B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
B21B—ROLLING OF METAL
B21B39/00—Arrangements for moving, supporting, or positioning work, or controlling its movement, combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
B21B39/20—Revolving, turning-over, or like manipulation of work, e.g. revolving in trio stands
B21B39/28—Revolving, turning-over, or like manipulation of work, e.g. revolving in trio stands by means of guide members shaped to revolve the work during its passage