ASTM D 3295: PTFE Tubing, And Spiral Cut Tubing

Scope:

The ASTM D 3295 specification outlines the requirements for PTFE tubing, including spiral cut and miniature beading tubing, both of which are made using PTFE resin produced in compliance with Specification D4895’s specifications. It offers a thorough framework for guaranteeing the dependability and quality of these PTFE-based goods, making it easier for them to be used in a variety of applications across numerous industries.

Test Procedure:

This ASTM D 3295 requirement Use the following test methods to identify the attributes listed in this specification.

The internal diameter of the PTFE tubing shall be measured using Test Method D1675 following this specification. The steps in Test Method D1675 must be followed in order to ascertain the wall thickness, and pitch must be computed by measuring the cut. Additionally, it is necessary to follow the steps outlined in Test Method D1675 to ascertain the outside diameter of microbeading. These procedures offer a thorough framework for evaluating these vital characteristics, with a focus on adhering to set tolerances to guarantee consistent and high-quality products.

To comply with Specification D4895, the melting point must be determined using a shave from the tubing rather than a molded disk. Through the use of Test Methods D792’s Method A, which includes the addition of two drops of liquid detergent to the water to lower surface tension and enable thorough specimen soaking specific gravity is measured. Test specimens for weight loss evaluation must weigh at least 50 g and be baked in a forced-draft oven for three hours at 300± 5°C (572 ±9°F) to comply with Test Method D1675. These processes guarantee reliable evaluation of attributes such as melting point, specific gravity, and weight loss.

To assess tensile strength and elongation properties. Test results for longitudinal and transverse specimens must be averaged separately. The evaluation of tensile properties should align with Test Method D638, except for specific exceptions. Utilize the designated test specimen and die identified in Test Method D1708. Maintain an initial jaw separation of 22.2 ± 0.13 mm (0.875 ± 0.005 in.) and a testing speed of 51 mm/min (2 in./min). Ensure that specimens are clamped with approximately equal lengths in each jaw. Elongation should be determined from the chart and expressed as a percentage of the initial jaw separation. For tubing with an inside diameter of 15.9 mm (0.625 in.) and above, both longitudinal and transverse tensile strength and elongation should be determined. To prepare specimens, slit the tubing parallel to the axis and flatten it before punching out specimens.

The dielectric breakdown voltage of the tubing should be determined following Test Method D1675, either in air or oil. In cases of dispute, testing must be conducted in oil. For dimensional stability assessment, three specimens, each measuring 305 mm (12 in.) in length with precision to the nearest 1.6 mm (1/16 in.), are cut. These specimens are then placed on steel mandrels with a diameter 5 to 10% less than the inside diameter of the specimen and subjected to a circulating-air oven at 260 ± 5°C (500 ± 9°F) for 3 hours. After removing the specimens from the oven and cooling them to 23 ± 2°C (73.4 ± 3.6°F), measure the length to the nearest 1.6 mm (1/16 in.), as well as the diameter and wall thickness. Calculate the change in length, diameter, and wall thickness as percentages of their original values. Regarding heat resistance, three specimens, each 305 mm (12 in.) long, should be placed in a circulating-air oven at 260 ± 5°C (500 ± 9°F) for 5 hours.

For improvement, it might be helpful to specify whether the dielectric breakdown voltage testing in air or oil is dependent on specific conditions or requirements. Additionally, clarify any criteria for dispute resolution in referee cases. Furthermore, organize the steps for dimensional stability and heat resistance testing into a structured list for easier comprehension.

Test Specimen:

PTFE tubing is used as the test specimen in the ASTM D 3295 standard test procedure.

Data:

Conditions-based Standard Test Method ASTM D 3295 Tests should be performed at the Infinita laboratory’s standard temperature of 23.±2 C (73.4± 3.6 F). 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:

As a result, ASTM D 3295 defines critical requirements for PTFE tubing, tiny beading, and spiral-cut tubing, providing consistency in both the quality and performance of these specialty goods.