GB587466A - Improvements in or relating to rolling mills - Google Patents

Abstract

587,466. Rolling. ABBEY, A. (Standard Machinery Co.). Aug. 17, 1944, No. 15767. [Class 83 (iv)] Reduction rolls are driven with predetermined substantially constant torque at a speed free to vary in accordance with the speed of the stock. As applied to a continuous mill, breaking-down rolls 3 are driven through a coupling 40 at a constant but adjustable speed by a motor 39 such as a D.C. variable speed motor. Edging rolls 4 and reduction rolls 5 are driven by separate hydraulic motors 46, 57, each supplied by its own pump 45, 53 driven by a constant speed A.C. motor 41 which also drives a pump 54 supplying a motor 58 for a take-up reel 33. The rolls 4 are adjustable bodily and simultaneously by right- and lefthanded screws 14 geared at 17 to pinions on a shaft 19 hand operated-at 20. Drive is through face gears 24 meshing with long pinions 25. The pumps 45, 53, 54 may be of positive displacement construction, such as gear or vane type, or of any low pulsation characteristic type for supplying a constant quantity of pressure fluid. The motors 46, 57, 58 may be of any type that develops a torque proportional to the pressure of the fluid. The torque of the motors 46 and 57 is adjusted to exceed slightly that required to drive the rolls in order to maintain a constant tension in the stock, the adjustment being effected by relief valves 61, 62 which may be of the construction described in U.S.A. Specification 1,863,075. When it is desired to maintain the reeling tension constant notwithstanding the accumulation of stock on the reel, a constant power fluid motor is employed at 58. In one such arrangement, a constant displacement pump 68, Fig. 5, draws from a tank 70 and supplies at 71 a pump 69 such that its displacement may be varied by shifting its rotor laterally as described in U.S.A. Specification 2,021,353. In the present arrangement, however, the lateral shift is effected by a piston 73 and opposing spring 74. As the pressure tends to rise in the supply pipe 71, a relief valve 75 supplies the piston 73 causing sufficient decrease in the speed of the motor to maintain the pressure, and therefore the power, substantially constant. Two modifications are described, in one of which control is effected by a lever bearing on the stock on the reel. Hydraulic means may be provided to traverse the reel laterally as the stock is wound. The reel 100, Fig. 8, is mounted on a shaft 101, splined at 104 in the driving worm-wheel 102, and carrying piston 106. Fluid is supplied alternately by pipes 121, 123 from a reversing valve 119 having an arm 130 with a pin and-slot connection to a lever 128 having a fulcrum 129 and pivoted to a lever 131. The levers 128 and 131 are further connected by a spring 135 and the lever 131 is actuated by collars 133 on the shaft 101 giving a snap action to the valve at the ends of the stroke of the piston 106. Fluid is supplied by a motor-driven pump 110 through a metering valve 114, which may be constructed as described in U.S.A. Specification 2,146,537 and is controlled by an arm 142 linked to a lever 138 bearing on the stock at 141 so that as the stock is wound on a larger diameter the speed of traverse of the drum is decreased to maintain close coiling.