ASTM D4831-00(2020)

• Abstract:

  SIGNIFICANCE AND USE; 2.1 This test method is designed to measure the load required to tear a leather strap fastened in a buckle. Tanners and leather buyers have found that this test gives an indication of the resistance of leather to tearing. ; 2.2 This test method should be suitable for specification acceptance, design purposes, manufacturing control, development, and research. The thickness of the specimen and direction of tear relative to the backbone will affect the uniformity of the test results. This test method may not apply when the conditions of the test employed differ widely from those specified in this test method.; SCOPE; 1.1 This test method is intended for use on all types of leather to determine the load required to tear a leather strap fastened in a buckle. This test method does not apply to wet blue. ; 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: 30-Nov-2020
• ICS: 59.140.30 - Leather and furs
• Technical Committee: D31 - Leather
• Drafting Committee: D31.01 - Vegetable Leather

Overview

ASTM D4831-00(2020) – Standard Test Method for Buckle Tear Strength of Leather outlines a consistent, reliable procedure for determining the force required to tear a leather strap when fastened in a buckle. Developed by ASTM International, this method is essential for both leather manufacturers and buyers, providing an objective measure of leather’s resistance to tearing, particularly in strain-prone applications such as belts, straps, and harnesses. The standard applies to all finished leather types except wet blue and is recognized for supporting quality assurance, product development, and specification verification across the leather industry.

Key Topics

• Buckle Tear Strength: This method measures the maximum load required to initiate tearing in a leather specimen secured in a buckle, reflecting the leather's durability and performance under stress.
• Test Scope: Applicable to a variety of leather products except wet blue leathers, ensuring broad industry relevance.
• Specimen Preparation: Specifies sample dimensions, preparation of a punched hole, and the importance of aligning the specimen’s long axis relative to the animal’s backbone for uniform results.
• Test Apparatus:
  • Spring-type gauge for precise thickness measurement.
  • Specific harness buckle and steel punch for consistent hole sizing.
  • Power-driven testing machine with accurate load indication and specialized grips to prevent slipping.
• Test Data Reporting: Results must include the sample’s average thickness and buckle tear strength, clearly documented for traceability and comparison.
• Units of Measurement: Uses inch-pound units as the standard, with SI unit conversions provided for informational purposes.

Applications

The ASTM D4831-00(2020) test method provides significant practical value for:

• Leather Tanners and Buyers: Establishes a benchmark for evaluating the tear resistance of leather used in belts, straps, and fashion accessories, assuring end-product quality.
• Product Specification and Acceptance: Supports contractual agreements and quality assurance processes by delivering standardized tear strength values for finished leather goods.
• Manufacturing Control: Facilitates in-process testing and process adjustment to maintain consistent product strength and durability.
• Design and Development: Guides researchers and product developers in selecting suitable leather materials and optimizing designs to meet specific strength requirements.
• Regulatory and Safety Compliance: Assists in demonstrating compliance with performance standards for critical applications in personal protective equipment (PPE), equestrian, automotive, and luggage sectors.

Related Standards

Professionals applying ASTM D4831-00(2020) may also find value in the following related standards:

• ASTM D4705: Standard Test Method for Stitch Tear Strength of Leather
• ASTM D2208: Standard Test Method for Breaking Strength of Leather
• ISO 3377-1: Leather - Physical and Mechanical Tests - Determination of Tear Load - Part 1: Single Edge Tear
• ISO 3377-2: Leather - Physical and Mechanical Tests - Determination of Tear Load - Part 2: Double Edge Tear

Practical Value

ASTM D4831-00(2020) is a critical standard for advancing the quality, consistency, and safety of leather products worldwide. By adhering to this test method, manufacturers and buyers ensure that leather goods meet durability requirements, reduce failure rates in use, and build trust through transparent and repeatable performance data. This standard supports global trade by aligning with internationally recognized principles for leather testing, making it an essential tool in both domestic and export markets.

Keywords: buckle tear strength, leather testing, ASTM D4831, physical properties of leather, tear resistance, quality assurance, leather industry standards.

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: D4831 − 00 (Reapproved 2020)
Standard Test Method for
Buckle Tear Strength of Leather
This standard is issued under the fixed designation D4831; 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 0.025 in. (10.2 6 0.6 mm) in diameter and a flat anvil 0.4 6
0.025 in. in diameter. The spring shall exert a force of 1 lbf
1.1 This test method is intended for use on all types of
(4.45 N) on the foot when the gauge reads 2 oz and 2 lbf (8.9
leather to determine the load required to tear a leather strap
N) when the gauge reads 12 oz.
fastened in a buckle. This test method does not apply to wet
blue. 3.2 Steel Punch, which will make a ⁄16 in. (4.8 mm)
diameter hole.
1.2 The values stated in inch-pound units are to be regarded
as standard. The values given in parentheses are mathematical
3.3 Harness Buckle, 1.25 in. (4.7 mm) with a 0.175 6
conversions to SI units that are provided for information only 0.005-in. (4.4 6 0.1-mm) diameter tongue. It shall be attached
and are not considered standard.
to a strong strap, 1.25 in. wide and at least 5 in. (127 mm) long.
The strap shall be equipped with a keeper located approxi-
1.3 This standard does not purport to address all of the
mately 0.75 in. (19 mm) from the buckle.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3.4 Testing Machine, power-driven. The applied load shall
priate safety, health, and environmental practices and deter-
be indicated on a dial, scale, or chart. The load indicator shall
mine the applicability of regulatory limitations prior to use.
record or indicate the maximum load at the time of rupture of
1.4 This international standard was developed in accor-
the specimen. The machine shall be equipped with a set of
dance with internationally recognized principles on standard-
grips for clamping the specimens.The faces of the grips should
ization established in the Decision on Principles for the
be knurled or otherwise roughened to prevent slipping of the
Development of International Standards, Guides and Recom-
specimen. The gripping surfaces shall be at least 1 by 1 ⁄2 in.
mendations issued by the World Trade Organization Technical
(25.4 by 38 mm). The grips shall be mounted with the longer
Barriers to Trade (TBT) Committee.
dimension perpendicular to the direction of the application of
the load. The speed of the power-activated grip shall be a
2. Significance and Use
uniform speed of 10 6 2 in. (254 6 50 mm)/min when running
2.1 This test method is designed to measure the load
free. The error of the machine up to a load of 50 lbf (222 N)
required to tear a leather strap fastened in a buckle.Tanners and
shall not exceed 2 %; at loads of more than 50 lbf the error
leather buyers have found that this test gives an indication of
shall not exceed 1 %.
the resistance of leather to tearing.
4. Sampling, Test Specimens, and Test Units
2.2 This test method should be suitable for specification
acceptance, design purposes, manufacturing control,
4.1 The specimen shall be a piece of leather 1 by 8 in. (25
development, and research. The thickness of the specimen and
by 200 mm). Note the direction of the long axis relative to the
direction of tear relative to the backbone will affect the
backbone.
uniformity of the test results. This test method may not apply
5. Procedure
when the con
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