Compact high-precision intelligent fast detector for hot galvanizing liquid based on LIBS (Laser-induced Breakdown Spectroscopy) technology

Abstract

The invention relates to an LIBS technology-based compact high-precision intelligent fast detector for hot galvanizing liquid, which comprises a detection module, an online detection positioning device, an electrical control device and a detection device.Aiming at the problems of poor repeatability, difficulty in maintenance, low safety coefficient, low detection precision and the like, the device is composed of hardware, software, control, gas media and the like of an LIBS instrument, so that the detection precision is improved; the device realizes high-precision control of zinc alloy liquid components and zinc pot liquid level, has the characteristics of accurate positioning, simplicity in installation, high repetition precision, convenience in maintenance, long service life and high safety coefficient, realizes big data analysis in the production process, and greatly improves the surface quality of a galvanized sheet.

Description

Technical Field

[0001] This patent application belongs to the field of on-site analysis and process monitoring technology in the metallurgical field. More specifically, it relates to a compact, high-precision, intelligent rapid detection instrument for hot-dip galvanizing liquid based on LIBS technology. Background Art

[0002] Hot-dip galvanizing is one of the oldest corrosion protection methods for metallurgical materials. It achieves this goal by protecting the iron cathode with a sacrificial zinc anode. Hot-dip galvanized products feature low production costs, mature technology, long service life, and excellent processing properties. They are widely used in the automotive, home appliance, building materials, photovoltaic, livestock, and other manufacturing industries, and are a major low-carbon, environmentally friendly green steel material. Currently, there are approximately 1,800 galvanizing lines in operation worldwide, with an annual production capacity of 300 million tons. The core process of galvanizing is the stable control of the zinc bath composition, which directly affects the quality and stability of the product. Therefore, the ability to efficiently and effectively monitor the zinc bath composition is crucial.

[0003] The current hot-dip galvanizing process generally uses manual sampling combined with ICP or X-ray equipment to control the zinc liquid composition. The indicators are single, the detection efficiency is low, the investment cost is high, and the feedback of the results is not timely. This leads to poor product quality stability and increased zinc consumption. Enterprises suffer economic losses such as quality degradation, increased costs, and low selling prices.

[0004] Laser Induced Breakdown Spectroscopy (LIBS) is an analytical technique used to analyze the elements and their contents in substances. It does not require complex sample pretreatment and can analyze multiple elements simultaneously, and can be used for rapid, remote, and online analysis.

[0005] In the prior art, Patent No. 2022112475576 ​​proposes a method and system for detecting the composition of hot-dip galvanizing liquid based on LIBS technology. It describes in detail the method and steps for real-time determination of the composition of hot-dip galvanizing by inserting a detection tube into the zinc liquid after building a high-precision model, but does not describe in detail the probe insertion, removal, and stabilization working process, as well as the detailed control process of gas, flow, and pressure.

[0006] Faced with the harsh working conditions of the galvanizing production line, real-time monitoring and precise analysis of zinc liquid composition with simple installation, precise positioning, high repeatability and easy maintenance are urgently needed. Summary of the Invention

[0007] The technical problem addressed by this invention is to provide a compact, high-precision hot-dip galvanizing rapid testing instrument based on LIBS technology. This instrument addresses the following technical issues currently encountered with LIBS equipment in hot-dip galvanizing bath composition detection: low detection accuracy due to inaccurate positioning; complex installation and difficult maintenance; low repeatability, making it difficult to adapt to harsh operating conditions; and the lack of dynamic liquid level feedback and a safety interlock mechanism. By integrating a high-precision conical seal coupling system, a dynamic liquid level intelligent feedback system, multi-directional flow field cooling efficiency enhancement technology, and a modular maintenance architecture, this invention achieves high-precision detection of zinc bath composition (±0.03%) and precise control of liquid level fluctuations (±0.5mm), while significantly improving the device's reliability and service life.

[0008] In order to solve the above problems, the technical solution adopted by the present invention is: A compact, high-precision, hot-dip galvanizing liquid intelligent rapid inspection instrument based on LIBS technology includes a detection module, an online detection and positioning device, an electrical control device, and a detection device. The electrical control device, the online detection and positioning device, and the detection module are connected in sequence. The electrical control device is also connected to the detection module. The detection device is connected to the detection module, and the detection device extends into the zinc pot.

[0009] The online detection and positioning device includes a lifting mechanism and a rotating mechanism. The lifting mechanism is connected and fixed to the installation floor of the on-site zinc pot by welding. The rotating mechanism is slidably installed on the lifting mechanism. The detection module is installed on the rotating mechanism. The detection module matches the zinc pot below, and the probe of the detection module enters the zinc pot. It can be seen that the detection module is adjusted by the lifting mechanism and the rotating mechanism to realize the process of online real-time detection of the detection module in the zinc pot. The structure is simple, ensures the real-time measurement, eliminates safety hazards, and improves the accuracy of the detection module.

[0010] The detection module includes a laser, an optical path box, a spectrometer, an industrial computer, and a connecting frame. The laser, optical path box, spectrometer and industrial computer are installed on the connecting frame according to the direction of the optical path. The laser is fixedly installed above the connecting frame, the optical path box is fixedly installed on the front side of the connecting frame, the spectrometer and the industrial computer are fixedly installed below the connecting frame, and the laser of the laser and the optical element of the optical path box are coaxial; the detection module is fixed on the connecting frame, and the connecting frame is connected to the rotating mechanism of the online detection and positioning device.

[0011] The laser, optical path box, spectrometer and industrial computer are communicated and connected.

[0012] The detection device includes a permanent light window, a replaceable light window, a conical structure connector, a fastening sleeve, and a detection tube. The permanent light window is tightly fixed below the optical path box and fixed above the connecting frame. The replaceable light window is rotatably installed on the top of the conical structure connector through an embedded thread, and the lower end is connected to the detection tube through a thread. The conical structure connector is fixedly connected to the bottom thread of the detection module through the fastening sleeve, and the replaceable light window is installed at a certain inclination angle to the end face of the conical structure connector.

[0013] Furthermore, the detection module also includes a gas flow controller and a gas pressure sensor. The gas flow controller is located inside the electrical control device, and the gas pressure sensor is located inside the detection module. The protective gas injected into the detection tube is argon. The gas flow controller and the gas pressure sensor control the argon and measure the liquid level information under different pressures in real time; the gas flow controller and the gas pressure sensor are both communicatively connected to the spectrometer and the industrial computer.

[0014] Furthermore, the detection module is cooled by a cooling gas, which uses compressed air, but can also be nitrogen or other cooling gases. The patented gas circuit has two signal paths: one for argon and one for compressed air. A flow field distributor is provided within the detection module. When compressed air is used as the cooling gas, the flow field distributor is limited to flow field distribution for compressed air. If nitrogen is used as the cooling gas, the flow field distributor distributes flow field for nitrogen. The flow field distributor enables oblique upward and horizontal blowing of the cooling gas, thereby optimizing the flow field of the cooling gas and improving the cooling efficiency within the detection module.

[0015] Regarding the flow field distributor, this patent is mainly used for the distribution of cooling gas airflow, mainly for compressed air distribution, so as to achieve the optimal cooling effect on all parts of the module.

[0016] Furthermore, the connecting frame is fixedly connected to the rotating mechanism of the online detection and positioning device through a rigid coupling.

[0017] Furthermore, the conical structural connector adopts conical surface centering and sealing to ensure that the optical path and the center of the detection tube are highly coincident; the conical surface sealing angle of the conical structural connector is 60° and the coaxiality deviation is ≤0.1mm, realizing the integration of air tightness and optical path centering.

[0018] Furthermore, the spectrometer and industrial computer, gas flow controller, and gas pressure sensor are safety-interlocked. The spectrometer and industrial computer are also safety-interlocked with the equipment temperature collector. If the gas flow controller, gas pressure sensor, and equipment temperature collector exceed the threshold, the safety interlock is activated, and the spectrometer and industrial computer trigger the matching servo motor. The servo motor controls the lifting, lowering, and rotation of the lifting mechanism in the detection module through the electrical control device, automatically lifting the instrument, improving the safety of the instrument and extending the service life of the instrument.

[0019] Furthermore, the detection tube is made of alumina ceramics, has an inner diameter of 8 mm, a wall thickness of 2 mm, and a temperature resistance of ≥1000°C, and is tilted and immersed under the zinc pot liquid surface to ensure that argon gas can smoothly emerge from the detection tube.

[0020] Further, the following steps are included: S1, increase the gas flow controller to ensure a large flow of argon purge; slowly immerse the probe tube into the zinc liquid in the zinc pot, and ensure that there is a suitable positive pressure inside the tube during the immersion process. The suitable positive pressure is also a large positive pressure, so that the zinc liquid will not penetrate into the inside of the probe tube, ensuring that the inner wall of the probe tube is clean; if the gas flow is small or the probe tube is inserted too quickly, the inner wall of the probe tube will solidify and be covered with zinc slag, affecting the transmission efficiency of the laser and excited plasma signals; S2, after the detection tube reaches the working position, observe the amount of argon bubbles emerging from the detection tube and adjust the gas flow controller to ensure that the number and shape of bubbles are uniform and moderate, that is, the bubbles are of uniform shape; argon gas enters the detection tube, squeezing the zinc liquid out of the detection tube orifice, ensuring that the zinc liquid level at the detection tube is exactly at the detection tube orifice; if the flow rate of the gas flow controller is large, the number of bubbles is too many, the bubbles are not formed, and the pit is too deep; if the flow rate of the gas flow controller is small, no bubbles are generated, and the pressure is too low, the zinc liquid will flow into the ceramic tube and damage the equipment; S3, after the gas flow controller is adjusted and fixed, the gas pressure sensor ensures the safety interlock mechanism. If the pressure is lower than the threshold, the lifting mechanism can be controlled by the electrical control device to lift the instrument away from the zinc pot liquid surface; S4, when lifting the detection tube, the gas flow controller is adjusted as in step S1, and a large flow of argon gas passes through the detection tube. The detection tube is slowly lifted, and the gas flow controller is closed after it leaves the zinc liquid surface and reaches a safe position.

[0021] Furthermore, in S1, in "adjust the gas flow controller to ensure high-flow argon purge", the high-flow argon purge is 3L / min-10L / min; in "ensure that there is a suitable positive pressure inside the tube during the immersion of the detection tube", the suitable positive pressure is 8Kpa~15Kpa.

[0022] Furthermore, in S2, "after the detection tube reaches the working position, observe the amount of argon bubbles emerging from the detection tube and adjust the gas flow controller to ensure that the number and shape of bubbles are uniform and moderate" means that the flow rate of the gas flow controller is lowered to 0.3L / min, and the number of argon bubbles is 1 to 3 bubbles per second; In S4, the speed of slowly lifting the detection tube is 0.1m / min~0.2m / min.

[0023] Due to the adoption of the above technical solution, the beneficial effects achieved by the present invention are: In response to the actual needs of galvanizing production lines, the present invention studies a compact, high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology. It adopts a repeatable precision conical sealing coupling system, a modular maintenance architecture, a dynamic liquid level intelligent feedback system, a multi-directional flow field cooling efficiency enhancement technology, and an optical path structure with a permanent light window and a replaceable light window for easy maintenance. Against the backdrop of industrial intelligent manufacturing, intelligent analysis, and precise control, this instrument addresses the technical pain points of real-time monitoring and precise analysis of zinc liquid composition in the metallurgical galvanizing industry. By leveraging a strategy combining LIBS technology with artificial intelligence, and through key technologies such as machine learning, precise quantitative analysis, PLC precise control, and intelligent measurement and control, it helps to solve the bottleneck problem of online detection of material composition in complex and harsh industrial sites.

[0024] This rapid tester features a high-precision conical seal coupling system, employing a precision design with a 60° conical seal angle and a coaxiality deviation of ≤0.1mm. It integrates airtightness assurance and precise optical path alignment to address issues with zinc liquid leakage (leakage rate reduced by 95%) and optical path deviation (detection accuracy increased to ±0.03%) caused by traditional split-type seal structures, preventing zinc liquid splashing and contamination of the optical path. The structure supports rapid assembly and disassembly (operation time <5 minutes) and offers a repeatability accuracy of 99.8%.

[0025] Dynamic liquid level intelligent feedback system: Based on dual-modal feedback from the argon bubbling frequency (1-3 bubbles / second) and a pressure sensor (8-15kPa), it suppresses liquid level fluctuations (fluctuation amplitude ≤±0.5mm), increasing response speed by 50% compared to traditional displacement sensor solutions. It also integrates a temperature-pressure dual-threshold safety interlock mechanism (response time <1s) to ensure that the equipment automatically rises out of the zinc liquid (lifting speed 5mm / s) in the event of an abnormality, avoiding the risk of detection tube blockage and ensuring a stable and reliable safety interlock.

[0026] The multi-directional flow field cooling efficiency enhancement technology features a compressed air flow field distributor that achieves dual-path cooling (1:2 airflow ratio) via a Y-shaped diverter cavity (flow distribution error ≤ 5%) and adjustable guide plates (angle ±15°). This reduces the laser temperature rise by 30% in a 500°C zinc bath, filling a gap in high-temperature adaptive cooling technology for LIBS equipment. A modular maintenance architecture combines a replaceable optical window (extending the replacement cycle to 3,000 times) with a permanent optical window (15° tilt), eliminating laser reflection loss and increasing energy utilization by 20%. Maintenance time is reduced from the traditional two hours to 10 minutes, extending the overall equipment life by three times. The system offers stable performance, high repeatability, and high detection accuracy, effectively ensuring the quality of galvanized sheet metal. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a schematic structural diagram of the detection module of the present invention; Figure 3 It is a partial structural diagram of the tapered structural connector of the present invention.

[0028] In the figure: detection module 1, online detection and positioning device 2, electrical control device 3, detection device 4, laser 5, optical path box 6, spectrometer and industrial computer 7, connecting frame 8, permanent light window 9, replaceable light window 10, conical structure connector 11, fastening sleeve 12, detection tube 13, gas flow controller 14, gas pressure sensor 15, zinc pot 16. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below with reference to the embodiments.

[0030] A compact and high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology, such as Figures 1 to 3 , including a detection module 1, an online detection and positioning device 2, an electrical control device 3, and a detection device 4. The electrical control device 3, the online detection and positioning device 2, and the detection module 1 are connected in sequence. The electrical control device 3 is also connected to the detection module 1. The detection device 4 is connected to the detection module 1, and the detection device 4 extends into the zinc pot 16.

[0031] The online detection and positioning device 2 includes a lifting mechanism and a rotating mechanism. The lifting mechanism is fixedly connected to the installation floor of the on-site zinc pot 16, for example, by welding. The rotating mechanism is slidably mounted on the lifting mechanism, and the detection module 1 is mounted on the rotating mechanism. The detection module 1 is matched with the zinc pot 16 below, and the probe of the detection module 1 enters the zinc pot 16. In this way, the detection module 1 is adjusted by the lifting and rotating mechanisms, realizing the process of online real-time detection of the detection module 1 within the zinc pot 16. This simple structure ensures real-time measurement, eliminates safety hazards, and improves the accuracy of the detection module 1.

[0032] The detection module 1 includes a laser 5, an optical path box 6, a spectrometer and an industrial computer 7, and a connecting frame 8. The laser 5, the optical path box 6, the spectrometer and the industrial computer 7 are installed on the connecting frame 8 according to the direction of the optical path. The laser 5 is fixedly installed above the connecting frame 8, the optical path box 6 is fixedly installed on the front side of the connecting frame 8, the spectrometer and the industrial computer 7 are fixedly installed below the connecting frame 8, and the laser of the laser 5 and the optical element of the optical path box 6 are coaxial; the detection module 1 is fixed on the connecting frame 8, and the connecting frame 8 is connected to the rotating mechanism of the online detection and positioning device 2.

[0033] The laser 5 and the optical path box 6 are communicatively connected with the spectrometer and the industrial computer 7 .

[0034] The detection device 4 includes a permanent light window 9, a replaceable light window 10, a tapered connector 11, a fastening sleeve 12, and a detection tube 13. The permanent light window 9 is tightly fixed below the optical path box 6 and fixed above the connecting frame 8. The replaceable light window 10 is rotatably mounted on the top of the tapered connector 11 via embedded threads, and the lower end is connected to the detection tube 13 via threads. The tapered connector 11 is fixedly connected to the bottom thread of the detection module 1 via the fastening sleeve 12. The replaceable light window 10 and the end surface of the tapered connector 11 are installed at a certain angle, such as 15° to 30°, or other angles are possible.

[0035] The detection module 1 also includes a gas flow controller 14 and a gas pressure sensor 15. The gas flow controller 14 is located inside the electrical control device 3, and the gas pressure sensor 15 is located inside the detection module 1. The protective gas injected into the detection tube 13 is argon. The gas flow controller 14 and the gas pressure sensor 15 control the argon and measure the liquid level information under different pressures in real time; the gas flow controller 14 and the gas pressure sensor 15 are both communicatively connected to the spectrometer and the industrial computer 7. In this way, the signals of the gas flow controller 14 and the gas pressure sensor 15 are fed back to the industrial computer for corresponding processing.

[0036] The detection module 1 is cooled by a cooling gas, which is compressed air, though nitrogen can also be used. Thus, the patented gas circuit has two signal paths: one for argon and one for compressed air. A flow field distributor is installed within the detection module 1. When compressed air is used as the cooling gas, the flow field distributor is used to distribute the compressed air flow field, and can be simply referred to as a compressed air flow field distributor. The compressed air flow field distributor achieves a portion of diagonal upward flow and a portion of horizontal flow through flow channel design, flow control, and dynamic adjustment. It utilizes multi-outlet directional flow diversion, adjustable guide vanes, and ejector technology, combined with fluid simulation optimization, to ultimately achieve precise and efficient airflow control. In a specific embodiment, the flow field distributor incorporates a built-in Y-shaped diverter cavity and adjustable guide plates, and the airflow ratio (diagonal upward: horizontal = 1:2) is adjusted by a stepper motor. The patented gas circuit has two signal paths: one for argon and one for compressed air. Compressed air generated by an air compressor is connected to the detection module 1 via an air pipe, and a compressed air flow field distributor is installed internally to achieve gas distribution and cooling.

[0037] If nitrogen is used as the cooling gas, the flow field distributor can distribute the nitrogen in the flow field, so that the flow field distributor can blow the cooling gas obliquely upward and horizontally, thereby optimizing the flow field of the cooling gas and improving the cooling efficiency inside the detection module 1.

[0038] Regarding the flow field distributor, this patent is mainly used for the distribution of cooling gas flow, mainly for compressed air distribution, so as to achieve the optimal cooling effect for all parts of the module.

[0039] The connecting frame 8 is fixedly connected to the rotating mechanism of the online detection and positioning device 2 through a rigid coupling. The rigid coupling is an existing technology and can be purchased directly.

[0040] The conical structure connector 11 adopts conical surface centering and sealing to ensure that the optical path and the center height of the detection tube 13 coincide with each other; the conical surface sealing angle of the conical structure connector 11 is 60°, the coaxiality deviation is ≤0.1mm, and the conical sealing structure is adopted to achieve the integration of airtightness and optical path centering.

[0041] The spectrometer and industrial computer 7, gas flow controller 14, and gas pressure sensor 15 are safety-linked. The spectrometer and industrial computer 7 are also safety-linked with the equipment temperature collector. If the gas flow controller 14, gas pressure sensor 15, and equipment temperature collector exceed the threshold, the safety interlock is activated, and the spectrometer and industrial computer 7 trigger the matching servo motor. The servo motor controls the lifting, lowering, and rotation of the lifting mechanism in the detection module 1 through the electrical control device 3, automatically lifting the instrument, improving the safety of the instrument and extending the service life of the instrument.

[0042] The device's temperature collector primarily collects the temperatures of the laser 5, spectrometer, and industrial computer 7. It is connected to all three. Laser 5, the laser emitting device, can be damaged or emit abnormal light if its temperature is too high or too low. The spectrometer and industrial computer 7 can also malfunction if their temperatures are too high or too low. When an abnormality occurs, the safety interlock mechanism activates, connecting the servo motor to the lifting mechanism to control the lift and rotation of the entire detection module 1.

[0043] The safety interlock mechanism specifically sets preset thresholds for various parameters. When a corresponding value exceeds the threshold, the interlock mechanism is activated, automatically raising the lifting mechanism. Electrical control device 3 controls the lifting, lowering, and rotation of the lifting mechanism. In a specific embodiment, when the gas pressure is <8 kPa or the temperature is >80°C, the industrial computer triggers the servo motor to raise the detection module 1 to a safe position (≥200 mm from the zinc liquid surface) at a speed of 5 mm / s.

[0044] At the same time, it has a dynamic liquid level feedback mechanism. The technical advantage of the above feedback mechanism is that it combines the argon bubbling frequency (1-3 / second) with the gas pressure sensor 15 to dynamically calibrate the liquid level.

[0045] The detection tube 13 is made of alumina ceramics, has an inner diameter of 8 mm, a wall thickness of 2 mm, and a temperature resistance of ≥1000°C, and is tilted and immersed under the liquid surface of the zinc pot 16 to ensure that argon gas can be smoothly emitted from the detection tube 13.

[0046] Therefore, the present invention provides a compact, high-precision, intelligent rapid detector for hot-dip galvanizing liquid based on LIBS technology, which includes the following steps: S1, increase the gas flow controller 14 to ensure a large flow of argon purge; slowly immerse the detection tube 13 into the zinc liquid in the zinc pot 16, and ensure that there is a suitable positive pressure in the tube during the immersion of the detection tube 13 (suitable positive pressure means a large positive pressure), and the zinc liquid will not penetrate into the interior of the detection tube 13, ensuring that the inner wall of the detection tube 13 is clean; if the gas flow is small or the insertion speed of the detection tube 13 is fast, the inner wall of the detection tube 13 will solidify and be covered with zinc slag, affecting the transmission efficiency of the laser and the excitation plasma signal.

[0047] In this step, "increase the gas flow controller 14 to ensure high-flow argon purge", the high-flow argon purge is 3L / min-10L / min; "ensure that there is a suitable positive pressure in the tube during the immersion of the detection tube 13", the suitable positive pressure is 8Kpa~15Kpa.

[0048] During the whole process, the flow rate of the gas flow controller 14 is adjusted to ensure the positive pressure of argon gas and prevent the zinc liquid from entering the detection tube 13. The pressure is about 15KPa when it is high and about 8KPa when it is low. Too fast insertion speed means that the acceleration is fast, and the gas pressure does not have time to exceed the liquid level differential pressure, causing the zinc liquid to enter the inside of the detection tube 13.

[0049] S2, after the detection tube 13 reaches the working position, observe the amount of argon bubbles emerging from the detection tube 13 and adjust the gas flow controller 14 to ensure that the number of bubbles and the shape are uniform and moderate, that is, the bubbles are of uniform shape; the argon gas enters the detection tube 13, squeezes the zinc liquid to emerge from the detection tube 13 port, and ensures that the zinc liquid level at the detection tube 13 is exactly at the detection tube 13 port; if the flow rate of the gas flow controller 14 is large, the number of bubbles is too many, the bubbles are not formed, and the pit is too deep; if the flow rate of the gas flow controller 14 is small, there is no bubbling, the pressure is too low, the zinc liquid will flow into the ceramic tube, and damage the equipment.

[0050] In this step, "after the detection tube 13 reaches the working position, observe the amount of argon bubbles emerging from the detection tube 13 and adjust the gas flow controller 14 to ensure that the number and shape of bubbles are uniform and moderate", which means that the flow rate of the gas flow controller 14 is lowered to 0.3L / min, the number of argon bubbles is 1 to 3 bubbles per second, or the appropriate number of bubbles is selected according to the specific situation.

[0051] The process for lowering the head in this step is as follows: When initially lowering the head, for safety reasons (to prevent the zinc liquid in the zinc pot from entering the detection tube), increase the flow rate of the gas flow controller 14 to approximately 3L / min-10L / min. As the detection device enters the zinc pot and reaches the working depth, observe the bubbling. Once it stabilizes, lower the flow rate of the gas flow controller 14 to approximately 0.3L / min. As the detection tube 13 is immersed in the zinc liquid, the gas flow controller 14 monitors the overall gas flow inside the detection tube 13. S3, after the gas flow controller 14 is adjusted and fixed, the gas pressure sensor 15 ensures the safety interlocking mechanism. If the pressure is lower than the threshold, the lifting mechanism can be controlled by the electrical control device 3 to lift the instrument away from the zinc pot 16 liquid surface.

[0052] S4: When raising the detection tube 13, adjust the gas flow controller 14 as in step S1. A large flow of argon gas is passed through the detection tube 13. The detection tube 13 is slowly raised until it is clear of the zinc liquid surface and reaches a safe position. The gas flow controller 14 is then closed. The speed of slowly raising the detection tube 13 is 0.1 m / min to 0.2 m / min, or other slow speeds are acceptable. Example

[0053] Figure 1 A schematic structural diagram of the present invention is provided, as shown in FIG. Figure 1 As shown, the compact, high-precision, intelligent rapid detector for hot-dip galvanizing baths based on LIBS technology consists of a detection module 1, an online detection and positioning device 2, an electrical control device 3, and a detection device 4. Patent 202420486890.0 details the online detection and positioning device and its connection to the detection module. Patent 2022112475576 ​​details a method and system for hot-dip galvanizing bath composition detection based on LIBS technology, as well as the connection between the electrical control device 3, the online detection and positioning device 2, and the detection module 1.

[0054] Furthermore, the online detection and positioning device 2 includes a lifting mechanism, a rotating mechanism, and the detection module 1. The lifting mechanism is connected and fixed to the installation floor of the on-site zinc pot 16 by welding. The rotating mechanism is slidably mounted on the lifting mechanism. The detection module 1 is mounted on the rotating mechanism. The detection module 1 matches the zinc pot 16 below, and the probe of the detection module 1 enters the zinc pot 16. The detection module 1 is adjusted by the lifting and rotating mechanisms, realizing the process of online real-time detection of the detection module 1 in the zinc pot 16. This simple structure ensures the real-time measurement, eliminates safety hazards, and improves the accuracy of the measurement module.

[0055] Figure 2 A schematic diagram of the detection module structure of the present invention is given, as shown in FIG. Figure 2 As shown, the above-mentioned compact high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology, the detection module 1 includes a laser 5, an optical path box 6, a spectrometer and an industrial computer 7, and a connecting frame 8. The laser 5 is fixedly installed above the connecting frame 8, the optical path box 6 is fixedly installed on the front side of the connecting frame 8, and the spectrometer and the industrial computer 7 are fixedly installed below the connecting frame 8.

[0056] Figure 3 A schematic diagram of the structure of the conical structure connector of the present invention is given, as shown in FIG. Figure 2 、3 As shown, the above-mentioned compact, high-precision, hot-dip galvanizing liquid intelligent rapid detector based on LIBS technology, the detection device 4 includes a permanent light window 9, a replaceable light window 10, a tapered structural connector 11, a fastening sleeve 12, and a detection tube 13. The permanent light window 9 is tightly fixed below the optical path box 6 and fixed above the connecting frame 8. The tapered structural connector 11 has an embedded thread at the top for rotatably mounting the replaceable light window 10, and the lower end is threadedly connected to the detection tube 13. The tapered structural connector 11 is threadedly fixed to the bottom of the detection module 1 via the fastening sleeve 12.

[0057] Furthermore, the conical connector 11 utilizes a conical surface for centering and sealing, ensuring that the optical path and the center of the detector tube 13 are highly aligned, accurately positioning the detector tube 13 and ensuring high repeatability during installation and disassembly. The conical connector 11 integrates the air path and centering within a single conical connector, resolving the conflict between sealing and centering through the combination of the conical surface and the conical hole. The gas seal prevents splashing of zinc liquid from contaminating the focusing lens. This rapid tester features a high-precision conical sealing coupling system, employing a precision design with a 60° conical sealing angle and a coaxiality deviation of ≤0.1mm. This system integrates airtightness assurance and precise optical path centering, addressing issues with zinc liquid leakage (reducing leakage rate by 95%) and optical path offset (increasing detection accuracy to ±0.03%) caused by traditional split-type sealing structures. It also prevents splashing of zinc liquid from contaminating the optical path. The structure supports rapid assembly and disassembly (operation time <5 minutes) and achieves a repeatability accuracy of 99.8%.

[0058] Furthermore, the replaceable light window 10 is combined with the permanent light window 9 to improve the convenience of equipment maintenance. During maintenance, there is no need to remove the casing, and only the replaceable light window 10 needs to be replaced.

[0059] Furthermore, the replaceable optical window 10 is installed at an angle to the end surface of the tapered connector 11. This angle prevents reflected light from damaging the laser 5, extending the lifespan of the optical components and instrument. The modular maintenance architecture combines the replaceable optical window 10 (with a replacement cycle extended to 3,000 times) with the tilted design of the permanent optical window 9 (at a 15° angle), eliminating laser reflection loss (increasing energy utilization by 20%) and reducing maintenance time from the traditional two hours to 10 minutes, extending the overall lifespan of the equipment by three times.

[0060] Furthermore, the detection tube 13 is dipped obliquely below the zinc pot liquid surface to ensure that the argon gas can smoothly emerge from the detection tube 13 .

[0061] The detection module of the compact, high-precision, intelligent rapid detector for hot-dip galvanizing liquid based on LIBS technology also includes a gas flow controller 14 and a gas pressure sensor 15. The gas flow controller 14 is located within the electrical control device 3, and the gas pressure sensor 15 is located within the detection module 1. Argon shielding gas is injected into the detection tube 13. The gas flow controller 14 and gas pressure sensor 15 control the argon gas flow and display the liquid level information at different pressures in real time.

[0062] The above-mentioned compact, high-precision hot-dip galvanizing liquid intelligent rapid detector based on LIBS technology, the detection module 1 also has a dynamic liquid level intelligent feedback system: based on the dual-modal feedback of the argon bubbling frequency (1-3 bubbles / second) and the gas pressure sensor 15 (8-15kPa), it realizes liquid level fluctuation suppression (fluctuation amplitude ≤±0.5mm), and the response speed is increased by 50% compared with the traditional displacement sensor solution. At the same time, it integrates a temperature-pressure dual-threshold safety interlock mechanism (response time <1s) to ensure that the equipment automatically lifts out of the zinc liquid (lifting speed 5mm / s) in the event of an abnormality, avoiding the risk of detection tube blockage and ensuring stable and reliable safety interlock.

[0063] The compact, high-precision, intelligent rapid detector for hot-dip galvanizing liquids based on LIBS technology utilizes compressed air or nitrogen for cooling the detection module. A compressed air flow field distributor is added, with one portion blowing diagonally upward and another blowing horizontally. This optimizes the cooling gas flow field and improves cooling efficiency within the detection module 1. Multi-directional flow field cooling efficiency enhancement technology, with the compressed air flow field distributor utilizing a Y-shaped diverter cavity (flow distribution error ≤ 5%) and an adjustable guide plate (angle ±15°), achieves dual-path cooling (1:2 airflow ratio) – diagonal upward and horizontal – in a 500°C zinc liquid environment. This reduces the laser temperature rise by 30% and improves laser operating stability by 20% in a 500°C zinc liquid environment.

[0064] In the above-mentioned compact, high-precision, hot-dip galvanizing liquid intelligent rapid detector based on LIBS technology, the detection module 1 is cooled by compressed air (or nitrogen). A compressed air flow field distributor is added, with one part blowing obliquely upward and the other part blowing horizontally, thereby optimizing the flow field of the cooling gas and improving the cooling efficiency inside the detection module 1.

[0065] The above-mentioned compact, high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology has cables and air pipe connectors placed at the rear of the instrument, which solves the bending problem at the top of the instrument, effectively reduces the height of the instrument, makes the pipeline less likely to bend and be damaged, and has a more compact structure and increased service life.

[0066] The above-mentioned compact, high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology is equipped with a safety interlock mechanism. If the device temperature collected by the gas flow controller 14, gas pressure sensor 15, and device temperature collector exceeds the threshold, the safety interlock mechanism will be activated and the instrument will be automatically lifted, thereby improving the safety of the instrument and extending the service life of the instrument.

[0067] In the aforementioned compact, high-precision, intelligent rapid detector for hot-dip galvanizing liquid based on LIBS technology, the first insertion of the detection tube into the zinc bath comprises the following steps: Step 1: Increase the gas flow controller 14 to ensure a high-flow argon purge. Slowly immerse the probe tube 13 into the zinc solution to maintain a high positive pressure. This prevents the zinc solution from entering the probe tube 13 and keeps the inner wall of the probe tube 13 clean. If the gas flow is too low or the probe tube 13 is inserted too quickly, the inner wall of the probe tube 13 may solidify and become covered with zinc slag, affecting the efficiency of laser and plasma signal transmission.

[0068] Step 2: After the probe tube 13 reaches its working position, the gas flow controller 14 is adjusted to ensure the appropriate number and shape of bubbles. Argon gas enters the probe tube 13, forcing the zinc liquid out of the opening. The zinc liquid level at the probe tube 13 is precisely positioned at the opening. If the gas flow controller 14 flows too much, bubbles will form too frequently, resulting in poorly formed bubbles and deep depressions. If the gas flow controller 14 flows too little, bubbles will not form, and the pressure will be too low, causing the zinc liquid to flow into the ceramic tube and damage the equipment.

[0069] Step 3: After the gas flow controller 14 is adjusted and fixed, the gas pressure sensor 15 ensures a safety interlock mechanism. If the pressure is lower than the threshold, the instrument can be lifted off the zinc pot 16 liquid surface.

[0070] Step 4: When lifting the detection tube 13, increase the gas flow controller 14, allow a large flow of argon to pass through the detection tube 13, slowly lift the detection tube 13, and close the gas flow controller 14 after leaving the zinc liquid surface and reaching a safe position.

[0071] Furthermore, the gas pressure sensor 15 detects the real-time pressure and interlocks the system safety; the gas flow controller 14 provides real-time feedback of the liquid level information, and can maintain and lock after adjusting a certain flow rate.

[0072] Furthermore, the argon bubbling state is adjusted, and it is more reasonable to emit 1-3 bubbles per second to ensure that the zinc liquid level fluctuates at the tube mouth of the detection tube 13: when the external zinc liquid level increases, the pressure in the tube increases, and the bubbling frequency increases; when the external zinc liquid level decreases, the pressure in the tube decreases, and the bubbling frequency decreases. In the dynamic balance, the fluctuation of the liquid level at the tube mouth 13 is ensured to be small, and at the same time, it is fed back to the gas pressure sensor 15 to dynamically detect the liquid level of the zinc pot 16.

[0073] Furthermore, the working depth of the detection tube 13 is selected based on the following criteria: the immersion depth ensures the uniformity of the hot-dip galvanizing solution; if the immersion is too shallow, there will be too much surface scum and the detection will be uneven and unrepresentative; if the immersion is too deep, the system will be subjected to too high a thermal radiation.

[0074] like Figure 3 , Figure 3 It is a partial structural diagram of the conical structural connector of the present invention. The conical surface sealing angle of the conical structural connector 11 in the present invention is 60°, and the coaxiality deviation is ≤0.1mm, realizing the integration of air tightness and optical path alignment. The conical structural connector 11 ensures the air tightness of the detection device, the high-precision centering of the optical path, and the repeatability of disassembly and assembly, thereby improving the detection accuracy of the instrument; the replaceable lens and the added tilt angle design improve the convenience of maintenance and the service life of the equipment; the modular design of the conical seal and the replaceable light window 10 solves the complex maintenance problems of the existing technology. The gas flow controller 14 and the gas pressure sensor 15 realize the safety interlock of the instrument, improve the work safety factor, and realize the dynamic liquid level feedback mechanism. The combination of the argon bubbling frequency (1-3 / second) and the gas pressure sensor 15 dynamically calibrates the liquid level, thereby improving the integration. The multi-directional airflow design of the compressed air flow field distributor fills the gap in the cooling solution of LIBS equipment in high temperature environments. The compact, high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology can detect the composition and level of zinc liquid with high precision, providing an effective guarantee for improving the quality of galvanized sheets.

Claims

1. A compact, high-precision, intelligent rapid detector for hot-dip galvanizing baths based on LIBS technology, characterized by: The invention comprises a detection module (1), an online detection positioning device (2), an electrical control device (3), and a detection device (4); the electrical control device (3), the online detection positioning device (2), and the detection module (1) are connected in sequence; the electrical control device (3) is also connected to the detection module (1); the detection device (4) is connected to the detection module (1), and the detection device (4) extends into the zinc pot (16); The online detection and positioning device (2) includes a lifting mechanism and a rotating mechanism. The lifting mechanism is fixedly connected to the installation floor of the on-site zinc pot (16). The rotating mechanism is slidably installed on the lifting mechanism. The detection module (1) is installed on the rotating mechanism. The detection module (1) matches the zinc pot (16) below. The probe of the detection module (1) enters the zinc pot (16). The detection module (1) includes a laser (5), an optical path box (6), a spectrometer and an industrial control computer (7), and a connecting frame (8). The laser (5), the optical path box (6), the spectrometer and the industrial control computer (7) are installed on the connecting frame (8) according to the direction of the optical path. The laser (5) is fixedly installed above the connecting frame (8), the optical path box (6) is fixedly installed on the front side of the connecting frame (8), the spectrometer and the industrial control computer (7) are fixedly installed below the connecting frame (8), and the laser of the laser (5) and the optical element of the optical path box (6) are coaxial. The detection module (1) is fixed on the connecting frame (8), and the connecting frame (8) is connected to the rotating mechanism of the online detection positioning device (2); The laser (5), the optical path box (6), the spectrometer and the industrial computer (7) are connected in communication; The detection device (4) includes a permanent light window (9), a replaceable light window (10), a conical structure connector (11), a fastening sleeve (12), and a detection tube (13). The permanent light window (9) is fixedly installed below the light path box (6) and fixedly installed above the connection frame (8). The top of the conical structure connector (11) is rotatably mounted with the replaceable light window (10) through an embedded thread, and the lower end is connected to the detection tube (13) through a thread. The conical structure connector (11) is fixedly connected to the bottom thread of the detection module (1) through the fastening sleeve (12); the replaceable light window (10) and the end face of the conical structure connector (11) are installed at an angle.

2. The compact, high-precision, intelligent rapid detector for hot-dip galvanizing liquid based on LIBS technology according to claim 1, characterized in that: The detection module (1) further comprises a gas flow controller (14) and a gas pressure sensor (15). The gas flow controller (14) is located inside the electrical control device (3), and the gas pressure sensor (15) is located inside the detection module (1). The protective gas injected into the detection tube (13) is argon gas. The gas flow controller (14) and the gas pressure sensor (15) control the argon gas and measure the liquid level information under different pressures in real time. The gas flow controller (14) and the gas pressure sensor (15) are both connected to the spectrometer and the industrial control computer (7) for communication.

3. The compact high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology according to claim 2 is characterized by: The detection module (1) is cooled by cooling gas, which uses compressed air. A flow field distributor is provided inside the detection module (1), and the flow field distributor enables the cooling gas to blow obliquely upward and horizontally, thereby optimizing the flow field of the cooling gas and improving the cooling efficiency inside the detection module (1).

4. The compact high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology according to claim 1 is characterized by: The connecting frame (8) is fixedly connected to the rotating mechanism of the online detection and positioning device (2) via a rigid coupling.

5. The compact high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology according to claim 1 is characterized by: The conical structure connector (11) adopts conical surface centering and sealing to ensure that the optical path and the center of the detection tube (13) are highly coincident; the conical surface sealing angle of the conical structure connector (11) is 60° and the coaxiality deviation is ≤0.1mm, realizing the integration of airtightness and optical path centering.

6. The compact high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology according to claim 4 is characterized by: The spectrometer and the industrial computer (7), the gas flow controller (14), and the gas pressure sensor (15) are safety-linked. The spectrometer and the industrial computer (7) are also safety-linked with the device temperature collector. If the gas flow controller (14), the gas pressure sensor (15), and the device temperature collector exceed the threshold, the safety interlock is activated, and the spectrometer and the industrial computer (7) trigger the matching servo motor. The servo motor controls the lifting, lowering, and rotation of the lifting mechanism in the detection module (1) through the electrical control device (3), and automatically lifts the instrument, thereby improving the safety of the instrument and extending the service life of the instrument.

7. The compact, high-precision, intelligent rapid detector for hot-dip galvanizing liquid based on LIBS technology according to claim 5, characterized in that: The detection tube (13) is made of alumina ceramic, has an inner diameter of 8 mm, a wall thickness of 2 mm, and a temperature resistance of ≥1000°C, and is tilted and immersed under the liquid surface of the zinc pot (16) to ensure that argon gas can be smoothly emitted from the detection tube (13).

8. A compact, high-precision, hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology according to any one of claims 1 to 7, characterized in that: The following steps are included: S1, turn up the gas flow controller (14) to ensure a large flow of argon gas purge; slowly immerse the detection tube (13) into the zinc liquid in the zinc pot (16), ensuring that there is a suitable positive pressure in the tube during the immersion of the detection tube (13), and the zinc liquid will not penetrate into the interior of the detection tube (13), ensuring that the inner wall of the detection tube (13) is clean; S2, after the detection tube (13) reaches the working position, the amount of bubbles emitted from the detection tube (13) is observed and the gas flow controller (14) is adjusted to ensure that the number and shape of bubbles are uniform and moderate; the argon gas enters the detection tube (13), squeezes the zinc liquid to emerge from the detection tube (13) outlet, and ensures that the zinc liquid level position at the detection tube (13) is exactly located at the detection tube (13) outlet; S3, after the gas flow controller (14) is adjusted and fixed, the gas pressure sensor (15) ensures the safety interlocking mechanism. If the pressure is lower than the threshold, the lifting mechanism can be controlled by the electrical control device (3), thereby lifting the instrument away from the zinc pot (16) liquid surface; S4, when the detection tube (13) is lifted, the gas flow controller (14) is adjusted as in step S1, a large flow of argon gas passes through the detection tube (13), and the detection tube (13) is slowly lifted. After leaving the zinc liquid surface and reaching a safe position, the gas flow controller (14) is closed.

9. The compact high-precision hot-dip galvanizing liquid intelligent rapid detection instrument based on LIBS technology according to claim 8 is characterized by: In S1, "adjust the gas flow controller (14) to ensure a large flow of argon gas purge", the large flow of argon gas purge is 3L / min-10L / min; "ensure that there is a suitable positive pressure in the detection tube (13) during the immersion process", the suitable positive pressure is 8Kpa~15Kpa.

10. The compact, high-precision, intelligent rapid detector for hot-dip galvanizing liquid based on LIBS technology according to claim 8, characterized in that: In S2, "after the detection tube (13) reaches the working position, the amount of bubbles emitted from the detection tube (13) is observed and the gas flow controller (14) is adjusted to ensure that the number of bubbles and the shape of the bubbles are uniform and moderate", which means that the flow rate of the gas flow controller (14) is lowered to 0.3L / min, and the number of argon bubbles is 1 to 3 bubbles per second; In S4, the detection tube (13) is slowly lifted at a speed of 0.1 m / min to 0.2 m / min.

Images