SKH51 Steel Gas Release Round Core Pins

These gas release round core pins are used in injection mold tooling when the cavity includes a boss or raised feature that also requires reliable venting. The built-in gas vent hole design supports faster exhaust of trapped air and volatiles, helping reduce gas-related defects while maintaining stable core placement.

• Automotive connector and housing molds: ideal for small, repeatable bosses where consistent venting helps prevent short shots and surface burn marks around the boss.
• Consumer electronics enclosures: suited for thin-wall parts with localized features; the round core profile supports controlled positioning while the vent hole improves mold breathing.
• General-purpose precision core tooling: the multiple hole shape types (CG/CS/RG/SG/SS) allow engineers to match exhaust geometry to gate/flow patterns for steady support.

For these applications, the SKH51 steel variant provides wear resistance needed for repeated cycling, especially where vented cores experience friction during assembly and demolding.

SKH51 steel is a high-performance tool steel (commonly compared to AISI M2 in wear/cutting tool applications). It is typically supplied in a heat-treated condition with quenched and tempered hardening to balance hardness and toughness for core pin service.

• Hardness: designed for high wear resistance; the quenched & tempered hardening state provides stable hardness under intermittent loading.
• Wear resistance vs. toughness: as hardness increases, the component generally becomes less tolerant of severe shock. For core pins that see steady demolding loads and vent-related friction, this trade-off is beneficial.

Compared with softer structural tool steels, SKH51’s higher hardness supports longer life in sliding and repetitive core operations. Compared with more specialized nitriding-focused grades, SKH51’s through-hardening condition can be advantageous when you need reliable hardness without relying solely on surface-only treatments.

Select the pin geometry by matching the boss/core feature in the mold cavity to the pin’s nominal and functional dimensions. Start with D/P (shaft diameter) in the range 2.5–6 mm and choose the No. (nominal diameter) from 3–6 mm to ensure the pin fits the guide/boss bore system used by your core tooling.

• Hole diameter (A): fixed at 1.5 mm for the gas vent function.
• Hole depth (B): fixed at 0.5–4 mm depending on the selected pin length variant.
• Chamfer: fixed C = 0.2–0.5 mm and G = 0.25–1 mm—confirm these match the vent-hole entry/relief requirements.
• Length (L): variable across options such as 10–60 mm, 11.5–60 mm, 12.5–60 mm, 13.5–60 mm, or 14.5–60 mm.

For fit, use the available hole tolerance options: 0/-0.02 or 0/-0.01 to control clearance and prevent wobble during support. If you must align exhaust timing precisely, also select the hole shape type (CG/CS/RG/SG/SS) appropriate to your vent path geometry.