Reducing warpage during injection molding precision parts is a complex and critical process, which involves mold design, injection molding process parameter adjustment, material selection, and subsequent processing. Here are some specific methods and suggestions:
1. Optimize mold design
Cooling system design: Design reasonable cooling water channels in the mold to ensure that all parts of the part can be cooled evenly. This helps to reduce warpage caused by uneven cooling speed. The cooling water channel should be as close to the mold cavity as possible, and consider using circulating water or cooling medium to improve cooling efficiency.
Ejector system optimization: Design a reasonable ejector system to avoid excessive stress and deformation during demolding. The position and number of ejectors should be reasonably arranged according to the shape and size of the part.
Gate design: Optimize the gate position and number to ensure that the plastic melt can fill the mold cavity evenly and smoothly. Reasonable gate design can reduce the generation of weld marks and internal stress, thereby reducing the risk of warpage.
2. Adjust injection molding process parameters
Injection molding pressure and speed: Appropriately reduce the injection molding pressure and speed to reduce the shear heat and orientation effect of the plastic in the mold, thereby reducing the possibility of warping.
Holding time and pressure: Increase the holding time and pressure to ensure that the parts are fully solidified in the mold and reduce the warping caused by uneven shrinkage.
Mold temperature: Control the mold temperature within a certain range to avoid the influence of too high or too low temperature on the cooling speed and shrinkage of the parts. Generally speaking, increasing the mold temperature can reduce the shrinkage difference, but it will also increase the cooling time.
3. Choose the right injection molding material
Material shrinkage: Select injection molding materials with small shrinkage and low internal stress to reduce the deformation of parts during cooling.
Material fluidity: Ensure that the selected material has good fluidity to facilitate filling the mold and reduce the generation of weld marks and internal stress.
4. Strengthen quality control
Raw material quality control: Strictly control the quality of raw materials to ensure batch stability and consistency of raw materials.
Mold maintenance: Regularly inspect and maintain the mold to ensure the precision and surface quality of the mold.
Process parameter monitoring: Real-time monitoring of changes in process parameters during the injection molding process, and timely adjustment to ensure the stability and controllability of the production process.
By comprehensively applying the above methods, the warpage deformation rate of injection molding precision parts can be significantly reduced, and the quality and production efficiency of products can be improved.
