Industry news

Processing of plastic products -- the method of eliminating

1、 Causes of fusion marks on products:
Because the first part of the melting material is cooled and solidified in the confluence, there is no strip like fusion mark.
Because the air and the volatile matter of the material are sealed
Mold release agent remained in type 3 cavity.
2、 Associated knowledge:
1. Products with one gate that does not make the materials flow together from two directions generally have no fusion marks, otherwise,
If you want to avoid the weld mark, you can only change the position of the gate to make the weld mark inconspicuous or pleasing to the eye
2. Generally, the pins (holes in the products) on the mould will have fusion marks.
There are many phenomena of fusion marks caused by the air being sealed, so the air must escape completely.
It can also be used in this way: the place where the fusion mark is produced is on the redundant sheet of the product, and then
Slice cut.
If too much mold release agent causes the first part of the melted material to float up and send into the mold cavity, there will certainly be fusion marks.
3、 Solution:
1 instant: increase injection speed, mold temperature, barrel temperature and injection pressure.
2 short term: increase gas escape tank.
3 long term: change gate position
(11) Processing of plastic products -- a method to eliminate the wavy flow pattern of products
1、 The cause of wave flow pattern
1 the resin begins to cool and solidify and enters the mold cavity
2 mold temperature too low
2、 Associated knowledge:
1 at the injection port, the resin cooled in the sliding edge enters the mold cavity in the semi curing state, and solidifies immediately when contacting with the mold,
Then it enters the deep cavity to form the wave current state.
Because of the different thickness of products, it is easy to produce wavy flow lines.
3、 Solution
1 instant: raise the temperature of barrel and mould.
2 short term: improve mold finish.
3 long term: change materials into materials with good fluidity.
4、 According to different materials
1. Materials with good fluidity are not easy to form wavy flow lines
2. The reason for the formation of wavy flow lines in polystyrene is still unclear