ASTM D 3296 FEP-Fluorocarbon Tube

Scope:

FEP-fluorocarbon tubing made with extrusion resins made of tetrafluoroethylene and hexafluoropropylene that is used for electrical, mechanical, chemical, and medicinal applications falls under the ASTM D 3296 Standard Specification. To emphasize the unsuitability of recycled content for FEP tubing in certain applications and the requirement for purity and integrity in its composition and production, it specifically emphasizes virgin materials and excludes recycled materials.

Test Procedure:

A standard specification called ASTM D 3296 requires that the test method properties listed there be determined using the following techniques.

The first part mentions the determination of inside diameter according to Method D1675, with the condition that individual measurements should not exceed the specified tolerances. This indicates a rigorous quality control measure for ensuring the precise size of the inside diameter of the material.

The following section addresses the measurement of wall thickness, again referencing Method D1675 and specifying that measurements should not exceed tolerances listed in the aforementioned tables. This emphasizes the importance of maintaining consistent wall thickness in the material. The next point discusses the determination of specific gravity using Method A of Test Methods D792. It suggests adding a wetting agent, like liquid detergent, to the water used in the test to ensure complete wetting of the specimen. This step helps ensure accurate measurements of specific gravity.

The paragraph touches on the testing of tensile strength and elongation, which provides detailed procedures for conducting these tests. The testing speed is specified at 50.8 mm (2 in.)/min, and the results are to be averaged for longitudinal and transverse specimens separately. Additionally, it mentions the need to discard specimens that break in the testing machine and conduct new tests, underscoring the importance of reliable data in assessing the material’s tensile properties.

For tubing with an inside diameter of 15.9 mm (0.625 in.) and larger, the testing protocol involves determining tensile strength and elongation in both the longitudinal and transverse directions. This is done following the guidelines set in Specification D2116. This suggests a comprehensive evaluation of the material’s tensile properties for larger-diameter tubing.

In contrast, tubing with an inside diameter less than 15.9 mm (0.625 in.) up to 2.3 mm (0.090 in.) requires a slightly different approach. Tensile strength and elongation are determined only in the longitudinal direction, again following the specifications outlined in D2116. To prepare specimens for this testing, the tubing is slit parallel to its axis and flattened before punching out the required specimens.

For tubing with an inside diameter of less than 2.3 mm (0.090 in.), the testing methodology differs significantly. Specimens are tested as filaments, and they are prepared with non-slip loop knots at each end of the specimen, resulting in a total length of 34.9 mm (13⁄8 in.). This approach recognizes the unique characteristics and challenges posed by very small-diameter tubing.

Firstly, the dielectric breakdown voltage is determined by Test Methods D149. For tubing with a nominal diameter less than 4.80 mm (0.189 in.), a tight-fitting mandrel is used as the inner electrode, and metal foil approximately 19.1 mm (3⁄4 in.) wide serves as the outer electrode. This method ensures accurate measurement of dielectric breakdown voltage for smaller-diameter tubing.

For all other tubing, which includes larger diameters, a different approach is taken. The tubing is slit along the longitudinal axis and flattened before conducting the dielectric breakdown voltage test.

Next, the testing protocol involves assessing dimensional stability. Three specimens, each measuring 305 mm (12 in.) in length to the nearest 1.6 mm (1⁄16 in.), are cut and placed in a circulating-air oven at 200 ± 2°C for 3 hours. Afterward, the specimens are removed from the oven and allowed to cool to 23 ± 1°C. The change in length, calculated as a percentage of the original length, indicates the tubing’s dimensional stability under heat conditions.

Finally, the heat resistance of the tubing is examined using the same specimens as tested for dimensional stability. The tubing should exhibit no cracks or splitting, confirming its ability to withstand high-temperature environments.

Read more: ASTM D6737 Bulk Density of Tapered Paintbrush Filaments

Test Specimen:

FEP-Fluorocarbon Tube is used as the test specimen according to ASTM D 3296 standard test specifications.

Data:

Using conditions to conduct tests at the Infinita laboratory temperature of 23  ± 2°C (73.4  ± 3.6°F), ASTM D 3296 standard test specification is used. It is not necessary to maintain a consistent humidity level in referee instances. The Infinita laboratory environment with 50%,  ± 10% relative humidity shall be used.

Conclusion:

ASTM D 3296 is the only acceptable standard specification for FEP-Fluorocarbon Tubes. It painstakingly lays out the specifications and quality control procedures required to guarantee the precise dimensions, specific gravity, and tensile properties of these tubes, highlighting their appropriateness for crucial applications across numerous industries. Also learn about ASTM D 3295 about PTFE Tubing.