SU1390558A1 - Thermoelectronic method of offline monitoring of time and temperature parameters of thermal treatment of cold-rolled metal - Google Patents

Description

(21) 4152726 / 31-25

(22) 12/04/86

(46) 04.23.88. Bul Number 15

(71) Moscow Institute of Steel and Alloys

(72) V.F. Berdyshev, AMBelenky, A.P. A.Tseitlin

(53), 536.42 (088.8) (56) Belenky A.M. and Blinov O.N. Measurement and control in metallurgical production. Results of science and technology. Metallurgical heat engineering. V. 6, - M .: VINITI, 1968, p. 37-39.

USSR Author's Certificate No. 1237961, cl. G 01 N 25/32, 1984.

(54) METHOD OF THERMOELECTRIC AUTONOMOUS CONTROL OF THE TEMPERATURE-TIME PARAMETERS OF THE HEAT TREATMENT OF COLD-WOODED METAL

(57) The invention relates to heat treatment of a moving metal in units of continuous action and can be used for thermoelectric autonomous control of temperature and time parameters of heat treatment of cold-rolled metal. The purpose of the invention is to increase the accuracy of, speed and reduce the complexity of the control. The thermopower of a natural thermocouple is measured, in which one electrode is made of metal, annealed in a furnace, and the other is made of the same metal before annealing, and the working junction of this thermocouple is heated at a rate of 2-100 ° C / s. Next, the obtained dependence of thermocouple thermocouple on the temperature of its spa is compared with a reference set of previously obtained dependences for various parameters of heat treatment, the closest curve is selected, and its characteristics are identified as the determined parameters of the controlled annealing process in a furnace.

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The invention relates to the heat treatment of a moving metal in aggregates of continuous action and can be used to control the temperature conditions in continuous annealing furnaces in ferrous and non-ferrous metallurgy.

The purpose of the invention is to improve the accuracy, speed and reduce the complexity of the control.

Example. A strip 300 mm long and 2-5 mm wide is cut from the roll mounted on the decoiler in front of the oven. Exactly the same sample is cut off from this place of the coil after the metal undergoes heat treatment in the furnace. Their two bands form a natural thermocouple, the working junction of which heats up at a rate of 40 ° C to a temperature higher than the maximum temperature in the furnace (900 ° C).

In the process of heating, the dependence of the thermopower of the natural thermocouple on the temperature of its spa is measured and, comparing the curve obtained with a set of standard dependences identifying various known parameters of heat treatment, they find the curve that was obtained. The following parameters are assigned to the controlled mode, which correspond to the annealing mode and the curve identical to that obtained: the holding temperature T, the holding time o,., The reheating temperature, the re-holding time Zn, the rate of cooling by gas jets -,.

To simplify the control and increase its accuracy when comparing the analyzed curves, characteristic points are distinguished on the latter: the maximum positive value of the thermopower E J, at the temperature of the thermocouple thermocouple T, the temperature T corresponding to a value of thermoelectric power equal to zero, the steady-state value of thermopower Egp and the value of the corresponding temperature Tg, the values of these parameters of the curve are inserted into the system of regression equations of the form

E, 0.063 0.7. ,, -0, 07.10 T „- & 04 ON C -I- + 0, OMO Td + 0.001 40

Т „200,82 + 3,964 V« ,, -0, 638е „+ 0,216 Тп -0, 141 Т, - 0,158 Т;

T 263,32 - 1,187Г „+ 3,801 V - 0,931Г, -к + 0,246 Тп + 0,124 Tgj

Eftp 0.034 + 0.33. lO Yg + + 0.0840 T "+ 0, -t- + 0.4840- V - 0.01 TgTgp 403.23 - 1.514T" + + 0.621 T - 0.532 T -0, 213 Tp + 1.885 V, ,,.

and calculate the parameters of the annealing.

Claims (1)

Invention Formula The method of thermoelectric autonomous control of temperature-time parameters of heat treatment of cold-rolled metal by annealing the sample and measuring its thermoelectric power, is also due to the fact that, in order to improve accuracy, speed and reduce the labor intensity of control, a natural thermocouple is formed, in which one electrode is made from the metal that has been annealed in the furnace, and the other from the same metal before the annealing, the working junction of this thermocouple is heated at a speed of 2-100 C / s to a temperature exceeding the maximum temperature in the furnace from they measure the dependence of the thermopower of a natural thermocouple on the temperature of its spa and find the desired parameters of the controlled annealing process by comparing the obtained curve with a reference set of similar dependencies for different parameters of heat treatment. VNIIPI Order 1762/44 Circulation 847 Proiz.-polygram. , Uzhgorod, st. Project, 4 Subscription