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The pressure - bearing capacity of double - wall fuel tanks varies depending on their materials, structure, and manufacturing process.
Typically, for double - wall fuel tanks with an inner wall made of 6 - mm - thick Q235 - B steel plate and an outer wall of reinforced glass - fiber layer with a thickness of 2.5 mm or more, they can generally withstand a certain level of pressure3. The steel inner wall provides basic strength, and the glass - fiber - reinforced outer wall has good compression and shock resistance, which can enhance the overall pressure resistance of the tank3. Such tanks are often used in some applications where the pressure is not extremely high, and they can meet the normal use requirements.
There are also double - wall fuel tanks made of carbon steel and laminated fiberglass. These tanks have a partition with mechanical resistance by folds, which can dissipate forces up to 20 tons of pressure between the compartments. This type of tank is designed to have high resistance to continuous fueling and defueling of the compartments, indicating that it has a good ability to withstand pressure changes during use.
In addition, FRP double - wall fuel storage tanks usually have a pressure - bearing capacity of less than 6.4 MPa12. They have the advantages of pressure resistance, anti - aging, corrosion resistance, and long service life12. Through the design of the structure - layer thickness, winding angle, and wall thickness, the pressure - bearing capacity of the tank can be adjusted to a certain extent to meet different application requirements13.
However, it should be noted that the specific pressure - bearing capacity of double - wall fuel tanks needs to be determined according to the actual product specifications and the relevant standards and regulations followed.