Screw pump screw will wear in the process of using, so why screw pump screw will wear, screw pump screw wear what causes it, here we come to understand.

1, each plastic has an ideal plasticizing processing temperature range, should control the barrel processing temperature, make it close to this temperature range. Granular plastic from the hopper into the barrel, the first will arrive at the feeding section in the feeding section will appear dry friction, when the shortage of these plastics are heated, melting, very easy to cause the barrel wall and screw surface wear. Similarly, in the compression section and homogenization section, if the melting state of plastic is uneven, it will cause rapid wear.

2, the speed should be adjusted properly. Some plastics are reinforced with additives, such as glass fibers, minerals, or other fillers. The friction of these materials to metals is much greater than that of molten plastics. In the plastic injection molding, if using high speed, the increase of shear stress on the plastic at the same time, will also strengthen the corresponding to produce more torn fibers, the torn fibers containing sharp ends, to wear a large force to increase. The scraping effect of inorganic minerals on the metal surface is not small at high speed. So the speed should not be adjusted too high.

3, screw in the barrel rotation, the friction between the material and the two, the screw and the barrel of the working surface gradually wear: screw diameter gradually reduced, cylinder bore diameter gradually increased. In this way, the diameter and clearance of the screw and the cylinder are slightly increased with the gradual wear of the two. However, because the resistance of the front head and the splitter plate of the barrel does not change, this increases the leakage flow when the extruded material moves forward, that is, the flow of material increases from the diameter gap to the feed direction. As a result, the production of plastic machinery decreased. This phenomenon increases the residence time of the material in the barrel, resulting in the decomposition of the material. If it is polyethylene, the decomposition of hydrogen chloride gas strengthens the corrosion of the screw and cylinder.

4, the material such as calcium carbonate and glass fiber filler, can speed up the screw and barrel wear.

5, because the material has no uniform plasticizing, or metal contamination material, so that the rotation of the screw torque suddenly increases, the torque exceed the strength limit of the screw, the screw is broken. This is a non conventional accident damage.