Polyurethane Compression Springs
Custom urethane springs for compression and tooling applications
Develop a polyurethane spring around the force and movement your assembly requires. Send Willsup the free height, available space, working stroke and loading conditions to discuss a custom compression element or replacement urethane die spring.
Request a quote for this partTechnical specifications
- Construction
- Elastomer compression element
- Geometry
- Cylindrical, annular or custom, subject to review
- Force and stroke
- Defined for the assembly
- Hardness
- Selected with the formulation
- Duty cycle
- Required input for design review
- Manufacturing
- Pointe-Claire, Quebec
How a polyurethane spring works
An elastomer spring deforms under compression and recovers as the load is removed. Its response depends on the compound, geometry and restraint in the assembly. A hardness value is not a spring rate, and replacing a steel spring requires more than matching the original outside dimensions.
Specify the force required over the working stroke, including preload and maximum compression. Where the response is critical, the project needs an agreed load-deflection test rather than an assumed rating.
Urethane die springs and punch stripping applications
In tooling, a compression element may provide return force or assist stripping after an operation. Send the die assembly information, guide clearance, travel limits and cycle rate. The design review must establish room for deformation, the contact arrangement and the required force throughout the stroke.
Existing spring dimensions, colour or nominal hardness do not prove interchangeability. Identify the original specification and the failure you are trying to address before selecting a replacement.
Information needed for a compression spring review
| Requirement | Details to provide |
|---|---|
| Envelope | Free height, OD, bore and assembly drawing |
| Working stroke | Preload, normal travel and maximum travel |
| Force | Required force at specified displacements |
| Cycling | Cycles per minute, dwell and operating hours |
| Environment | Temperature, lubricants and other exposures |
Validate the spring in its operating conditions
Repeated compression and sustained loading are different service conditions. Provide the complete cycle, including pauses and holding periods, to help define the validation plan. Record force, displacement and relevant operating conditions when evaluating a sample. The acceptable working range must be established for the component rather than copied from another product.
Spring, bumper or tube?
A spring is selected around its force-displacement function. A bumper is selected around a stopping or contact event. For equipment stops, see urethane bumpers. If you need an unqualified tubular blank for further manufacturing, see cast polyurethane tubes.
Your project with Willsup
Our manufacturing capabilities in Pointe-Claire bring together mold design, polyurethane casting and finish machining. Send your drawing or sample with the service conditions so we can review feasibility, material requirements and the manufacturing approach before confirming a quotation.
Applications to discuss
- Tooling compression elements
- Die return applications
- Punch stripping projects
- Custom preload elements
Custom manufacturing with Willsup
- Start from a drawing or sample
- Formulation selected for service conditions
- In-house mold design
- Casting and finishing to project requirements
- Manufacturing in Pointe-Claire, Quebec
- Quantity and schedule confirmed with your quote
Common questions
-
Can polyurethane replace my steel die spring?
Possibly, after review of the required force, stroke, available space and duty cycle. Matching external dimensions alone does not establish an equivalent replacement. -
What compression percentage is allowed?
There is no universal value for every urethane spring. The working range must be specified for the compound, geometry, restraint and cycling conditions. -
Can you provide load-deflection data?
Include the required measurement conditions and acceptance criteria in your enquiry. Testing scope and data requirements must be agreed for the project. -
Do spring colours identify their load rating?
Do not assume colour codes transfer between suppliers. Use the actual material and component specification to identify performance.
Ready to spec your part?
Tell us your load, size, and operating conditions and we will recommend the right formulation.
Request a quote for this part