The problem at hand is related to uneven corrugating roll nip pressure loading during the manufacturing process of combined board. This type of issue can result in non-uniform wear and variable quality convertibility across the sheet. Upon investigation, it has been observed that there is heavy pressure on the operator's side while the drive side has light pressure, indicating that the roll pressure is not uniform.

Several factors may contribute to this problem, including hydraulic, pneumatic, or manual pressure adjustments being out of control. In such a case, adjusting and equalizing roll pressure can help alleviate the issue. Another possible factor could be an out-of-calibration loading gauge, which can be resolved by checking and correcting the gauges. Lastly, if the pressure cylinders are malfunctioning, repairing the malfunction in pressure cylinders can resolve the issue.

It is worth noting that this issue can cause excessive wear in the center and variable convertibility across the sheet, leading to a reduction in the quality of the final product. Therefore, it is crucial to address the problem promptly and accurately.