Process knowledge of plastic injection machine head
Glue head (Zhi Nihuan) had a rubber rubber meson, materials can be selected full hardening alloy steel powder, Japan Hitachi SKD61, domestic SACM645 domestic 38CrMoALA alloy steel, alloy steel, tungsten steel, 45# steel, H13 and other materials. Glue head ring meson role: glue head group in the plastic injection molding process of plastic melt mixing, molten plastic mixing, glue head defines a role distance.
With the ring apron before and after the combined sealing effect of meson, if the two bad one, the plastic will go back cause, injection molding products, inaccurate measurement, the product will appear yellow serious, dark spots. A rubber ring was introduced: the ring from the style points can be divided into two kinds, one is with a fork, a fork is not over, in pre card in the slot when the plastic screw head with a fork, a rubber ring and rotate with the rotation of the screw.
The utility model has the advantages of: two face wear less, good plasticization. Disadvantages: outer wear quickly, and the barrel bore tolerances or when the debris falling into the barrel in the easy to cause the whole screw does not turn over the other is like. The apron will accelerate the cylinder bore wear. A rubber ring outer wear slower without fork and because it is not how to rotate in the pre plastic, but both ends of the surface wear, if you want to do PVC or PC and other plastic material, with the rubber ring is better, because it can avoid the dead corner so as to avoid the buildup the dark spots. Transparent injection molding products of plastic head ring: three meson screw head small overall smooth surface, in addition to the assembly part outside any one can see the front of the place can not have right angle corner, all parts should be based on the angle of smooth transition. Because the right angle corner, easy crack is not that also easy to make accumulation of materials. The material flow is not clear. For a long time to have three small yellow spots, usually is the most prone to yellowing of the site, do a lot of transparent PC.PMMA products are for three sets of design is not good, resulting in yellow.
