Heavy Load Straight Punches Lapping

This lapped heavy-load straight punch is used in precision blanking and punching stations where stable sliding motion and high contact loads are critical. In automotive and appliance sheet-metal dies, the straight shank and standard mounting geometry help maintain alignment across repeated strokes, reducing the risk of uneven wear.

For production cold-forming and multi-hit tooling, the lapped surface finish supports smoother punch travel under load, improving consistency in cutting edges and extending tool life by lowering friction at the guide interfaces.

When designing high-cycle parts such as electrical terminals, brackets, and connectors, select this variant to benefit from the lapped finish’s stability while keeping dimensional compatibility within the listed nominal diameter (4–25 mm) and length options (L: 40–120 mm). The combination of heavy-duty construction and lapped sliding surfaces makes it well-suited for long-running punch applications with demanding wear conditions.

The punch is offered in SKH51 equivalent powdered high-speed steel. Like common HSS families (often compared to AISI M2 class), SKH51 is selected for its ability to maintain hardness at elevated cutting temperatures and resist abrasive wear during high-cycle punching.

Key property trade-offs: high hardness and wear resistance improve dimensional stability of the punch tip, while toughness can be lower than more ductile tool steels—so proper guidance and alignment in the die are important to avoid chipping or edge fracture.

• Heat treatment: supplied as an engineered tool steel condition (exact state not specified in the provided data), typically provided after hardening and tempering for HSS performance.
• Surface finish: the lapped interface surface reduces sliding friction and promotes stable movement.
• Comparison: if alternative steels are used in the same category, HSS options like SKH51 generally favor wear resistance over softer steels, which may offer higher toughness but lower cutting/punching durability under load.

Start sizing by matching the punch’s nominal diameter to the die’s guide/clearance requirements. This series covers no. (nominal diameter) 4–25 mm, so choose the diameter that aligns with your punch guide bore and the intended clearance for stable centering.

Next, select the working geometry using the provided tip and length ranges. The P (tip dimension) is 3–20 mm and L (length) is available in 40–80 mm, 40–100 mm, and 40–120 mm options. Confirm the punch fully clears the stripper plate and has sufficient sticking length for your punch holder design.

• Full length alteration (LC): available ranges are 20–79.9 mm, 20–99.9 mm, and 20–119.9 mm; use LC when your tool layout requires adjustment of overall length while preserving the tip geometry.
• Tolerance/fit: ensure the selected diameter and mounting shape match the intended guided fit; lapped surfaces improve stability, but alignment still depends on die guide dimensions.