How to solve the warping deformation of plastic mold production?
The warping and deformation of injection products are very difficult problems. It should be mainly solved from the aspect of mold design, and the adjustment effect of forming conditions is very limited. The causes and solutions of warping and deformation can refer to the following:
1) When deformation is caused by residual stress caused by molding conditions, stress can be eliminated by reducing injection pressure, increasing the mold temperature and making the mold temperature uniform, increasing the resin temperature or adopting annealing method.
2) When the stress and deformation are caused by poor demoulding, it can be solved by increasing the number or area of push rods and setting the demoulding slope.
3) If the cooling method is not suitable and the cooling time is not enough, the cooling method can be adjusted and the cooling time can be extended. For example, a cooling loop may be located as close to the deformation as possible.
4) For the deformation caused by the forming shrinkage, the design of the mold must be corrected. Among them, the most important is to pay attention to the product wall thickness is consistent. Sometimes, as a last resort, it is necessary to correct the mold by measuring the deformation of the product and trimming it in the opposite direction. General crystalline resins (such AS polyformaldehyde POM, nylon PA, polypropylene PP, polyethylene PE and polyethylene terephthalate PET, etc.) than non-crystalline resins (such as polymethyl methacrylate PMMA, polyvinyl chloride PVC, polystyrene PS, ABS resin and AS resin, etc.) larger deformation. In addition, the deformation of glass fiber reinforced resin is large because of its fiber alignment.