Rubber roller printing troubleshooting caused by two cases

Rubber roller printing caused troubleshooting cases of 2020-2 10 - 04 liu, LinJianMing caused by equipment material quality problem in the process of printing printing failures are common, rubber roller as offset press indispensable accessories, has a great influence on the printing quality of the same. The author met twice in the process of printing failures caused by quality of rubber roller, in the process to share with you, this would exclude and summarizes how to correctly use rubber roller. Example a fault performance: in the process of printing, cyan group began to normal color, then slowly becomes shallow. The screening process: (1) down on the plate and ink poles ( Common view pressure method, the use of the roll on plate surface, the ink marks on the surface of the plate width can said pressure size) , found by version water roller pressure, ink mark width is about 9 mm, then adjust the pressure to normal, and then start the machine, and found that the plate mouth diao appear paste version phenomenon, the columns of the dirty phenomenon is more serious, sudden water, water, small repeated phenomenon, layout of water supply is not stable. (2) stop found plate towing pin parts and parts for the rubber jue top water droplets, then check measuring roller, water roller pressure, and switch to normal state, the water supply is normal, fault elimination. On the plate (3) point machine, ink, and found that just tuned by version water roller pressure gets bigger, and water roller pressure regulation by edition of the nut is not loose. We try many times again point machine, found that every time get on version water roller pressure is not the same. (4) will all depend on version of water roll down, found that down to the rubber roller surface smooth, no wear and tear, will be at the ends of the bearing down after careful observation, discover the ends of the roller shaft sleeve eccentric. So we draw the conclusion: rubber roller of eccentric shaft sleeve, cause after installation on version of water roll on the printing plate ink bar, shown at different positions of the circumference of the pressure, the position of the rubber thickness pressure big, if the adjusted according to the position of the pressure, the pressure in the position of the sub thin would be smaller, easy to cause the layout of paste version and dirty; Whereas according to the position of the thin rubber ink bar, pressure adjusting is good after printing, the whole by version water roller pressure is much bigger, the phenomenon of printing ink will occur more and more shallow, and by version water roller pressure will be big and small, layout of water supply is always unstable. When we replaced the new, good quality on version of water roll, fault disappear. The failure reason is that the poor quality rubber roller, national materials and printing workshop without careful inspection, will not pass quality of rubber roller used in printing, to result in failure occurs. Instance two fault performance: in a printing process, we found the magenta ink uneven, appeared on the print position 10 cm width of vertical way. From print diao mouth position to tip position, when the printing color is not stable and jumped clear color, stop up again after printing, began to normal, but when printing from around 300, vertical began to appear. Screening process: because usually, vertical way on the printing quality is caused by the version water roller surface wear, so we first reviewed the rely on version of water roll, found that it does not wear and tear, and is just 10 days ago in saying a roller. Next, we suspect that is caused by the ink emulsification, test education version after liquid concentration, found that the alcohol concentration is larger, the boot after debugging, the fault also appears, no change, Education version fluid are artificial configuration, artificial add alcohol errors unavoidably) 。 Our goal will unload into the measuring roll, doubt its uneven surface hydrophilicity, so that local water amount is too large, lead to vertical layout, but will the color measuring roller and other color group after switching, fault has been eliminated. We think again, if the pressure adjustment is not good, also can appear inky unstable phenomenon, and so will all the ink roller, water roller pressure regulation is normal, but the boot after printing, printing from around 400 when the failure appeared. After normal screening process above, crew and decided to change the red shift of consultation testing-run flat screen of live parts. The living thing to 300 or so, on the printed sheet found three places about 10 cm wide vertical way, and the former one live in the same position, and the living thing's fault phenomenon is more obvious. At this time, everyone thought that appear before caused by version water roller set of eccentric inky fault, so will be screening focus to rely on version of water roll. When we rely on version of water roll will be removed, after the surface is wiped clean, found in its surface has three bright light about 10 cm in width of the color of the rubber and the color of the other location is slightly different, and its position and printing quality fault of vertical position corresponding to the tao. We took water cloth to wipe a few times, found that the hydrophilicity and other positions of the three hydrophilic also slightly different. So we draw the conclusion: the causes of failure is to rely on version of water roll, the hydrophilic rubber coated on the surface of the unevenness of quality is poor. In general the new change of the rubber roller can use more than three months, but the new rubber roller used for 10 days or so, the surface hydrophilicity is bad, it says gelatin roller surface processing poor quality. After communication with the national, they said the rubber roller is used in the new change of rubber roller manufacturer production, to replace the manufacturer thing forget to communication and printing workshop. We have to change another rubber roller manufacturer of rubber roller, printing fault disappear. This article is adapted from 'printing digital printing art'