Analysis on preventive maintenance of injection mo

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Analysis of preventive maintenance of injection molding machine (II)

inspection of electric wire connectors

wires with loose connectors will cause high temperature or sparks at the connector position and damage, and poor connectors will also affect signal transmission; The connector on the contactor will be easier to loosen due to the vibration of electromagnetic action, so it is necessary to regularly check the position and tightening of the wire connector


generally, the motor is air-cooled, and the accumulation of dust will cause difficulty in heat dissipation, so it is cleaned regularly every year. Usually, the motor overload breaker is installed in the circuit, and the limited current of the protection device is adjustable. Appropriate choices should be made according to the motor power. At the same time, once the overload protector is started, it should be determined to check whether it is under phase, poor contact or high oil temperature before pressing the reset switch back

the heating cylinder and thermocouple

the heating cylinder should be checked regularly to ensure effective heat transfer. The burning of the heating cylinder in normal production is not easy to detect. Therefore, it is necessary to pay attention to the working conditions of the temperature controller magnetic core material tensile testing machine, so as to judge whether the heating cylinder is normal. In addition, the common damage of the heating cylinder is the wire connection. Due to the poor joint, the contact resistance increases, causing local overheating at the connection, resulting in the oxidation and damage of the interface

electromagnetic contactors

the contactors used in the electric heating part, because they mobilize the strength of all aspects of society to act frequently, and their loss speed is also faster. If the main contact overheats and melts and bonds, it may cause the heating temperature to lose control. Therefore, if it is found that the contact overheats, makes a noise or has a large fire when breaking, it is expected to be damaged and should be replaced as soon as possible

computer control part

with the application of microcomputer control technology in the injection molding machine, the normal operation of the microcomputer part and its related auxiliary electronic board puts forward higher requirements for the fluctuation of power supply voltage, the temperature and humidity of the working environment, the seismic resistance of the installation and the interference of external high-frequency signals. Therefore, keep the fan for ventilation and heat dissipation in the control box working normally, and use high-precision power supply voltage stabilizing equipment to supply power, Trying to reduce the influence of external vibration on the control box is the basic requirement of normal work. These problems should be effectively solved and checked regularly

1. Template parallelism

template parallelism can best reflect the condition of the mold locking part. Non parallelism of templates will make products unqualified and increase the wear of equipment and molds. The parallelism of the formwork can be preliminarily reflected by the movement of the tailboard during mold locking and the appearance analysis of the product, but the exact situation needs to be detected by dial indicators and other instruments. The adjustment of formwork parallelism must be carried out by familiar personnel step by step, otherwise improper adjustment will cause greater damage to the machine

2. The die thickness adjustment system should be used regularly to adjust the die thickness from the thickest to the thinnest to ensure smooth operation. For machines produced with the same die for a long time, this inspection must be carried out to avoid failures

3. Central lubrication system

all mechanical moving parts need proper lubrication, and the central lubrication system is one of the necessities of the current injection molding machine. The oil volume of the central lubricating system should be checked frequently to see whether it is full. The lubricating oil used must be clean and free of impurities to ensure that all lubricating positions are supplied with lubricating oil. Replace or repair the oil pipe immediately when it is found to be blocked or leaking. Most mechanical wear occurs due to lack of lubrication, so enough attention should be paid to lubrication

4. Keep all versions shown smooth and effective. The vibration or unsmooth action may be caused by improper speed adjustment, speed change and time mismatch, or mechanical and oil pressure adjustment. Such vibration will accelerate the wear of mechanical parts and vibrate the fastened screws, so it should be reduced and avoided

5. Bearing inspection: when the bearing part is working, there is abnormal sound, or the temperature rises, that is 1 The production and utilization platform of integrated circuit materials indicates that the interior of the bearing has been worn, so it should be checked or replaced in time, and the lubricating grease should be refilled

6. The injection screw, check ring and barrel of the injection system form the heart of the injection molding machine, which determines the quality and efficiency of processing, and they must be kept in good working condition. First, take necessary measures to prevent non plastic debris from mixing into the plastic material flow. Second, pay attention to checking the correct gap between the screw and the barrel, and between the check ring and the barrel. The normal gap should be able to seal the plastic reflux and produce the shear effect required for plasticization. When it is found that the melt action is slow, the melt has spots and black spots, or the product forming is unstable, check the wear of the screw, check ring and barrel. Causes and solutions of some common faults

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