Calibrating device and calibrating method for transverse radar liquid level meter

Abstract

The invention provides a transverse radar liquid level meter calibrating device and method, and belongs to the technical field of radar liquid level meter calibrating equipment. According to the calibrating device, through the structural design of the laser interferometer and the reflecting plate assembly at the two ends of the displacement track and the radar liquid level meter which slides on the displacement track along with the displacement table between the laser interferometer and the reflecting plate assembly, the problem that an existing calibrating method is difficult to meet the cycle requirement of army calibration is solved. The calibrating device comprises a displacement track serving as a horizontal reference surface, a laser interferometer assembly installed at the left end of the displacement track, a reflecting plate assembly installed at the right end of the displacement track, a displacement table sliding along the displacement track and a power assembly driving the displacement table to slide on the displacement track. The radar liquid level meter and the reflecting mirror set are both installed on the displacement table and slide on the displacement track along with the displacement table, the radar liquid level meter is opposite to the reflecting plate assembly, and the reflecting mirror set is opposite to the interference mirror set.

Description

Technical Field

[0001] The invention belongs to the technical field of calibration equipment for radar level gauges, and particularly relates to a calibration device and a calibration method for a lateral radar level gauge. Background Art

[0002] The radar level gauge is one of the automatic measuring instruments commonly used in grass-roots military oil depots to measure the liquid level height in the tank. It is a liquid level measuring instrument using microwave technology with an accuracy of up to 1 mm. It has the advantages of safety and reliability, high precision, no blind area, non-contact measurement, long service life, and being almost unaffected by the changes in the physical properties of the measured medium.

[0003] To ensure that the radar level gauge meets the metrological verification requirements and the measured data is valid and reliable, the used radar level gauge should be verified annually according to the requirements of its verification regulation JJG 971-2019. Currently, there are mainly two verification methods for radar level gauges inside and outside the military; one is to verify the level gauge using an artificial dipstick; the other is to verify it using a length standard device with higher accuracy, that is, the comparison method. For these two methods, it is necessary to measure the liquid level height of the medium in the container by manual measurement, use this measured value as the standard value of the liquid level, use the measured value of the radar level gauge as the test value, and judge whether the radar level gauge meets the metrological performance requirements of the metrological verification regulation by comparing the error between the standard value and the test value.

[0004] The verification tasks of the metrological verification departments of each military branch are very heavy every year. Using the above verification methods, the existing verification cycle is long with the existing strength, and it is difficult to meet the cycle requirements of the military verification. Therefore, it is very necessary to develop a radar level gauge verification system with a relatively high degree of automation. Summary of the Invention

[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a calibration device and a calibration method for a lateral radar level gauge, which are used to solve the problems that the calibration method of the radar level gauge in the prior art is less efficient, and in the face of the heavy calibration tasks of the metrological verification departments of each military branch every year, the existing calibration methods are difficult to meet the cycle requirements of the military verification.

[0006] To achieve the above purpose and other related purposes, the present invention provides a calibration device for a lateral radar level gauge, including:

[0007] A displacement track, serving as a horizontal reference plane;

[0008] A laser interferometer assembly, including a laser interferometer, an interferometer mirror group, and a reflector mirror group. The laser interferometer is installed at the left end of the displacement track, and the interferometer mirror group remains relatively stationary with the laser interferometer;

[0009] The reflector assembly is installed at the right end of the displacement track;

[0010] The displacement stage is installed between the laser interferometer and the reflector assembly and slides along the displacement track;

[0011] The power assembly drives the displacement stage to slide on the displacement track;

[0012] The radar level gauge and the mirror group are both installed on the displacement stage and slide on the displacement track along with the displacement stage. The radar level gauge faces the reflector assembly, and the mirror group faces the interferometer mirror group.

[0013] Optionally, the displacement track is a double linear guide rail composed of multiple granite guide rail segments. The granite guide rail segments are of convex structure; the displacement stage is made of granite and is of inverted concave structure, forming an air-floating guide rail structure with the guide rail segments.

[0014] Optionally, the bottom of the guide rail segment is placed on a horizontal plane through a support base. A side adjustment plate is arranged on the side of the support base. The lower part of the side adjustment plate is detachably installed on the side of the support base, and the top of the side adjustment plate abuts against the bottom of the guide rail segment.

[0015] Optionally, the laser interferometer assembly further includes a left positioning seat, a magnetic suction base, a first magnetic suction block and a second magnetic suction block;

[0016] The left positioning seat is fixedly installed at the left end of the displacement track. The magnetic suction base is fixedly installed on the left positioning seat. A first magnetic suction block is arranged on the top of the magnetic suction base, and a second magnetic suction block is arranged at the bottom of the laser interferometer;

[0017] The laser interferometer is installed on the magnetic suction base through the cooperation of the first magnetic suction block and the second magnetic suction block;

[0018] The interferometer mirror group is fixedly installed on the left positioning seat.

[0019] Optionally, the reflector assembly includes a reflector and a right fixing seat;

[0020] The right fixing seat is fixedly installed at the right end of the displacement track. The reflector is fixedly installed on the right fixing seat by means of insertion.

[0021] Optionally, the reflector is made of carbon fiber composite material and is in the shape of a circle with a diameter of 1000 mm.

[0022] Optionally, a lifting seat is installed on the displacement stage, and the radar level gauge is fixedly installed on the lifting seat.

[0023] The present invention provides a verification method for a horizontal radar level gauge, comprising the following steps:

[0024] S1: Place the radar level gauge on the displacement table, install the laser interferometer at the left end of the displacement track, and install the reflector assembly at the right end of the displacement track;

[0025] S2: The power assembly drives the displacement table to slide on the displacement track;

[0026] S3: The laser interferometer measures the distance change between the interferometer mirror group and the reflector mirror group to obtain the measurement value of the laser interferometer;

[0027] The radar level gauge measures the distance change between it and the reflector assembly to obtain the measurement value of the radar level gauge;

[0028] S4: The difference between the measurement value of each verification point of the radar level gauge during the upstroke or downstroke minus the measurement value of each verification point of the laser interferometer is divided by the range of the radar level gauge to obtain the indication error of each verification point of the radar level gauge; By comparing the indication error with the maximum allowable error of each grade of radar level gauge, determine the accuracy grade of the radar level gauge to be verified;

[0029] The hysteresis should also be measured while measuring the indication error; The absolute value of the difference between the actual values of the same verification point during the upstroke and downstroke in the same cycle of the radar level gauge is the hysteresis of the radar level gauge; The hysteresis should not exceed the absolute value of its maximum allowable error;

[0030] S5: When the verification result of the radar level gauge is qualified, generate a verification certificate; When the verification result of the radar level gauge is unqualified, generate a non-conformance notice.

[0031] As described above, the verification device and method for a horizontal radar level gauge of the present invention has at least the following beneficial effects:

[0032] 1. The calibration device for this horizontal radar level gauge is designed with laser interferometers and reflector assemblies at both ends of the displacement track, and a radar level gauge that slides on the displacement track along with the displacement stage between them. After the displacement stage moves a certain distance, the laser interferometer emits a light beam that passes through the interference mirror group, reaches the emission mirror group, and then returns to the interference mirror group, thereby measuring the moving distance of the displacement stage. The radar level gauge measures the moving distance of the displacement stage by emitting microwaves to the reflector assembly and then the microwaves returning to the radar level gauge. By comparing the measurement values of the radar level gauge and the laser interferometer, the calibration of the radar level gauge is completed. Compared with the devices used in the existing manual tape measurement method, water tank method, and water tower method, as well as other devices used in the comparison method, the overall structure of this calibration device is simple, and only one staff member is required to complete the calibration of the radar level gauge in the laboratory, with fewer personnel used and a high degree of automation, effectively shortening the inspection cycle of the radar level gauge.

[0033] 2. The calibration method for this horizontal radar level gauge requires fewer staff members when calibrating the radar level gauge compared with the existing manual tape measurement method, water tank method, and water tower method, thereby improving the degree of automation in calibrating the radar level gauge and shortening the inspection cycle of the radar level gauge. Brief Description of the Drawings

[0034] Figure 1 It shows a schematic diagram of a calibration device for a horizontal radar level gauge according to the present invention.

[0035] Figure 2 It shows a schematic diagram of the principle of manual tape measurement in the prior art.

[0036] Figure 3 It shows a schematic diagram of the laser interferometer assembly according to the present invention.

[0037] Figure 4 It shows a schematic diagram of the magnetic base according to the present invention.

[0038] Figure 5 It shows a schematic diagram of the displacement stage according to the present invention.

[0039] Figure 6 It shows a front view of the lifting seat according to the present invention.

[0040] Figure 7 It shows a flowchart of the calibration method according to the present invention.

[0041] Figure 8 It shows a framework diagram of the calibration system according to the present invention.

[0042] Description of Component Labels

[0043] Displacement track 1, guide rail section 11, support seat 12, side adjustment plate 13;

[0044] Laser interferometer assembly 2, laser interferometer 21, interferometer mirror group 22, reflector mirror group 23, left positioning seat 24, magnetic suction base 25, horizontal groove 251, first magnetic suction block 261, second magnetic suction block 262, knob seat 27, knob 28, pitching seat 29;

[0045] Reflector assembly 3, reflector 31, right fixing seat 32;

[0046] Displacement stage 4, radar level gauge 5, lifting seat 6;

[0047] Clamping seat 7, lower clamping block 71, upper clamping block 72, clamping rod 73, clamping bolt 74. Specific implementation mode

[0048] The following specific embodiments illustrate the implementation mode of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0049] Please refer to Figures 1 to 8 . It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the implementation conditions of the present invention. Therefore, they do not have technical essence. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" cited in this specification are only for the convenience of clear narration, and are not used to limit the implementation scope of the present invention. The change or adjustment of their relative relationship, without substantial change of the technical content, should also be regarded as the implementable scope of the present invention.

[0050] Before introducing the specific implementation mode of the present invention, we will further introduce the background of the calibration device, calibration system and calibration method of this horizontal radar level gauge.

[0051] The radar level gauge belongs to a general-purpose radar level gauge. It is a measuring instrument based on the time travel principle. The radar wave travels at the speed of light, and the travel time can be converted into a level signal by electronic components. The probe emits high-frequency pulses that propagate in space at the speed of light. When the pulse encounters the surface of the material, it is reflected back and received by the receiver in the instrument, and the distance signal is converted into a level signal.

[0052] At present, the main calibration methods for level gauges at home and abroad are manual tape measurement method, water tank method, comparison method, water tower method, etc.

[0053] Manual tape measurement method: Using a standard steel tape, the height of the medium in the container is measured manually to obtain the liquid level measurement value, which is used as the standard value of the liquid level. The measurement value of the liquid level gauge is used as the test value. By comparing the error between the standard value and the test value, it is judged whether the liquid level gauge meets the metrological performance requirements of the metrological verification regulations. This method can achieve on-line verification, saving verification time and not delaying the normal use of the liquid level gauge. However, since the standard device selected for this method is a standard steel tape, its accuracy is not high, which affects the application range of this method. The working schematic diagram of this method is as shown in Figure 2 shown below.

[0054] Water tank method: The equipment of this method consists of a water tank, a liquid level gauge pressure type water tank verification device, a digital pressure calibrator, etc. The verification of the liquid level gauge is carried out by simulating a liquid tank by building a water tank with a liquid level indicating device in the laboratory. The accuracy of the standard device used in the water tank method verification is relatively high. Therefore, the accuracy level of the verification result of the water tank method is relatively high, and the range of the liquid level gauge to be tested by this method is relatively wide. The water tank method is applicable to the verification of various liquid level gauges, with high reading accuracy and relatively simple operation process. However, the verification device of the water tank method is bulky, and a large amount of water and electricity are required for verification assistance, resulting in a large consumption of resources during actual operation.

[0055] Water tower method: This method is basically the same as the water tank method for verifying the liquid level gauge. Compared with the water tank method, the verification range of the water tower method is wider and it is applicable to liquid level gauges with a wider measurement range. The maximum verification range of the water tower method depends on the height of the water tower. The higher the height of the water tower, the larger the range of the liquid level gauge that can be verified. The water tower method can verify the full-range liquid level gauge, but this method requires a long verification time, has a large labor intensity for verification operations, requires a large amount of water resources during verification, causes serious waste of water resources, and it is very difficult to discharge the sewage after verification.

[0056] Comparison method: By using a length measuring instrument with relatively high accuracy as the standard device to verify and calibrate a lower-grade liquid level gauge. The same length value is measured by the standard device and the instrument to be tested. The measurement data of the standard device is used as the true value, and the measurement data of the device to be tested is used as the measurement value. The error of the device to be tested is examined to judge whether it meets the requirements of the metrological verification regulations. At present, the standard devices selected for this method mainly include a series of high-precision instruments such as laser interferometers, grating scales, and magnetic grating scales. This method is widely used.

[0057] At present, there are mainly two methods for detecting radar liquid level gauges in China. One method is to use manual tape measurement to verify the liquid level gauge, and the other method is to use a length standard device with relatively high accuracy to verify the radar liquid level gauge to be tested, that is, the comparison method.

[0058] After introducing different calibration methods for radar level gauges, we will specifically introduce the calibration device, calibration system and calibration method of the present invention through different embodiments.

[0059] The following embodiments are for illustration only and can be combined with each other, and are not limited to the contents presented in the following single embodiments.

[0060] See also Figure 1 The present invention provides a calibration device for a lateral radar level gauge, comprising:

[0061] like Figure 1 The displacement track 1 shown is used as a horizontal reference surface;

[0062] like Figure 1 and Figure 2 The laser interferometer assembly 2 shown includes a laser interferometer 21, an interferometer lens assembly 22, and a reflector lens assembly 23. The laser interferometer 21 is installed at the left end of the displacement track 1, and the interferometer lens assembly 22 remains relatively stationary with the laser interferometer 21. The laser interferometer 21 is based on the interference phenomenon of light and splits the laser beam into two beams. One beam serves as a reference beam, and the other beam is irradiated onto the object to be measured and then reflected back to form a measuring beam. When the object to be measured is displaced, the optical path of the measuring beam changes, generating interference fringes with the reference beam. By detecting changes in the interference fringes, physical quantities such as minute displacements and angle changes of the object to be measured can be accurately measured.

[0063] like Figure 1 The reflective plate assembly 3 shown is installed at the right end of the displacement track 1;

[0064] like Figure 1 and Figure 5 The displacement stage 4 shown is installed between the laser interferometer 21 and the reflector assembly 3 and slides along the displacement track 1;

[0065] A power assembly drives the displacement stage 4 to slide on the displacement track 1; the power assembly can be composed of a servo motor system and a drag chain mechanism, or a servo motor system and a pulley. The specific structure of the power assembly is not described here.

[0066] like Figure 1 、 Figure 3 and Figure 5As shown, the radar level gauge 5 and the mirror group 23 are both installed on the displacement stage 4 and slide on the displacement track 1 along with the displacement stage 4. The radar level gauge 5 faces the reflector assembly 3, and the mirror group 23 faces the interferometer mirror group 22. That is, the calibration device of this horizontal radar level gauge 5 is designed with the laser interferometer 21 and the reflector assembly 3 at both ends of the displacement track 1, and the radar level gauge 5 that slides on the displacement track 1 along with the displacement stage 4 between them. After the displacement stage 4 moves a certain distance, the laser interferometer 21 emits a light beam, which passes through the interferometer mirror group 22, reaches the transmitting mirror group and then returns to the interferometer mirror group 22, thereby measuring the moving distance of the displacement stage 4. The radar level gauge 5 measures the moving distance of the displacement stage 4 by transmitting microwaves to the reflector assembly 3 and then the microwaves return to the radar level gauge 5. By comparing the measurement values of the radar level gauge 5 and the laser interferometer 21, the calibration of the radar level gauge 5 is completed. Compared with the devices used in the manual tape measurement method, water tank method, and water tower method in the prior art, and other devices used in the comparison method, the overall structure of this calibration device is simple, and only one staff member can complete the calibration of the radar level gauge 5 in the laboratory. Fewer personnel are used, and the degree of automation is high, effectively shortening the inspection cycle of the radar level gauge 5. Thus, it solves the problem that the calibration method of the radar level gauge 5 in the prior art has low efficiency, and in the face of the heavy calibration tasks of the metrology and calibration departments of each military branch every year, the existing calibration methods are difficult to meet the cycle requirements of the military inspection.

[0067] In another embodiment, please refer to Figure 1 and Figure 5 , the displacement track 1 is a double linear guide rail, which is composed of multiple granite guide rail segments 11. Specifically, the displacement track 1 is spliced by 3 granite marble blocks each 4 meters long. The granite guide rail segment 11 is a convex structure, that is, there are two working planes up and down, so it is called a double linear guide rail to better ensure the accuracy. The displacement stage 4 is also made of granite and is an inverted concave structure, forming an air-floating guide rail structure with the guide rail segment 11. Using compressed air to generate suspension force, a non-contact air film gap is formed between the displacement stage 4 and the guide rail, thereby eliminating friction and wear, not only with smooth movement but also higher accuracy. At the same time, two motion schemes of remote control automatic operation sliding or manual wireless semi-automatic operation sliding can be realized.

[0068] In another embodiment, please refer to Figure 1 , the bottom of the guide rail segment 11 is placed on the horizontal plane through the support base 12. The side of the support base 12 is provided with a side adjustment plate 13. The lower part of the side adjustment plate 13 is detachably installed on the side of the support base 12, and the top of the side adjustment plate 13 abuts against the bottom of the guide rail segment 11. By installing different adjustment plates, the levelness of the guide rail segment 11 is finely adjusted, thereby ensuring the calibration accuracy of this calibration device.

[0069] In another embodiment, please refer to Figure 1 and Figure 3 , the laser interferometer assembly 2 further includes a left positioning seat 24, a magnetic suction base 25, a first magnetic suction block 261 and a second magnetic suction block 262.

[0070] As Figure 3 and Figure 4 shown, the left positioning seat 24 is fixedly installed at the left end of the displacement track 1, the magnetic suction base 25 is fixedly installed on the left positioning seat 24, a first magnetic suction block 261 is arranged at the top of the magnetic suction base 25, and a second magnetic suction block 262 is arranged at the bottom of the laser interferometer 21; the laser interferometer 21 is installed on the magnetic suction base 25 through the cooperation of the first magnetic suction block 261 and the second magnetic suction block 262; the interferometer mirror group 22 is fixedly installed on the left positioning seat 24; because the laser interferometer 21 is expensive, with this design, when the calibration device is not performing calibration work, the staff can conveniently and quickly remove the laser interferometer 21, put it away, so as to facilitate the management of valuable equipment.

[0071] In another embodiment, please refer to Figure 1 , the reflector assembly 3 includes a reflector 31 and a right fixing seat 32; the right fixing seat 32 is fixedly installed at the right end of the displacement track 1, the reflector 31 is fixedly installed on the right fixing seat 32 by an insertion method, after the reflector 31 is vertically inserted into the right fixing seat 32, a threaded hole can be opened on the right fixing seat 32, and then the reflector 31 and the right fixing seat 32 are fixed horizontally, so as to ensure the installation firmness of the reflector 31.

[0072] In another embodiment, please refer to Figure 1 , the reflector 31 is made of carbon fiber composite material. This material uses high-quality carbon fiber raw materials and good basic resin. The carbon fiber plate has good properties such as high tensile strength, corrosion resistance, earthquake resistance, and impact resistance; the reflection range of most existing radar level gauges 5 is within ±50 mm. To ensure that the reflector 31 can cover the radar wave range of the radar level gauge 5 and avoid echo attenuation and false signals of other obstacles, the reflector 31 in this project is designed as a circle with a diameter of 1000 mm.

[0073] In another embodiment, please refer to Figure 5 and Figure 6 , a lifting seat 6 is installed on the displacement table 4, and the radar level gauge 5 is fixedly installed on the lifting seat 6, so as to ensure that different radar level gauges 5 can be aligned with the center of the reflector 31, and ensure that the transmitting plate can cover the radar wave range of the radar level gauge 5; the lifting seat 6 can be a hand-cranked scissor lifting seat 6 as shown in the figure, or an electric hydraulic telescopic cylinder can be used to achieve the lifting function.

[0074] In another embodiment, refer to Figure 3 and Figure 4 , the laser interferometer 21 can be adjusted in pitch. Specifically, two symmetric second magnetic attraction blocks 262 are arranged at the front end of the bottom of the laser interferometer 21, and a second magnetic attraction block 262 is arranged on the midline at the rear end of the laser interferometer 21. The three second magnetic attraction blocks 262 are arranged in such a way that the stable placement of the laser interferometer 21 can be ensured; the bottom of the second magnetic attraction block 262 is hemispherical; two first magnetic attraction blocks 261 are arranged at the front end of the magnetic attraction base 25 to correspond to the two symmetric second magnetic attraction blocks 262 arranged at the front end of the bottom of the laser interferometer 21; at the position corresponding to the second magnetic attraction block 262 arranged at the rear end of the magnetic attraction base 25 and the rear end of the laser interferometer 21, no first magnetic attraction block 261 is installed, but a pitch seat 29 is installed.

[0075] As Figure 4 shown, a transverse groove 251 is opened at the rear end of the magnetic attraction base 25, a knob seat 27 is fixedly installed in the transverse groove 251, the pitch seat 29 is slidably installed on the knob seat 27, and a knob 28 is screwed into the knob seat 27 to push the pitch seat 29 to slide on the knob seat 27; as Figure 4 shown, a groove is opened in the middle of the upper part of the pitch seat 29, and this groove can be trapezoidal as Figure 4 shown, or U-shaped; the staff drives the sliding of the pitch seat 29 by rotating the knob 28, so that the second magnetic attraction block 262 is located in the groove of the pitch seat 29 or on the upper plane of the pitch seat 29, thereby realizing the pitch adjustment of the laser interferometer 21. At the same time, because the bottom of the second magnetic attraction block 262 is designed to be hemispherical, it also ensures that the entire laser interferometer 21 remains stable after the pitch adjustment; by adjusting the pitch angle of the laser interferometer 21, the laser optical path is aligned with the pitch axis of the radar level gauge 5, thereby further improving the calibration accuracy of the calibration device.

[0076] In another embodiment, refer to Figure 5, a clamping seat 7 is also installed on the lifting seat 6. The clamping seat 7 includes a lower clamping block 71 and an upper clamping block 72. The lower clamping block 71 is fixedly installed on the lifting seat 6. Clamping rods 73 are fixedly installed on both sides of the upper end of the lower clamping block 71. Clamping holes are respectively formed on both sides of the upper clamping block 72; the two clamping holes cooperate with the two clamping rods 73 respectively, so as to connect the upper clamping block 72 to the lower clamping block 71; the opposite surfaces of the lower clamping block 71 and the upper clamping block 72 are both arc-shaped and fixedly attached with rubber sleeves; after the upper clamping block 72 and the lower clamping block 71 clamp the radar level gauge 5, a clamping bolt 74 is screwed into the top of the clamping rod 73 until it abuts against the top of the upper clamping block 72, so as to lock the radar level gauge 5; through the above structural design, the clamping reliability of different radar level gauges 5 can be ensured by adjusting the shape of the upper clamping block 72 or the shape of the rubber sleeve, as well as the fine adjustment of the radar level gauge 5 in the pitching direction and the left-right direction.

[0077] In other embodiments, such as Figure 3 and Figure 5 shown, a plurality of equally spaced threaded holes are formed on the left positioning seat 24; the magnetic adsorption base 25 is fixedly installed on the left positioning seat 24 by screwing bolts into the threaded holes; a plurality of equally spaced threaded holes are formed on the displacement table 4; the lifting seat 6 is fixedly installed on the displacement table 4 by screwing bolts into the threaded holes; the installation flexibility of the magnetic adsorption base 25 and the lifting seat 6 is increased, and the staff can adjust the positions of the magnetic adsorption base 25 and the lifting seat 6 as needed. After adjustment, screwing bolts into different threaded holes can achieve the purpose of fixation.

[0078] Please refer to Figure 7 , the present invention provides a calibration method for a horizontal radar level gauge 5, including the following steps:

[0079] S1: Place the radar level gauge 5 on the displacement table 4, that is, select a suitable upper clamping block 72 and rubber sleeve according to the model of the radar level gauge 5, and then place the radar level gauge 5 between the upper clamping block 72 and the lower clamping block 71 and clamp it; install the laser interferometer 21 at the left end of the displacement track 1, and finely adjust the pitching angle of the laser interferometer 21 through the pitching seat 29, and install the reflector assembly 3 at the right end of the displacement track 1; then adjust the height of the radar level gauge 5 through the lifting seat 6 to ensure that the center of the radar level gauge 5 is aligned with the center of the lifting plate;

[0080] S2: The power assembly drives the displacement table 4 to slide on the displacement track 1;

[0081] S3: The laser interferometer 21 measures the distance change between the interference mirror group 22 and the reflector mirror group 23, and obtains the measurement value of the laser interferometer 21;

[0082] The radar level gauge 5 measures the change in the distance between it and the reflector assembly 3 to obtain the measured value of the radar level gauge 5.

[0083] S4: The difference between the measured value of each calibration point during the upstroke or downstroke of the radar level gauge 5 and the measured value of each calibration point of the laser interferometer 21 is divided by the range of the radar level gauge 5 to obtain the indication error of each calibration point of the level gauge 5. By comparing the indication error with the maximum allowable error of each grade of radar level gauge, the accuracy grade of the radar level gauge 5 to be calibrated is determined; the hysteresis should also be measured while measuring the indication error; the absolute value of the difference between the actual values of the same calibration point during the upstroke and downstroke in the same cycle of the radar level gauge 5 is the hysteresis of the radar level gauge; the hysteresis should not exceed the absolute value of its maximum allowable error.

[0084] S5: When the calibration result of the radar level gauge 5 is qualified, a calibration certificate is generated; when the calibration result of the radar level gauge 5 is unqualified, a non - qualification certificate is generated.

[0085] Where the standard value is (0.05 + 0.040×L) mm, and L is the sliding distance of the displacement table.

[0086] The calibration method of this lateral radar level gauge 5, compared with the manual tape - measurement method, water - tank method and water - tower method in the prior art, reduces the number of staff required when calibrating the radar level gauge 5 and simplifies the operation steps of the staff, thus improving the automation degree of calibrating the radar level gauge 5 and shortening the inspection period of the radar level gauge 5.

[0087] Please refer to Figure 8 , the present invention provides a calibration system for a lateral radar level gauge, including a laser interferometer data acquisition module, a radar level gauge data acquisition module, a data processing and analysis module, and a certificate generation module.

[0088] After the power assembly drives the displacement table 4 to slide a certain distance on the displacement track 1, the laser interferometer data acquisition module obtains the measured value of the laser interferometer; the radar level gauge data acquisition module obtains the measured value of the radar level gauge; the data processing and analysis module is used to calculate the difference between the measured value of the laser interferometer and the measured value of the radar level gauge to obtain the difference value; input the standard value into the data processing and analysis module; when the absolute value of the difference value is less than or equal to the standard value, the calibration result of the radar level gauge 5 is qualified; when the absolute value of the difference value is greater than the standard value, the calibration result of the radar level gauge 5 is unqualified; the certificate generation module generates a corresponding certificate according to the calibration result of the radar level gauge by the data processing and analysis module; the above design enables the staff to quickly deliver the calibration result of the radar level gauge 5 to the corresponding personnel, reducing the working hours and further shortening the inspection period of the radar level gauge 5.

[0089] In another embodiment, please refer to Figure 8, the calibration system of the horizontal radar level gauge further includes an environmental monitoring module, which monitors the surrounding environment and obtains parameters. The environmental monitoring module is a humidity sensor and a temperature sensor, which obtain the humidity and temperature of the surrounding environment and add the influencing factors of the surrounding environment to the analysis process of the measured value, further improving the accuracy of the calibration result.

[0090] In summary, through the structural design of the laser interferometers 21 and the reflector assemblies 3 at both ends of the displacement track 1, and the radar level gauge 5 that slides on the displacement track 1 along with the displacement stage 4 between the two, the calibration device of the present invention enables fewer calibration staff to be used and has a high degree of automation, effectively shortening the inspection cycle of the radar level gauge 5, and solving the problem that the calibration method of the radar level gauge 5 in the prior art has low efficiency. Facing the heavy calibration tasks of the metrology calibration departments of each military branch every year, the existing calibration methods are difficult to meet the periodic requirements of the military's calibration. Therefore, the present invention effectively overcomes the disadvantages in the prior art and has high industrial utilization value.

[0091] The above embodiments are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A calibration device for a horizontal radar level gauge, characterized in that, Comprising: A displacement track, serving as a horizontal reference plane; A laser interferometer assembly, including a laser interferometer, an interferometer mirror group, and a reflector mirror group. The laser interferometer is installed at the left end of the displacement track, and the interferometer mirror group remains relatively stationary with respect to the laser interferometer; A reflector assembly, installed at the right end of the displacement track; A displacement stage, installed between the laser interferometer and the reflector assembly, and sliding along the displacement track; A power assembly, driving the displacement stage to slide on the displacement track; Both the radar level gauge and the reflector mirror group are installed on the displacement stage and slide on the displacement track along with the displacement stage. The radar level gauge faces the reflector assembly, and the reflector mirror group faces the interferometer mirror group.

2. The calibration device for a lateral radar level gauge according to claim 1, wherein: The displacement track is a double linear guide rail, composed of multiple granite guide rail segments. The granite guide rail segments are of a convex structure; The displacement stage is made of granite and is of an inverted concave structure, forming an air-floating guide rail structure with the guide rail segments.

3. The calibration device for a lateral radar level gauge according to claim 2, wherein: The bottom of the guide rail segment is placed on a horizontal plane through a support seat. A side adjustment plate is provided on the side of the support seat. The lower part of the side adjustment plate is detachably installed on the side of the support seat, and the top of the side adjustment plate abuts against the bottom of the guide rail segment.

4. The calibration device for a lateral radar level gauge according to claim 1, wherein: The laser interferometer assembly further includes a left positioning seat, a magnetic suction base, a first magnetic suction block, and a second magnetic suction block; The left positioning seat is fixedly installed at the left end of the displacement track. The magnetic suction base is fixedly installed on the left positioning seat. A first magnetic suction block is provided at the top of the magnetic suction base, and a second magnetic suction block is provided at the bottom of the laser interferometer; The laser interferometer is installed on the magnetic suction base through the cooperation of the first magnetic suction block and the second magnetic suction block; The interferometer mirror group is fixedly installed on the left positioning seat.

5. The calibration device for a lateral radar level gauge according to claim 1, wherein: The reflector assembly includes a reflector and a right fixing seat; The right fixing seat is fixedly installed at the right end of the displacement track. The reflector is fixedly installed on the right fixing seat by an insertion method.

6. The calibration device for a lateral radar level gauge according to claim 1, wherein: The reflector is made of a carbon fiber composite material and is in the shape of a circle with a diameter of 1000 mm.

7. The calibration device for a lateral radar level gauge according to claim 1, wherein: A lifting seat is installed on the displacement stage, and the radar level gauge is fixedly installed on the lifting seat.

8. A verification method for a horizontal radar liquid level gauge, characterized in that, Including the following steps: S1: Place the radar level gauge on the displacement stage, install the laser interferometer at the left end of the displacement track, and install the reflector assembly at the right end of the displacement track; S2: The power assembly drives the displacement stage to slide on the displacement track; S3: The laser interferometer measures the distance change between the interferometer mirror group and the reflector mirror group to obtain the measurement value of the laser interferometer; The radar level gauge measures the distance change between it and the reflector assembly to obtain the measurement value of the radar level gauge; S4: The difference between the measurement value of each calibration point during the upward or downward stroke of the radar level gauge minus the measurement value of each calibration point of the laser interferometer is divided by the range of the radar level gauge to obtain the indication error of each calibration point of the radar level gauge; By comparing the indication error with the maximum allowable error of each grade of radar level gauge, the accuracy grade of the radar level gauge to be calibrated is determined; The hysteresis should also be measured while measuring the indication error; The absolute value of the difference between the actual values of the same calibration point during the upward and downward strokes in the same cycle of the radar level gauge is the hysteresis of the radar level gauge; The hysteresis should not exceed the absolute value of its maximum allowable error; S5: When the calibration result of the radar level gauge is qualified, a calibration certificate is generated; When the calibration result of the radar level gauge is unqualified, a non-conformance notice is generated.

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