Heat tracing control device capable of automatically starting and stopping depending on natural temperature change

Abstract

The utility model relates to the technical field of thermotechnical fluid medium sampling, and discloses a heat tracing control device capable of automatically starting and stopping depending on natural temperature change, which comprises a heat tracing component and a temperature control unit, the heat tracing component comprises a heating part and a heating relay, and a normally open end of the heating relay is communicated with a power supply; the first temperature control assembly and the second temperature control assembly are connected with the heating relay in series, and through setting of an alarm value, the heating part heats the flow guide pipe only when the temperatures detected by the first temperature control assembly and the second temperature control assembly are lower than the alarm value, so that the situation that ice is accumulated in the flow guide pipe due to too low external environment temperature is avoided; the normal work of a thermotechnical fluid medium sampling measuring point is influenced; meanwhile, when the external environment temperature rises, the detection temperature of the second temperature control assembly is higher than an alarm value, so that the control loops connected in series are disconnected, heating is stopped, and the utilization efficiency of energy is improved; in addition, manual intervention is not needed in the whole process of the scheme, so that the problem of commissioning omission caused by manual commissioning is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of thermal fluid medium sampling, in particular to a heat tracing control device which automatically starts and stops depending on natural temperature changes. Background Art

[0002] During the operation of a power plant, thermal fluid medium sampling points are mainly used to collect gas or liquid medium samples, and introduce them into measuring instruments through drainage pipes for processing to achieve real-time monitoring of medium parameters. However, when the temperature drops to near freezing point, the moisture in the liquid medium or the water vapor contained in the gas medium will condense to form ice in the drainage pipe, causing the pipe to be blocked. This situation not only affects the accuracy of medium measurement, but may also cause operating personnel to misjudge the operating conditions, and even cause serious consequences such as unit tripping in extreme cases. In order to solve the above problems, it is currently common to install a heating component to maintain the temperature of the sampling medium. By setting a heating part on the drainage pipe, the medium sample collected in the drainage pipe is heated, and a layer of insulation layer is wrapped around the drainage pipe and the heating part to maintain the temperature of the medium in the drainage pipe to prevent the medium sample from freezing in a low temperature environment and blocking the drainage pipe. However, the existing heating components have the following deficiencies in actual application:

[0003] 1. High labor costs: Thermal measurement points within the power plant are widely distributed, some of which are located outdoors. Every year, before the temperature plummets, workers must manually activate the heating components. The large number and scattered distribution of measurement points not only increases the workload but also leads to higher labor costs.

[0004] 2. Risk of missed commissioning: Since the heating components need to be started manually one by one, and the number of measuring points is large, negligence or omissions are prone to occur, resulting in the failure to start the heating device in time at some measuring points, and the medium may freeze when the temperature drops sharply.

[0005] 3. Heating Exit Lag: When the temperature gradually rises, if the heating component is not turned off in time, it will cause unnecessary energy consumption. In addition, if the heating component is forgotten to be turned off and continues to heat in hot summer weather, it may cause the measured medium temperature to be too high, thus affecting the accuracy of the measurement results. Utility Model Content

[0006] The existence of the above problems not only increases the operating costs of power plants, but also may pose a threat to the safe operation of power plants.

[0007] The utility model aims to provide a heat tracing control device that automatically starts and stops depending on natural temperature changes, so as to reduce manual intervention, improve energy utilization efficiency, and ensure the normal operation of thermal fluid medium sampling and measuring points.

[0008] To achieve the above-mentioned objectives, the present invention adopts the following technical solutions: a heating control device that automatically starts and stops depending on natural temperature changes, comprising a heating component and a temperature control unit, the heating component comprising an insulation layer and a heating element, the insulation layer being wrapped around the outside of a flow guide tube, the heating element comprising a heating portion and a heating relay, the heating portion being arranged between the flow guide tube and the insulation layer and electrically connected to the heating relay, the heating relay comprising a normally open end and a relay excitation end, the normally open end being connected to a power supply; the temperature control unit comprising a first temperature control component for measuring and controlling the temperature of the interlayer between the flow guide tube and the insulation layer, and a second temperature control component for measuring and controlling the real-time ambient temperature; the first temperature control component is a temperature controller having a solid-state relay, and the second temperature control component is a temperature controller having a low temperature threshold alarm output port; the low temperature threshold alarm output port, the solid-state relay, and the relay excitation end are sequentially connected in series to form a control circuit, the first temperature control component and the second temperature control component are both provided with an alarm value, and when the measured temperature is lower than the alarm value, the control circuit is connected.

[0009] The beneficial effects of this solution are as follows: the device comprises a heating assembly and a temperature control unit, the heating assembly including a heating part and a heating relay, the normally open end of the heating relay being connected to a power source, the first temperature control assembly and the second temperature control assembly being connected in series with the heating relay, and by setting a warning value, only when the detected temperatures of the first temperature control assembly and the second temperature control assembly are both lower than the warning value, the excitation end of the heating relay is connected to generate an excitation voltage, which serves as the power supply for the heating part, so that the heating part heats the guide tube, thereby preventing the external ambient temperature from being too low, causing water accumulation in the guide tube and even blockage, which affects the normal operation of the thermal fluid medium sampling point; at the same time, when the external ambient temperature rises, the detected temperature of the second temperature control assembly exceeds the warning value, causing the series control loop to be disconnected, the excitation end of the heating relay to be disconnected, and thus the power supply to the heating part is disconnected, cutting off the energy supply to the heating part. Without power supply, the heating part naturally cuts off heating, thereby improving energy utilization efficiency; in addition, this solution does not require manual intervention throughout the process, thereby avoiding the manual commissioning work required before a sudden drop in temperature and the problem of commissioning omissions that may exist in manual commissioning.

[0010] Furthermore, the first temperature control component is connected to a temperature measuring element, which includes a detection part, and the detection part is fixedly arranged in the interlayer between the guide tube and the insulation layer.

[0011] Beneficial effect: Fixing the detection part of the temperature measuring element between the flow guide tube and the thermal insulation layer can ensure the accuracy of the temperature measured by the first temperature control component and reduce measurement errors.

[0012] Furthermore, the first temperature control component is provided with a temperature input port, which is connected to the temperature measuring element.

[0013] Beneficial effect: The temperature measuring element is connected to the first temperature control component through the temperature input port. When the temperature measuring element needs to be corrected or replaced, it only needs to be unplugged, thereby reducing the difficulty of maintenance.

[0014] Furthermore, the power supply is 220V AC.

[0015] Beneficial effects: Utilizing 220V AC power supply, no additional transformer is required, thus eliminating the cost of transformer and its related installation and maintenance, improving the economy of the system, and reducing the cost and circuit complexity.

[0016] Furthermore, the invention also includes a control box, which is provided with an inner door. Two square holes for fixing and installing the thermostat are symmetrically opened side by side on the inner door.

[0017] Furthermore, the inner wall of the control box is provided with a slide groove for installing the heating relay.

[0018] Beneficial effect: The heating relay and the temperature controller are installed in the control box, making the device relatively independent and easy to carry and arrange.

[0019] Furthermore, the warning value of the first temperature control component is 30°C, and the warning value of the second temperature control component is 1°C.

[0020] In combination with the above technical features, the working principle of this application is as follows:

[0021] First temperature control component: Set the first temperature control component's warning value to 30°C. The first temperature control component is connected to a temperature measuring element via its temperature input port. The temperature measuring element's detection unit is fixedly located in the interlayer between the flow tube and the insulation layer, ensuring accurate temperature measurements. When the interlayer temperature falls below 30°C, the first temperature control component outputs a 24V DC voltage as the excitation voltage for the relay. At this point, the normally open terminal of the heating relay closes, allowing 220V AC power to flow through the heating relay to power the heating element, heating the flow tube. This forms the main heating control circuit.

[0022] Second temperature control component: Set the second temperature control component's alarm threshold to 1°C. The second temperature control component monitors the ambient temperature in real time. When the ambient temperature falls below 1°C, the second temperature control component's low temperature threshold alarm output port turns on. When the ambient temperature rises above 1°C, the low temperature threshold alarm output port turns off. This low temperature threshold alarm output port is connected to the main heating control circuit, acting as a switch that automatically starts and stops the heating according to changes in the ambient temperature.

[0023] The overall control logic is as follows:

[0024] 1. When the outside temperature is lower than 1°C, the low temperature threshold alarm output port of the second temperature control component is connected. At the same time, when the monitoring temperature of the first temperature control component is lower than the set value of 30°C, the solid-state relay signal node is connected. That is, the solid-state relay signal node of the first temperature control component and the low temperature threshold alarm output port of the second temperature control component are both connected. The heating relay can smoothly obtain the excitation voltage, the relay operates and applies 220V AC voltage to the heating wire to achieve heating.

[0025] 2. When the outside temperature is higher than 1°C, the low temperature threshold alarm output port of the second temperature control component is disconnected, or the temperature detected by the first temperature control component is greater than 30°C, the solid-state relay signal node is disconnected, and the control circuit is open, the relay excitation voltage disappears, and the relay does not operate. At this time, the 220V AC voltage is also disconnected synchronously, and the heating circuit has no power and the heating is naturally interrupted.

[0026] 3. When the outside temperature fluctuates repeatedly in winter, the control circuit also repeatedly switches on and off to achieve automatic control. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the electrical circuit of an embodiment of the present utility model. DETAILED DESCRIPTION

[0028] The following is further described in detail through specific implementation methods:

[0029] The reference numerals in the drawings of the specification include: first thermostat 11, first temperature input port 111, solid-state relay port 112, first temperature measuring element 12, second thermostat 21, second temperature input port 211, alarm output port 212, second temperature measuring element 22, heating relay 3, and heating unit 4.

[0030] Example 1

[0031] Example 1 is basically as shown in the attached Figure 1 As shown, Figure 1 The heating control device shown in the figure automatically starts and stops by natural temperature changes, including a heating component and a temperature control unit. The heating component includes an insulation layer and a heating component. The insulation layer is coated on the outside of the guide tube. The heating component includes a heating part 4 and a heating relay 3. In this embodiment, the heating part 4 is a heating wire. The heating wire can be set in the guide tube, on the inner wall of the guide tube, or wrapped around the outer wall of the guide tube to heat the fluid in the guide tube. Preferably, the heating part 4 is wrapped around the outer wall of the guide tube to avoid corrosion of the heating part 4 by the fluid in the guide tube, and to facilitate maintenance and replacement of the heating part 4. The heating relay 3 includes an excitation end, a normally open end, and a common end. When installed, as shown in FIG. Figure 1As shown, the common end of the heating relay 3 is connected to one end of the 220V AC power supply, the upper end of the heating wire is connected to the other end of the 220V AC power supply, and the lower end is connected to the normally open end of the heating relay 3. When the excitation end is energized, the normally open end is closed, the heating wire is energized, and the fluid in the guide tube is heated.

[0032] The temperature control unit includes a first temperature control component and a second temperature control component. Figure 1 As shown, the first temperature control assembly includes a first temperature controller 11 and a first temperature measuring element 12. The first temperature controller 11 integrates temperature input and solid-state relay functions, and is provided with a first temperature input port 111 and a solid-state relay port 112. The first temperature measuring element 12 includes a connecting line and a temperature measuring part. The temperature measuring part is located between the interlayer between the guide tube and the insulation layer, and is used to measure the temperature between the guide tube and the insulation layer. The temperature measuring part is connected to the first temperature input port 111 through a connecting line, thereby transmitting the temperature signal detected by the first temperature measuring element 12 to the first thermostat 11. In this embodiment, the model of the first temperature measuring element 12 is PT100.

[0033] The second temperature control assembly includes a second temperature controller 21 and a second temperature measuring element 22. The second temperature controller 21 integrates temperature input and alarm output functions, and is provided with a second temperature input port 211 and an alarm output port 212. The second temperature measuring element 22 is of the same model as the first temperature measuring element 12. The difference is that the detection part of the second temperature measuring element 22 is placed in the environment where the diversion tube is located, and is used to measure the natural temperature of the environment where the diversion tube is located, and input the detected temperature into the second temperature controller 21 through the second temperature input port 211.

[0034] The specific implementation process is as follows:

[0035] Materials preparation: prepare two TE4-SB10W thermostats respectively. The TE4-SB10W thermostat has solid-state relay and alarm output contact functions, a 48VDC relay, and two PT100 temperature measuring elements; two meters of ordinary two-color wire, and prepare the temperature signal introduction cable according to the actual situation. Wrap the heating wire around the outer wall of the guide tube, and cover the heating wire with an insulation layer to ensure that both ends of the heating wire are outside the insulation layer. At the same time, place the detection part of a PT100 temperature measuring element in the interlayer between the insulation layer and the guide tube as the first temperature measuring element 12, and the other as the second temperature measuring element 22.

[0036] Assembly: As Figure 1As shown, a thermostat with a model of TE4-SB10W is used as the first thermostat 11 and the second thermostat 21 respectively, the positive end of the solid-state relay output signal of the first thermostat 11 is introduced into the positive end of the alarm output of the second thermostat 21, and the negative end of the alarm output of the second thermostat 21 is led out and connected to the positive end of the excitation end of the heating relay 3. Finally, the negative end of the relay is connected back to the negative end of the solid-state relay output signal of the temperature controller inside the insulation material to form a control loop. Subsequently, the first temperature measuring element 12 is connected to the first thermostat 11, and the second temperature measuring element 22 is connected to the second thermostat 21. Finally, the live wire of the 220V AC power supply is connected to the normally open end of the heating relay 3, one end of the heating part 4 is connected to the neutral wire of the 220V AC power supply, and the other end is connected to the normally open end of the heating relay 3. After the power is turned on, the following is obtained. Figure 1 The electrical connection circuit is shown.

[0037] During use: When the outside temperature is lower than 1°C, the low temperature threshold alarm output port of the second temperature control component is connected. At the same time, when the monitoring temperature of the first temperature control component is lower than the set value of 30°C, the solid-state relay signal node is connected, that is, the solid-state relay signal node of the first temperature control component and the low temperature threshold alarm output port of the second temperature control component are both connected. The heating relay 3 can smoothly obtain the excitation voltage, the relay will operate and add 220V AC voltage to the heating part 4 to realize heating.

[0038] When the outside temperature is higher than 1°C, the low temperature threshold alarm output port of the second thermostat 21 is disconnected, or the temperature detected by the first temperature control component is greater than 30°C, and the solid-state relay signal node is disconnected. At this time, the control circuit is open, the relay excitation voltage disappears, and the relay does not operate. At this time, the 220V AC voltage is also disconnected synchronously, and the heating part 4 has no electricity and the heating is naturally interrupted.

[0039] When the outside temperature fluctuates repeatedly, the control circuit is also repeatedly opened and closed to achieve automatic control.

[0040] Example 2

[0041] Example 2 is essentially the same as Example 1, differing in that it also includes a control box. In this embodiment, the control box has dimensions of 200 mm (length, width, and height) by 100 mm (length, width, and height). The control box is provided with an inner door and a slide. In this embodiment, the inner door is a mounting plate hinged within the control box. Two symmetrically arranged square holes are provided on the mounting plate for the thermostats, one for the first thermostat 11, and the other for the second thermostat 21. A slide, approximately 15 mm in size, is provided on the inner sidewall of the control box for the heating relay 3. During installation, the connecting wires can be routed behind the inner door, facilitating wiring and keeping the control box tidy. Simultaneously, the first thermostat 11, the second thermostat 21, and the heating relay 3 are installed within the control box, while the second temperature measuring element 22 is fixed to the outside of the control box. When in use, the control box can be directly moved to its installation location. The heating unit 4 need only be mounted on the guide tube, and the first temperature measuring element 12 within the control box placed between the guide tube and the insulation layer to complete the arrangement of the heating control device.

[0042] The above is only an embodiment of the present invention, and common knowledge such as the well-known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that the technical means for solving the problems in the above-mentioned embodiments of the present invention can be used in combination to solve multiple technical problems at the same time. For those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A heating control device that automatically starts and stops based on natural temperature changes, characterized by: It includes a heating component and a temperature control unit. The heating component includes an insulation layer and a heating element. The insulation layer is wrapped around the guide tube. The heating element includes a heating part and a heating relay. The heating part is arranged between the guide tube and the insulation layer and is electrically connected to the heating relay. The heating relay includes a normally open end and a relay excitation end, and the normally open end is connected to a power supply; the temperature control unit includes a first temperature control component for completing the temperature measurement and control of the interlayer between the guide tube and the insulation layer and a second temperature control component for measuring and controlling the real-time ambient temperature; the first temperature control component is a temperature controller with a solid-state relay, and the second temperature control component is a temperature controller with a low temperature threshold alarm output port; the low temperature threshold alarm output port, the solid-state relay and the relay excitation end are connected in series in sequence to form a control loop, and the first temperature control component and the second temperature control component are both provided with alarm values. When the measured temperatures are both lower than the alarm values, the control loop is connected.

2. The heating control device according to claim 1 that automatically starts and stops according to natural temperature changes is characterized in that: The first temperature control component is connected to a temperature measuring element. The temperature measuring element includes a detection part. The detection part is fixedly arranged in the interlayer between the guide tube and the insulation layer.

3. The heating control device according to claim 2 that automatically starts and stops depending on natural temperature changes is characterized by: The first temperature control component is provided with a temperature input port, and the temperature input port is communicated with the temperature measuring element.

4. The heating control device according to claim 3 that automatically starts and stops depending on natural temperature changes is characterized in that: The power supply is 220V AC.

5. The heating control device according to claim 4 that automatically starts and stops depending on natural temperature changes is characterized in that: The utility model also comprises a control box, which is provided with an inner door. Two square holes for fixing and installing a thermostat are symmetrically opened side by side on the inner door.

6. The heating control device according to claim 5 that automatically starts and stops depending on natural temperature changes is characterized in that: The inner wall of the control box is provided with a slide groove for installing the heating relay.

7. The heating control device according to claim 1 that automatically starts and stops according to natural temperature changes, characterized in that: The warning value of the first temperature control component is 30°C, and the warning value of the second temperature control component is 1°C.

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