A multistage rolling mill includes: four columns 12a, 12b, 12c, and 12d linking, in an up-down direction, four corners of each of an upper mill housing 8, a lower mill housing 9, and a base mill housing 10; a press-down section that is provided on an upper side of the four columns 12a, 12b, 12c, and 12d in a vertical direction and that is capable of raising and lowering the upper mill housing 8; and a lower mill housing spacer that is provided between the lower mill housing 9 and the base mill housing 10 and that adjusts the position of the lower mill housing 9 in the vertical direction. With this configuration, a compact multistage rolling mill with a smaller installation space than a conventional cluster-type rolling mill is provided.

A mandrel with a compensating segment, gripper bar, and external body segment making up a key piece configuration. The configuration adjusting the travel path of metal sheet being wound around the mandrel. The metal sheet thereby being wound without resulting imperfections which occur naturally when wrapping material around a cylinder.

A mandrel with a compensating segment, gripper bar, and external body segment making up a key piece configuration. The configuration adjusting the travel path of metal sheet being wound around the mandrel. The metal sheet thereby being wound without resulting imperfections which occur naturally when wrapping material around a cylinder.

A mandrel with a compensating segment, gripper bar, and external body segment making up a key piece configuration. The configuration adjusting the travel path of metal sheet being wound around the mandrel. The metal sheet thereby being wound without resulting imperfections which occur naturally when wrapping material around a cylinder.

A mandrel with a compensating segment, gripper bar, and external body segment making up a key piece configuration. The configuration adjusting the travel path of metal sheet being wound around the mandrel. The metal sheet thereby being wound without resulting imperfections which occur naturally when wrapping material around a cylinder.