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  Three high mill is a multi pass mill, which is the most commonly used mill. The three rolls of the rolling mill rotate in the same direction from the upper and lower rolls, and the middle roll rotates in the opposite direction. After the rolling piece is rolled out from the pass of the middle and lower rolls, it is transferred to the pass of the middle and upper rolls by the lifting table and the inclined roller table for rolling. Because this rolling mill cuts many grooves on the roll surface, a rolling mill can be used for rolling more than 10 passes, which are mostly used in parallel or semi continuous rolling mills Used as rougher.