Ejector Leader Bushings - Oil Grooves SUJ2 Bearing Steel

Ejector leader bushings with oil grooves are used in injection molding and die-casting tooling to stabilize the straight motion of ejector pins, plates, and stroking components. This variant is well-suited for standard ejector assemblies where repeatable alignment and smooth start/return behavior are required.

• Automotive component molds: In high-cycle molding of housings, brackets, and connectors, the oil-groove feature helps retain lubricant at the guide interface, improving running stability and reducing galling risk during rapid actuation.
• Large die-casting molds: For ejector systems that see heavy sliding loads, the bearing-steel construction supports reliable guidance across long production runs.
• High-frequency short-cycle production: The lubrication-assisted design supports consistent ejector movement, helping maintain dimensional stability of the ejector train.

The SUJ2 bearing-steel base material is chosen to balance wear resistance with the toughness needed for repeated ejector operation.

This ejector leader bushing is manufactured from SUJ2 bearing steel, a high-carbon chromium bearing alloy widely used for guide and wear surfaces. SUJ2 is commonly treated to achieve high surface hardness for resistance to fretting and abrasive wear in sliding applications.

• Typical property intent: high hardness at the working surfaces for long guide life, with toughness retained to resist chipping under load reversals.
• Heat treatment state: SUJ2 guide components are generally supplied in a quenched and tempered condition (or equivalent heat-treated state) to reach the required hardness and dimensional stability.
• Wear vs. toughness trade-off: increasing hardness improves wear resistance but can reduce impact tolerance; the selected bearing steel treatment targets balanced performance for ejector guiding.

No alternative steel grades are specified for this part; if your application targets extreme impact, consult the supplier for material/process variants beyond the SUJ2 configuration.

Correct selection is primarily based on the bushing inner diameter d = 8 ~ 50 mm and the shaft-guiding section length ℓ (Dh6) = 10, 13, 15, 20, 25, 30 mm. In a mold, match d to the ejector pin or leader shaft diameter that the bushing guides, and match ℓ to the required bearing/guide length for stable alignment.

• Step 1 (fit to shaft): Select the bushing size where the inner diameter d corresponds to the leader shaft diameter used in your ejector assembly.
• Step 2 (support length): Choose ℓ from the available values to cover the effective guide zone needed to prevent misalignment at stroke speeds.
• Tolerance/fit: The Dh6 designation indicates a controlled diameter tolerance class; ensure the shaft and bushing fit is compatible with your intended clearance to maintain stable guiding and oil retention.

If your cavity/core layout limits guide travel length, prioritize selecting the closest available ℓ while maintaining adequate engagement length across the operating stroke.