Injection molding machine production is generally done 24 hours a day. For machines that have been in operation for a long time, maintenance work must be done well, and efforts must be made to identify and solve problems before the machine malfunctions. Otherwise, once the machine malfunctions, it must be shut down and repaired, affecting production.
Maintenance of electrical systems:
(1) When checking the high-voltage components inside the machine, the main power should not be turned on unless necessary.
(2) When replacing the mold, do not allow cooling water to flow into the electric control box.
(3) Check if the temperature inside the electronic control box is too high, which may affect the normal operation and service life of the electronic board.
(4) When replacing a relay, the specified voltage relay should be used.
The maintenance of the hydraulic system of the injection molding machine should maintain the hydraulic oil temperature between 30-55 degrees Celsius. If the oil temperature exceeds 60 degrees Celsius, the following problems may occur:
(1) Hydraulic oil deteriorates due to oxidation.
(2) The decrease in hydraulic oil viscosity leads to damage to the oil pump, oil leakage, pressure drop, and a decrease in overall efficiency.
(3) Accelerate the rate of oil seal aging.
(4) Prevent cooling water from leaking into the system oil tank, and pay special attention to checking whether there is any water leakage inside the oil cooler. Clean the inside of the cooler every 6 months or so.
(5) The hydraulic oil of the injection molding machine must be changed every 3000 to 4000 hours of operation. When changing the oil, it is not allowed to mix new and old oil, and the filter inside the oil tank should be twisted off for cleaning.
(6) The directional valve fails due to blockage of the valve core by foreign objects. The valve core should be removed and cleaned with diesel or kerosene (or immersed in clean hydraulic oil for cleaning), and then compressed air should be used to remove foreign objects.
Maintenance of the locking part:
(1) The working life of the machine hinge in the locking part is very long, but each moving part should be properly lubricated, otherwise the machine hinge will wear and reduce its lifespan.
(2) Keep the four pull rods clean.
(3) Keep the sliding feet and rails of the moving template clean and lubricated.
(4) Avoid using molds that are close to or exceed the working pressure.
(5) When adjusting the mold, the fast locking speed cannot be used.
(6) Control the stroke position of the mold locking action to the most appropriate position to reduce the impact on the machine during mold locking.
Maintenance of the glue injection section:
(1) Maintain lubrication and cleanliness of the shooting table guide rod.
(2) Keep the surface of the shooting table clean and dry.
(3) When using recycled materials, a hopper magnetic frame must be added to the hopper to prevent metal fragments from entering the glue cylinder.
(4) The temperature of the material barrel reaches the set temperature for about 3 minutes before production (ensuring that the raw materials inside the barrel are completely softened) to prevent damage to the screw and transmission system.
(5) When the material barrel has not reached the preset temperature, the glue melting motor cannot be started, and the reverse cable (loosening) action cannot be used to avoid damaging the rotating system components.
(6) Use the correct method provided by the plastic supplier for replacing plastic and cleaning the melt cartridge.
(7) Regularly inspect all parts of the injection table, tighten any loose parts, and ensure that the two injection cylinders are installed evenly to prevent damage to the oil seal of the injection cylinder, oil leakage, and damage to the cylinder, piston rod, etc.
(8) When the temperature of the glue is normal but there are continuous black spots or discoloration of the glue, the thrust ring and thrust ring of the glue injection screw should be checked for damage.