ASTM C973-87(2020)

• Abstract:

  SIGNIFICANCE AND USE; 2.1 This practice defines a procedure that ensures consistent preparation of specimens for product testing and evaluation. ; 2.2 This practice can be used in the laboratories of producers, users, and general-interest parties for research and development or quality-control work. It is particularly useful for interlaboratory comparisons on products, for repetitive evaluations or comparisons of products or product equality, and in specifying a uniform preparation practice for specimens for acceptance testing. ; 2.3 In using this practice, it must be recognized that the structure of laboratory-pressed specimens may differ significantly from the structure of material gunned in field applications.; SCOPE; 1.1 This practice covers a procedure for preparing test specimens from basic refractory gunning products by pressing prepared material in a mold. After pressing, test specimens prepared from dolomitic mixes are subjected to a prescribed heat treatment. Specimens prepared in accordance with this procedure are intended for use in ASTM test methods. ; 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. ; 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.

• Status: Published
• Publication Date: 31-Oct-2020
• ICS: 81.080 - Refractories
• Technical Committee: C08 - Refractories
• Drafting Committee: C08.09 - Monolithics

Overview

ASTM C973-87(2020) is an international standard developed by ASTM International. This standard practice provides a uniform procedure for preparing test specimens from basic refractory gunning products by pressing prepared material into a mold. The primary goal is to ensure consistent specimen preparation for accurate testing and evaluation of refractory materials in laboratory settings.

The standard is applicable to producers, end-users, and other interested parties involved in research, development, and quality control of basic refractory gunning products. It is especially valuable for laboratories conducting interlaboratory comparisons, repetitive evaluations, acceptance testing, or product uniformity assessments.

Key Topics

• Specimen Preparation: Defines step-by-step methods for mixing, molding, pressing, drying, and-if required-heat treating test specimens from basic refractory gunning mixes, including specific procedures for dolomitic and non-dolomitic products.
• Equipment Requirements: Specifies essential laboratory apparatus such as mixers, presses, steel molds, furnaces, ovens, desiccators, and trowels needed for specimen preparation.
• Consistency and Comparability: Promotes reliable and reproducible specimen properties by standardizing sample preparation, supporting accurate quality assessments and interlaboratory comparisons.
• Batch Handling: Addresses the influence of batch size and timing, particularly for products with hydratable or quick-setting bonds, to minimize variation in specimen physical properties caused by premature reactions during pressing.
• Reporting: Outlines the required documentation-such as water content, drying time, and specimen size-to ensure traceability and facilitate interpretation of test results.

Applications

ASTM C973-87(2020) is particularly relevant for:

• Refractory Product Manufacturers: Ensuring quality control during production and providing reliable data to customers.
• Construction and Engineering Laboratories: Performing acceptance tests on basic refractory gunning materials used in industrial furnaces, kilns, and reactors.
• Research & Development: Comparing new formulations or evaluating the consistency and durability of refractory products.
• Quality Assurance Programs: Supplying a repeatable process for monitoring the consistency of refractory products over time or across multiple facilities.
• Third-party Testing Facilities: Enabling meaningful interlaboratory comparisons by using a standardized specimen preparation method.

Test specimens prepared following ASTM C973 are intended for subsequent evaluation using established ASTM test methods, ensuring results are accurate and directly comparable between labs and over time.

Related Standards

For comprehensive assessment and control of refractory products, consider the following related standards:

• ASTM C721: Standard Test Methods for Estimating Efficiency of Mechanical Mixers on Plastic Refractory Materials
• ASTM C133: Standard Test Methods for Cold Crushing Strength and Modulus of Rupture of Refractories
• ASTM C401: Standard Classification of Alumina and Alumina-Silicate Castable Refractories
• ISO 1927 Series: Monolithic (unshaped) refractories - various methods for preparation and testing

Practical Value

Implementing ASTM C973-87(2020) helps laboratories and manufacturers:

• Achieve consistent and reliable test results
• Ensure test specimens fairly represent the properties of basic refractory gunning products
• Facilitate product validation, compliance, and performance verification
• Support international trade and recognition by adhering to globally accepted standardization practices

Adherence to ASTM C973 strengthens quality assurance, boosts confidence in R&D results, and streamlines acceptance testing for refractory gunning materials.

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: C973 − 87 (Reapproved 2020)
Standard Practice for
Preparing Test Specimens from Basic Refractory Gunning
Products by Pressing
This standard is issued under the fixed designation C973; 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 2.3 In using this practice, it must be recognized that the
structure of laboratory-pressed specimens may differ signifi-
1.1 This practice covers a procedure for preparing test
cantly from the structure of material gunned in field applica-
specimens from basic refractory gunning products by pressing
tions.
prepared material in a mold. After pressing, test specimens
3. Apparatus
prepared from dolomitic mixes are subjected to a prescribed
heat treatment. Specimens prepared in accordance with this
3.1 Mixer, bench-type, Hobart or equivalent.
procedure are intended for use in ASTM test methods.
3.2 Press, mechanical or hydraulic.
1.2 The values stated in inch-pound units are to be regarded
3.3 Steel Molds.
as standard. The values given in parentheses are mathematical
3.4 Furnace.
conversions to SI units that are provided for information only
and are not considered standard. 3.5 Oven, air-circulating.
3.6 Desiccator.
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3.7 Trowel.
responsibility of the user of this standard to establish appro-
4. Procedure
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use. 4.1 Store the material to be tested at 85 6 2 °F (29.5 6
1 °C) for 24 h prior to testing. Dolomitic materials should be
1.4 This international standard was developed in accor-
stored in airtight containers.
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
4.2 Reduce the sample to the desired batch size with a
Development of International Standards, Guides and Recom-
sample splitter or by quartering, taking precautions to prevent
mendations issued by the World Trade Organization Technical
segregation. Sufficient material should be batched to provide at
Barriers to Trade (TBT) Committee.
least a 10 % excess over test specimen requirements.
4.3 Add the weighed, dry batch to the mixer and dry-mix at
2. Significance and Use
low speed for 30 s. Continue to mix at low speed while adding
the required amount of water (see 4.3.1) within 30 s. Wet-mix
2.1 This practice defines a procedure that ensures consistent
at low speed for 3 min.
preparation of specimens for product testing and evaluation.
4.3.1 Use the amount of water and mixing time (if different
2.2 This practice can be used in the laboratories of
from above) recommended by the manufacturer. The water
producers, users, and general-interest parties for research and
must be potable and at a temperature of 85 6 2 °F (29.5 6
development or quality-control work. It is particularly useful
1 °C). Measure the water addition to the nearest 0.1 % by
for interlaboratory comparisons on products, for repetitive
weight.
evaluations or comparisons of products or product equality,
4.4 Specimens of the desired size should be pressed imme-
and in specifying a uniform preparation pra
...