In order to operate normally, the following points should be paid attention to.
1. The screw should be straight.
2. The design of the screw should be able to withstand the working pressure of the extruder.These pressures may be as high as 70-140mpa (10,000-20000psi) and higher in injection molding.
3. The inner wall of the screw should be more durable than the extruder screw, because the screw is easier to replace than the screw, and the reprocessing is cheaper than the screw.
4. The rear end support should be supported by sliding support, allowing the screw to expand when heated.Rigid support can lead to the bending of the screw, which may lead to serious damage to the screw and screw.
5. In order to improve the group conveying, the feeding section of the screw can be grooved.Good cooling capacity should be ensured in the grooving and solution section to remove the heat generated by high friction and prevent the melting of material in the tank.In addition, the groove should be tilted open, and the depth gradually becomes shallow, minimizing the material's chance to hang material in the construction.
6. If there is no air port, it should be offset, and the opening side wall is tangent to the inner wall of the screw tube to reduce the chance of plastic melt hanging at the front edge of the exhaust outlet.Compared with the traditional design of symmetrical exhaust port, the material is easily blocked at the bottom of the vent.The opening of the exhaust outlet can be designed to be downward sloping to avoid cooling the flow of the extruder.