Abstract: The present invention relates to a compact plant 10 for rolling a seamless tube. The plant comprises a rotary piercer 20 which defines a rolling axis XPR and is designed to pierce a billet 11 pressed against a plug 22 mounted on a rod so as to obtain a pierced blank 12. The rod is connected to a thrust block 26 designed to oppose the axial thrust during piercing. The plant also comprises a longitudinal mill 30 which defines a rolling axis XLL and is designed to roll the pierced blank 12 on a mandrel 32 so as to obtain a semi-finished tube 13. The mandrel is connected to a retaining block 34 designed to impart to the mandrel a predetermined speed during rolling. In the plant 10 according to the invention the rolling axes XPR and XLL coincide. The invention also relates to a method for rolling a seamless tube.

Abstract: The present invention teaches rolling a seamless tube, typically with a large diameter. The system comprises a furnace for heating billets produced by continuous casting. The system comprises a piercing mill for longitudinally piercing the heated billets to obtain a pierced blank. The system comprises an expanding-elongating mill for expanding the pierced blank diameter and for elongating the pierced blank to obtain a semi-finished tube. The system comprises a continuous main rolling mill with adjustable rolls for mandrel-rolling a semi-finished tube. The system comprises a fixed-roll extracting-reducing mill positioned downstream of the main rolling mill. The extracting-reducing mill extracts the semi-finished tube from the mandrel, reducing the diameter to a predetermined value close to that desired for the finished tube. The system comprises an adjustable-roll sizing mill to adjust the radial position of the rolls and define the diameter of the outgoing tube.

Abstract: The present invention relates to a system and method for rolling a seamless tube. The plant comprises a main rolling mill with adjustable rolls for mandrel-rolling a semi-finished tube. The plant also comprises a fixed-roll extracting/reducing mill positioned downstream of the main rolling mill. The extracting/reducing mill is designed to extract the semi-finished tube from the mandrel and reduce its diameter to a predetermined value close to that desired for the finished tube. Finally, the plant comprises a adjustable-roll sizing mill. The sizing mill is positioned downstream of the extracting/reducing mill. This sizing mill is designed to adjust the radial position of the rolls and define the diameter of the outgoing tube.

Abstract: The present invention relates to a system and method for rolling a seamless tube. The plant comprises a main rolling mill with adjustable rolls for mandrel-rolling a semi-finished tube. The plant also comprises a fixed-roll extracting/reducing mill positioned downstream of the main rolling mill. The extracting/reducing mill is designed to extract the semi-finished tube from the mandrel and reduce its diameter to a predetermined value close to that desired for the finished tube. Finally, the plant comprises a adjustable-roll sizing mill. The sizing mill is positioned downstream of the extracting/reducing mill. This sizing mill is designed to adjust the radial position of the rolls and define the diameter of the outgoing tube.