Air springs
Manufacturers of air springs for OEM and aftermarket use are also refining products to improve ride quality for cargo and equipment and, importantly, for drivers. Another result of a smoother ride is reduced maintenance costs.
Firestone Industrial Products provides its Airide Integrated Primary Air-Damping System, which it says is often lighter than a hydraulic damper and eliminates the need for damper brackets and hardware. The company’s Primary Air-Damping spring offers a full-load range, and in testing according to the company has shown a reduction in the transmission and frequency of vibration when compared to traditional air spring/shock absorber or air spring/hydraulic damper configurations.
ContiTech Air Spring Systems for commercial vehicles—offered in ContiTech and Phoenix brands for the air spring replacement market—are based on the company’s experience as an original equipment manufacturer. In heavy commercial vehicles, air suspension systems from ContiTech offer a quiet and smooth drive, according to the manufacturer. Even under heavy loads, they effectively counteract jolts and reduce vibrations, ContiTech stated. Sleeve-type air springs in driver cabs and seats minimize the stress on the driver and enhance comfort.
ContiTech also offers original air springs developed for original equipment that meet the highest quality standards demanded by vehicle manufacturers to the replacement parts market.
Design impacts
Also driving some air suspension design, is the federal Bridge Formula, which limits the weight-to-length ratio of a vehicle crossing a bridge, and provides a consistent way to determine the maximum allowable weight that any set of axles on a vehicle may carry on the Interstate highway system. Also, to meet state and provincial requirements from a suspension 
system design standpoint, the main considerations are capacity and axle spacing. Bridge laws don’t differentiate by suspension design or type but by working directly with OEMs, suspension system providers help determine which product is best suited to each configuration and application. Overall, air suspension manufacturers remain focused on stability, ride quality, weight savings and cost effectiveness.
