Donut Springs
At AB Pneumatics, Donut Rubber Springs are our core product and technical speciality. Designed and developed through decades of engineering experience, these high-performance vibration isolation springs deliver reliable, long-lasting solutions for heavy-duty industrial applications where vibration, shock and noise can impact equipment performance, safety and maintenance.
Our Donut Springs are trusted by OEMs, system integrators and maintenance teams globally because they combine robust load-bearing capability with outstanding vibration attenuation, outperforming traditional steel coil springs in many applications.
Designed to suit the application, various sizes can be produced from larger springs with fabric reinforcement for high load carrying capacity, to smaller anti-vibration solid rubber springs.
WHAT ARE DONUT SPRINGS?
Donut Springs are fabric-reinforced rubber vibration isolators with a hollow centre designed to fit securely on mounting pins. The combination of a solid rubber core and reinforced fabric layers enables high load support while isolating vibration and reducing transmitted forces.
Unlike steel springs, rubber-based donut springs offer a more consistent natural frequency across varying loads, excellent corrosion resistance, virtually maintenance-free operation and better tolerance to environmental conditions.
Key Benefits & Performance Features
Superior Vibration Isolation
Delayed resonance and low natural frequency deliver effective vibration control in demanding frequency ranges, protecting structures and sensitive components.
High Load Capacity & Stability
Fabric reinforcement dramatically increases load-bearing capability while maintaining vibration isolation performance across a range of dynamic loads.
Shock & Impact Absorption
Rubber’s inherent damping characteristics help dissipate shock energy, reducing peak forces on machinery and support structures.
Maintenance-Free Design
With no moving parts or mechanical pivots, Donut Springs provide long service life with minimal upkeep — lowering operating costs and boosting uptime.
Compact, Corrosion-Resistant Construction
A compact design helps save installation space and offers superior performance in damp, abrasive or corrosive environments where steel springs may degrade.
Technical Support & Project-Led Engineering
AB Pneumatics doesn’t just supply Donut Rubber Springs — we provide engineered vibration isolation solutions backed by practical experience, technical analysis and validated testing.
Our Technical team works closely with customers throughout the full lifecycle of a project, from early concept through to final implementation and optimisation. This ensures Donut Springs are correctly specified, validated and integrated to deliver predictable, long-term performance.
Our technical support includes:
Application Assessment & Load Evaluation
Review of operating conditions, static and dynamic loads, installation constraints and vibration characteristics to ensure isolation performance is appropriate for the application.
Donut Spring Selection & Sizing
Guidance on stiffness, load range, deflection and natural frequency, ensuring the selected Donut Spring delivers effective vibration isolation without compromising stability or durability.
Custom Donut Spring Design & Specification
Development of bespoke Donut Springs where standard products are not suitable, including modified load ratings, reinforcement configurations or geometry to meet specific project requirements.
Performance Validation & Testing Support
Access to in-house testing using our Instron 8801 servohydraulic test machine, enabling static, dynamic, cyclic and fatigue testing to confirm real-world performance and support data-led decision making.
On-Site & Project Engineering Support (where required)
Practical engineering input during installation, commissioning or troubleshooting to ensure Donut Springs perform as intended in service.
We work with OEMs, consulting engineers and project teams to integrate Donut Springs logically into designs, ensure correct performance outcomes, and resolve application challenges efficiently. To speak with Thomas or Steven about projects or technical support, please contact us below:
common selection guide
| Unloaded Size | Minimum Working Loading | Maximum Working Loading | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Donut Spring | Outside Diameter (mm) | Inside Diameter (mm) | Free Height (mm) | Minimum Loading (kN) | Compressed Height (mm) | Natural Frequency (Hz) | Maximum Loading (kN) | Compressed Height (mm) | Natural Frequency (Hz) |
| 076.025.102 | 76 | 25 | 102 | 2.24 | 87 | 4.49 | 4.48 | 77 | 4.61 |
| 089.025.152 | 89 | 25 | 152 | 2.96 | 130 | 3.61 | 7.33 | 112 | 3.87 |
| 102.050.152 | 102 | 50 | 152 | 3.41 | 129 | 3.62 | 7.12 | 114 | 3.58 |
| 114.050.152 | 114 | 50 | 152 | 4.94 | 129 | 3.54 | 10.28 | 114 | 3.65 |
| 114.025.178 | 114 | 25 | 178 | 5.81 | 152 | 3.37 | 12.08 | 134 | 3.40 |
| 127.025.178 | 127 | 25 | 178 | 7.05 | 151 | 3.47 | 16.30 | 134 | 3.76 |
| 140.050.178 | 140 | 50 | 178 | 7.49 | 152 | 3.47 | 16.96 | 134 | 3.65 |
| 152.076.152 | 152 | 76 | 152 | 7.85 | 130 | 3.56 | 16.28 | 114 | 3.57 |
| 165.076.203 | 165 | 76 | 203 | 9.67 | 173 | 3.17 | 21.54 | 152 | 4.02 |
| 152.025.152 | 152 | 25 | 152 | 10.97 | 130 | 3.77 | 26.21 | 114 | 3.20 |
| 191.089.203 | 191 | 89 | 203 | 13.21 | 173 | 3.18 | 29.58 | 152 | 3.18 |
| 191.089.254 | 191 | 89 | 254 | 13.17 | 216 | 2.81 | 29.12 | 216 | 2.84 |
| 203.050.203 | 203 | 50 | 203 | 18.75 | 173 | 3.33 | 49.18 | 152 | 3.59 |
Load Requirements
Further sizes available. Email Us for details.
Donut Springs have a recommended working temperature range of -40°C to +75°.
