Analysis: The most fundamental and direct reason is the quantitative change of the printing paper. Firstly, the increase of the belt tension is not appropriate. Secondly, the pressure of the platen roller and platen roller and the blowing amount of the triangular plate are not adjusted properly.
Paper frame tension
The paper frame of M600 is zero-speed paper receiving, the tension between the paper storage rollers is the first tension, and the paper path between the paper storage rollers is lengthened during quick paper connection, which is convenient for receiving paper instantly; there is secondary tension under the paper storage roller The roller, driven by the secondary tension motor, is close to the paper pressing roller (pattern rubber roller) to increase the paper's pressing force; there is a correction roller below, which detects the tape tension, meets the printing requirements, and stabilizes The effect of secondary tension, improper adjustment of the adjustment roller will affect the accuracy of overprinting; there is a deviation correction device behind the paper storage roller, which is used to control the left and right positions of the paper tape into the printing unit, and has little effect on the change of the tape tension.
Printing unit tension
The tension of the paper belt between the printing units is the printing unit tension. The tension between the printing units is not adjustable during the printing process. The hardness, elastic deformation, and plastic deformation of the blanket, whether the blanket belongs to the same brand, its newness and oldness, the thickness of the lining, the printing pressure of each group, the blanket's The degree of tightness, etc. will affect the change of the tension of the printing unit, causing ghosting and overprint failure.
Oven tension
The tension between the last group of printing units and the cooling unit passing through the oven paper belt is the oven tension, which is the longer section of the paper path. The size of the oven tension plays an important role in normal printing, and is also the main reason for the above-mentioned dirty problem. If the tension of the paper tape in the oven is not properly controlled, it will cause paper breaks (excessive tension) and smudging (excessive tension). The rotation speed of the cooling drum should be adjusted according to the basis weight, brittleness, and toughness of the paper, and the pressure between the last cooling drum and the pattern rubber roller should also be adjusted accordingly.
Paper guiding force
The tension of the paper belt from the cooling unit to the triangle platen is the paper guiding force. There are two groups of pressure rollers. The pressure should be adjusted according to the amount or thickness of the paper. The pressure of the front group of pressure rollers is smaller than that of the rear group. The pressure of the pressure roller (on the triangle board) is slightly lighter or the same. The role of the paper pressing wheel is to maintain the tension in this section constant, and its pressure is generally 0.25 ~ 0.3MPa.
Triangle tension
The tension from the paper pressing wheel on the triangular plate to the paper belt on the paper holding roller in the folding machine is the triangular plate tension. The pressure of the upper and lower two groups of pinch rollers in the folding machine is twice the thickness of the printing paper. It is advisable that the paper tape cannot be pulled by hand and the paper tape does not break. Once the adjustment is not good, it will often cause paper breaks. The adjustment of the blowing amount in the set square can solve the dirt caused by this part. The distance between the paper guide rollers under the set square should be adjusted properly. According to the principle of symmetry, the tip of the set square is used as the reference, generally 3 ~ 4 of the printing paper thickness Times, otherwise it will cause the connector to jam the broken paper or the left and right deviation of the signature folding and local rubbing.
In short, a distinguishing feature of rotary printing presses that differs from sheet-fed offset printing presses is the adjustment and control of printing tension. A good grasp of tension can avoid many failures in printing, and can produce high-quality printed products efficiently.
Marble Chopping Board,Cutting Board,Wheat-Straw Cutting Boards,Chopping Board
Yangjiang Yado Kitchen Industry Co., Ltd. , https://www.yadokitchen.com