What materials are acceptable for fabricating cylinders and pressure vessels?

The correct answer highlights that steel, aluminum, and composite materials are widely accepted for fabricating cylinders and pressure vessels used in the transport and storage of CNG. These materials are chosen because they offer a combination of strength, durability, and resistance to high pressures, which is crucial for safe storage and handling of compressed gas.

Steel is commonly used due to its high tensile strength and ability to withstand the demanding conditions in which pressure vessels operate. Aluminum is favored in some applications as it is lighter than steel while still providing significant strength, which can be advantageous in mobile applications where weight is a concern. Composite materials, which often consist of a combination of materials such as high-strength fibers and resins, provide an alternative that is both lightweight and capable of withstanding high pressures, making them suitable for modern storage solutions.

In contrast, the other materials listed are not suitable for pressure vessels. Plastic and fiberglass may not withstand the high pressures involved in CNG storage. Wood and concrete lack the tensile strength required for such applications and are therefore not appropriate choices. Rubber and glass also fail to meet the necessary requirements for pressure resistance and safety in high-pressure environments. Thus, the selection of metals and specially engineered composites as acceptable materials is essential for safety and reliability in the design