All components in contact with oxygen must be made of corrosion-resistant materials with good thermal and electrical conductivity, such as phosphor bronze, aluminum alloy, copper alloy, stainless steel, or copper-plated. All parts must undergo rigorous degreasing before assembly, and the use of organic compounds is strictly prohibited. Contact with oil is strictly prohibited; water, glycerin, or oil-free lubrication should be used, employing labyrinth seals and other technologies to prevent lubricant leakage or oxygen outflow. To prevent rust formation, components are often made of stainless steel or have a copper-plated surface, and filters are installed in the intake pipe and other areas.
To control temperature rise and risk, the design typically employs a low piston speed (e.g., 200 rpm) and a low airflow velocity within the pipes. Exhaust temperature should not be too high; when using water lubrication, it should not exceed 100-120°C; when using an oil-free lubrication structure filled with PTFE, it should not exceed 160°C. The pressure ratio of each stage should not be too high.
Core sealing technologies include labyrinth seals for shaft seals, modified PTFE materials for dynamic seals such as piston rods, and static seals using fluororubber O-rings.