TF/TL/TM/TH/TB Heavy Duty Load Compression Spring Die Springs OD:12mm L:20-80mm

Match the load grade to the force your tooling requires at working deflection. Yellow (TF) is Extra Light — suitable for light stripper plates or ejector return. Blue (TL) is Light. Red (TM) is Medium — the most common general-purpose grade. Green (TH) is Heavy, and Brown (TB) is Extra Heavy for high-tonnage dies. If you know the required spring force at a specific deflection, use the load-deflection chart for the selected grade and length to confirm the match.

Measure the depth of your spring pocket and the required working stroke. The free length should be long enough so that at maximum working deflection the spring does not reach solid height. A common rule of thumb: free length = working stroke ÷ (max deflection ratio for the grade). For most grades, do not exceed 30–45% deflection of free length to maintain fatigue life.

Yes. The outer diameter of 12 mm and the length increments conform to ISO 10243 and JIS B 5012 dimensional standards. They are designed as drop-in replacements for any tooling built to these specifications. Always verify the pocket bore diameter matches the OD and that the pocket depth accommodates the free length you select.

When operated within the recommended deflection range (typically ≤30% of free length for Extra Heavy grades, up to ~45% for Extra Light grades), die springs of this type are generally rated for 500,000 or more press cycles. Exceeding the recommended deflection significantly reduces fatigue life. Replace springs showing visible set (permanent shortening of free length) or surface cracking.

These springs are made from alloy steel and are not inherently corrosion-resistant. For mildly humid environments, applying a light machine oil coating during storage and use is recommended. For highly corrosive or elevated-temperature environments (above approximately 150°C / 300°F), consider stainless steel or high-temperature alloy die springs instead. Contact us to confirm suitability for your specific conditions.

Order 1 piece for a single replacement or prototype evaluation. Order 2 pieces when your die uses a symmetric pair of springs (common in two-post stripper plate designs). Order 5 pieces when outfitting a multi-spring die set or when you want to keep spares on hand to minimize downtime during production runs. Buying in packs of 5 typically offers a lower per-unit cost.

Die springs use a rectangular (flat) wire cross-section rather than round wire. This allows more material to be packed into the same outer diameter, resulting in higher load capacity and energy storage per unit volume. They are also manufactured to tighter dimensional tolerances and fatigue-rated for cyclic press applications — standard coil springs are not designed for this duty cycle.