How to deal with warpage and deformation of plastic mold during injection molding?

Warping and deformation of plastic mold injection products are very troublesome problems. It should be dealt with mainly from the aspect of mold planning, and the adjustment effect of molding conditions is very limited. So, how do we deal with the warping and deformation of plastic mold injection products?

1. When the stress deformation is caused by poor demoulding, it can be dealt with by increasing the number or area of ​​pushrods, setting the demoulding slope, etc.

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 adopting 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, cooling circuits can be placed as close to the deformation as possible.

4. Regarding the deformation caused by the shortening of the molding, it is necessary to revise the design of the mold. Among them, the most important thing is to make the wall thickness of the product uniform. Sometimes, as a last resort, it is necessary to measure the deformation of the product, trim the mold in the opposite direction, and correct it. Resins with a larger shrinkage rate are generally crystalline resins (such as polyoxymethylene, nylon, polypropylene, polyethylene, and PET resins, etc.) than amorphous resins (such as PMMA resin, polyvinyl chloride, polystyrene, ABS resin and AS resin, etc.) deformation is large. In addition, since the glass fiber reinforced resin has fiber orientation, the deformation is also large.