The significance of printing equipment maintenance

First of all, it can maintain the production to ensure the normal operation of the machine. All the machine fault phenomena affect the production in some different forms, and some of the fault phenomena will even cause a long time to stop production. Therefore, it is very important to quickly remove the machine fault phenomena to ensure the normal operation of the production;Second can reduce the economic loss, improve product quality, reduce production cost, every machine failure phenomenon, is not damaged machine parts, is to make products to be scrapped or any profit: again, machine maintenance for machine maintenance, prolong its service life, keep the equipment precision and good technical state, after the maintenance to the machine, machine parts and return to normal operation state, so that the machine maintenance also in track.

Ii. Equipment maintenance system

Observe the daily maintenance system: strictly observe the operation rules, carefully check the operation of the equipment, and fill the lubrication oil in each drive according to the regulations, so that the equipment is always kept neat, clean, lubricated and safe. If the equipment fails during the shift, timely remove it and make handover records;The site around the equipment is clean and tidy, and the ground is free of oil, garbage and other sundries.

In particular, the maintenance of important parts, such as gears, cams, sprockets, rollers and bearings, which are the most important parts of a screen printing machine, should be strengthened. The maintenance of these parts should be different from that of other parts, because changes in their accuracy will affect the final product.Spring is on the machine used for force balance mechanism of most components, their work is good or bad directly determine the precision level of mutual coordination of the moving parts, spring – must have sensitive elastic, and anelastic and irreversible plastic deformation of spring work is extremely bad, such as found above problem need to be replaced immediately to spring.

The following is the maintenance advice for screen printing machines.

(1) Before starting the work, must according to the maintenance requirements, in each refueling point filling lubricating oil, and need to according to different time, different parts filling different lubricating oil.

For example, before each shift begins, oil must be filled in the following areas.

Guide rail for supporting screen plate: support shaft and connection of scraper and ink cutter, friction surface between wave simple suction tray and roller;Paper feeder and side gauge, etc.The other parts should be lubricated with butter every 1 week.Such as roller sector gear and gear transmission pair;Rolling gear, rack driving pair, CAM working face;Each belt nozzle, etc.Finally, in the annual maintenance of the gearbox, turbine gearbox, the printing rack of oil tanks, etc.

(2) The machine must clean each operating part every month, always keep the drum, the regular table plate and the sensor head clean, avoid ink or dirt blocking the drum suction hole or photoelectric sensor head.

(3) Paper conveyors air valve, drum suction tray should be removed and cleaned once every half a year.

(4) pay attention not to pull, squeeze exposed hose and wire.

Daily and periodic inspection of the printing press

The routine maintenance and regular maintenance of equipment is an effective means to find out the early signs of accidents and eliminate hidden dangers in time, master the natural wear and tear state of spare parts and replace vulnerable parts in time, reduce the accident rate, stop rate and maintain the working phase of printing machine.It is the most important content of three-level maintenance system.

The inspection can be divided into daily inspection, weekly inspection and semi-annual inspection, especially regular inspection of key parts. In case of loose solid parts, serious accidents may occur. Therefore, a small amount of time spent in inspection can eliminate the hidden danger of accidents and ensure safety.

The inspection of screen printing parts includes the following points.

The main frame of the printer is the foundation, the heavier the foundation, the better.

The structure of a printing machine is very important. There are many forces in screen printing. The larger the printing area, the greater the force.If the frame of the press is lighter, it may move during printing, resulting in uneven ink layer, dot size, dot deformation, and overprint.This can be especially serious if some machines are not well maintained.Whether it is new or old machines, carefully check whether there is crack welding, bolt cracks, frame parts dislocation.

(2) Parts configuration should also check the parts close to the gear reducer, motor/pulley, bearing and lifting mechanism.These parts of the screen press are most stressed and are likely to be damaged.

(3) The mechanical operation of screen printing machine should be stable, free, the printing cycle must be no vibration and vibration, dc drive motor is better than ac drive motor, because at low speed, alternating current vibration, will cause printing and ink cover uneven.

The operation of pneumatic motor and hydraulic motor is the same as that of DC drive, and the operation is relatively stable. During the printing cycle, problems can be found by observing the ink coating layer and printing stroke on the screen.If the screen plate is found to be parallel to the scraping plate, it means that there is vibration or vibration in the printing stroke, these ink will appear on the final print.

(4) the requirements of the printing table must be parallel to the scraping plate seat, the error must not exceed 0.005 inches, to measure this parallel degree, with the rotating point of the application brush machine in the rear, this is particularly important.The farther the front side of the printing plate is from the rotation point, the farther the front side of the printing plate is from the rotation point, the greater the error will be.

The higher the tension of the separation distance screen, the smaller the separation distance. Similarly, the smaller the image area, the smaller the separation distance is required.Step printing is the most groove of the separation distance is large, scraper stroke long.In these two cases, the screen spacing of the end of the scraper travel is obviously different from that of the beginning.The use of high tension screen, can minimize this problem, because the high tension screen requires a small distance and separation distance.At the end of the printing stroke, due to the uneven distribution of squeegees pressure will cause dot increase, at this time, coupled with a large separation distance, can only make this phenomenon more serious.

The repeatability of the screen lifting mechanism operation of the printing press is also very important for the control alignment and dot increase.If the printing squeegees drop to different positions each time, the positioning of each printing will be different. To test the alignment error, 15~20 sheets can be printed first, and then reprinted once after drying. The image should be overprinted very accurately.If the paper shrinks, the front of the east printing stroke will overprint well, and the overprint will gradually deteriorate throughout the entire print from front to back.In any case, check the consistency of the overprint. If there is a change in alignment, it is likely due to the inconsistent position of the printing squeegee.You can also carry out two “wet press wet” printing operations, and then observe the dot under the magnifying glass, check whether there is double.If the image has ghosting, it must be the printing squeegee falling in a different position.

Also check the effectiveness of the press locking device.Lower the printing scraper to the printing position and try to move it.If the squeegees are moving, all presses should be equipped with a locking device to prevent the squeegees from moving during the printing process.