JPS55109507A - Controlling system for flow rate of roll coolant oil - Google Patents

Abstract

PURPOSE:To carry out good rolling work depending on the cost-down and improvement of controllability, by applying the pulse width modulation (P.W.M.) method to the control of flow rate of coolant oil on purpose to make shift with single flow rate control valve and to make possible the continuous control. CONSTITUTION:The shape signal Yi of rolled material at each point on the breadth is detected by the shape detector 4, and is inputted to arithmetic processing circuit 5; the circuit 5 compares the signal Yi with the reference signal and operates the distorsion at each point on the breadth, and produces the error signal Ei for each point. Then, this signal Ei is inputted to the pulse generating circuit 6 for generating the pulse signal of PWM, and is converted to the pulse signal Pi which possesses a constant period being sufficiently shorter than the time constant of heat flow in the roll and also possesses the width proportional to the signal Ei. Next, the signal Pi is amplified by the power amplification circuit 7 and is employed as the valve actuating signal for the flow rate control valve 8 for adjusting the flow rate Qi of the roll coolant oil. That is, the oil flow rate Q1...Qi...Qn is produced respectively correspondingly to the shape signal Y1...Yi...Yn at each point on breadth of the material; hereby, the thermal crown of the roll is quickly returned to the suitable value and the rolling work is carried out obtaining good shape product.