Temperature control device of reduction electric furnace for producing sponge titanium

Abstract

The invention provides a temperature control device of a reduction electric furnace for producing sponge titanium. Comprising a programmable controller; the programmable controller receives the target signal, generates an analog signal based on the target signal and the analog temperature signal, and sends the analog signal to the power controller; a power controller; the power controller is in wired connection with the programmable controller, receives the analog signal, generates a power signal based on the analog signal and sends the power signal to the heating resistance tape; heating the resistance tape; the heating resistance tape is arranged in the reduction electric furnace, the heating resistance tape is electrically connected with the power controller, and the heating resistance tape receives a power signal sent by the power controller and adjusts the temperature of the reduction electric furnace according to the power signal. The method has the advantages of convenience and simplicity in control, high flexibility and the like, can greatly improve the technical index of the controlled temperature precision, and has the characteristics of small overshoot, high temperature rise speed, high stability and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature control, and in particular, to a temperature control device for a sponge titanium reduction electric furnace in production. Background Art

[0002] In the process of producing sponge titanium by the magnesium thermal reduction method, the reduction of titanium tetrachloride with magnesium is a long reaction process, lasting for dozens of hours. The temperature control range has a large span, from more than one hundred degrees Celsius to more than nine hundred degrees Celsius, and different temperature values need to be controlled at different reaction stages.

[0003] In the process of the titanium tetrachloride reduction reaction, rapid heating is required at the low-temperature stage, and stable constant temperature is required at the high-temperature stage. However, the total heating power of the reduction electric furnace is as high as 600 kW. When controlled by a traditional contactor, due to the large inertia of resistance heating and the lag of temperature detection, etc., the temperature overshoot is large, the adjustment time is long, and the control accuracy is low. The most ideal error is also ±5°C. Summary of the Invention

[0004] In view of the above-mentioned technical problem of low control accuracy in the existing reduction electric furnace control method, a temperature control device for a sponge titanium reduction electric furnace in production is provided. The present invention mainly controls continuously by combining a programmable controller and a power controller, and can stably control the temperature in the furnace at a set value, meet the process requirements, and ensure the product quality.

[0005] The technical means adopted by the present invention are as follows:

[0006] A temperature control device for a sponge titanium reduction electric furnace in production, comprising:

[0007] An industrial control computer; the industrial control computer is connected to a programmable controller through an Ethernet. The industrial control computer sets different temperature values and constant temperature times in different process time periods and generates a target signal to send to the programmable controller;

[0008] A thermocouple is arranged in the reduction electric furnace. The thermocouple detects the temperature in the furnace and generates a temperature signal to send to a temperature transmitter to be converted into an analog temperature signal. The temperature transmitter sends the analog temperature signal to the programmable controller;

[0009] A programmable controller; the programmable controller receives the target signal and generates an analog signal based on the target signal and the analog temperature signal to send to a power controller;

[0010] A power controller; the power controller is connected to the programmable controller by wire. The power controller receives the analog signal and generates a power signal based on the analog signal to send to a heating resistance belt;

[0011] Heating resistance belt; the heating resistance belt is arranged inside the reduction electric furnace, and the heating resistance belt is electrically connected to a power controller. The heating resistance belt receives the power signal sent by the power controller and adjusts the temperature of the reduction electric furnace according to the power signal.

[0012] Further, the power controller receives an analog signal and adjusts the conduction angle of the triac in the power controller based on the analog signal to send a power signal to the heating resistance belt;

[0013] Further, the heating resistance belts are connected in a triangle on the electric heating furnace, and the heating resistance belts are connected to a three-phase power supply after passing through the power controller and the circuit breaker.

[0014] Further, a temperature detection port for placing a thermocouple is provided on the side of the reduction electric furnace, and the thermocouple is a K-type thermocouple.

[0015] Further, a temperature value and a heating-up time are set on the industrial control computer, and a 4-20 mA signal is output through the analog output AO terminal of the programmable controller to control the output of the power controller, and finally the temperature inside the furnace is controlled.

[0016] Further, the R, S, and T terminals on the power controller are connected to the main power supply through fuses and circuit breakers, the U, V, and W terminals on the power controller are connected to the heating resistance belt, and the AI1 and AI2 on the power controller are connected to the control signal output by the programmable controller.

[0017] Further, when the temperature inside the reduction electric furnace is lower than the set value, the heating resistance belt continuously heats; when the temperature inside the reduction electric furnace is higher than the set value, the heating resistance belt stops heating.

[0018] Further, the formula for the programmable controller to generate an analog signal is as follows:

[0019]

[0020] Where: M(t) is the output of the programmable controller loop, which is a function of time; Kc is the proportional gain of the programmable controller loop; e is the deviation of the programmable controller loop, that is, the difference between the set value SV and the process variable PV; M is the static output value of the programmable controller loop.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] The present invention aims to precisely control the temperature of an electric furnace. Conventional temperature control mainly changes the heating power by the on-off time ratio of a contactor. Due to the large inertia of resistance heating and the lag in temperature detection, etc., the temperature control has a large overshoot, a long adjustment time, and low control accuracy. This device combines a programmable controller and a power controller to continuously heat the electric furnace, adopts a PID control algorithm, realizes intelligent control of the temperature, has the advantages of convenient control, simplicity, and great flexibility, and can greatly improve the technical index of the controlled temperature accuracy, with characteristics such as small overshoot, fast temperature rise, and good stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 It is a schematic diagram of the connection relationship of the device of the present invention.

[0025] In the figure: 1, reduction electric furnace; 2, heating resistance belt; 3, programmable controller; 4, power controller; 5, thermocouple; 6, temperature transmitter; 7, industrial control computer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The following will refer to the drawings and combine the embodiments to detail the present invention.

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. The description of at least one exemplary embodiment is actually only illustrative and in no way restrictive of the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0028] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0029] Unless otherwise specifically stated, the relative arrangements of the components and steps, numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be clear that, for the sake of convenience of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationships. Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the said technologies, methods, and devices should be regarded as part of the authorized specification. In all the examples shown and discussed herein, any specific values should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0030] As Figure 1 shown, the present invention provides a temperature control device for a sponge titanium reduction electric furnace, comprising:

[0031] An industrial control computer 7; the industrial control computer 7 is connected to a programmable controller 3 through an Ethernet network. The industrial control computer 7 sets different temperature values and constant temperature times in different process time periods and generates a target signal to be sent to the programmable controller 3;

[0032] A thermocouple 5 is arranged in the reduction electric furnace 1. The thermocouple 5 detects the temperature in the furnace and generates a temperature signal to be sent to a temperature transmitter 6 to be converted into an analog temperature signal. The temperature transmitter 6 sends the analog temperature signal to the programmable controller 3;

[0033] A programmable controller 3; the programmable controller 3 receives the target signal and generates an analog signal based on the target signal and the analog temperature signal to be sent to a power controller 4;

[0034] The formula for the programmable controller to generate an analog signal is as follows:

[0035]

[0036] Where: M(t) is the output of the programmable logic controller loop and is a function of time; Kc is the proportional gain of the programmable logic controller loop; e is the deviation of the programmable logic controller loop, that is, the difference between the set value SV and the process variable PV; M is the static output value of the programmable logic controller loop.

[0037] Power controller 4; the power controller 4 is wirelessly connected to the programmable logic controller 3, and the power controller 4 receives an analog signal and generates a power signal based on the analog signal and sends it to the heating resistance belt 2;

[0038] Heating resistance belt 2; the heating resistance belt 2 is arranged inside the reduction electric furnace 1, the heating resistance belt 2 is electrically connected to the power controller 4, and the heating resistance belt 2 receives the power signal sent by the power controller 4 and adjusts the temperature of the reduction electric furnace 1 according to the power signal.

[0039] The resistance belt of the reduction electric furnace 1 is continuously powered on, and the power controller 4 is used to adjust the output to make the furnace temperature rise or be kept constant according to the set curve. The power controller 4 can select constant voltage, constant current, constant power or power regulation control through parameters. This device adopts power regulation control, so that the temperature fluctuation of the electric furnace is small, basically controlled within the range of ±1°C of the set value. The industrial control computer 7 is connected to the programmable logic controller 3 through Ethernet. According to the process requirements, different temperature values and constant temperature times are set in different process time periods; a PID adjustment program is compiled inside the programmable logic controller 3 to stably output a 4-20 mA analog signal to control the conduction angle of the triac inside the power controller 4, and the stable output is used to accurately control the temperature inside the furnace; the heating resistance belt 2 is connected in a triangle and is connected to the three-phase power supply through the power controller 4 and the circuit breaker. A high-precision K-type thermocouple is installed to detect the temperature inside the furnace. The mV signal of the thermocouple 5 changing with temperature is converted into a 4-20 mA analog signal by the temperature transmitter 6 and enters the programmable logic controller 3, which is both the display value on the industrial control computer 7 and the input value of the PID control; thus, the temperature inside the furnace is accurately controlled within the range of ±1°C of the set value. A temperature detection port is opened on the side of the reduction electric furnace 1 for installing the K-type thermocouple 5 to detect the temperature inside the furnace.

[0040] The temperature value and the heating-up time are set on the operation screen of the industrial control computer 7, and a 4-20 mA signal is output through the analog output AO terminal of the programmable logic controller 3 to control the output of the power controller 4, and finally control the temperature inside the furnace. The R, S, and T terminals on the power controller 4 are connected to the main power supply through fuses and circuit breakers, the U, V, and W terminals are connected to the heating resistance belt 2, and the AI1 and AI2 are connected to the control signal output by the programmable logic controller 3.

[0041] When the temperature inside the reduction electric furnace 1 is lower than the set value, the heating resistance belt 2 continuously heats; when it is higher than the set value, the heating resistance belt 2 stops heating.

[0042] This patent is a temperature control device for a reduction electric furnace in the production of titanium sponge. According to the existing characteristics of production, the temperature control equipment and technological process of the reduction electric furnace are further optimized. Since the tolerance value of the K-type thermocouple itself is between 1.5 and 4 °C, if higher requirements are needed, a thermocouple detection element with a smaller tolerance value can be used. After the implementation of this device, the temperature control effect is remarkable, meeting the process requirements and ensuring the product quality.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A temperature control device for a sponge titanium reduction electric furnace, characterized in that, Including: An industrial control computer (7); the industrial control computer (7) is connected to a programmable logic controller (3) via Ethernet. The industrial control computer (7) sets different temperature values and constant temperature times during different process time periods and generates a target signal to be sent to the programmable logic controller (3). A thermocouple (5) is provided inside the reduction electric furnace (1). The thermocouple (5) detects the temperature inside the furnace and generates a temperature signal to be sent to a temperature transmitter (6) to be converted into an analog temperature signal. The temperature transmitter (6) sends the analog temperature signal to the programmable logic controller (3). A programmable logic controller (3); the programmable logic controller (3) receives the target signal and generates an analog signal based on the target signal and the analog temperature signal to be sent to a power controller (4). A power controller (4); the power controller (4) is wired to the programmable logic controller (3). The power controller (4) receives the analog signal and generates a power signal based on the analog signal to be sent to a heating resistance belt (2). A heating resistance belt (2); the heating resistance belt (2) is arranged inside the reduction electric furnace (1). The heating resistance belt (2) is electrically connected to the power controller (4). The heating resistance belt (2) receives the power signal sent by the power controller (4) and adjusts the temperature of the reduction electric furnace (1) according to the power signal.

2. The temperature control device for the sponge titanium reduction electric furnace according to claim 1, characterized in that, The power controller (4) receives the analog signal and adjusts the conduction angle of the triac inside the power controller (4) based on the analog signal to send a power signal to the heating resistance belt (2).

3. The temperature control device for the sponge titanium reduction electric furnace according to claim 1, characterized in that, The heating resistance belt (2) is connected in a triangle on the electric heating furnace. The heating resistance belt (2) is connected to a three-phase power supply via the power controller (4) and a circuit breaker.

4. The temperature control device for the titanium sponge reduction electric furnace according to claim 1, wherein A temperature detection port for placing the thermocouple (5) is provided on the side of the reduction electric furnace (1). The thermocouple (5) is a K-type thermocouple.

5. The temperature control device for the titanium sponge reduction electric furnace according to claim 1, characterized in that, Set the temperature value and the heating-up time on the industrial control computer (7). Control the output of the power controller (4) by outputting a 4 - 20 mA signal through the analog output AO terminal of the programmable logic controller (3), and finally control the temperature inside the furnace.

6. The temperature control device for the sponge titanium reduction electric furnace according to claim 1, characterized in that, The R, S, T terminals on the power controller (4) are connected to the main power supply through fuses and circuit breakers. The U, V, W terminals on the power controller (4) are connected to the heating resistance belt (2). The AI1, AI2 on the power controller (4) are connected to the control signal output by the programmable logic controller (3).

7. The temperature control device for the titanium sponge reduction electric furnace according to claim 1, wherein When the temperature inside the reduction electric furnace (1) is lower than the set value, the heating resistance belt (2) continuously heats. When the temperature inside the reduction electric furnace (1) is higher than the set value, the heating resistance belt (2) stops heating.

8. The temperature control device for the sponge titanium reduction electric furnace according to claim 1, wherein The formula for the programmable logic controller to generate an analog signal is as follows: Where: M(t) is the output of the programmable logic controller loop, which is a function of time; Kc is the proportional gain of the programmable logic controller loop; e is the deviation of the programmable logic controller loop, that is, the difference between the set value SV and the process variable PV; M is the static output value of the programmable logic controller loop.

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