Changshu well da plastic products factory talk about plastic extrusion profiles with black spots

Plastic extrusion molding plastic one of very important processing method in the life of common plastic ventilation pipe, plastic pipe, plastic pipes and so on are all made of plastic extruding. In plastic extrusion process can appear sometimes there are black spots on the extrusion profile, the following works of plastic products factory in changshu to plastic extrusion profiles have black spots and you talk about the cause and the solution.

　　1. Particle surface has not erased the black spots

cleaning machine is not clean; Vacuum port, fiberglass, die head and mouth on the filter plate into residue, retention, high temperature carbonization of materials; High temperature results in a material in the screw, the screw tubes coking; Flame retardant high temperature decomposition, carbonized; Scattered toner bad raw material level more than enough black spots;

　　2. Color/black and yellow lines/oil particles:

steam vacuum mouths objects fall into; Die head, head, stranded on filter plate material carbonization; Decomposition of flame retardant and carbonization; Downtime is too long material decomposition; Article is expected by the regional oil adhesion;

3, the black spots caused by the unstable pressure

a, when there are several kinds of different materials in formula design of screw shall, in accordance with the lowest viscosity of the material and relatively the strongest shear

b, regular cleaning sieve, vent, vacuum mouth and pull out the screw

c, choose coating with low friction coefficient of screw

d, the introduction of the melt pump