Roll Eccentricity Extraction Method Based on Comprehensive Signal Processing

In modern steel production, strip products account for more than half of the total output. Roll eccentricity is ubiquitous in strip mills, which has a periodic impact on the strip thickness difference. Roll eccentricity compensation is an important part of the automatic gauge control system. Most roll eccentricity compensations extract the roll eccentricity based on the frequency domain analysis of the rolling force. It is difficult to ensure measurement precision of roll eccentricity due to the complexity of interference of the rolling force, therefore the compensation accuracy is difficult to ensure. The roll eccentricity extraction method, based on comprehensive signal processing, was introduced in this paper combined with engineering practice. The roll eccentricity was comprehensively calculated by thickness gauge and other signals that have been delayed; the roll phases were calculated by the roll rotational displacement; and finally, the roll eccentric fluctuation of the upper backup roll and lower backup roll were extracted. The roll eccentricity could be predicted by calculating roll eccentric fluctuations and phases, in order to provide the basis for accurate compensation. According to the comparison with roll eccentricity extracted by the frequency domain analysis of the rolling force, the roll eccentricity obtained by the roll eccentricity extraction method, based on comprehensive signal processing, is more accurate. It provides a reliable basis for roll eccentricity compensation in order to improve the accuracy of the thickness of the strip products.