How to solve the warpage and deformation of plastic injection molded products?

2021-03-23 12:45:52 admin

How to solve the warpage and deformation of plastic injection molded products?






Warpage and deformation of plastic injection molded products is a very difficult problem. It should be solved mainly from the aspect of mold design, but the effect of adjusting the molding conditions is very limited. So, how do we solve the warpage and deformation of plastic injection molded products?




1. When poor demolding causes stress and deformation, it can be solved by increasing the number or area of push rods and setting demolding slope.


2. When the deformation is caused by the residual stress caused by the molding conditions, the stress can be eliminated by reducing the injection pressure, increasing the mold and making the mold temperature uniform, increasing the resin temperature or using annealing methods.


3. When the cooling method is not suitable, the cooling is uneven or the cooling time is insufficient, the cooling method can be adjusted and the cooling time can be extended. For example, the cooling circuit can be placed as close to the deformed place as possible.


4. For the deformation caused by molding shrinkage, the design of the mold must be revised. Among them, the most important thing is to make the product wall thickness consistent. Sometimes, as a last resort, we have to measure the deformation of the product and trim the mold in the opposite direction for correction. Resins with greater shrinkage are generally crystalline resins (such as polyoxymethylene, nylon, polypropylene, polyethylene and PET resins) than non-crystalline resins (such as PMMA resin, polyvinyl chloride, polystyrene, ABS resin, etc.) The deformation of AS resin, etc.) is large. In addition, since the glass fiber reinforced resin has fiber orientation, the deformation is also large.