GB728012A - Rolling mill - Google Patents

Abstract

728,012. Rolling. SANDVIKENS JERNVERKS AKTIEBOLAG. Jan. 15, 1953 [Jan. 18, 1962], No. 1222/53. Class 83 (4). A mill for rolling metal strips or sheets of the type having a housing comprising a base connected to a head by side frame members, a pair of rolls journalled in bearing blocks and disposed one above the other with axes horizontal, and means carried by the head for exerting pressure on the bearing blocks of the upper roll is characterized by having adjustable pressure means between the base and the head for stretching the side frame members to some midpoint of their limit of stretching before the start of the rolling operation, the pressure exerted by said means being varied during rolling so as to maintain the total pressure on the side frames, i.e. that exerted by the said adjustable pressure means plus that exerted by the rolls, constant thus keeping the stretch of the side frames, and thus the roll pass, constant. The mill includes a base 1 joined by side frame members 17, in which are mounted bearing blocks 2, 3 for rollers 4, 5, to a head 6 through which screws 7, 8 are threaded to seat against the bearing blocks 3 of the upper roll. The base 1 supports on hydraulic rams 13, 14 legs 11, 12 of a pressure frame of inverted U shape, the flat upper surface of which bears against the flat lower surface of the head 6. The rams 13, 14 may be of the type described in Specification 665,437 to which reference is made, and may be adjustable separately or together to stretch the side frames 17. The stretch of the side frames 17 and thus the spacing of the rolls may be measured by a strain gauge having an indicating element 15. Alternatively or in addition the pressure between the rolls may be measured by a pressure gauge 16. The side frames 17 are prestressed to some mid-point of their limit of stretching and in operation the roll spacing is maintained constant by varying the hydraulic pressure in the rams 13 or 14 either manually, dependent on the readings of the gauges 15 or 16, or automatically by control from one of the gauges, e.g. by an electrical control circuit operating a reversible motor governing the hydraulic pressure.