Method and device for eliminating the influence of the ovalization of the cylinders in rolling mills for sheets and strips operating hot and cold

摘要

1,020,775. Rolling. F. MOELLER and K. NEUMANN, [trading as VERWALTUNGSGESELLSCHAFT MOELLER & NEUMANN OFFERE HANDELSGESELLSCHAFT]. Aug. 16, 1963 [Aug. 29, 1962], No. 32501/63. Heading B3M. A method for removing the effect of non- circular rolls in hot or cold sheet and strip rolling mills includes applying a signal which is proportional to the respective algebraic sum of the non-circularity of the rolls, to means for adjusting the roll gap so that changes in the gap due to non-circularity are avoided. As shown, back-up rolls 16 and 17 of a mill having attached coaxially to them discs 35 and 36 which have been previously prepared to indicate in an exaggerated form the error in circularity of the rolls. Roller followers 37b and 38b bear on the discs to actuate differential transformers 37 and 38, electrical signals being passed to a device 46 for forming their algebraic sum. The signal passes to an amplifier 47, a compensator 49, and to a controller 14 which actuates the valve 10 of a pressure transmitter 8 to vary the hydraulic pressure acting on cylinders 4, thus altering the roll gap. The frame is initially prestressed by means of pistons 4, a pressure measuring device 5 sending a signal to the controller 14 corresponding to the rolling pressure. The non-circularity control can thus be additional to conventional roll pass control which depends on the roll pressure. Instead of profiled discs 35 serving as signal sources the roll profiles can be drawn on discs or may be fed on to tapes or film strips, the resulting source being scanned electrically, magnetically or optically.