Paper Making Machine Fault Maintenance

Cutter device is one of the standard printing plant, used to complete the cut sheet and the printing prepress work after semifinished. Although the operation of the paper cutter is simple, it is prone to some malfunctions during use, which makes the operator unprepared. In this paper, the author analyzes the faults and corresponding maintenance methods in the process of using the “Shenweida” brand paper-cutting machine and the four-open paper-cutting machine in Shanghai, and shares with the readers.

Analysis of fault maintenance of split paper cutter

Fault phenomenon

During the normal use of Shanghai “Shenweida” brand paper cutter, the paper cutter suddenly stops working. After initial setting, the paper cutter resumes normal operation, but when the paper size data is input, the paper cutter Still can't work properly.

2. Failure analysis

We first checked other peripheral lines and components such as the pusher position encoder and found that they were all normal. So, we speculated that there was an error in the device program or the central processor board. If the central processor board has an error, it is divided into memory (U10) 24C44P (8 feet) error and CPU (8085 chip 40 feet) error.

In order to verify the correctness of the above speculation, we first need to check if the device program has an error. The original program to be left is compared with the program stored in the paper cutter and corrected. After all the programs have been corrected, the paper cutter is re-initialized and input the paper size data, and the paper cutter returns to normal. Work, the fault is solved. Therefore, we conclude that the cause of this failure is that the paper cutter's positioning speed has changed during the work of the paper cutter. In this case, as long as the program is corrected, it can be restored to a more ideal state.

The specific correction process is as follows: In the manual program, output 84F, press the Prgmdisplay (program display) button to display each step of the program, the program has a total of 32 steps, the correction program uses the Delete key to eliminate. Then enter the new content and press the Store button.

Analysis of fault maintenance of four-open paper cutter

Fault phenomenon

In the case that the paper cutter has not been fully raised before the cutting machine is finished, the paper feeder pushes the paper forward, causing damage to the paper, and the paper cutter cannot cut the paper normally.

2. Failure analysis

By looking at the equipment drawings of the paper cutter and combining the fault phenomena, we first checked the circuit of the paper cutter, eliminating the “suspect” of the riser position-in-place switch and the rising magnetic induction switch of the paper press, and then focusing on the control. On the small intermediate relay of the paper feeder servo motor.

The small intermediate relay is unplugged for inspection, and the contact is found to be blackened by the arc through the transparent casing, the contact that is blackened by the arc is removed, and the new contact is installed and turned on, and the fault is solved. Therefore, we conclude that the cause of this failure is that the small intermediate relay has a long service life, and the current passing through is large, the contact is ablated, making it poorly contacted, and the small intermediate relay may be disconnected when the paper feeder motor is disconnected. Not broken, causing such a malfunction.

The phenomenon of paper cutter failure is not uncommon in the printing production process. As long as we have the right medicine, it will inevitably reduce the incidence of paper cutter failure, thus improving production efficiency.