Screw Extruder Regular Maintenance Manual
Proper maintenance of screw extruders is essential for extending equipment service life and ensuring consistent production quality. This manual covers all critical maintenance areas from fasteners to drive motors.
1. Fasteners and Transmission System Maintenance
- Regularly check whether fasteners such as screws on the surface of the unit are loose, and tighten them appropriately in time.
- Add or replace the lubricating oil of the transmission box in time (the dirt at the bottom of the oil tank should be cleaned regularly). For new machines, the engine oil should be replaced generally every 3 months, and replaced every 6 months to 1 year after that. The oil filter and suction pipe should be cleaned regularly (once a month).
- The maintenance of the reducer of the extruder is the same as that of general standard reducers. The main task is to check the wear and failure of gears, bearings, etc.
2. Screw and Barrel Maintenance Requirements
- When reinstalling, note that the two screws A and B must be in their original positions and cannot be exchanged! After the newly assembled screw is installed on the machine, it must be turned by hand first, and can only be started at low speed if it rotates normally.
- When the screw or barrel is not used for a long time, anti-rust and anti-fouling measures should be taken, and the screw should be placed hanging.
- When the screw thread block is burned with fire, the flame should move left and right, and clean while burning. Do not burn it too much (turn blue or red), and never put the thread block into water.
- When the extruder needs to be stopped for a long time, apply anti-rust and anti-corrosion grease on the working surfaces of the screw, barrel, machine head, etc. Small screws should be hung in the air or placed in a special wooden box, and padded with wooden blocks to level, so as to avoid screw deformation or bump damage.
3. Temperature Control and Cooling System Maintenance
- Regularly calibrate the temperature control instrument, and check the correctness of its adjustment and the sensitivity of control.
- Distilled water must be used in the cooling water tank in the barrel to prevent scale formation that blocks the cooling water channel in the barrel and causes temperature failure. If blocked, the barrel should be removed for specific maintenance; if there is scale, replace the water with dilute hydrochloric acid for circulation cleaning, then replace with distilled water.
- Check whether the solenoid valve works normally and whether the coil is burned out, and replace it in time if there is any problem.
- Possible causes of failure to rise temperature or continuous temperature rise and failure to fall: whether the thermocouple is loose; whether the heating zone relay works normally; whether the solenoid valve works normally. Replace the deformed heater in time and tighten the screws.
- The inner wall of the cooling water pipe is easy to scale, and the outer part is easy to corrode and rust. Descaling and anti-corrosion cooling measures must be taken during maintenance.
4. Vacuum System and Gearbox Maintenance
- Clean the dirt in the vacuum tank and the materials in the exhaust chamber in time to keep the pipeline unblocked. If the sealing ring of the vacuum pump is worn, it should be replaced in time after regular inspection.
- If the output shaft jumps, it must be that the bearing is damaged and the shaft has broken, and the box must be opened for replacement. If the bearing position of the two output shafts of the gearbox is worn too seriously, the box must be replaced to avoid greater failure losses.
5. Drive Motor Maintenance
Focus on checking the wear and contact of the carbon brush of the DC motor that drives the screw to rotate, and the insulation resistance value of the motor should also be measured frequently to see if it is above the specified value. In addition, check whether the connecting wires and other components are rusted, and take protective measures.
6. Management Requirements
Designate a special person to be responsible for equipment maintenance. Record each maintenance and repair in detail and include it in the factory equipment management file.
