Extruder is a kind of common plastic machinery equipment. During the daily operation of the extruder, various failures of the extruder will affect the normal production of plastic machinery. Below we will analyze the failure of the extruder.
Common faults and treatment methods of rod extruder
1.1, abnormal noise
(1) If it occurs in the reducer, it may be caused by bearing damage or poor lubrication, or it may be caused by gear wear, improper installation and adjustment, or poor meshing. It can be solved by replacing bearings, improving lubrication, replacing gears, or adjusting gear meshing conditions.
(2) If the noise is a sharp scraping sound, it should be considered that the position of the barrel is deviated, causing the possibility of scraping the shaft head and the transmission sleeve. It can be solved by adjusting the barrel.
(3) If the barrel makes noise, it may be because the screw is bent to sweep the bore or the set temperature is too low, causing excessive friction of solid particles. It can be processed by straightening the screw or increasing the set temperature.
1.2 Abnormal vibration
If this happens at the reducer, it is caused by the wear of the bearings and gears, which can be solved by replacing the bearings or gears; if it happens at the barrel, it is because of the hard foreign matter mixed in the material, and the cleaning of the material needs to be checked.
The main reasons and solutions for screw extruder wear
2.1 The main reason for screw extruder wear
The normal wear of the screw and barrel of the screw extruder mainly occurs in the feeding area and the metering area. The main cause of wear is caused by the dry friction between the chip particles and the metal surface. When the chip heats up and softens, the wear decreases.
Abnormal wear of the screw and barrel will occur when the screw is locked by ring knots and foreign objects. Ring knot means that the screw is locked by the condensed material. If the screw extruder lacks a good protective device, the powerful driving force may be twisted. If the screw is stuck, it will produce unusually huge resistance, causing serious damage to the surface of the screw and severe scratches on the barrel. The scratches on the barrel are difficult to repair. The barrel is designed to ensure that the service life is longer than that of the screw. For normal barrel wear, it is generally not repaired. The method of repairing the screw thread is often used to restore the radial gap between the inner hole of the barrel and the outer diameter of the screw.
2.2 Solution to screw wear
The local damage of the screw thread is repaired by surfacing welding of special anti-wear and corrosion-resistant alloy. Generally, inert gas shielded welding and plasma argon arc welding are used. Metal spraying technology can also be used for repair. First, grind the outer surface of the worn screw to a depth of about 1.5 mm, and then surfacing the alloy layer to a sufficient size to ensure sufficient
After grinding the outer circle of the screw and the side of the thread to the outer dimension of the screw, the original size is the final machining allowance.
2.3 Annular blockage at the screw entrance
This kind of failure is mainly caused by the cooling water cut-off or insufficient flow. It is necessary to check the cooling system and adjust the cooling water flow and pressure to the specified requirements.
in conclusion
(1) The natural life of the extruder is long, and its service life mainly depends on the wear of the machine and the wear of the gearbox. Choose the extruder and decelerating device of design and material selection and well-manufactured, directly off
In terms of performance, although the equipment investment increases, the service life is prolonged. Considering the overall economic benefits, it is more reasonable.
(2) The normal use of the screw extruder can give full play to the efficiency of the machine and maintain a good working condition. Must be persistently and meticulously maintained to extend the service life of the machine.
(3) The main faults of the screw extruder are abnormal wear, foreign matter jamming, material blockage, wear or damage of transmission parts, poor lubrication or oil leakage, etc. In order to avoid failure, it is necessary to strictly manage the drying, mixing and feeding operations and the setting of the process temperature, and carry out daily maintenance, maintenance and overhaul in strict accordance with the requirements of the "Equipment Point Inspection Standards".
