Properly improve injection and dwell pressure as well as the injection rate to increase melt’s compression tightness; prolong time of injection and dwell (the freezing of gate should not occur too early) to realize sufficient shrinkage compensation; […]
Properly increase section dimension of gate and runner; the position of gate is set at thick walls of the plastic parts and should be as symmetric as possible; improve mold exhausting condition; […]
The most influential factor for welding intensity is the temperature during the confluence of melt. In actual engineering practice, commonly-used methods for treating welding mark include: […]
The thread mark formed at the front confluence of two or more melt flows in the cavity is called welding mark or welding line. Usually, apart from low mechanical intensity, such defect as depression and aberration may also occur at places where welding mark appears. […]
1 Use plastics with low viscosity and sound fluidity or adjust prescription of plastics and reduce viscosity of melt; 2 Improve barrel temperature, increase injection pressure, raise melt temperature to reduce erection degree, and improve plastication quality; 3 Improve mold temperature and uniformity thereof, raise nozzle temperature and properly set cold-slug well ; 4 Increase [...]
The plastic melt condenses and solidifies before it can smoothly fill in the cavity part far away from the gate or that with thin section, the cavity therefore is insufficiently filled and the shape and structure of the molded products are incomplete, which is intrinsically due to the low fluidity and poor filling capacity of [...]
As a rule, all plates over 50 kg mass must have lifting holes. If possible, lifting holes should be located so that they are not covered by other components and can be used for lifting even after the plate is partly or completely assembled. […]
There are basically two reasons for placing lifting holes on the face of a plate: […]
The location of these holes can only be determined at the completion of the mold design, after the location for all necessary heating and cooling channels and mounting holes and the shape of the mold part are finalized. It is usually best to provide the handling holes as close as possible above the center of [...]
During the design phase, the designer must try to foresee how a mold or mold part will be handled or mishandled. Where the handler, for example, the machinist, assembler, or molding technician, may cause injury to himself or the others. The designer must consider in all case show size, location, and number of tapped holes [...]