Based on your previous concerns about avoiding interference from adjacent hot runner cooling channels and the differences in spacing between different mold structures, the core considerations for hot runner mold cooling channel design are as follows:
I. Spacing Compliance Considerations: Channel spacing must strictly conform to the mold structure: for conventional molds, use 3-5 times the channel diameter; the spacing of dedicated hot runner circuits should be ≥30mm to avoid mutual interference of water flow.
The distance between the channel and the heating element in the hot runner should be ≥25mm, and the distance from the cavity surface should be 10-35mm, depending on the structure, to balance cooling efficiency and hot runner temperature stability.
The distance between the channel and ejector pin holes, screw holes, and hot runner sealing points should be ≥8mm to eliminate structural interference and potential leakage.
II. Zoning Layout Considerations: Independent well-type water channels should be set up in the concentrated area of the hot runner nozzles, physically separated from the surrounding conventional cooling circuits to avoid mutual interference of hot and cold water.
The length difference between each branch channel should be ≤10%, and the temperature difference between the cooling water inlet and outlet should be controlled to ≤5℃ to achieve uniform mold temperature distribution.
The water channel direction is consistent with the material flow direction, avoiding hot runner sealing points and reducing uneven local cooling.
III. Special Scenarios Adaptation Considerations: Deep cavity plastic parts utilize spiral cooling water channels to eliminate cooling blind spots in deep cavity areas.
High-precision molds employ conformal cooling water channels, improving cooling uniformity by over 40% compared to traditional straight water channels.
IV. Machining Verification Considerations: Before machining oblique water channels, a vertical positioning platform is pre-milled to prevent drill bit slippage and water channel position displacement.
After machining, the entire water channel diameter is checked using a ball pass to ensure stable water flow and turbulent flow.
During the trial molding stage, the mold temperature distribution is measured, and the water flow rate is fine-tuned to correct design deviations.
