In the daily work, if the reticulated roll is not used reasonably, it will not only affect the uniform transfer of the ink, thus injure the printing quality of the printed material, but also greatly reduce the service life of the reticulated roll itself. Therefore, the first step in the maintenance of flexographic printing roller is to learn to use it correctly.
Correct use of reticle roll
1. The angle of the reticle roller scraper
The angle between the scraper and the tangent roller contact tangent is usually between 25 degrees and 30 degrees. If the angle is too large, its scraper is almost the top of the reticle roll and the surface of the reticulated roll is not smooth. When it runs at high speed, it will cause the vibration or jump of the elastic scraper piece, which causes the solution to be sprang up, which causes the uneven coating quantity and causes the great difference in the coating quantity. In addition, it is too large to damage the blade.
Two. The sharpness of the scraper of the reticulated roll
The sharpness of the blade depends mainly on the angle of the blade wear, the purity of the solution and the quality of the knife. If it is a new knife, the sharpness of the knife should be effectively scraping the adhesive layer on the anilox roll without producing a knife wire. The sharpness of the knife can effectively clean the solution layer, so as to achieve uniform and uniform coating amount.
Three. The flatness of the scraper of the reticulated roll
If the scraper planeness is not warped, the amount of coating will be uniform, otherwise the difference of the coating amount will be greater. The smoothness of the scraper depends on the method of installing a scraper, and of course it may be related to a foreign object in the slot or blade or lining, so the lining should be cleaned and the new knife is placed behind the lining and loaded into the slot. Screwing back screws should first be tightened from the middle of the blade, then gradually tightened on both sides, and the sides should be tightened round and round. In order to prevent the blade warping, the screw should be completed two or three times when the screw is tightened, one side screw the screw, a piece of cloth is clamped and the blade is clamped and tightened to one side, so that the knife is more smooth, in order to guarantee the standard range of the difference of the coating quantity.
Four, the left and right movement of the scraper of the reticle roll
The movement of the scraper and scraper will play an important role in raising the scraping line, improving the utilization rate of the scraper and reducing the wear of the reticulated roll. In this regard, the wear of the net wall is less, the net is relatively deep, the volume of the fluid filled is more, and it is beneficial to the amount of coating required. The aluminum foil and the binder's optimum coating amount will be heated with the PVC hard sheet after the discussion of the optimum coating amount. The bond strength after heat sealing is usually measured by the thermal sealing strength of the adhesive layer. In a certain range, the thermal sealing strength of aluminum foil and PVC is proportional to the coating amount, but it is not proportional to a certain degree. In most of the test cases, the coating amount of 3 - 6g/cm^2 can meet the requirements of the thermal sealing strength. If the coating amount is increased, the thermal sealing strength will be balanced and the strength change is small after the increase of the coating amount. Therefore, it is not necessary to increase the coating amount of the adhesive, and it will also increase the cost.
Precautions for scraper use:
(1) do not overpress the blade in order to get more hue to increase the wear of anilox and scraper.
(2) do not rotate the dry anilox to the blade.
(3) every time we update the scraper, we need to reset the pressure. The wrong pressure setting will cause scraper fragments and damage roller surface.
(4) stop using the scraper that has exceeded the maximum wear degree, establish the routine process of monitoring the wear and tear of the scraper, control the wear degree of the scraper steadily, and avoid the damage of the reticulated roll.
(5) keep the roller parallel to the scraper at all times, and check and calibrate every 15 days.