Why Do Rubber Air Springs Fail from Ozone Cracking? How Wuxi ChuncoTech Rubber Protects Your Vehicle Suspension
In our last article, “Why Do Rubber Vibration Isolators Fail from Environmental Deterioration? How Wuxi ChuncoTech Rubber Ensures Long-Term Equipment Stability”, we solved degradation problems in isolators. Today, we address a specific failure mode for rubber air springs in commercial vehicles: ozone cracking. If you have ever asked “why do my truck air bags develop cracks in the rolling lobe,” ozone is the culprit. Air springs are made of rubber, which is susceptible to ozone attack. Over time, ozone in the atmosphere creates surface cracks that grow under flexing, leading to air leaks and suspension failure . At Wuxi ChuncoTech Rubber, we manufacture ozone-resistant rubber air springs using EPDM and CR compounds that do not crack. Here is what causes ozone cracking—and how our air springs last longer.
The Ozone Cracking Mechanism: Surface Attack Under Stress
Ozone (O₃) reacts with unsaturated rubber compounds (natural rubber, SBR, NBR) under stress. When the air spring flexes, the surface rubber is stretched, creating stress concentration points. Ozone attacks these points, forming cracks perpendicular to the stress direction. Cracks grow with time, eventually penetrating the rubber wall and causing air leaks .
Why are air springs vulnerable?
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Constant flexing: The rolling lobe of the bellows flexes with every bump, creating stressed surfaces .
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Ozone exposure: Air springs are under the vehicle, exposed to atmospheric ozone.
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Heat and environmental factors: High temperatures accelerate aging; cold climates make rubber more brittle .
How Wuxi ChuncoTech Rubber Prevents Ozone Cracking
EPDM and CR compounds: Our air springs use EPDM (for maximum ozone resistance) or chloroprene (CR) (for balanced ozone and oil resistance). These materials are inherently ozone-resistant—they do not crack .
Antiozonant protection: For applications requiring NR's dynamic properties, we add antiozonants (6PPD, IPPD) and a wax bloom that migrates to the surface, forming a physical barrier against ozone .
Protective cover layers: We can add a thin EPDM cover over an NR bellows, facing the ozone while the NR provides flex life.
Regular inspection guidance: We recommend checking air springs for horizontal cracks in the rolling lobe—the first sign of aging. Replacing springs before they leak prevents compressor failure and costly breakdowns .
Real-World Result: Transit Fleet Extends Air Spring Life
A transit bus fleet in a smoggy city was replacing air springs every 3 years due to ozone cracking. They switched to Wuxi ChuncoTech Rubber EPDM air springs. After 8 years, no ozone cracks were visible, and ride height remained stable.
Your Ozone-Resistant Air Spring Partner
Wuxi ChuncoTech Rubber manufactures ozone-resistant air springs for trucks, buses, and rail vehicles. We offer EPDM (maximum ozone resistance), CR (balanced ozone/oil resistance), antiozonant-protected NR, and custom bellows shapes for any platform.
Visit our website at https://www.chuncotechrubber.com/ to request an ozone-resistant air spring consultation.