Multistage rolling mill

A cluster multistage rolling mill comprising:

• a pair of upper and lower work rolls that roll a metal strip;
• an intermediate roll group that supports the work rolls;
• a plurality of partition backing bearing shafts each including a partition backing bearing, a shaft, and a saddle that support the intermediate roll group;
• an upper mill housing that supports an upper side partition backing bearing shafts in a vertical direction, of the partition backing bearing shafts;
• a lower mill housing that supports a lower side partition backing bearing shafts in the vertical direction, of the partition backing bearing shafts;
• a base mill housing disposed on a lower side of the lower mill housing in the vertical direction;
• four columns that link, in an up-down direction, four corners of each of the upper mill housing, the lower mill housing, and the base mill housing;
• a press-down section that is provided on an upper side of the four columns in the vertical direction and that is capable of raising and lowering the upper mill housing;
• and
• a lower mill housing spacer that is provided between the lower mill housing and the base mill housing and that adjusts a position of the lower mill housing in the vertical direction.