Formathane Urethane Springs (Inch) Low Repulsion

Formathane urethane springs are used inside injection mold tooling where springs must control shock, return force, and vibration during frequent cycling. They are well-suited for systems that experience changing loads because the low repulsion urethane formulation helps maintain a stable spring response over time.

• Automotive connector and electrical housing molds: In tooling for multi-cavity parts with frequent ejector actuation, select the urethane type matched to load (e.g., PO-650 red for medium loads) to support consistent shock absorption and reduce maintenance from wear.
• Appliance and consumer product molds: For components requiring smooth ejection and reliable force return, use low-to-medium load options (e.g., PO-670 black for very low load) when light-duty springs are needed to maintain repeatable behavior.
• Industrial housings with heavier duty cycles: When higher loads are expected, PO-652 tan (very high load) supports dependable performance while retaining elasticity for long service life.

This series uses Formathane urethane springs rather than steel. The key material differentiator is the urethane type, each tuned for a specific load/response range: PO-670 (very low load, black), PO-650 (medium load, red), CU-290 (high load, yellow), and PO-652 (very high load, tan).

• Properties: Urethane provides high damping and reliable shock absorption, with stable elasticity suited for light to heavy duties.
• Heat treatment: No steel quench-and-temper step is applicable; performance is governed by the urethane formulation and spring geometry.
• Wear/repulsion trade-off: Low repulsion variants are intended to reduce bounce and improve smooth force return, improving durability under cycling.

Because these are urethane components, hardness is not specified in HRC; design selection should be based on the provided load-specific urethane types and dimensional limits.

Select the Formathane urethane spring by matching the length (L), outside diameter, and inner diameter (d) to the mold’s spring cavity, guide features, and required stack-up. The available ranges for this series are: L = 1 ~ 24 in, Outside Dia. = 0.6875 ~ 1.75 in, and d = 0.1875 ~ 1 in.

• Step 1: Fit in the housing: Confirm the spring’s outside diameter fits the surrounding bore/seat with the needed clearance for assembly and motion.
• Step 2: Centering on the core/rod: Verify the inner diameter (d) matches the guiding shaft or post dimension, ensuring stable alignment during compression.
• Step 3: Achieve the correct travel/working length: Choose L to align with the intended compression stroke without coil bind or excessive solid height.

Urethane type selection (PO-670 black, PO-650 red, CU-290 yellow, PO-652 tan) is configurable for load performance, while the physical dimensions are constrained to the stated inch ranges.