Heidelberg five color machine operation experience

In the use of Heidelberg Speedmaster 102 five-color offset press, the author summarizes the following operating experience for reference by peers.

1. Gold version piled ink

Stacking ink refers to the phenomenon that excessive ink accumulates on the rubber roller, blanket, or graphic portion of the plate. General rubber pile ink can be solved by adding additives to reduce ink viscosity and wash the blanket. A common cause of ink build-up on rollers and plates is that the ink is heavily emulsified and loses transferability, with gold ink being the most prominent.

When we were printing the Insignia Jinxi brand cigarettes, there was a problem with the water roller of the fifth color ink group, which caused the printing plate to always have a large amount of water, and the large amount of hair blowing was still blowing, making the golden ink emulsified seriously. , there is a stack. Later, by increasing the transitivity of gold ink by adding 10% of varnishes to gold ink, the phenomenon of heap printing is basically eliminated.

2 thin paper folding angle

Due to the use of two equal-diameter cylinders and a double-diameter cylinder in the middle transfer drum of this machine, corners are likely to appear when printing thin paper of 100g/m2 or less, and sometimes there are three or four corners in ten sheets. Even if the anti-folding angle is turned on. Even if the anti-knob blow is turned on, the effect is not very obvious. Even the phenomenon that the winds on both sides are larger and the angle is more serious, it is necessary to shut down some wind eyes. Later, with the elastic pad used to make the die-cut version, the paper trails were clamped and the folding angle disappeared.

The specific method is as follows: first, transfer two printing materials from the transfer cylinder, move it to reach the double-diameter cylinder, tear off the blanks on both sides of the graphic on the print, and paste two or three elastic pads. It can be attached to the corresponding side of a certain color group where there is a fold, or it can be prevented mainly, and it can be fully attached in 5 color groups (the double-diameter rollers must be attached on both sides). If the chamfering occurs after this treatment, it is necessary to attach a resilient pad to the corresponding position on the post-pass roller (the height of the elastic pad is different, and some are cut off half). The reason for cornering sometimes is that the elastic pad is close to the tip, and the paper falls too fast and cannot be clamped. At this time, an elastic pad should be added near the gill mouth.

3. Water roller motor power off

A notable feature of Heidelberg offset presses is the number of safety devices. We have encountered the following situation: Sometimes the machine is running, the water roller motor will be powered off; sometimes it will fly open after operation, the water roller motor will be powered off; sometimes open the air pump and then open the pump, the water roller motor will be powered off . We checked the circuit for a long time and we can't figure out what happened. It was later discovered that the voltage protection device in the control circuit of the water roller motor was sensitive to slight voltage fluctuations, and even if a slight amount of voltage fluctuation was generated during the start-up or opening of the air pump, it could make it move. After we slightly adjust its sensing range, there is very little power outage.