Tapered Head Ejector Punches

Tapered-head ejector punches are used inside injection mold tooling where controlled stripping force is needed to keep ejection alignment stable during high-cycle operation. The tapered head helps transfer force predictably from the ejector system to the molded part, reducing the risk of uneven contact during release.

In automotive connector and sensor housing molds, this punch style supports repeatable ejection alignment under heavy-load punching conditions, which is important when parts have deep ribs or tight undercuts. The single-stepped shank and tapered head mounting geometry help maintain concentricity, improving stripping consistency over long runs.

For industrial appliance and electronic enclosure molds, the controlled tip shape is suited to stable part release from hardened-core or punch-die cavities. Engineers typically select the SKH51-equivalent variant for its wear-resistant behavior in ejector regions that experience frequent micro-impact and rubbing.

• Heavy-load punching ejection for dependable part release
• Tapered head mounting and single-stepped shank for alignment stability
• Controlled tip shape for predictable stripping force transfer

This variant uses SKH51-equivalent powdered high-speed steel, selected for punch work where abrasion and sliding wear are dominant. Powder metallurgy processing improves micro-uniformity, supporting consistent carbide distribution for reliable wear resistance at the ejector tip and working surfaces.

• Material grade intent: SKH51 is typically treated as an AISI M2-equivalent high-speed steel family.
• Heat treatment (typical for this class): quench and temper to achieve a practical balance of hardness and toughness for ejector use.

Hardness: exact HRC is not provided in the supplied specifications, so final hardness should be confirmed from the manufacturing certificate or the MISUMI lot data. In general, higher hardness increases wear resistance but can reduce toughness under shock loads; heavy-load punching applications benefit from tempered toughness to limit chipping at the tapered head.

If alternatives are available (e.g., more abrasion-focused grades vs. higher-toughness HSS), choose based on whether your ejector failure risk is wear (tip rounding) or impact chipping (micro-stresses during ejection).

Selection is driven by matching your ejector working projection and fit into the mold’s punch/ejector system. Use the provided dimension ranges to map the ejector location, stroke clearance, and tip reach to the cavity/core geometry.

• Shank diameter D (mm): choose 8, 10, 13, or 16 to match the ejector bore or guided support in your tool design.
• Tip length/geometry B: select the available L, S option corresponding to your required tapered head engagement depth.
• Tip dimension P (mm): match to the molded undercut/release contact zone using the ranges 4–7.99, 5–9.99, 6–12.99, or 10–15.99.
• Overall L (mm): pick from 50–80, 55–90, 60–80, 60–90, 65–100, or 70–100 depending on required projection and housing thickness.

For reliable stripping, confirm clearance around the tapered head to avoid rubbing while ensuring sufficient contact. Tolerance/fit details are not specified here; therefore, validate bore tolerances and any guiding diameter requirements against your mold plate/ejector components before finalizing D and overall L.