Evaluation of Large Tow-Size Carbon Fiber for Reducing the Cost of CNG Storage Tanks

The performance of large tow-size carbon fiber was evaluated to determine any design impacts that would prohibit their introduction into the fabrication process of compressed natural gas (CNG) storage tanks. The evaluation was based on manufacturing process trials and mechanical property tests. The tests consisted of impregnated strand, composite ring, and composite subscale cylinder tests for static strength, fatigue, and stress rupture. Modifications required in the wet-filament winding process are documented as well as the development of test methodologies required for testing large tow-size impregnated strands.