Analysis of common problems of paper machine

Paper break inside the paper machine dryer

Obviously, this cannot be regarded as the cause of vehicle speed, and must be related to process parameters such as steam pressure, paper basis weight, and slurry composition. Even if there may be speed fluctuations, it is not the main thing. Therefore, the craftsman should be assisted to find other reasons.

Paper break in press section of paper machine

The paper break in the press section is a difficult fault to judge. Generally speaking, it is necessary to analyze and judge according to the pressing form and the broken paper position. If it is a compound press, there may be errors in load distribution control related to electricity, and the balance of force between the rollers is lost, so that the paper is subjected to abnormal tension or pressure, resulting in a decrease in strength and an increase in broken ends. The method of judgment is mainly to observe whether the current indication is normal and the size of the swing. If a serious imbalance or abnormal swing is found on the ammeter, you should first perform empty vehicle debugging to find the cause of the imbalance and adjust the parameters to stabilize the system. A simpler way is to stop one or two motors if the load distribution is allowed. That is, let the squeezing part of the multi-point load stop the suspected point and observe whether it is stable. In order to find out the cause of the instability of a single roller first.

The specific inspection parts are:

1) Whether each connection line has poor contact, especially related signal lines, such as feedback lines, communication lines, input and output lines between load distribution points, etc.;

2) Check the PLC program, whether the upper and lower limits of the set parameters are appropriate, whether the calculation program is wrong, whether the program execution is correct, etc.;

3) Check the inverter parameters, whether the torque compensation setting is reasonable, and whether the default parameters are consistent with the motor parameters;

4) Analysis of common failures of paper machine whether the motor is normal, whether there is abnormal sound or abnormal heating, etc. If all of the above are normal, it is preliminarily determined that the electrical is normal, and the reasons for the process and raw materials should be observed.