JIS Standard SKH51 Steel Straight Punches Flat Head

Straight punches with flat head are used inside progressive or transfer die sets to drive consistent blanking and piercing. The flat-head tip geometry helps distribute forming load during each stroke, supporting stable penetration when the punch works with matching die openings.

• Automotive and appliance stamping: ideal for repeated steel or sheet-metal operations where straight shank guidance improves alignment and helps maintain consistent hole size across production cycles.
• Electronics and connector housings: suited for making precise locating features (tabs, mounting holes, and small openings) in thin gauge parts, where close clearance tooling benefits dimensional repeatability.
• General manufacturing dies: the fixed head type supports predictable engagement, reducing variation in piercing quality under cyclic loads.

This SKH51-based variant is well-suited for these applications because it is a hardened wear-resistant tool steel (JIS SKH51, described as equivalent to M2) that can better tolerate abrasive wear during high-frequency punching.

JIS Standard SKH51 steel is specified for this punch. It is commonly regarded as an AISI M2 equivalent, targeting high hot-hardness for tooling and strong resistance to abrasive wear in metal forming operations.

• Hardness / wear vs. toughness: hardened tool steel like SKH51 is selected to maximize edge retention during blanking and piercing; this typically trades off some impact toughness compared with lower-alloy, softer steels.
• Heat treatment state: the tool is provided in a hardened steel construction suitable for production runs, which helps resist wear at the punch tip under repeated cycles.
• Manufacturing process: typically produced via precision machining of the straight shank and tip, followed by heat treatment to achieve the working hardness and stable dimensional performance.

If you compare alternatives, higher toughness steels may reduce chipping risk but often sacrifice wear life at the cutting edge—making SKH51 favorable where maintaining tip sharpness is critical.

Select dimensions to ensure correct projection and engagement between the punch and mating die opening in the die set. This series provides a variable tip dimension P (1–3 mm) and fixed L (25–50 mm) plus LC (25–50 mm), which should be chosen to match your cavity/core layout and required working stroke geometry.

• Match the piercing/blanking feature size: set P according to the desired tip profile and the required hole/channel dimensions in the punched part.
• Confirm alignment and guidance length: use L (25–50 mm) to ensure sufficient straight-shank engagement within the guide components, improving repeatable positioning.
• Verify full length alteration (LC): choose LC (25–50 mm) to align with your die set spacing, holder stack-up, and clearance strategy.

Because the series includes fixed ranges for L and LC, keep tooling drawings consistent with the die’s cavity/core thickness and the required clearance. Follow your supplier’s standard tolerance for punch-to-die clearance to prevent edge chipping or burr formation.