Car Mold Gate Position

There are many forms of mould gate for daily necessities, but no matter what form of mould gate is adopted, its position has a great influence on the forming performance and forming quality of plastic parts. Therefore, the reasonable choice of mold gate opening position is an important design link to improve the quality of plastic parts. When selecting the position of mold gate, the flow state, filling conditions and exhaust conditions of molten plastics in the mold should be analyzed according to the geometric shape characteristics and technical requirements of plastics manufacturing. The mold gate should be set up at the thickest section of the plastic part. When the wall thickness of plastic parts is quite different, if the mold gate is opened in the thin part of the wall, this is the plastic melt into the mold cavity, not only flow resistance, but also easy to cool, affect the flow distance of the melt, difficult to ensure the filling of the whole mold cavity. Plastic parts of the wall thickness is often the most recent melt solidification place, if the gate opened in the wall of thin, so the wall thickness of the place due to plastic melt shrinkage can not be filled and will form a surface depression or shrinkage cavity.

The size and position of mold gate should be chosen to avoid injection and peristalsis. If the small mold gate is directly facing a cavity with a large width and thickness, the melt fracture phenomenon such as injection and creep will occur when the high-speed material flow passes through the gate due to the high shear stress. Sometimes the spray phenomenon will also make plastic parts form a ripple flow mark.

The choice of mold gate position should make the flow of plastics the shortest and the change direction of material flow the least.

The location of the mold gate should be favorable to the gas discharge in the mold cavity.

The material flow should be prevented from squeezing the cavity, core and insert out of shape.