A method and device for monitoring the immersion of an insulating layer

Abstract

The present application belongs to the technical field of insulation layer monitoring, and particularly relates to an insulation layer immersion monitoring device and a monitoring method, which comprises the following steps: a host computer sends a work instruction to a single-chip microcomputer; the single-chip microcomputer receives the work instruction sent by the host computer, and sends a work signal to a signal generating module and a control module; the signal generating module applies a work signal to a control module actuator; the control module amplifies the signal sent by the single-chip microcomputer in power, and drives the control module actuator; the control module actuator receives the work signal from the signal generating module and the control module, and applies a potential difference excitation signal to a conductivity monitoring electrode. The present application monitors the conductivity of the insulation layer in real time through the setting of the monitoring module and the conductivity monitoring electrode of the insulation layer, and determines the feedback value of the conductivity of the insulation layer through the setting of the control module actuator, so as to apply the potential difference excitation signal, and continuously monitor whether the insulation layer is immersed, thereby improving the determination accuracy.

Description

Technical Field

[0001] This invention belongs to the field of thermal insulation layer monitoring technology, specifically relating to a thermal insulation layer water immersion monitoring device and monitoring method. Background Technology

[0002] Currently, corrosion on the exterior of Sinopec's refining and chemical plants is quite severe, especially under the insulation layer. This can lead to equipment malfunctions, unplanned shutdowns, and leaks of hazardous substances, causing huge economic losses. In severe cases, it can even result in personal injury or death.

[0003] During the operation of the insulation layer, its conductivity dynamically changes with variations in equipment status, environment, and working conditions. When the insulation layer's conductivity is low, the resulting deviations in electrolyte current and resistance will significantly influence the electrochemical corrosion monitoring results beneath the insulation layer. Current methods for monitoring insulation layer immersion include the drying and load-bearing method using insulation material samples, distributed fiber optic technology based on the Joule-Thomson effect, and infrared thermal imaging monitoring technology. However, none of these methods can effectively compensate for the reduced conductivity of the insulation layer during monitoring. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a device and method for monitoring water immersion in thermal insulation layers.

[0005] The technical solution adopted by this invention to solve its technical problem is: a method for real-time monitoring of the immersion and conductivity of a thermal insulation layer, comprising the following steps:

[0006] S1, The host computer sends a working instruction to the microcontroller;

[0007] S2, the microcontroller receives the work instructions from the host computer and sends work signals to the signal generation module and the control module;

[0008] S3, the signal generation module applies a working signal to the control module's actuator; the control module amplifies the signal from the microcontroller and drives the control module's actuator.

[0009] S4, the control module actuator receives working signals from the signal generation module and the control module and applies a potential difference excitation signal to the conductivity monitoring electrode;

[0010] S5, the monitoring module detects the response current signal and feeds it back to the control module actuator. The control module actuator judges the response current signal and performs its work based on the judgment result, including: the control module actuator acquires the response current signal; the control module actuator compares the response current value with the set monitoring lower limit; when the response current value is less than the monitoring lower limit, the excitation signal is always applied; when the response current value is greater than the monitoring lower limit, the excitation signal is repeatedly applied every hour.

[0011] S6, the A / D conversion module acquires the analog signal from the monitoring module and converts the analog signal into a digital signal;

[0012] S7, the microcontroller acquires digital signals and uploads them to the host computer;

[0013] S8, the host computer processes the acquired digital signals.

[0014] Furthermore, the potential difference excitation signal described in S4 is 5-15mV.

[0015] Furthermore, the processing of the acquired digital signals by the host computer in S8 includes:

[0016] The resistance of the electrolytic cell is calculated by measuring the current and voltage values.

[0017] The resistance of the insulation layer is calculated by the resistance at both ends of the electrolytic cell;

[0018] The conductivity of the insulation layer is calculated by measuring its resistance.

[0019] Furthermore, a water immersion monitoring device for insulation layers includes: a host computer, a microcontroller, a signal generation module, a control module, a control module actuator, a conductivity monitoring electrode, a monitoring module, and an A / D conversion module.

[0020] Furthermore, the conductivity monitoring electrode includes an encapsulating resin, a sheet electrode disposed on the encapsulating resin, and a clamp connecting the encapsulating resin.

[0021] Furthermore, the output of the monitoring module is connected to the input of the A / D conversion module.

[0022] Furthermore, the input terminal of the microcontroller is connected to the control module, the host computer, and the A / D conversion module; the output terminal of the microcontroller is connected to the signal generation module and the control module.

[0023] Furthermore, the input end of the control module actuator is connected to the signal generation module and the control module; the output end of the control module actuator is connected to the monitoring module.

[0024] Furthermore, the output of the monitoring module is connected to the A / D conversion module.

[0025] The beneficial effects of the present invention are as follows: The present invention monitors the conductivity of the insulation layer in real time by setting a monitoring module and an insulation layer conductivity monitoring electrode, and determines the feedback insulation layer conductivity value by setting a control module actuator to apply a potential difference excitation signal to continuously monitor whether the insulation layer is soaked in water, thereby improving the accuracy of the determination. Attached Figure Description

[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Now, the present invention will be described in detail with reference to the accompanying drawings. This figure is a simplified schematic diagram, which only illustrates the basic structure of the present invention in a schematic manner, and therefore only shows the components related to the present invention.

[0027] Figure 1 This is a block diagram of the insulation layer water immersion monitoring device of the present invention;

[0028] Figure 2 yes Figure 1 A schematic diagram of the conductivity monitoring electrode of the insulation layer immersion monitoring device shown.

[0029] Figure 3 This is a partial circuit diagram of the insulation layer water immersion monitoring device of the present invention;

[0030] Figure 4 This is a flowchart of the water immersion monitoring method for the insulation layer of the present invention;

[0031] Figure 5 This is a schematic diagram of the finite element analysis results showing the influence of the shape of the insulation layer on the conductivity of the present invention.

[0032] In the picture:

[0033] 1. Host computer; 2. Microcontroller; 3. Signal generation module; 4. Control module actuator; 5. Conductivity monitoring electrode; 6. Encapsulation resin; 61. Sheet electrode; 62. Fixture; 63. Monitoring module; 7. A / D conversion module; 8. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Please see Figure 1 A real-time monitoring device for water immersion and conductivity of thermal insulation layer includes a host computer 1, a microcontroller 2, a signal generation module 3, a control module 4, a control module actuator 5, a conductivity monitoring electrode 6, a monitoring module 7, and an A / D conversion module 8.

[0036] Signal generation module 3 is the potential difference excitation signal generation circuit; monitoring module 7 is the conductivity monitoring circuit, which is a commonly used zero-ohm monitoring circuit; A / D conversion module 8 is the A / D conversion circuit; and control module actuator 5 is a commonly used relay.

[0037] See Figure 2 The conductivity monitoring electrode 6 includes an encapsulating resin 61, a sheet electrode 62 disposed on the encapsulating resin 61, and a clamp 63 connecting the encapsulating resin 61. The two sheets of encapsulating resin 61 are parallel to each other and have the same shape. The sheet electrode 62 is disposed in the encapsulating resin 61, with only one exposed working surface. Materials such as platinum, graphite, stainless steel, and titanium can be selected.

[0038] When the conductivity monitoring electrode 6 is required to work, insert the conductivity monitoring electrode 6 into the insulation layer, adjust the distance between the working surfaces of the two sheet electrodes 62 to 5mm, ensure that the space between the two sheet electrodes 62 is filled with the insulation layer, control the pressure range between the conductivity monitoring electrode 6 and the insulation layer to 10-30Pa, ensure good contact between the sheet electrodes 62 and the insulation layer and not significantly reduce the apparent density of the insulation layer in the gap.

[0039] When implementing water immersion of the insulation layer and conductivity monitoring using a conductivity monitoring device, see Figure 4 It includes the following steps:

[0040] S1, host computer 1 sends a working instruction to microcontroller 2;

[0041] S2, the microcontroller 2 receives the working instructions sent by the host computer 1 and sends working signals to the signal generation module 3 and the control module 4;

[0042] S3, after receiving the working signal from the microcontroller 2, the signal generating module 3 applies the working signal to the control module execution mechanism 5; the control module 4 amplifies the signal sent by the microcontroller 2 and drives the control module execution mechanism 5.

[0043] S4, the control module actuator 5 receives the working signal from the signal generation module 3 and the control module 4 and applies a potential difference excitation signal of 5-15mV to the conductivity monitoring electrode 6;

[0044] S5, the monitoring module 7 monitors the response current signal and feeds it back to the control module actuator 5. If the response current value is less than the monitoring lower limit, it is determined that the insulation layer is dry at this time. The control module actuator 5 always applies a potential difference excitation signal to the conductivity monitoring electrode 6. If the response current value is greater than the monitoring lower limit, the excitation signal ends when the response current value fluctuates within a range of less than ±1% within 1 second. The control module actuator 5 repeats the excitation signal every 1 hour until the response current value is less than the monitoring lower limit. On the one hand, this avoids the false capacitance effect on the electrode when the immersion volume is small and avoids the Faraday effect from changing the micro-area environment. On the other hand, after immersion, due to the baking of high-temperature pipeline equipment or the cessation of the immersion water source, the immersion volume will gradually decrease, and the conductivity needs to be monitored regularly.

[0045] The value of the monitoring lower limit mainly depends on the monitoring lower limit of the zero-ohmmeter instrument and the interference situation at the application site. In this embodiment, the value is 0.1~50 nanoamps.

[0046] S6, A / D conversion module 8 acquires the analog signal from monitoring module 7 and converts the analog signal into a digital signal;

[0047] S7, the microcontroller 2 acquires the digital signal 1 and uploads it to the host computer 1;

[0048] S8, the host computer 1 processes the acquired digital signals and outputs the conductivity of the insulation layer;

[0049] For details, see Figure 3 The amplitude of the potential difference excitation signal is U0. In the electrolytic cell composed of the sheet electrode 62 and the insulation layer under test, the compensating liquid connection resistance R... s Reaction resistance R a The insulation layer resistance R. For example... Figure 2 As shown, under the control of control module 4, the control module actuator 5 controls the closure of terminals K and a. At this time, assume the resistance across the electrolytic cell is R. x Then R x =U0 / I0.

[0050] Among them, the compensating liquid junction resistor R sThe reason for this is that the sheet electrode 62 conducts electricity through the directional movement of electrons, while solution conducts electricity through the directional movement of ions. When the sheet electrode 62 is inserted into the solution, an atomic-sized gap is created between the sheet electrode 62 and the solution. Electrochemically, this structure is called an electric double layer. Current must overcome a certain resistance to pass through this double layer; this resistance is called the liquid junction resistance, which is the compensating liquid junction resistance R in this embodiment. s .

[0051] Reaction resistance R a Also known as Faraday resistance, it is commonly used in the electrolysis of water. Hydrogen ions form hydrogen gas on the electrode surface, which involves a process of converting electrical energy into chemical energy. The resulting resistance is called reaction resistance.

[0052] The resistance R at both ends of the electrolytic cell x Including compensating liquid junction resistor R s Reaction resistance R a If the resistance of the insulation layer is R, then R = R x -R a -R s .

[0053] Determine R a With R s The process is as follows: First, cut two appropriately sized, identical insulation layers and weigh them, recording the first weighing data. Wet the two cut insulation layers, ensuring the same amount of water is used, and record the second weighing data, also determining the volumetric moisture content. Wrap the two insulation layers in plastic wrap and let them stand for 24 hours. Squeeze out some water from one of the insulation layers to obtain the leachate. Measure the conductivity of the leachate using a conductivity meter and calculate its density. Multiply the volumetric moisture content by the conductivity of the leachate to obtain the insulation layer conductivity σ. After measuring the conductivity σ, first substitute it into σ = L / (R) r A) Calculate the resistivity R of the insulation layer. r Then the resistivity R of the insulation layer r Substitute R r =f(σ, R), calculate the resistance R of the insulation layer. Measure the resistance R across the electrolytic cell using an ohmmeter. x , will R x Substitution Calculate R a +R s .

[0054] Among them, see Figure 5 The electric field of the two electrode plates as positive and negative poles was modeled and analyzed using finite element analysis software to calculate the conductivity σ of different insulation layers, and the resistivity R of different insulation layers was also analyzed. rUnder these conditions, a series of data on the resistance R of the insulation layer were measured. Data analysis software was used to couple the series of data into a function to obtain the resistivity R of the insulation layer between the 62 sheet electrodes. r The relationship between the insulation layer resistance R and the resistance R is as follows:

[0055] R r =f(σ,R) (1)

[0056] In equation (1), σ is the electrical conductivity of the insulation layer.

[0057] The electrical conductivity σ of the insulation layer and R r The relationship is:

[0058] σ=L / (R r A)(2)

[0059] In equation (2), A is the area of ​​the electrode sheet and L is the spacing between the electrode sheets.

[0060] When it is necessary to test the electrical conductivity σ of the insulation layer under specific conditions, the testing and calculation steps are as follows:

[0061] ① R measured in practice x The insulation layer resistance R is obtained. The insulation layer conductivity σ0 = 0.1 S / m is set. The insulation layer resistance R and insulation layer conductivity σ0 are substituted into equation (1) to obtain the insulation layer resistivity R. r0 ;

[0062] ②Calculate the resistivity R of the insulation layer r0 Substituting into equation (2), we obtain the electrical conductivity σ1 of the insulation layer;

[0063] ③ If σ1-σ0≥0.001S / m at this time, then repeat steps ① and ② to perform iterative calculation: Substitute σ1 into equation (1) to obtain R. r1 Then R r1 Substituting into equation (2) yields σ2. If σ2-σ1≥0.001S / m, the iterative calculation continues until σ2 is obtained. i -σ i-1 <0.001S / m, output insulation layer conductivity calculation result σ i .

[0064] In summary, this invention connects the compensation liquid to a resistor R during the monitoring process of whether the insulation layer is submerged in water. s With reaction resistance R a Taking error factors into account, the monitoring module 7 monitors the response current value in the real-time insulation layer immersion and conductivity detection device in real time. The control module actuator 5 uses the response current value to perform the next action to ensure more accurate real-time immersion of the insulation layer.

[0065] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the scope of the present invention. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A method for monitoring water immersion in a thermal insulation layer, characterized in that, Includes the following steps: S1, The host computer sends a working instruction to the microcontroller; S2, the microcontroller receives the work instructions from the host computer and sends work signals to the signal generation module and the control module; S3, the signal generation module applies a working signal to the control module's actuator; the control module amplifies the signal from the microcontroller and drives the control module's actuator. S4, the control module actuator receives working signals from the signal generation module and the control module and applies a potential difference excitation signal to the conductivity monitoring electrode; S5, the monitoring module detects the response current signal and feeds it back to the control module actuator. The control module actuator judges the response current signal and performs its work based on the judgment result, including: the control module actuator acquires the response current signal; the control module actuator compares the response current value with the set monitoring lower limit; when the response current value is less than the monitoring lower limit, the excitation signal is always applied; when the response current value is greater than the monitoring lower limit, the excitation signal is repeatedly applied every hour to maintain monitoring of the insulation layer. S6, the A / D conversion module acquires the analog signal from the monitoring module and converts the analog signal into a digital signal; S7, the microcontroller acquires digital signals and uploads them to the host computer; S8, the host computer processes the acquired digital signals.

2. The method for monitoring water immersion in a thermal insulation layer according to claim 1, characterized in that, The potential difference excitation signal described in S4 is 5-15mV.

3. The method for monitoring water immersion in a thermal insulation layer according to claim 1, characterized in that, The processing of the acquired digital signals by the host computer in S8 includes: The resistance of the electrolytic cell is calculated by measuring the current and voltage values. The resistance of the insulation layer is calculated by the resistance at both ends of the electrolytic cell; The conductivity of the insulation layer is calculated by measuring its resistance.

4. A device for monitoring water immersion in insulation layers, characterized in that, include: Host computer, microcontroller, signal generation module, control module, control module actuator, conductivity monitoring electrode, monitoring module, A / D conversion module.

5. The insulation layer immersion monitoring device according to claim 4, characterized in that, The conductivity monitoring electrode includes an encapsulating resin, a sheet electrode disposed on the encapsulating resin, and a clamp connecting the encapsulating resin.

6. The insulation layer immersion monitoring device according to claim 4, characterized in that, The output of the monitoring module is connected to the input of the A / D conversion module.

7. The insulation layer immersion monitoring device according to claim 4, characterized in that, The input terminal of the microcontroller is connected to the control module, the host computer, and the A / D conversion module; the output terminal of the microcontroller is connected to the signal generation module and the control module.

8. The insulation layer immersion monitoring device according to claim 4, characterized in that, The input end of the control module actuator is connected to the signal generation module and the control module; the output end of the control module actuator is connected to the monitoring module.

9. The insulation layer immersion monitoring device according to claim 4, characterized in that, The output of the monitoring module is connected to the A / D conversion module.

Images