Fiber wound composite gas cylinders are generally composed of inner lining, fibers, resins, etc.
The inner wall of the composite gas cylinder inner lining is directly in contact with the medium, and its main functions are airtightness, anti-corrosion, temperature resistance, and pressure resistance; Therefore, it is required that the lining material have good airtightness, corrosion resistance, temperature resistance, high strength, and high toughness
There are two commonly used lining materials: aluminum and plastic
The main function of fiber winding reinforced composite material layer is to ensure that the gas cylinder has sufficient strength, stiffness, and stability under stress The composite material winding layer bears the vast majority (75%~95%) of the pressure load, with fibers as the main load-bearing body, and resin plays a bonding role on the fibers, distributing and transmitting loads between them;
Therefore, selecting high-strength and highly elastic reinforcing fibers and high-performance resins is an important measure to improve the load-bearing capacity of structures High performance composites such as high-strength glass fiber epoxy resin or carbon fiber epoxy resin and Kevlar fiber epoxy resin are usually used.
Composite material gas cylinders are generally classified into two methods: firstly, according to the application field, they are divided into:
1. Fuel gas cylinders for natural gas, hydrogen, and other fuel vehicles;
2. Used for respirator systems, including backpack mounted respirators, small respirators, and breathing masks for escape;
3. Used for aviation or navigation, mainly including escape slide inflation devices and aviation oxygen absorption devices;
4. Liquefied gas cylinders for household use, etc
Classification by liner material and reinforcement material: According to liner material, it can be divided into metal liner wrapped gas cylinders and plastic liner wrapped gas cylinders; It can also be divided into high-strength glass fiber wound gas cylinders, carbon fiber wound gas cylinders, aramid fiber wound gas cylinders, etc. according to the reinforcing materials Due to the advantages of good sealing, strong fatigue resistance, long cycle life, high stability, and light weight, aluminum liners are currently widely used in carbon fiber wound gas cylinders.
Fiber wound composite gas cylinders have the following advantages:
1. Light weight, good rigidity, and high strength;
2. The fatigue failure of metal materials is usually a sudden failure without obvious omen, and the combination of reinforcement and matrix in composite materials can not only effectively transfer the load, but also prevent the crack growth, which improves the fracture toughness of gas cylinders;
3. When a large number of reinforced fibers in composite materials cause material overload and a few fibers break, the load will be quickly redistributed to the undamaged fibers, so that the entire gas cylinder will not lose its load-bearing capacity in a short period of time;
4. Composite gas cylinders will not produce dangerous fragments when damaged by impact or high-speed impact, thereby reducing or avoiding injury to personnel;
5. It can meet the requirements of corrosion resistance without special treatment.
