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ASTM D2256 and D7269: Two Tensile Test Standards for Thread

Tensile strength is an important property to consider when selecting an industrial sewing thread(such as filament sewing thread), as it affects the strength and durability of the final product.

ASTM D2256 and ASTM D7269

Both ASTM D2256 and ASTM D7269 are test methods for measuring the tensile properties of yarns. However, there are some differences in the procedures and specifications of these two methods:

  • ASTM D2256 is designated as Tensile Properties of yarns by the single-strand method, which can apply to any industrial yarn.
  • ASTM D7269 is more specific for aramid yarns and is designated as the standard test method for tensile testing of aramid yarns.

Both ASTM D2256 and ASTM D7269 are test methods for measuring the tensile properties of yarns. However, there are some differences in the procedures and specifications of these two methods.

ASTM D2256 is a standard test method for determining the tensile properties of yarns by the single-strand method. This method involves clamping a sample yarn between two grips and then applying a controlled tensile load until the yarn breaks. The force and elongation at break are measured, and the tensile strength and elongation at break are calculated.

On the other hand, ASTM D7269 is a standard test method for determining the tensile properties of high-performance yarns using the skein method. This method involves making a skein of yarn and then clamping it between two grips. The yarn is then pulled at a constant rate until it breaks, and the force and elongation at break are measured. This test method is specifically designed for high-performance yarns, which have different characteristics than standard yarns.

In summary, ASTM D2256 is a general method for measuring the tensile properties of yarns, while ASTM D7269 is a specialized method for high-performance yarns. The appropriate test method to use will depend on the specific type of yarn being tested, as well as the intended application of the yarn.

Test report for both test methods

Although these are two different standards, the test results recorded for the two test methods using the same base materials are almost indistinguishable, the following results were obtained in a test demonstration project of Service Thread:

  • Test one is performed under the conditions of ASTM D7269 with an extension of 5 inches per minute. The breaking strength recorded is 71.61 pounds
  • Test two is performed under the conditions of ASTM D2256 with an extension of 12 inches per minute and the breaking strength is 70.84 pounds

The elongation at break for both samples is nearly identical and the breaking strength is also statistically the same.

The tensile strength of an industrial sewing thread

The tensile strength of an industrial sewing thread is typically measured using the ASTM D2256 standard test method. This method involves clamping a sample of the thread in a tensile testing machine, then applying a controlled load until the thread breaks. The force at which the thread breaks is recorded and the tensile strength is calculated as the breaking force divided by the cross-sectional area of the thread.

The specific tensile strength requirements for an industrial sewing thread will depend on the intended use of the sewn product. For example, heavy-duty applications such as tents or automotive upholstery may require threads with higher tensile strength than lighter-weight applications such as clothing or bedding. It is important to select a sewing thread with the appropriate tensile strength to ensure the sewn product can withstand the expected use and loads.

Additionally, other properties such as elongation, abrasion resistance, and chemical resistance may also be important to consider when selecting an industrial sewing thread.