1. Proportional valve is unstable – cleaning proportional valve or replacing proportional valve；
2. Damage to the top core bearing – Replace the bearing；
3. Guide rail wear – replace or repair the rail；
4. Paper core deformation – Replace the paper core；
5. The thickness of the paper is different – the production process is solved.
6. The top core device supports the wheel bearing or the copper sleeve wear – replace the support wheel bearing or copper sleeve；
7. The clearance between the support wheel and the guide rail of the core device is too large – Adjust the clearance (the core is clamped at both ends of the top core, and the eccentric shaft of the roller is adjusted to the gap between the roller and the guide rail is 0；