SU1477753A1 - Apparatus for automatic control of temperature in resistange-heating of metal - Google Patents

Abstract

The invention relates to the field of metallurgy and is intended to automatically control the temperature during the electrocontact heating of the metal. The goal is to stabilize the temperature in the zone of metal deformation by increasing the accuracy of its adjustment. The device contains a voltage sensor 1, a current sensor 2 and a dividing unit 3. A signal is formed in the device, which is proportional to the electrical resistance of the heated metal region. The device also includes a memory unit 4, an adder 5, a task unit 7 and serially connected temperature controllers 6, current 8 and current source 9. In the adder 5, a difference signal is generated between the current signal of the section resistance and the memorized signal in the memory block 4 from the task block 7. This signal controls the source 9 through series-connected temperature and current controllers. The speed of the system provides stabilization of the set temperature with electric contact heating within ± 10 ° С. 1 il.

Description

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The invention relates to metallurgy, in particular, to temperature control during electrical contact heating of a moving metal under plastic deformation, and can be used in mills for strip rolling and wire drawing with electrocontact heating.

The purpose of the invention is to stabilize the temperature in the zone of metal deformation by improving the accuracy of its regulation.

The drawing shows the block diagram of the device

A device for automatic temperature control during electric contact heating of a moving metal section AR directly in front of the deformation zone includes a temperature sensor containing a sensor 1 for voltage taken from section AB and a working current sensor 2, the outputs of which are connected to the first and second inputs of the dividing unit 3. A memory block 4 and an adder 5 are connected to the device, which are connected to a temperature sensor and a temperature controller 6. The inlet temperature controller 6 is connected to the task unit 7, and at the outlet to the current controller 8, the output of which is connected to the current source 9. The second input of current regulator 8 is also connected to current sensor 2. A key 10 is connected to the input of the memory block 4 for controlling the system in a manual or automatic mode of operation.

The device works as follows.

At the initial moment the key 10 is set to the position Manual control. In this mode, memory unit 4 repeats its input signal at the output. The temperature sensor dividing unit 3 divides the signal from the voltage sensor 1 to the signal from the current sensor 2. The converted output signal 2 of the dividing unit 3 is proportional to the electrical resistance of the section AB of the moving metal, which is subjected to electrical contact heating. The electrical resistance of metals has a direct temperature dependence, therefore, the output signal from dividing unit 3 is also proportional to the heating temperature of section AB. The inputs of the adder 5 receives two identical in size, but different in

sign of the signal, so a zero signal is generated at its output. The temperature regulator 6, as well as the current regulator 8 connected in series with it and the current source 9 are controlled by the signal of the reference unit 7. By setting the control signal at block 7 of the task corresponding to the specified heating temperature of the section AB, the control key tO is set to Automatic, the memory unit 4 memorizes the temperature value set by block 7.

Any deviation from the set temperature leads to the appearance at the output of the adder 5 a signal equal to the difference between the incoming signal from the temperature sensor and stored in block 4 of the memory. The output signal of the adder 5 through a series-connected temperature controller 6 and current controller 8 acts on a current source 9, which gives a current corresponding to a given heating temperature of the moving metal in the zone of plastic deformation,

In the device, the temperature sensor generates a signal directly about the change in resistance in the area of electrical contact heating in front of the metal deformation zone, therefore, it has the most speed in comparison with the known temperature sensors. Since the entire control system in the device is associated with a temperature sensor, the device as a whole has an increased response rate which ensures temperature stabilization: in the deformation zone with an accuracy of ± 10 ° C.

Claims (1)

The possibility of ensuring the constancy of temperature at electrocontact heating makes it possible to increase the metal processing rate by an average of 30–40%, as a result, the productivity of the process equipment increases. Invention Formula A device for automatic temperature control during electric contact heating of a metal, mainly for plastic deformation, containing a current source, a temperature sensor connected to a temperature controller, an adder, a current sensor and a current controller, the inputs of which are connected to a current sensor and a temperature controller, and an output with a current source, characterized in that, in order to stabilize the temperature in the metal deformation zone by increasing its control accuracy, it is equipped with a dividing unit, a memory unit and a voltage sensor removed from the heating section metal dividing the output of the voltage sensor is connected to the first input and the current sensor input is connected to the second input of the dividing unit, the output of which is connected to the inputs of the adder directly and through the memory unit, the output of the adder is connected to the input of the temperature regulator, and the key is connected to memory block.