Study on Fiber Cutting Performance of Isometric Straight Bar Plate with Different Bar Angle

Abstract

The refining plate is a direct-acting component of refiners in pulping, and the bar profile of it have a major impact on fiber cutting, which affects the paper forming and strength of the formed paper. In this paper, the fiber average length, the fiber length distribution, the original fiber cutting rate and adjacent fiber cutting rate of samples collected in different refining time are used to analyze the fiber cutting mechanism of the isometric straight bar refining plates with different bar angles. The results show that the fiber cutting performance of plates gradually decreases and the limit fiber cutting length of the plate increases with the increase of the bar angle which is opposite to the conclusion predicted by specific edge load (SEL). However, the fiber cutting action of plates is gradually weakened until the average fiber length is reduced to the limit cutting length of plates. Meanwhile, the cutting mechanism of the straight bar plates with different bar angles is different. The larger bar angle of plate, the lower fiber cutting rate and the adjacent cutting rate of which is basically kept constant during refining, while the adjacent cutting rate of smaller bar angle plate on fibers gradually decreases with refining and finally remains constant. The study on the cutting performance of different bar angle plates has positive significance for the selection and design of refining plates for different pulping process.