In the production process, the extruder sometimes has poor plasticization, what is the reason?
1. Scorch
1. The phenomenon of scorch
(1) The temperature reflects excessively high, or the temperature control instrument fails, causing the plastic to be extremely high temperature and scorch.
(2) The air outlet of the machine head has large smoke, strong irritating smell, and crackling sound.
(3) Particulate scorch appears on the plastic surface.
(4) There are continuous air holes at the glue joint.
2. The cause of scorch
(1) Super high temperature control causes plastic scorch.
(2) The screw is used for a long time without cleaning, and the scorched material accumulates and is extruded with the plastic.
(3) The heating time is too long, and the plastic deposits will be heated for a long time, which will make the plastic aging and deteriorate and scorch.
(4) The parking time is too long, and the machine head and screw are not cleaned, causing plastic decomposition and scorching.
(5) Multiple mold changes or color changes, causing plastic decomposition and scorching.
(6) The gland of the machine head is not pressed tightly, and the plastic degrades in it.
(7) The temperature control instrument fails, causing scorch after ultra-high temperature.
3. Ways to eliminate scorch
(1) Regularly check whether the heating system is normal.
(2) Clean the screw or head regularly, and thoroughly clean it.
(3) Heating according to the requirements of the process regulations, the heating time should not be too long, if there is a problem with the heating system, you should find relevant personnel to solve it in time.
(4) Change the mold or color in a timely and clean manner to prevent variegation or scorching of the glue.
(5) After adjusting the mold, the mold cover should be pressed tightly to prevent the glue from entering.
(6) Clean the machine head and screw immediately if scorch is found.
2. Poor plasticization
1. Poor plasticization
(1) There is toad skin on the surface of the plastic layer.
(2) The temperature control is low, the meter pointer reflects the low temperature, and the actual measured temperature is also low.
(3) The surface of the plastic is black, and there are tiny cracks or small particles that are not well plasticized.
(4) The plastic glue is not well stitched and there is an obvious trace.
2. Reasons for poor plasticization
(1) Temperature control is too low or inappropriate.
(2) There are resin particles in the plastic that are difficult to plasticize.
(3) Improper operation method, the screw and traction speed are too fast, and the plastic has not completely reached plasticization.
(4) Plastic mixing is not uniform during granulation or there are quality problems in the plastic itself.