In this project i have to reduce injection pressure of the molding machine. The existing pressure needed was 88 MPa. Customer wants to reduce more pressure on machine, 80 MPa maximum.
Lower injection pressure means reduce cost (energy) and ensure reliability of the injection molding machine. Lack of injection pressure could lead to short shot phenomena. Because molten could not fill up entire cavity perfectly.
Thickening plastic might be a solution on this issue. Since runner systems were set and made good flow conditions. So increase wall thickness my necessary to achieve goal. Existing part thickness average was 2.5 mm. They allowed us to increase up to 0.5 mm max. Even they allowed us to increase in the whole area.
In other hand, the more thick part the more plastic material needed. Manufacturing cost will eventually increase.
So i decided to increase thickness in certain area only. The fast cooled area were the best area to be thickened. Because you able to compromise cycle time and product quality.
Left: Thickening Area, Right: Lower Injection Pressure
Increase wall-thickness in certain area could decrease injection pressure of molding machine. Above tricks had proven to achieve goal in order to improve machine settings and parameter in shop floor.