Why use a Composite Spring?
- Reduce operating costs by limiting failures caused by traditional materials
- Will not scratch sealing surface or mark-off steel surface during service
- Will not corrode like steel
- Composites drill out easier than steel, not nesting in the drill bit
How do composites compare to metal springs?
Extrusion resistance is comparable to steel springs, sometimes better. Continuous Carbon Fiber composite tape modulus, in the fiber direction, is about 2/3 that of steel. Tensile strength of tape in the fiber direction is 300KSI (~2000 MPa). Given geometry constraints and surrounding by rubber, the spring need not act exactly like steel and can be designed with fewer gaps for rubber to extrude through.
Design and Molding options.
For molding, some customers use a bonding agent, others do not. Springs’ gap can range from zero to several times the width of the material. Most customers experiment with springs of varying gaps to optimize their molding process.
Springs are often made from continuous carbon fiber reinforced PEEK composite. Steel springs, O-ring cord, or PEEK monofilament may be inserted to prevent collapse during molding. Use of nested steel springs allows for higher overall stiffness of steel, with scratch-protection of composites on the exterior.
Lastly, we can eliminate the need for end connectors by simply intertwining the helix at each end, creating complete circles with the springs.
Automated Dynamics’ Approach
We recommend ordering a small initial quantity for molding trials. Our engineers aid in the design process of the springs and are available for consultation before and after testing. We have extensive experience in molding these springs for our clients around the world.
For more information on composite springs, contact:
Business Development Manager – Oil & Energy