Heavy Load Straight Punches Lapping

Heavy-load straight punches are used in injection press tooling where consistent penetration and clean forming are required under high mechanical stress. Their straight shank and standard mounting geometry help maintain repeatable alignment, reducing variation in punch-to-die engagement during production.

Common scenarios include industrial connector and terminal cutting where thick or work-hardened sheet stock demands stable load-bearing performance. The lapping-finished contact surfaces support reliable forming contact, helping minimize localized wear and variation in part dimensions.

They are also suitable for appliance and automotive bracket punching, particularly when cyclic loads can magnify alignment drift. Powdered high-speed steel options (SKH51 equivalent) are selected for improved wear resistance, supporting longer tooling life compared with more basic tool steels.

• Choose for high-stress blanking/cutting operations requiring stable alignment
• Use where punch-to-die engagement accuracy must remain consistent over cycles
• Powdered high-speed steel supports wear durability in abrasive or hard materials

This series is offered with SKH51-equivalent high-speed steel options, including powdered high-speed steel. SKH51 is commonly treated as an AISI M2 equivalent in terms of tool-class performance, giving a balance of hot hardness and wear resistance for punching applications.

• Powdered HSS (if selected): refined microstructure for improved wear resistance and more uniform hardness distribution
• Conventional SKH51-equivalent: good toughness, but typically less wear consistency than powdered grades

For lapping punches, hardness and toughness trade-offs depend on the heat treatment target. Typically these tool steels are supplied in a quenched & tempered condition to achieve punching-ready hardness, with subsequent finishing to control surface integrity. Expect higher hardness for improved wear resistance, while too high a hardness setting can reduce toughness under shock loading.

Select the punch size by matching the nominal diameter and tip dimension (P) to the mold/press geometry, then confirm the available shank length (L) and full length alteration (LC) against your holder and die setup.

• No. (nominal diameter): 4 ~ 25 mm
• P (tip dimension): 3 ~ 20 mm
• L (length): 40 ~ 80 / 40 ~ 100 / 40 ~ 120 mm (order the specific range available for your configuration)
• LC (full length alteration): 20 ~ 80 / 20 ~ 100 / 20 ~ 120 mm (must align with the alteration/adjustment requirement in your tooling design)

Use the chosen No. to set punch clearance and guide fit within the punch holder, and use P to control the functional cutting/forming profile. Verify that L provides sufficient engagement without bottoming in the holder, and that LC supports your expected adjustment while maintaining alignment. If your press system requires tight fit, ensure that the selected diameter matches the holder bore specification to avoid excessive radial play.