The injection molding machine is a thermoplastic molding device that plasticizes solid plastic and then injects it into a closed cavity by means of a screw at a certain pressure and speed, and after curing and setting, obtains the product.
Injection molding machines are generally composed of major components such as injection devices, clamping devices, frames, gearboxes, hydraulic and electrical systems. In the injection molding process, the injection molding machine not only has the rotation, linear and spiral motion of the mechanical equipment, but also the kinetic energy transmission of the hydraulic equipment, and the thermal energy conversion of the electric heating device, which puts more demands on the lubrication work. Of course, for the lubrication of the injection molding machine, we can follow the general rules of lubrication of mechanical equipment, hydraulic equipment and electric heating equipment according to the movement method, but some components (such as injection parts and gearboxes) need to be considered comprehensively, using the method of mixed lubrication. .
(1) Lubrication of manual or semi-automatic plastic injection molding machines
1. Lubrication of gearboxes
Any failure of the gearbox will affect the quality and quantity of the machining. The quenched spur gear and the quenching and tempering shaft in the box should ensure a uniform and reliable lubricating oil film. Generally, the oil cup and the splash lubrication method can meet the lubrication requirements.
2. Lubrication of injection parts
The function of the injection part is to heat the plastic evenly to reach the injection temperature by the electric heating coil, and the injection pressure is formed by the spiral pressing of the pressing rod. Lubrication of the pressure bar generally uses oil cups, oil ropes and other lubrication methods.
3. Lubrication of the clamping part
The clamping part is composed of a pulley, a screw, a nut, a vise and the like. Adjust the position of the collision block on one side of the vise to match the travel switch on the base, and control the feed stroke of the screw to make the vise open and close. Because the screw and nut friction joints are small, the oil film is easily squeezed. Therefore, the lubricating oil should have good oiliness. Generally, L-AN46 oil or HL hydraulic oil is used to lubricate through oil cup and oil rope.
4. Lubrication of the base part
The sliding guides on the base are generally made of cast iron. Because the load and speed of the guide rail are not large, the mineral oil can ensure a certain boundary oil film. Generally, after gently touching the surface of the rail by hand, the oil trace can be seen on the hand, that is, an oil film has been maintained on the rail surface.
(2) Lubrication of automatic hydraulic injection molding machine
The injection molding machine is characterized by high degree of automation, stable performance, and electrical and hydraulic interlocking protection devices with high precision and complicated structure.
1. Lubrication of the injection part
Since this part is completed by injecting the double cylinder to pull the pre-plastic shift gear box, the screw is pushed by the gear box, and the uniformly plasticized plastic is injected into the film cavity to carry out key components of the injection molding. The movement is frequent and there is an electric heating device, and the lubrication system must be strictly enforced. The main lubrication parts of this section:
(1) Add L-AN46 full loss system oil to the injection seat and the rail surface of the rack, once per shift.
(2) Add L-AN46 full loss system oil to the bottom of the gearbox (roller) rails, once per shift.
(3) Add grease to the center of rotation, about 0.3L.
(4) Add about 10L of oil to the L-AN46 full loss system in the gearbox.
2. Lubrication of the moving parts
The mold is hydraulically powered, and the direct pressure type liquid filling device is adopted. The structure is simple, the action is reliable, and the lubrication point is small. Mainly to ensure the formation of lubricating oil film on the four guide columns, L-AN46 mechanical oil can be lubricated through the oil cup and oil rope.
3. Motor lubrication
Most of the automatic hydraulic injection molding machines are driven by multiple motors. When performing daily lubrication, the motor should be lubricated as required.
