Design Considerations for Lifters

Design Considerations for Lifters

1. Determine the lifter angle based on the actual stroke (H). The typical angle ranges from 3° to 12°, and the angle should be as small as possible. A standard angle is 5° to 8°. The lifter core-pulling distance should generally be 2–3 mm longer than the product’s core-pulling requirement. For large parts, it should be 5–10 mm longer to ensure smooth demolding.

2. Design the guide block according to the lifter dimensions. Common materials include 40Cr, Bronze, and 738 (surface nitrided).

3. Lifter material should be H13, SKD-61, or FDAC, and must undergo nitriding treatment.

4. Oil grooves must be machined on the lifter surfaces (except top and bottom faces) to ensure smooth sliding.

5. The top surface of the lifter should be 0.05–0.1 mm below the product surface to prevent rubber scraping (dragging) during ejection, which could damage the part surface.

6. For deep parts with lifters on the side, or parts with multiple clips and strict assembly requirements, a stepped locating feature should be added to the lifter to ensure dimensional consistency and stable performance.