Structure and characteristics of plasticized screw for injection molding

The stable plasticization of injection molding materials has great influence on the quality and stability of molding products. In order to develop injection molded products using new molding materials, not only the mold but also the plasticized structure of the injection molding machine should be considered from the beginning. In the injection molding machine will be plastic material molten to the state of injection molding processing, known as plasticization. In today's injection molding machines, more than half of them are plasticizing equipment with on-line screw.

The screw is made of wear-resistant, corrosion-resistant, high-strength metal material, and some screw surface has a special coating. The screw is machined into a spiral groove, which is used to bite material particles (pellets) into the heating cylinder and push it forward. The spiral groove consists of a feeding part, a compression part and a metering part.

1. Feeding part

The feeding part is to introduce the particles that fall from the hopper due to the action of gravity into the heating cylinder. During this period, the particles are preheated and sent to the compression section for melting.

2. Compress the section

The spiral groove of the compression part is machined to a gradually shallower state. The preheated particles are further heated and fused. At the same time of melting, the air mixed with the particle and the resulting gas are vented from the rear of the screw to the hopper side.

3. Measurement part

The metering part is the part where the molten material is further mixed to make it uniformly molten.

Compression ratio is the volume ratio of each pitch of the spiral groove after compression. When determining the volume ratio, it is necessary to consider the melting state of the resin and the spontaneous heat of the resin due to shear. The spiral groove is sometimes also provided with a groove to improve mixing. The mission of Fanstar is to master the core technology of injection molding production, communicate and analyze the technology before mold production with customers from the production needs of finished products, so that the mold delivery time is short, the life is long, the mass production is fast and the finished product quality is excellent! Have the need of injection molding mold welcome to contact us!