Imprinting roller (lower)

(PRINTING UNIT) In many pressrooms, roll-cup pressure adjustment has always been considered as the work of technicians. However, the printer can check whether the pressure of the bearer is reasonable through the following steps: 1. Make sure that the plate and blanket are padged to the correct height; 2. Raise the blanket and place the pad slightly up to 0.003 inches (about 0.07mm). , and then re-fixed and tightened; 3. In the rubber roller and plate cylinder completely clean and dry conditions, with your fingers dipped in dilute ink gently on the rubber roller on the pillow press on the mark. Note that the ink cannot be of a quick-drying type, and if necessary, the ink can be thinned (by reducing the ink volume). 4. Insulate the paper detection device, start the printer, and start printing. After two or three turns, remove the pressure and shut down. 5. Observe whether there is a fingerprint on the plate cylinder roll. If not, the roller must be adjusted. If there is only a slight imprint in the gap, the roller must be adjusted slightly. If the mark of the clearance is clear and uniform, all around the gear roll and on the side of the operator of the printing press, then there is no need to adjust the roller. Remove the pressure, then pressurize it again and verify it again. 6. Remove the excess paper from the blanket and attach the paper detection device. “Non-bolt contact” adjustment of the printing press roller The non-rolling pillow contact with the printing press does not come into contact with the printing press. The adjustment is relatively intuitive, and its adjustment is basically similar to that of other printing presses. The following are the adjustment procedures for the rollers of a non-rolling pillow contact printer: 1. Place the blanket slightly above the predetermined height, especially those of the old type. 2. Place the printing plate pad to a suitable height and adjust the pressure between the blanket cylinder and the impression cylinder. When there is no paper, press it into 0.004 inch (0.1mm). 3. With reference to the operating instructions to determine the normal height of the underlay, the gap between the bearers should be much; 4. If possible, use a single thickness gauge of the same thickness as a reference. A thin gauge is a thin series of steel sheets with precise thickness and marked accordingly; 5. Keep the rollers clean and dry, isolate the paper detection device and actuate the press to pressurize; 6. When the blanket cylinder is in contact with both the printing plate and the impression cylinder, stop the printing press; 7. Remove the power from the printing press; 8. Insert a thin gauge between the plate cylinder roll and the blanket cylinder; if the cylinder is adjusted correctly, the thin gauge should fit snugly between the rollers, requiring a lot of force to move, and pushing from one side to the other. Can also stay in a new position. During the adjustment, remove the roller pressure little by little and test after the pressure is restored; 9. After the gap is adjusted to a proper state, the excess pad is removed and the paper detecting device is set so that the blanket cylinder and the printing pressure are restored to the normal state. In printing machines produced in some European countries, the plate cylinder is mounted on an eccentric hub, and the distance between the plate cylinder and the blanket cylinder can also be changed by moving the plate cylinder. After adjustment, the ink roller may also need to be readjusted. The blanket cylinder and the impression cylinder are parallel to each other in a non-neck contact printer. The distance adjustment between the eraser/emboss cylinder is also the same as the adjustment between the plate/rubber cylinders, as long as the corresponding parts are adjusted. In any case, the instructions of the manufacturer should be followed to effectively extend the service life of the printing machine. Therefore, the actual condition of the printing press may not be the same as described in this paper. It is the key to clearly understand and carefully implement the manufacturer's regulations. Maintenance The maintenance of printed parts, especially the lubrication work, should be paid special attention. Many machine lubrication tasks are performed automatically by the machine. The issue that needs special attention at this time is to maintain a constant level of oil in the tank. For hand-lubricated machines, lubrication work becomes part of routine maintenance work. Lubrication is relatively simple, but it is therefore often overlooked. Rubber roller fastening wheels, gear worms, jaw shafts, cam followers, etc. all require lubrication. The moving plate clamps also need to be kept clean and require the use of advanced lubricants. For lubrication work, refer to some of the technical instructions provided by the manufacturer. Roller gears are not equipped with lubricant tanks. Advanced lubricants must be used according to the manufacturer's requirements. Before oiling, pay attention to clean the gear teeth from top to bottom, do not leave any ink, paper scraps, cloth or rubber grease. Power transmission rods and crossbars must be cleaned and oiled. Eccentric bushings must be thoroughly lubricated. The oil hole and fixing bolt thread should be kept clean. Each oil hole and grease nipple should be wiped clean with a rag. If the grease nipple is damaged, be careful to replace it in time. Rollers must be kept dry and clean. Do not have ink, glue, and other attachments, because they will gradually damage the pillow. Many presses use chrome plates or stainless plates to prevent the rollers from rusting. Because the rusted part will accumulate high pressure, the drum must be kept clean. If the drum is rusty, wipe it with a delicate cloth and apply a thin layer of engine oil. Be careful not to use trowels, blades, or other bad things to scrape rust. If the printer is equipped with infrared or ultraviolet drying equipment, be careful to use high-temperature lubricant lubrication. Because the dryer can produce very high heat, general lubricants can easily decompose at high temperatures. Note: The clean lubrication must be performed after shutdown; the ink overflowing the printer should be wiped clean to prevent damage to the floor; the anti-toxic filter bag should be placed under the drip tray to absorb the waste oil; replace it every month or according to the situation. If the filter bag is left for a long time, it will not be able to absorb waste oil, and it will also become a source of harmful substances. Preventive Maintenance Preventive maintenance is designed to keep the machine in optimum working condition and prevent equipment from being down. The GATF Technical Service Report 7230 on Preventive Maintenance of Sheet-fed Presses lists a series of routine inspections. For this report, GATF examined the technical manuals of hundreds of printing companies and many printing press manufacturers, and then developed preventive maintenance inspection programs related to five time periods. The low point of the drum low point is much more common than people have imagined, that is, the new machine may also cause the drum to have a low point because of problems with the drum material. A piece of paper, a piece of rag, a screw, or even a folded sheet corner can cause the drum to sag. The damaged area is much larger than imagined. For example, with a small screw, people only see a small pit on the impression cylinder and the blanket cylinder, but you don't know that the large area of ​​invagination it causes is not visible to the naked eye. The following method can be used to find the low position of the blanket cylinder: 1. Normal uplift plate and blanket. Install an old plate on the plate cylinder; 2. Infiltrate the old dry plate completely with ink; 3. Print 20 copies of the solid plate; 4. Reduce the pressure of the cylinder, each time 0.002 inches (0.05mm), continue to print 20 copies. Repeat this process until there are no more impressions on the paper. If the print low fills the entire sheet, clean the blanket and flip it over from head to tail. If the low spots are scattered, this is a problem with blankets. If the low point is fixed at the same point, it indicates that one of the rollers has a low point or the roller is not properly aligned. At this time, the manufacturer must be resolved.