Warpage and deformation of plastic injection products are very difficult to handle. It should be dealt with mainly from the aspect of mold planning, while the adjustment of forming conditions is very limited. So, how do we deal with warpage and deformation of plastic mold injection products?

1. When the stress deformation is caused by poor demoulding, it can be treated by increasing the number or area of push rods and setting the demoulding slope.

2. When the residual stress is deformed due to the forming conditions, the stress can be eliminated by decreasing the injection pressure, increasing the mold temperature, increasing the resin temperature or annealing.

3. Because the cooling method is not suitable, when 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, a cooling circuit can be set as close to the deformation as possible.

4. As for the deformation caused by the shortening of forming, it is necessary to revise the planning of the die. Among them, the most important thing is to make the wall thickness of products common. Sometimes, when we have to, we have to measure the deformation of the product and trim the mold in the opposite direction to correct it. For the resin with larger shortening rate, the deformation of crystalline resin (such as polyoxymethylene, nylon, polypropylene, polyethylene and PET resin) is larger than that of non crystalline resin (such as PMMA resin, polyvinyl chloride, polystyrene, ABS resin and as resin). In addition, because the glass fiber reinforced resin has fiber orientation, the deformation is also large.