SKD61 Steel Taperless One-Step Center Pins

Taperless one-step center pins are used in injection mold tooling wherever stable, repeatable part registration is required—especially in multi-up assemblies and precision machining setups. Their taperless, one-step geometry supports consistent alignment during mold/tool positioning, reducing settling that can shift workpiece location.

• Automotive connector and bracket molds: Use these pins to maintain register between cavity inserts and ejector-side tooling, supporting repeatable assembly when high cycle rates demand long-term positional stability.
• Medical device housing molds: The nitrided SKD61 surface improves wear resistance at the locating interface, helping preserve alignment through repeated clamp-open cycles where dimensional control is critical.
• Electronics enclosure tooling: Configurable lengths (L ranges up to 700 mm depending on variant) help match different stack heights, enabling correct engagement with mating sleeves without excessive interference.

The ground shaft diameter with the specified tolerance is well-suited for precision locating fits to sleeves, supporting reliable repeatability across production runs.

The pins are manufactured from SKD61 steel, a hot-work tool steel commonly aligned with H13 (AISI equivalent) in performance class. SKD61 provides a practical balance of toughness and hot/dynamic wear resistance for tooling components subjected to repeated loading.

• Nitrided surface treatment: A nitrided layer increases surface hardness and wear resistance at the locating contact area, helping maintain dimensional stability over time.
• Hardness & trade-offs: Nitriding improves wear resistance, but the core toughness still governs impact and bending resilience; adequate strength is required to avoid deformation in tight alignment stacks.
• Manufacturing approach: Ground shaft finishing supports the specified fit tolerance for sleeve engagement, while the one-step taperless form minimizes geometric variability during tool alignment.

If compared to non-nitrided variants, the nitrided surface typically offers improved wear life at the locating interface, at the expense of additional surface-processing steps.

Select the center pin dimensions by matching the shaft diameter and locating features to the mating sleeve/core registration requirements. The shaft diameter D/P is available in 1.5 ~ 16 mm, and the design-fit is controlled by a fixed shaft diameter tolerance of -0.01/-0.02—use this when you define clearance/press-fit with the sleeve.

• Choose D/P first: Pick the shaft diameter within 1.5 ~ 16 mm that matches the sleeve bore specification; account for the negative tolerance to avoid overly tight engagement.
• Verify engagement length: The length dimension L is offered in multiple ranges depending on configuration (e.g., 70 ~ 500, 70 ~ 700, 70 ~ 200, 70 ~ 400).
• Select head thickness: Head thickness options are 6 mm (JIS), 8 mm (JIS), or 4 mm (T4), which should align with your stack-up to control seating height.

The step shape (B/C/D/E) and tip shape (e.g., No processing, B, C, G, R, T) affect how the pin interfaces with the mating part; select the variant that matches the required step geometry and tip engagement depth.