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  The open type two high up adjusting mill is composed of two horizontal rolls arranged up and down in the same vertical plane. Mainly used in metal rolling process. It can be divided into reversible type and irreversible type. The reversible type includes blooming mill, rail beam mill, medium and heavy plate mill, etc. The irreversible type includes billet continuous rolling mill, laminated sheet rolling mill, sheet or strip cold rolling mill, temper mill, etc.