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SKD61 Precision Mold Ejector Pins & Core Inserts
Ejector pins, stepped core pins, sleeve pins and flat ejector bars are precision machined from premium SKD61 hot work tool steel, delivering outstanding high-temperature hardness, thermal fatigue resistance and wear resistance. These mold core components guarantee stable ejection, consistent dimensional accuracy and extended service life for high-volume precision injection molding and die casting.
- Material: SKD61 Hot Work Tool Steel
- Hardness: HRC 48–52 after full heat treatment
- Tolerance: ±0.001 mm
- Surface Finish: Ultra-fine ground
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High-Precision Engineering
All ejector components are processed with high-rigidity Japanese & Taiwanese grinding equipment, ensuring perfect straightness, concentricity and tip flatness. Stepped and multi-stage core pins feature seamless transition shoulders to eliminate stress concentration during repeated ejection strokes.
This enables smooth, scratch-free demolding of delicate micro inner structures, thin walls and tiny feature geometries without product deformation.
Heat-Treated SKD61 Steel Construction
Made from premium SKD61 hot work tool steel, these mold pins deliver key performance strengths:
- Superior thermal shock & fatigue resistance under continuous high mold temperature
- Stable hardness with minimal thermal expansion
- Excellent anti-wear performance for millions of ejection cycles
- Strong impact toughness to resist bending or breakage in thin, slender pin designs Perfect for high-cycle injection and die casting molds where heat stability and durability are essential.
Optimized for Complex Mold Forming
This full range of ejector pins and core inserts supports molding parts with:
- Micro-diameter deep inner holes
- Multi-step stepped internal profiles
- Thin-wall hollow structures
- Fine rib and pin boss features
- Flat wide ejection surfaces (flat ejector pins) Standardized and custom pin designs simplify mold layout, boost production speed and improve finished part uniformity.
Key Features & Advantages
- Precision Machining: Ultra-tight tolerance grinding ensures repeatable forming and ejection for micro precision parts.
- High Heat Resistance: SKD61 heat treatment minimizes thermal expansion at sustained mold temperatures.
- Long Service Lifespan: Wear-resistant substrate and optional coatings drastically reduce pin replacement frequency.
- Full Customization: Produce non-standard stepped, multi-stage, flat and ultra-slender pins per client specifications.
Technical Specifications
| Parameter | Specification |
|---|---|
| Base Material | SKD61 Hot Work Tool Steel (Alternatives: D2, SKH51, Tungsten Carbide) |
| Heat Treated Hardness | HRC 48–52 (HRC 60–64 for nitride surface) |
| Dimensional Tolerance | ±0.001mm |
| Straightness & Concentricity | ≤0.002mm |
| Surface Roughness | Ra ≤0.03μm (Ground base; Ra ≤0.01μm polished option) |
| Core Manufacturing Processes | CNC Turning, Cylindrical Grinding, Jig Grinding, Stress Relieving, Hardening & Tempering |
| Surface Treatments | Ion Nitriding, TiN Coating, Mirror Polishing, Plain Ground |
| Customization | 100% Supported per CAD Drawings / Physical Samples |
Applications
- Automotive: Used in injection & die casting molds for automotive plastic housings, sensor components, connector pins and engine plastic accessories, withstanding high-temperature repeated ejection cycles.
- Medical: Suitable for molds of disposable medical plastic fittings, micro fluidic components and surgical device casings, delivering burr-free, high-purity forming surfaces with stable precision.
- Consumer Electronics: Applied in molds for miniature electronic frames, battery housings, connector inserts and thin-wall plastic structural parts requiring ultra-slender micro core pins.
- Plastic Packaging: Ideal for cosmetic containers, threaded bottle caps and small packaging component molds, supporting clean ejection of hollow and fine-feature plastic pieces.
