METHOD FOR CONTROLLING FURNACE TEMPERATURE IN HEATING FURNACE

• Main Authors: KITAO SATOSHI, TAIRA MASAMICHI, KOSUGE YASUO, OHASHI YUICHI
• Format: Patent
• Language: English
• Published: 18.05.1992
• Subjects: CHEMISTRY; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS

PURPOSE:To perform the optimum furnace temp. controls for respective billets at real time by determining set furnace temps. in respective zones by defining, as fuzzy variables, the difficulty of burning, the residual heating time, the proportion of decarburizing material, and the contribution rates of respective billets. CONSTITUTION:Prior to the insertion of a billet 2, based on the manufacture instruction, data, and observed value of furnace temp. from a computer 8, a keyboard 11, and thermocouples 5, respectively, computations are exerted in a main control section 7. At this time, the temp.-rise rate necessary to burn from the present billet temp. to the desired temp. at the outlet of zone, the time necessary for the billet to reach the outlet of zone from the present load position, the ratio of decarburizing control material to the total number of loads in every zone, and the contribution rates of respective billets are defined as fuzzy variables. Respective states of the above four variables are regulated according to the modes of changes. Based on the resulting fuzzy control rules, the weights of respective billets in the furnace with respect to the main furnace temp. are determined, and, by the weighted mean by using the above weights as coefficients, the set furnace temps. in respective zones are determined.