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Precautions for the production operation of twin-screw extruder

Author: cheerful plastic hi-tech material co.,ltd.Issuing time:2019-07-29 17:20:33Pageviews:604smallmediumbig

The precautions for the production of twin-screw extruders are:
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The precautions for the production of twin-screw extruders are:

(1) When the first screw of the twin-screw extruder is normally produced, it is necessary to first check whether the seal inside the barrel and the hopper is the original closed sample. If there is any change or damage, check whether there is any foreign matter in the hopper or in the barrel.

(2) Check all parts of the equipment according to the order of preparation for trial operation. If turning the coupling during the turning is very laborious or able to rotate but the screw rotates abnormally, the screw should be disassembled to re-check the assembly position of the screw:

1 For the meshing counter-rotating twin-screw, if the assembly position of the two screws is changed, it will not be able to drive production;

2 If the assembly order of the screw components is wrong or the component bonding surface is not clean, this phenomenon will occur.

(3) Note that the screw should be started at a low speed, and the idle time cannot exceed 3 minutes.

(4) Be sure to check the purity of each batch of materials, and do not allow any impurities to be mixed.

(5) Pay attention to the small amount and uniform feeding when driving, and observe the change of the current meter (torque meter). For pellets, metering is used. At the time of initial production, care must be taken to avoid overloading the extruder. After the lip of the mold to be formed is discharged, the screw speed is gradually increased as appropriate.

(6) Always check the working condition of the motor carbon brush, and replace it or adjust it in time.

(7) Special tools should be used for the disassembly of the screw. For the disassembly and installation of the components on the screw, it is necessary to pay attention to the disassembly or assembly sequence. The position of each component should be recorded in sequence, not dislocated, the joint surface should be cleaned, coated with high temperature resistant lubricant, and the screw head should be tightened after assembly. Of course, if the pair of co-rotating twin-screw components are not reassembled, the removed screw only needs to heat the residual material and do not disassemble the components.

(8) The cleaning of the screw is not allowed to be scraped with a steel cutter, and the copper brush and shovel are used for cleaning.

(9) The spline and threaded connection parts of the screw are coated with a layer of molybdenum disulfide lubricant. Do not hit any combination of the components of the screw with a hammer when disassembling the assembled components.

(10) When updating the rear thrust bearing of the screw, remember to adjust the position of the spring and do not install the misalignment.

(11) Pay attention to the installation depth position of the pressure sensor to avoid damage during work.

(12) When it is suspected that the process temperature is displayed on the meter, the mercury thermometer is used to measure the barrel and the temperature to the mold. Adjust the temperature of the calibration instrument according to the measured temperature of the mercury temperature.
2019-07-29 604people