05 on-site processing of an example of an offset press

Our factory has a J2205 bi-color bi-color offset printing press that has used for many years and has caused faults in overprint and inaccurate transfer of printed sheets in one offset printing process. After inspection and analysis, it is confirmed that it is the working surface of the swinging tooth pad (part number: N73-7013802). As well as the bumps associated with the opening and closing of the oscillating teeth (part number: N7370113), the working surface is worn. There are 16 shims for the entire row of oscillating teeth. The degree of wear on each piece is not the same. It cannot be solved through adjustment. Only All replacements can guarantee the normal performance of teething.

At the time, because there were no spare parts for this pad, the production task was tight and the equipment was not allowed to rest. So, in the on-site treatment, we handled this process: without disassembling the dental pad, removing the plate holder with the dental pad, fixing it on the work table of the MD103A grinding and cutting machine of the paper cutter, adjusting the workbench, and grinding The grinding wheel of the knife machine grinds the working surface of the tooth pad on the entire row to the same level. After processing, install the machine, adjust the clenching, and then determine the contour of the convex (part number: N7370133) working face related to the opening and closing of the oscillating teeth, because the face of a bump has worn and two teeth After grinding the work surface of the pad, the working surface of the lug and the working surface of the open roller will be changed and the spacing of the open teeth of the swinging tooth will become smaller, so that the motion of the rubbing paper will be abnormal.

In view of the above situation, based on the influence of grinding on the opening and closing of the teeth after grinding the work surface of the pad, the appropriate bump profile surface is re-determined. We use the method of electric welding to compensate for the adjustment of the teeth. The convex surface (working surface) of the bump is properly compensated, and then the fitter repairs the convex contour of the weld surface so that it can properly cooperate with the working surface of the open tooth roller (and even the performance of the clenching action). It can be normal).

After the above-mentioned treatment, the motion performance of the oscillating tooth returned to normal, and the failure of overprinting was eliminated, which not only solved the lack of spare parts, but also produced a much-needed problem, and extended the use of worn tooth pads and bumps. Better results have accumulated practical experience in dealing with similar faults.