JIS Standard Steel One-Step Core Pins

One-step core pins are used in precision injection mold tooling where the core must be located and supported through a single, direct engagement feature—without a second locating step. This makes the pin effective for compact core systems that require repeatable alignment during closing, ejection support, and long production runs.

• Automotive connector and insert molding: Use in multi-cavity tooling to stabilize core positioning while the hardened steel resists wear at the contact surface. The optional TiCN coating improves surface durability under frequent cycles.
• Consumer electronics housings: Suitable for stepped round cores that need consistent ejection support and reduced assembly variance. The selectable shaft diameter tolerances (e.g., 1–16.5 mm D/P) help match tighter fit requirements.
• Medical device component cores: Helps maintain dimensional stability in molds with smaller, high-precision locating areas. Use the pin variant with controlled L dimension tolerance (+0.02/0) when core engagement length is critical.

These one-step core pins are made from SKD61 or SKH51 hardened steel, selected to balance wear resistance and toughness for mold core locating applications. SKD61 is commonly specified for hot-work die steels (often treated to achieve high hardness), while SKH51 is a high-speed steel variant (often used when abrasion resistance at the contact zone is critical).

• Surface treatment: Available as No treatment or with TiCN coating, which increases surface hardness and improves wear resistance under repetitive contact.
• Hardness & trade-offs: Higher hardness improves wear life, but can reduce toughness if not properly heat treated; selecting SKD61 vs. SKH51 supports the required performance balance for the core’s duty cycle.
• Heat treatment state: Pins are provided as hardened steel, intended for stable fit after machining and assembly.

Note: Specific HRC values are not provided in the supplied data.

To select the correct stepped one-step core pin, match both the shaft diameter and the engagement length (L) to your core/core-cavity locating geometry. The available D/P (shaft diameter) range is 1 ~ 16.5 mm (and nominal diameter 3 ~ 25 mm, depending on configuration), so choose the diameter that fits the mating bore in your mold.

• Engagement length: Select the L dimension from 20 ~ 120 mm (or 30 ~ 120 mm in certain ranges). Use the tolerance option +0.02/0 when you need precise core pin engagement without clearance growth.
• Fit and tolerance: Shaft diameter tolerances are available as -0.01/-0.02 or 0/-0.005. Use the tighter negative tolerance when you require consistent clearance, and the near-zero option when you need close fit stability.
• Geometry compatibility: Choose the first step shape (1A~1E) and the tip shape (No processing, B, C, G, R, T) that match your core lead-in and ejection support requirements.

Confirm the fixed RE (0.5 ~ 2 mm) and K (21 ~ 60°) values align with the stepped profile in your mold drawing.