractories and is the direct responsibility of Subcommittee C08.03 on Physical
Properties.
NOTE 2—For classifying IFB according to Classification C155, obtain
Current edition approved April 1, 2024. Published April 2024. Originally
the reheat change from the 9 in. (228 mm) dimension measurements only.
approved in 1946. Last previous edition approved in 2019 as C210 – 95 (2019).
NOTE 3—Because of the large pore size of some IFB, it is difficult to
DOI: 10.1520/C0210-95R24.
measure by means of calipers directly on the brick surfaces. Accuracy may
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
be obtained by holding two small pieces of flat polished steel plate of
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on known thickness against the faces between which the dimension is to be
the ASTM website. obtained, and calipering on the outside steel surfaces rather than directly
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C210 − 95 (2024)
develop on the surface of the test brick, in which case remove
them by rubbing their surfaces very lightly with a fine abrasive
block before remeasuring in accordance with 5.1.2.
8. Calculation and Report
8.1 Reheat Change—Calculate the reheat change in percent
from the average measurement for the dimension obtained
before and after reheating.
8.2 Reheat Volume Change—When the reheat volume
change is requested, calculate it from the average measurement
for the three dimensions obtained before and after reheating, as
NOTE 1—The dots on the center line of each face are ⁄2 in. (13 mm) in
follows:
from each edge, and the cross on the axis is in the center. These positions
indicate the points at which three measurements for each dimensions are
V 5 V 2 V /V × 100 (1)
@~ ! #
o f o
to be made.
where:
FIG. 1 Test Brick Showing Measurement Locations
V = volume change, percent,
V = original volume, and
o
V = final volume.
f
against the brick surfaces. It is permissible to use a measuring device to
obtain the dimensions of the brick, provided the measurements are not
8.3 Report—When the test is conducted for evaluating IFB
affected by large pores in the surface.
in accordance with Classification C155, the average linear
5.2 Placing Test Specimens in Kiln: change for the 9 in. (228 mm) dimension only shall be re-
5.2.1 Place the test specimens in the kiln so that each will
ported; otherwise, or when specified, the average of the reheat
rest on a 9 in. by 2 ⁄2 in. or 3 in. (228 mm by 64 mm or 76 mm) change for the length, width, and thickness shall be reported
face. Place each specimen upon the 9 in. by 2 ⁄2 in. or 3 in. face
and, if requested, the average reheat volume change.
of a supporting brick that shall be from the same lot as the test
specimen. Place between the test specimen and the supporting
9. Precision and Bias
member a layer of suitable refractory material, that is nonre-
9.1 Interlaboratory Test Program—An interlaboratory test
active under the test conditions and passes an ASTM No. 16
program between six laboratories was conducted. Eac
...