SKD61 Steel Nitrided Straight Ejector Sleeves Head T4

Used in injection mold tooling as a straight-line ejector sleeve to guide the movement of ejector components and help maintain concentric alignment under repeated cycles.

In automotive connector and housing molds, the nitrided SKD61 base supports stable ejection travel while the Head T4 geometry promotes consistent sleeve positioning, reducing the risk of sticking or side-load wear on mating ejectors.

In appliance and industrial part molding, the H7 inner diameter tolerance variant is suited for controlled fit stability, supporting repeatable clearance over production runs with temperature cycling and abrasive contamination.

For die casting tooling assemblies where guided ejection is critical, the combination of a straight sleeve design and wear-focused surface treatment helps maintain functional guidance and dimensional repeatability.

• Choose this component where guided, straight ejector motion and bore stability are required.
• Head T4 is intended to improve alignment stability during operation.
• H7 bore tolerance supports controlled clearance for reliable ejection guidance.

This variant is made from SKD61 steel and delivered in a nitrided condition. SKD61 is commonly treated as an H13-equivalent hot-work die steel in performance discussions due to its balance of hot strength, toughness, and machinability.

Nitriding creates a hardened surface layer that improves wear resistance and surface durability at the bore, which is critical for guided ejection where friction and sliding contact occur.

• Hardness (typical expectation): nitrided SKD61 generally targets a significantly higher surface hardness than the core; exact HRC is dependent on the nitriding parameters and is set by the manufacturing process.
• Trade-off: nitriding increases surface hardness and wear life, while maintaining a tough core to reduce chipping risk under shock loading.
• Manufacturing: steel is machined to final dimensions, then nitrided to harden the contact surfaces; post-process performance relies on controlled bore/fit.

Compared with un-nitrided SKD61, the nitrided surface offers better sliding wear performance for sleeve-to-ejector guided motion.

Selection starts by matching the sleeve’s D/P (shaft diameter) to the ejector shaft that runs inside the sleeve. The available shaft diameter range is 3.5 ~ 10 mm, with shaft diameter selection increments of 0.01 mm, enabling close-fit engineering.

Next, match the V (hole diameter) to the interfacing geometry. Available V ranges are 1.5 ~ 2.5 mm, and the S (V hole diameter length) is selectable in 20 ~ 50 mm or 20 ~ 40 mm depending on the configuration.

Choose overall length L based on mold layout and stack-up. Options include 40 ~ 200 mm, 40 ~ 250 mm, and 40 ~ 300 mm.

• Confirm C (recess diameter) in the 2 ~ 3 mm range for the required head/recess fit.
• The inner diameter is specified with H7 tolerance; use an H7 bore assumption when calculating clearance versus the mating shaft’s tolerance.
• Maintain compatibility with the straight-line ejection requirement of your core/cavity design.