Principles of Parting Surfaces in Injection Mold Design
The design of parting surfaces is a critical aspect of injection mold design, impacting the molding process’s ejection, quality, demolding, and efficiency.
Key Principles
1. Maximum Contour Selection
To adhere to the basic demolding principle, according to the three-view principle, the process is initiated by selecting the parting surface at the maximum contour of the plastic part.
2. Facilitating demolding
To streamline the process and minimize mold complexity, ensure parting surfaces allow for smooth demolding and efficient placement of the ejection mechanism.
Since the ejection mechanism of the injection molding machine is located on the movable mold side. To ensure plastic parts stay on the movable mold, choose the right mold parting surface. This will help the ejection mechanism work on the movable side. If the ejection mechanism is installed in the fixed half, it will increase the complexity of the mold.
3. Maintaining Cosmetic Quality
To maintain accuracy and aesthetics, avoid selecting the parting surface between the smooth and visible surfaces of the part.
For high coaxiality, design the parting surface on the same side of the mold cavity.
4. Enhancing Mold Processing Efficiency
To ensure the efficiency of mold processing.
Typically, we choose straight parting surfaces in the mold design. However, to simplify mold making, choose a reasonable parting surface based on actual mold conditions.
5. Ensuring Efficient Venting
Position parting surfaces to aid gas venting at the flow direction’s end, as they are the main exhaust channels.
6. To optimize the side action of core pulling in the mold
Strategically design the parting surface to ensure smooth placement and core-pulling mechanism operation.
Utilizing shallow concaves/short bosses in the pulling direction and deeper concaves/taller bosses in the closing direction.
Also, place the core-pulling system on the movable mold side for better functionality.
7. Ensuring Product Quality and Strength
Consider the influence of parting surfaces on the final product’s quality, strength, and rigidity.
8. Considering the clamping force
Aligning parting surfaces with the clamping direction optimizes mold stability, force distribution, and performance. This ensures the molded parts’ quality and efficiency.