Air springs contain a column of air in a rubber bellow or sleeve to provide suspension, isolation, or actuation. They are found in vehicle suspension systems, sometimes in conjunction with coil springs, and are used to insulate vibration in equipment U linear or angular actuators.
Air springs use an air compressor to fill and empty the malleable air bladder. The weight attaches to a piston or bead plate directly supported by the air with slight deflection, rather than the rubber liner, which merely holds the gas. A self-leveling mechanism is commonly used to keep the load on the air spring steady, and a second coil spring is occasionally added into the design. Electronic air spring systems are also available and can monitor air pressure, filter compressor air to prevent damage to the rubber bellows, & include a lock to hold air inside the spring in the event of compressor or airline failure.
Air spring composition
Air fitting: A tapped hole through which the air compressor supplies the spring with air.
Nut/bolt/mount: The way the air spring is attached to the component. Some air springs have a bolt and air-fitting combo mechanism built in.
Bead plate: A crimped metal plate that encloses and attaches the spring. Typically, this is forged steel, cast zinc alloy, or cast aluminum.
Bellows: A physical, multi-layer material that holds compressed gas. It is typically constructed of neoprene or rubber.
Girdle: A piece of metal that separates the bellows chambers in convoluted air springs.
Bumper: An optional layer of cushioning that protects the piston if the air spring fails.
Piston: A component attached to the machinery that requires suspension, supported by the enclosed air. Additional hardware is generally used to secure the piston housing.
Types of air springs
Aside from custom-fabricated air springs, three types of market-ready air springs are available.
Crimped, convoluted bellows with a permanent crimp in the plate that connects the bellow to the bead plate. These are useful for vibration isolation & linear or angular actuation. However, they are not suitable for automobile suspensions.
Sleeve bellows with an external clamp that secures the bellows to the bead plate. This form of air spring offers high vibration isolation but only linear actuation. They are uncommon suspensions.
Rolling lobe bellows use a piston instead of a bead plate at one end of the bellows. This is most popular in automobile suspensions & is not recommended for vibration isolation.
Air spring specifications
Installation
Despite having identical capabilities, air springs are far less expensive than pneumatic cylinders & other springs. In addition, air springs have a small footprint when deflated, making them easy to operate & attach to machinery.
Maintenance
Air springs have low maintenance requirements, & some manufacturers claim that their air springs are maintenance-free. In addition, air springs do not need to be lubricated, & they do not have seals or guides that might get misaligned or broken like conventional springs. While air spring bellows are susceptible to dry rot, this can take years to develop. Still, air springs should be stored at room temperature in dry, dark areas.
Environment
Air springs are suitable for most industrial and commercial applications because of their longevity & simplicity. Because rubber and neoprene are subject to dry rot, dehumidified circumstances may reduce an air spring’s service life. Rubber and neoprene are suitable for high or low-temperature applications. However, they have significantly less heat tolerance than metal spring choices. While neoprene is ideal for temperatures up to 65°C, it should not be used below -40°C, and rubber should not be used in temperatures below -60°C.
Applications
Air springs are most commonly used as actuators in amusement park attractions, packing equipment, clutch systems, conveyor belts, and scissor lifts. However, they also serve as vibration insulators in centrifuges, commercial washing machines, measuring and weighing apparatus, & textile looms. While the air spring impacted several sectors, including oil, logging, construction, & manufacturing, it is most visible in the vehicle industry, where it is employed in suspensions for automotive manufacturers.
Contact Air Spring Supply Company for details
If you need more information about air springs & the best type for you, contact Air Spring Supply Company, South Africa’s sole distributor for the Firestone Industrial Products Company.
