What is the difference between plastic extruder screw and injection molding machine screw?

Update:05 Mar 2021

 Extruder screw and injection molding machine screw are both plastic processing machinery. They sound a bit similar, but they are actually different. There are many differences between the screw of plastic extruder and the screw of injection molding machine. Now, the professionals of plastic extruder screw will introduce to us to understand more knowledge points of the two machines.

The extruder extrudes the molten plastic through a fixed-shaped extrusion port under the effect of the screw, and cuts it after being water-cooled and shaped under the effect of the tractor. Mainly used for many products with the same cross-section, such as pipes, rods, profiled materials, etc., can also be used for plastic modification and granulation. Its plastic processing is called extrusion molding process.  

The injection molding machine injects molten plastic into the mold, and the product becomes the product after cooling. It has a wide range of uses. Depending on the plastic, the local area used is also different. This process is called injection molding process.
According to our vivid description, the injection molding machine melts the plastic particles and then injects it into the closed cavity. After filling the cavity, the operation is suspended. After cooling, the plastic is shaped into a certain shape, and the operation is performed again after the mold is opened. . Such as plastic cups, plastic basins and other plastic products. The extruder melts the plastic particles and then continuously extrudes them through the mold, such as plastic tubes, plastic plates, etc., and then cuts them off in the subsequent process. The two machines not only process different materials, but also have different screw structures.


Also different to the processed materials, and the viscosity of the materials is different. Injection molding requires the plastic raw materials to flow in the mold, and the runners are generally curved and narrow, so the fluidity of the plastic raw materials must be absolutely good.