Pressure Vessels Part 4: Fabrication, Inspection and Testing, and Acceptance
Pressure vessels are specialized containers used to store or transport gases and liquids under pressure, either significantly higher or lower than the surrounding atmospheric pressure. These containers are highly regulated and must meet strict safety standards to ensure they can withstand the extreme pressures they are subject to. Examples of pressure vessels include boilers, compressed air tanks, propane tanks, heat exchangers, and chemical reactors. In addition to steel, pressure vessels can also be made from aluminum or composite materials. Pressure vessels can be either spherical or cylindrical in shape and range in size from small tanks one person can carry to massive industrial vessels several stories tall. Regardless of their size or shape, all pressure vessels share one common goal: safely contain their contents at high pressures. Pressure vessels are used on space vehicles to store a variety of consumable commodities in liquid or gaseous form over a wide range of pressures and temperatures. The stored commodities can be used as pressuring, propellants, pneumatic gases, hydraulic fluids, power reactants, coolants, purge gases, or sources of breathable atmosphere. The pressure vessels themselves can be designed with any geometry; however, due to packaging efficiency and manufacturing considerations, they are typically spherical or cylindrical in shape and designed primarily for the storage of pressurized fluids.