Detailed introduction

31

2018

-

07

Zhoushan screw wear solution


 
  ScrewMore used in plastic molding equipment, such as plastic profile extruders, injection molding machines, etc. Screw and barrel are the core components of plastic molding equipment, the part of heating extrusion plasticization, and the core of plastic machinery. The protection of the screw became the primary problem.
Two methods of screw wear:
(1) Each kind of plastic has an ideal processing temperature range, and the processing temperature of the barrel should be controlled to make it close to this temperature range. Granular plastic from the hopper into the barrel, will first reach the feeding section, in the feeding section will inevitably appear dry friction, when the plastic heating is insufficient, uneven melting, it is easy to cause the barrel inner wall and screw surface wear increases. Similarly, in the compression section and the homogenization section, if the melting state of the plastic is uneven, it will also cause faster wear.
(2) the speed should be adjusted properly. Because some plastics are added with reinforcing agents, such as glass fiber, minerals or other fillers. The friction of these substances on the screw is often much greater than that of the molten plastic. In the injection molding of these plastics, if the use of high speed, while increasing the shear force on the plastic, it will also make the reinforcement correspondingly produce more shredded fibers, the shredded fibers contain sharp ends, so that the wear force is greatly increased. Inorganic minerals in the screw surface high-speed sliding, its scraping effect is not small. Therefore, the speed should not be adjusted too high.