Military Food Pack Flex Test – ASTM F392 and Gelbo Method

Introduction to Military Food Pack Flex Testing

When it comes to operational reliability in extreme environments, the military food pack must remain intact through transportation, handling, and storage. To verify the durability of flexible barrier materials used in these packages, the flex test—commonly known as the Gelbo test—is essential. This testing method evaluates a material’s resistance to pinholing and delamination under repeated stress, ensuring the food remains protected and uncontaminated.

Flex Test, Gelbo Test, and the Role of Flex Durability Tester

The flex test, as described in ASTM F392, simulates the real-world mechanical fatigue that flexible packaging materials experience. During this process, the test specimen is subjected to a twisting and compressive motion—known as the Gelbo test—using a тестер прочности на изгиб. This equipment performs a series of defined twist-compression cycles to replicate the physical stress military packaging undergoes during logistics operations.

Gelbotest.com offers advanced flex durability testers engineered to meet ASTM F392 requirements, making them ideal for testing military food pack materials. Our systems ensure repeatable, accurate motion control for up to 20,000 flexing cycles, providing high-reliability data for quality assurance and R&D applications.

Understanding ASTM F392: Standard Guide for Flex Testing

ASTM F392 specifies two test procedures—Procedure A and Procedure B:

• Procedure A (Dry Flex): Used to evaluate pinhole formation on films and laminates without added moisture.
• Procedure B (Wet Flex): Adds water or another liquid between layers to simulate more aggressive conditions, such as condensation or immersion.

After completing the required number of cycles, the test specimen is examined for pinhole formation, delamination, or other structural failures using visual inspection or dye penetration methods. This allows manufacturers to quantitatively assess the durability of military food pack materials before deployment.

Why Flex Testing Matters for Military Food Packaging

In the defense industry, product failure is not an option. If a military food pack develops pinholes or delaminates, it risks food spoilage, contamination, or reduced shelf life. Flex testing helps material developers and quality control personnel ensure each packaging layer can withstand extreme field conditions such as vibration, pressure, and temperature variation.

Testing also supports compliance with military procurement specifications, where ASTM F392 is often referenced as part of qualification protocols. Incorporating this test early in product development minimizes the risk of material failure during deployment.

Gelbotest.com’s Solution for Military Packaging Quality Assurance

As a leading manufacturer of testing instruments, Gelbotest.com provides a high-precision Gelbo flex durability tester that fully conforms to ASTM F392. Our equipment supports both dry and wet flex testing modes, making it an ideal choice for military food pack material evaluation.

Whether you’re developing new packaging laminates or performing routine QA, our instruments deliver consistent, reliable data to help maintain the integrity of your products in the most demanding environments.

Implementing the flex test using the Gelbo test method according to ASTM F392 is critical for verifying the durability and safety of military food packs. With Gelbotest.com’s advanced тестер прочности на изгиб, you can ensure your packaging materials meet strict military and industrial standards for performance and reliability.