ASTM C133-24 PDF

Full title and description

ASTM C133-24 — Standard Test Methods for Cold Crushing Strength and Modulus of Rupture of Refractories. This standard specifies laboratory procedures to determine the room-temperature compressive strength (cold crushing strength) and three-point flexural strength (cold modulus of rupture) of dried or fired refractory shapes and products.

Abstract

ASTM C133-24 provides methods to measure cold crushing strength and modulus of rupture for refractories. It defines specimen preparation, testing machine requirements, loading geometries, test rates, and reporting conventions (inch‑pound units as primary). The procedures are intended for research, manufacturing process control, engineering design, and procurement specifications for refractory products.

General information

• Status: Published.
• Publication date: Published March 31 / approved April 1, 2024 (effective April 1, 2024).
• Publisher: ASTM International (Committee C08 on Refractories, Subcommittee C08.01).
• ICS / categories: Refractories — ICS Code 81.080.
• Edition / version: C133‑24 (current revision, replaces earlier C133 editions such as C133‑97(2021)).
• Number of pages: Approximately 6 pages (typical published length for this test-method standard).

Scope

The standard covers determination of cold crushing strength (compressive) and cold modulus of rupture (three‑point bending) of dried or fired refractory shapes of all types. It specifies test sections for crushing strength and MOR, notes unit conventions (inch‑pound primary, SI in parentheses), and cautions that specimen size, face preparation, loading geometry, and grain‑to‑specimen size ratio can significantly affect results. The methods are not intended to measure elevated‑temperature performance.

Key topics and requirements

• Test methods for cold crushing strength (compressive) and cold modulus of rupture (three‑point bending).
• Specimen preparation guidance (size, face condition, orientation) and limits on specimen size relative to largest grain dimension.
• Apparatus requirements: standard mechanical or hydraulic compression/testing machines with appropriate sensitivity and calibration.
• Test procedure details: loading geometry, rate of load application, data recording and result calculation (reporting both compressive strength and MOR as applicable).
• Units and reporting: inch‑pound units are primary; SI conversions may be provided for information only.
• Referenced practices and related test methods (examples: ASTM C862, C1054, and E4 for specimen preparation and machine calibration).

Typical use and users

Used by refractory manufacturers, materials testing laboratories, quality control personnel, R&D engineers, procurement/specification writers, and end‑users evaluating refractories for furnaces, kilns, and other high‑temperature installations. Typical applications include product qualification, process control, comparative material evaluation, and contractual acceptance testing.

Related standards

Commonly referenced or related ASTM documents include practices for specimen preparation and pressing/drying (ASTM C862, C1054) and force‑calibration procedures (ASTM E4). The C133‑24 revision supersedes earlier C133 editions (for example C133‑97 and the 2021 reapproval). These related standards provide preparatory and calibration context required to perform C133 tests correctly.

Keywords

cold crushing strength, modulus of rupture, MOR, refractories, refractory brick, monolithic refractories, compressive strength, three‑point bending, specimen preparation, test method.

FAQ

Q: What is this standard?

A: ASTM C133‑24 is the 2024 revision of the test methods that determine the cold crushing strength and the cold modulus of rupture of dried or fired refractory shapes.

Q: What does it cover?

A: It covers specimen dimensions and preparation guidance, apparatus and calibration requirements, loading geometry and test procedures for compressive (cold crushing) and three‑point bending (MOR) tests, plus reporting conventions. It is intended for room‑temperature characterization, not high‑temperature performance.

Q: Who typically uses it?

A: Refractory manufacturers, independent testing labs, QA/QC and R&D engineers, and purchasers who specify or verify mechanical properties of refractory products.

Q: Is it current or superseded?

A: Current — the C133‑24 edition is a published revision (approved April 1, 2024) that replaces prior C133 editions/reapprovals. Users should confirm they have the latest issued text before testing.

Q: Is it part of a series?

A: It is part of ASTM Committee C08 activities on refractories; it references and is commonly used alongside other ASTM practices (for specimen preparation and calibration) but is a standalone test‑method standard rather than a numbered series.

Q: What are the key keywords?

A: Cold crushing strength; modulus of rupture; MOR; refractories; compressive strength; three‑point bending; specimen preparation; testing machine; room temperature.