Light Load Round Wire Die Spring - 40% Deflection

This light-duty die spring is used inside inch-system die assemblies where you need controlled return force without overloading the die set during repeated cycling. It’s especially suited to progressive and stamping dies that demand stable part ejection/stripper return over many strokes, benefiting from a consistent 40% allowable deflection ratio.

In automotive connector and terminal stamping lines, the spring’s round-wire geometry helps provide predictable spring response as the press cycles, reducing variability that can affect feeding and formed feature accuracy.

• Progressive/stamping die return: tuned for light load with controlled travel (40% deflection allowance).
• Inch die setups: built for inch-system fit using specified outer diameter options (3/8", 1/2", 5/8").

Its chrome-silicon construction supports reliable die return under wear conditions typical of high-cycle tooling.

The spring is described as a chrome-silicon style spring steel intended for dependable wear resistance and stable return force in die tooling. Chrome-silicon steels are commonly selected for springs because they can maintain elasticity under cyclic loading better than plain carbon spring steels.

• Expected property focus: improved fatigue resistance and wear durability for die return applications.
• Hardness/heat treatment: no specific HRC value or heat-treatment state is provided in the available data, so hardness should be verified from the manufacturer’s material certificate for your lot.
• Trade-off: increased alloying typically improves fatigue/wear performance, but spring steel still requires careful heat treatment to balance toughness and allowable deflection.

For close design control, confirm the exact chrome-silicon specification and heat-treatment process used by the supplier, since these details directly affect fatigue life at the selected deflection level.

Correct sizing begins with matching the die assembly’s required travel and installing dimensions. This spring is specified with an outer diameter D of 3/8", 1/2", or 5/8" and an available length L range of 1 to 12 inches.

To select the right variant, choose:

• D (outer diameter): match the spring pocket/guide clearance in your inch die set using 3/8", 1/2", or 5/8".
• d (inner diameter): verify the listed inner diameter options of 3/16", 9/32", or 11/32" are compatible with the surrounding guide/center elements.
• L (length): pick the closest available length within 1–12 in to achieve the required installed stack height and working deflection.

Design around the stated 40% allowable deflection ratio: the working deflection should not exceed 40% of the spring’s rated deflection capability to maintain return reliability and avoid premature fatigue. If your die pocket uses tight clearances, account for manufacturing tolerances on D, d, and L during fit-up.