FIELD: grooved pass of roll of tube rolling mill, mainly round pass for reduction tube rolling mill with three-roll stands, particularly for rolling thin-wall tubes with ratio of wall thickness to diameter more than 1/4. SUBSTANCE: contour of grooved pass of each roll has enlarged-diameter portion in zone of grooved pass bottom for deforming zone of material rolled by means of roll protrusion of respective grooved pass previous in rolling direction. EFFECT: enhanced contour of roll grooved pass preventing or flattening non-desirable sharpened portions on contact surface between rolled product and roll. 3 cl, 2 dwg
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