The plastic extrusion equipment is also constantly improved. During the operation, the solid plastics are transformed into uniform melts by heating, pressurization, shearing and other means, and the melt is transported to the melt of the next process. The production involves the mixing of additives such as masterbatch, the mixing of resin and re pulverization. The melt of the finished product must be uniform in concentration and temperature. To extrude a viscous polymer, the pressure must be large enough.
The extruder completes all the above processes through the barrel with screw and screw channel. The plastic pellets enter the barrel through the hopper at one end of the barrel and are transported to the other end of the barrel through the screw. Due to sufficient pressure, the screw thread depth will decrease as the distance to the hopper becomes longer. The plastic softens and melts due to external heating and the heat generated by friction between the plastic and the screw.
Generally speaking, plastic extruders have different applications in the aspects of discharge outlet, multiple upper feeding ports, special mixing device along the screw, cooling and heating of melt, external heat source, relative size of gap change between the screw and cylinder block, number of screws, etc.
Maintenance common sense:
1. After using the plastic extruder for a period of time, a comprehensive inspection shall be conducted to check the tightness of all screws.
2. In case of power interruption in production, the main drive and heating are stopped. When the power supply is restored, each section of the barrel must be reheated to the specified temperature and kept warm for a period of time before starting the plastic extruder.
3. After the plastic extruder has been used for 500 hours, there will be iron filings or other impurities in the reduction gearbox. Therefore, the gear should be cleaned and the lubricating oil of the reduction gearbox should be replaced.
4. If the steering full degree of the instrument and pointer is found, check whether the contact of the thermocouple contour is good.
