Toughness Testing of an All-Composite Fuel Container for Natural Gas Vehicles 931785
The durability of fuel containers constructed with composite materials may vary depending on design and materials of construction. Properly designed cylinders reinforced with either carbon, fiberglass, Kevlar®, or a combination thereof have proved to be sufficiently durable for the Natural Gas Vehicle fuel container application. Generally, fiberglass reinforcement is the most durable with respect to physical damage; and carbon fiber reinforcement is more susceptible to physical damage, but provides superior fatigue and environmental resistance. This paper discusses the durability tests (bonfire, gunfire, drop, pendulum impact, and flaw tolerance) required by the American National Standard (ANSI), AGA NGV2, Basic Requirements for Compressed Natural Gas Vehicle (NGV) Fuel Containers; and the results of these tests performed on two (2) lightweight “all-composite” fuel container configurations. The ANSIIAGA NGV2 standard requires extensive qualification tests to insure that fuel containers are sufficiently durable and damage-tolerant to safely withstand the environment and operating conditions in an automotive environment. These durability tests demonstrate the effect on tank integrity of damage due to anticipated adverse handling and operating conditions, as well as more severe damage, such as puncture and fire. The lightweight “all-composite” containers used in this test program complied with ANSIIAGA NGV2, and used a thermoplastic liner, aluminum bosses and a carbonlfiberglass hybrid overwrap. These test results demonstrate that these lightweight “all-composite” fuel containers meet the rugged test requirements of ANSIIAGA NGV2.