ASTM C24-89(1999)e1

Standard Test Method for Pyrometric Cone Equivalent (PCE) of Fireclay and High Alumina Refractory Materials

SCOPE
1.1 This test method covers the determination of the Pyrometric Cone Equivalent (PCE) of fire clay, fireclay brick, high alumina brick, and silica fire clay refractory mortar by comparison of test cones with standard pyrometric cones under the conditions prescribed in this test method.  
1.2 The values stated in inch-pound units are to be regarded as 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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-Feb-2001
• ICS: 81.080 - Refractories
• Technical Committee: C08 - Refractories

Relations

• Replaced By: ASTM C24-01 - Standard Test Method for Pyrometric Cone Equivalent (PCE) of Fireclay and High Alumina Refractory Materials
• Effective Date: 10-Feb-2001
• Referred By: ASTM C27-98(2022) - Standard Classification of Fireclay and High-Alumina Refractory Brick
• Effective Date: 10-Feb-2001
• Referred By: ASTM C199-22 - Standard Test Method for Pier Test for Refractory Mortars
• Effective Date: 10-Feb-2001
• Referred By: ASTM C210-95(2019) - Standard Test Method for Reheat Change of Insulating Firebrick
• Effective Date: 10-Feb-2001
• Referred By: ASTM C1283-15(2021) - Standard Practice for Installing Clay Flue Lining
• Effective Date: 10-Feb-2001
• Referred By: ASTM C673-97(2022) - Standard Classification of Fireclay and High-Alumina Plastic Refractories and Ramming Mixes
• Effective Date: 10-Feb-2001
• Referred By: ASTM C71-12(2018) - Standard Terminology Relating to Refractories
• Effective Date: 10-Feb-2001
• Referred By: ASTM C1261-22 - Standard Specification for Firebox Brick for Residential Fireplaces
• Effective Date: 10-Feb-2001
• Referred By: ASTM F1097-17(2022) - Standard Specification for Mortar, Refractory (High-Temperature, Air-Setting)
• Effective Date: 10-Feb-2001

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
e1
Designation: C 24 – 89 (Reapproved 1999)
Standard Test Method for
Pyrometric Cone Equivalent (PCE) of Fireclay and High
Alumina Refractory Materials
This standard is issued under the fixed designation C 24; 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 (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
e NOTE—Editorial changes were made in Table 2 in October 1999.
1. Scope have been determined by the National Institute of Standards
and Technology when subjected to both slow and rapid heating
1.1 This test method covers the determination of the Pyro-
rates.
metric Cone Equivalent (PCE) of fire clay, fireclay brick, high
alumina brick, and silica fire clay refractory mortar by com-
5. Significance and Use
parison of test cones with standard pyrometric cones under the
5.1 The deformation and end point of a cone corresponds to
conditions prescribed in this test method.
a certain heat-work condition due to the effects of time,
1.2 The values stated in inch-pound units are to be regarded
temperature, and atmosphere.
as standard. The values given in parentheses are for informa-
5.2 The precision of this test method is subject to many
tion only.
variables that are difficult to control. Therefore, an experienced
1.3 This standard does not purport to address all of the
operator may be necessary where PCE values are being utilized
safety concerns, if any, associated with its use. It is the
for specification purposes.
responsibility of the user of this standard to establish appro-
5.3 PCE values are used to classify fireclay and high
priate safety and health practices and determine the applica-
alumina refractories.
bility of regulatory limitations prior to use.
5.4 This is an effective method of identifying fireclay
2. Referenced Documents variations, mining control, and developing raw material speci-
fications.
2.1 ASTM Standards:
5.5 Although not recommended, this test method is some-
C 71 Terminology Relating to Refractories
times applied to materials other than fireclay and high alumina.
E 11 Specification for Wire-Cloth Sieves for Testing Pur-
Such practice should be limited to in-house laboratories and
poses
never be used for specification purposes.
E 220 Method for Calibration of Thermocouples by Com-
parison Techniques
6. Procedure
3. Terminology 6.1 Preparation of Sample:
6.1.1 Clay or Brick—Crush the entire sample of fire clay or
3.1 Definitions—For definitions of terms used in this test
fireclay brick, in case the amount is small, by means of rolls or
method, see Terminology C 71.
a jaw crusher to produce a particle size not larger than ⁄4 in. (6
4. Summary of Test Method
mm). If the amount is large, treat a representative sample
obtained by approved methods. Then mix the sample thor-
4.1 This test method consists of preparing a test cone from
oughly and reduce the amount to about 250 g (0.5 lb) by
a refractory material and comparing its deformation end point
quartering (see Note 1). Then grind this portion in an agate,
to that of a standard pyrometric cone. The resultant PCE value
porcelain, or hard steel mortar and reduce the amount again by
is a measure of the refractoriness of the material.
quartering. The final size of the sample shall be 50 g and the
4.2 Temperature equivalent tables for the standard cones
fineness capable of passing an ASTM No. 70 (212-μm) sieve
(equivalent to a 65-mesh Tyler Standard Series). In order to
This test method is under the jurisdiction of ASTM Committee C-8 on avoid excessive reduction to fines, remove them frequently
Refractories and is the direct responsibility of Subcommittee C08.07 on High
during the process of reduction by throwing the sample on the
Alumina, Silica, and Special Refractories.
sieve and continuing the grinding of the coarser particles until
Current edition approved July 28, 1989. Published November 1989. Originally
all the sample passes through the sieve (see Note 2). Take
issued as C 24 – 19 T. Last previous edition C 24 – 84 (1988).
Annual Book of ASTM Standards, Vol 15.01.
Annual Book of ASTM Standards, Vol 14.02.
4 5
Annual Book of ASTM Standards, Vol 14.03. Detailed requirements for this sieve are given in Specification E 11.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
C24
precautions to prevent contamination of the sample by steel
particles from the sampling equipment during crushing or
grinding.
NOTE 1—Take care during the crushing and grinding of the sample to
prevent the introduction of magnetic material.
NOTE 2—The requirement to grind the coarser particles is particularly
important for highly siliceous products; excessively fine grinding may
reduce their PCE by as much as two cones.
6.1.2 Silica Fire Clay (see 3.1)—In the case of silica fire
clay, test the sample obtained by approved methods as received
without grinding or other treatment.
6.2 Preparation of Test Cones:
6.2.1 After preparing samples of unfired clays (Note 3), or
of mixes containing appreciable proportions of raw clay, in
accordance with 6.1.1, heat them in an oxidizing atmosphere in
the temperature range from 1700 to 1800°F (925 to 980°C) for
not less than 30 min.
NOTE 3—Some unfired clays bloat when they are formed into cones and
are carried through the high-temperature heat treatment prescribed in 5.4.1
without preliminary calcining. The substances that cause bloating can, in
most cases, be expelled by heating the clay samples before testing.
6.2.2 The clay sample may be given the heat treatment
prescribed in 6.2.1 after it has been formed into a cone (see
NOTE 1—Dimensions are in inches.
6.2.3), but this procedure has been found not as effective as the
SI Equivalents
treatment of the powdered material. If cones so prepared bloat
during the PCE test, heat a portion of the original sample in its
powdered condition as prescribed in 6.2.1 and then retest it.
in. mm
6.2.3 Thoroughly mix the dried sample, and after the
0.075 1.90
addition of sufficient dextrine, glue, gum tragacanth, or other 0.272 6.91
0.281 7.14
alkali-free organic binder and water, form it in a metal mold
1.081 27.46
into test cones in the shape of a truncated trigonal pyramid with
1.125 28.58
its base at a small angle to the trigonal axis, and in accordance
FIG. 1 Standard Pyrometric Test Cone
with dimensions shown in Fig. 1. In forming the test cone use
the mold shown in Fig. 2.
face outward, if so desired.
6.3 Mounting:
6.4 Heating:
6.3.1 Mount both the test cones and the Standard Pyromet-
6.4.1 Perform the heating in a suitable furnace, operating
ric Cones on plaques of refractory material that have a
with an oxidizing atmosphere, at rates to conform to the
composition that will not affect the fusibility of the cones (see
following requirements (see Note 6 and Note 7). It is advisable,
Note 4). Mount both test and PCE cones with the base
but not mandatory that the furnace temperature be controlled
embedded so that the length of the sloping face of the cone
with a calibrated thermocouple or radiation pyrometer con-
above the plaque shall be ⁄16 in. (24 mm) and the face of the
nected to a program-controlled recorder.
cone (about which bending takes place) shall be inclined at an
6.4.1.1 For PCE tests expected to have an end point of PC
...