How to improve the service life of PVC hose extrusion line

Different conical twin-screw extruder (hereinafter referred to as “cone double”) has its unique feeding area, compression ratio, the screw in the vertical and horizontal material shear and mixing more efficient, better plasticizing ability Therefore, it is especially suitable for producing plastic products with PVC powder filled with high calcium as raw material.

However, the concomitant problem is that the barrel screw of a conical twin-screw extruder suffers from poor service life problems due to the high productivity of the extruder.

Domestic, those small size, high hardness of inorganic calcium carbonate and titanium dioxide to a relatively high, more than 30% or even more than 150% of the proportion of incorporation, mixed with a lot of impurities recycled plastic often used as The main raw materials, barrels and screws in the solid phase friction with these materials increasingly difficult to sustain.

In order to obtain more superior plasticization ability, the material is extruded from a large inlet port of a super-cone extruder to a smaller extrusion end, which further aggravates the dry friction of the solid phase, resulting in a small hole end of the barrel and a small screw Diameter section wear is particularly serious; due to the screw to withstand the back pressure than the average single-screw extruder and parallel twin-screw extruder is larger, and in the cone of double barrel material can be obtained within a short moving distance superior plasticization Ability, specially designed screw helix angle, pitch, meshing gap, but also aggravate the screw to bear the shear wear; and when the distribution box in the thrust bearing due to overwhelming possible wear and tear will also lead to the screw face of the screw Side even in the axial friction with the adjacent screw side, then even worse.

We also have to mention the corrosion of the barrel screw and the high temperature oxidation of the chloride ion releas