RU94042790A - Method for controlling metal heating in flame furnaces - Google Patents

Abstract

FIELD: metallurgical engineering. SUBSTANCE: invention may be used when conducting various-type heat treatment or when conducting heating before rolling. Invention is aimed at increasing control efficiency, criterion of that being rate of temperature rise to required value with retained quality and economical efficiency of heating. Invention consists in that fuel consumption is controlled after varied, in accordance with preliminarily set program, driving consumption parameter. value of this parameter is varied in the course of process first cyclically - from higher value to lower value each in due cycle, and then by way of adjusting value of last cyclic specification using summation with current value of signal of adjusting action formed by disagreement between current and required temperature values. Time intervals determining duration of cycles are recorded when current value of temperature disagreement reaches specified value in the region of negative unbalance. In this case, controlled value of exaltation of required temperature value is set and, when it becomes a constant constituent of above-mentioned summary signal, a value is used corresponding to minimum allowable value of fuel consumption in accordance with process conditions. EFFECT: provided optimum rate of temperature rise and mild transitory period with ensured restriction of temperature deviation by predetermined limit. 3 dwg

Claims (1)

The invention can be used when carrying out various types of heat treatment or when heated before rolling. Purpose: increasing control efficiency, and the criterion of efficiency is the rate of temperature rise to the desired value while ensuring quality and cost-effectiveness of heating. The essence of the invention: fuel consumption is controlled by a variable in accordance with a pre-set schedule preset flow rate parameter (ZP). The magnitude of the PO in the course of the process is first changed cyclically - from a larger value to a smaller one from cycle to cycle, and then - adjusting the value of the last cyclic task by summing with the current value of the control signal generated by the mismatch between the current temperature and the desired value. The time intervals determining the duration of the cycles are fixed upon reaching the current values of the temperature mismatch of the set values in the region of negative unbalance. In this case, a controlled amount of excess of the required temperature value is established and, when it is achieved, the value corresponding to the minimum possible fuel consumption value is used as the constant component of the said total signal. As a result, an optimum temperature rise rate and a mild transition mode are ensured with a guaranteed limit to the temperature run-out by a set limit.