H13 / SKD61 Ejector Sleeves | Custom Mold Parts with Internal Cooling Holes

Product Overview

Senlan Precision manufactures SKD61 die steel ejector sleeves with integrated water line (cooling) holes for injection molding applications. Produced strictly on a Built-to-Print (OEM) basis, these ejector sleeves are engineered to deliver stable ejection, efficient thermal control, and long service life under high-cycle molding conditions.

Key Features & Technical Advantages

• SKD61 hot-work die steel for high thermal fatigue resistance

• Integrated water line hole design to improve heat dissipation

• Optimized hardness and toughness balance after controlled heat treatment

• High concentricity and straightness for smooth ejector movement

• Precision CNC machining and internal grinding for stable tolerances

• Suitable for long-cycle, high-cavity injection mold operation

Application Scenarios / Industry Applications

• Plastic injection molds for bottle caps and closures

• Packaging-related molding systems

• Medical plastic mold tooling requiring stable ejection performance

• Multi-cavity injection molds with enhanced cooling requirements

• Replacement or customized ejector sleeve components

Mold Structure & Design Description

The ejector sleeve works together with ejector pins and core components to release molded parts smoothly. By incorporating a water line hole, localized heat accumulation around the ejection area is reduced, improving cycle stability and minimizing thermal deformation. SKD61 material ensures the sleeve maintains dimensional integrity under repeated thermal and mechanical stress.

Manufacturing Capability & CNC Machining Capacity

Senlan Precision operates advanced precision machining equipment, including:

• MAKINO high-precision CNC machining centers (Japan)

• HARDINGE CNC turning machines (USA)

• CNC turning, milling, deep-hole drilling, internal grinding, and EDM

• Controlled heat treatment and dimensional stabilization

Typical tolerances can be maintained within ±0.003 mm to ±0.01 mm, depending on sleeve length and internal structure.

Custom Development / OEM Cooperation Process

1. Customer drawing and cooling layout review

2. Material and heat treatment specification confirmation

3. Precision CNC machining and water line drilling

4. Heat treatment and stress relief

5. Final grinding and dimensional inspection

6. Packing and export shipment

All parts are manufactured strictly according to customer drawings or technical specifications.

Quality Control & Export Experience

• Incoming material verification and traceability

• In-process dimensional and concentricity inspection

• Hardness and surface quality checks after heat treatment

• Final inspection before shipment

• Stable export experience serving international mold manufacturers

Related Products Recommendation

• Ejector pins and blade ejectors

• Mold core inserts and sleeves

• Cooling core pins and water-cooled mold components

• Multi-cavity mold spare parts

FAQ – Technical & Procurement

Q1: Why is SKD61 suitable for ejector sleeves?
SKD61 provides excellent resistance to heat, wear, and thermal fatigue, making it suitable for repeated injection molding cycles.

Q2: Can the water line hole be customized?
Yes. Diameter, position, and layout are fully customizable based on drawings.

Q3: What tolerances can be achieved?
Concentricity and dimensional tolerances typically range from ±0.003 mm to ±0.01 mm.

Q4: Are these sleeves suitable for multi-cavity molds?
Yes. They are commonly used in high-cavity molds requiring stable cooling and ejection.

Q5: Do you support low-volume or trial orders?
Yes. Prototype, pilot, and mass production orders are supported.

Get a Quote

For technical evaluation and pricing of SKD61 die steel ejector sleeves with water line holes, please contact Senlan Precision with your drawings or specifications. Our engineering team will provide a detailed OEM manufacturing proposal.