Provides high hardness, improved toughness, and general-purpose machinability. The choice depends on production volume, material abrasiveness, and required surface finish. Hardened tool steels like H13 and S7 are recommended for glass-filled nylons and high-volume runs exceeding 500,000 cycles. Stainless steels are used for corrosive resins such as PVC.
Design for turbulent flow (Re > 5000).
Common and easy to machine, but they leave a visible scrap mark on the parting line. injection mold design guide
The gate is the opening that allows molten plastic to enter the mold cavity. Gate type, location, and size dictate filling, packing, part aesthetics, and gate removal. 2. Key Elements of Injection Mold Components An injection mold consists of several critical components:
When thickness changes are unavoidable, use a sloped transition zone. The length of the transition should be at least three times the thickness difference to maintain smooth plastic flow and prevent air traps. 2. Draft Angles and Ejection Stainless steels are used for corrosive resins such as PVC
: Keep walls within the recommended range for your specific material (typically 1.5mm to 4mm for standard thermoplastics). Draft Angles
Copper alloys offer superior thermal conductivity and can be used as inserts in critical cooling areas. The gate is the opening that allows molten
Are draft angles applied to all vertical walls and textured surfaces?
Ensure inside radii are at least 50% of the adjacent wall thickness.
: Move the gate location to change the flow front pattern, increase melt temperature, or increase wall thickness near the knit zone to promote faster material mixing.