JIS Standard Precision One-Step Core Pins T4 Head

These precision one-step core pins are used to support and locate cores in injection mold assemblies where repeatable seating and stable alignment are required. The T4 head provides a positive, one-step interface that helps maintain core position through repeated closing cycles, reducing the risk of drift caused by partial seating.

• Automotive connector and terminal molds: Apply for multi-cavity tooling where controlled shaft/tip gradient tolerances help ensure consistent core-to-cavity alignment during high-cycle production.
• Electronic housings and small-part molds: The compact stepped geometry and stable head seating support precise part features while enabling straightforward assembly engagement.
• Medical device housing inserts: Use the SKH51 or SKD61 variant to balance dimensional stability and wear resistance for long runs where consistent core placement is critical.

Choose this variant when your design relies on one-step seating accuracy (no second step engagement) and precise tip geometry to preserve alignment over time.

Material options are SKH51 or SKD61, both selected for mold tooling wear resistance and dimensional stability. SKH51 is a high-speed steel grade (commonly associated with AISI M2 class performance) that is typically chosen when higher wear resistance is needed. SKD61 is a chromium-molybdenum hot-work die steel (commonly associated with H13 class performance), often selected for a balanced toughness-to-wear profile in injection tooling.

• Heat treatment state: Supplied as a hardened, precision core pin suitable for tooling service; final HRC targets depend on the selected grade and manufacturer heat cycle.
• Hardness & trade-offs: Higher hardenability and wear resistance generally improve tip life, while the toughness balance differs by grade (SKD61 typically prioritizes toughness stability; SKH51 can emphasize wear performance).
• Manufacturing: Ground/finished shaft and tip profiles are controlled to achieve the stated tight tolerances, supporting reliable one-step seating and alignment.

When selecting between grades, base the choice on whether your dominant risk is tip wear (favor SKH51) or toughness under thermal/mechanical cycling (favor SKD61).

To select the correct one-step core pin, match the shaft diameter and overall length to your core support bore and core placement requirements. The shaft diameter range is D/P = 1 ~ 20 mm, and the L dimension range is L = 6.5 ~ 7 mm. Use the specified step geometry to ensure proper one-step seating: choose the First Step Shape (1A ~ 1E), then select the A step diameter (0.4 ~ 5 mm), and the taper/step parameters (for example CVC = 0.1 ~ 1 mm increments and C taper width options).

• Head seating: The T4 head design provides the one-step interface; ensure your core support stack-up allows full head engagement without interference.
• Tip profile: Select the Tip Shape (No processing, B, C, G, R, T) and the associated tip dimensions (e.g., K = 21 ~ 60° depending on option, Q = 0.2, S = 0.1).
• Tolerance/fit: L dimension tolerance is +0.01/0, 0/-0.1. When mating to the mold body, account for this tolerance stack so the pin seats consistently without excessive clearance.