Lee Spring, a leading global manufacturer of mechanical springs since 1918, introduces LeeP™ plastic composite springs, which are molded from SABIC Innovative Plastics’ Ultem* resin. These springs are among the first springs made with engineered plastic, which gives them several advantages over traditional metal alloy springs. Ultem resin gives the new springs a range of properties including high strength-to-weight ratio, no magnetic interference, high corrosion resistance, and dielectric insulation for non-conductive applications.
“Thermoplastics have rarely before been used in high-performance springs, so we were venturing into uncharted territory with Lee Spring,” said Shawn Lee, product marketing manager, SABIC Innovative Plastics. SABIC conducted predictive analysis, material characterization and mold optimization for this project.
Lee Spring saw an untapped opportunity to expand its market reach with high-performance thermoplastic springs that approach the strength of metal without certain drawbacks. According to Steve Kempf, CEO of Lee Spring, “Our customers’ wish list includes strength, heat stability, corrosion resistance, non-magnetic properties, insulation, inertness, low flame toxicity and recyclability. What led us to Ultem resin was its excellent all-around performance combined with great strength.”
For example, in marine applications, LeeP springs made with Ultem resin offer longer life due to resistance to salt water. For the medical device industry, LeeP springs avoid the cost of shielding, which is necessary for metal springs but can interfere with diagnostic imaging. Other market sectors that may benefit from the new springs are: medical products and processing equipment, pharmaceutical delivery devices, food processing and packaging equipment, aerospace products, electronics and electrical equipment, water purification systems and automotive interiors.
LeeP Plastic Composite Springs are stocked in a variety of standard sizes, each available in a “rainbow” of strengths formulated from Ultem resin containing various levels of fiber reinforcement.
Robust Performance and Much More
Spring rate (a function of shear modulus), cycle life (resistance to fatigue) and creep resistance are key performance measures for these compression springs. Ultem resin not only provides excellent results for these criteria, but also delivers other key properties:
•Mechanical stability up to 170 C, allowing for use in a wide range of environments.
•High strength-to-weight ratio: Ultem resin is the highest strength amorphous resin in the market.
•High corrosion resistance and generally compatible with many chemicals including strong acids, weak bases, aromatics, and ketones.
•Non-magnetic to avoid interference with imaging and other Ferro-sensitive technologies.
•Dielectric insulating material suitable for non-conductive applications.
•Inert non-contaminating plastic composite protects product purity.
•Low flammability and toxicity ensure environmental safety.
•Recyclable and compliant with most global regulations including RoHS and REACH.
SABIC Innovative Plastics
Lee Spring Company LLC