Urea filling machine with quality verification function and verification method thereof

Abstract

The invention particularly relates to a urea filling machine with a quality verification function and a verification method thereof, and the urea filling machine comprises a filling main body (1) which comprises a container (11); the detection assembly (2) is arranged in the container (11); the detection assembly (2) comprises a drainage section (21), a first stop valve (22), a detector (23), a second stop valve (24) and a checker (25) which are connected in sequence, and a controller (26) for controlling the first stop valve (22), the detector (23), the second stop valve (24) and the checker (25); the detector (23) has a temperature control function and a volume measuring and calculating function, the checker (25) comprises a straight pipe section, and the straight pipe section has a friction force measuring and calculating function. The device at least has the advantages of small detection loss, accurate test, small temperature, foam and pyrolysis interference and the like.

Description

Technical Field

[0001] The invention relates to the technical field of urea solution detection, and in particular to a urea filling machine with a quality inspection function and a inspection method thereof. Background Art

[0002] Vehicle exhaust emissions will cause air pollution and environmental damage, and SCR (Selective Catalytic Reduction) technology can treat vehicle exhaust and decompose environmentally polluting nitrogen oxides into nitrogen and water, thereby reducing the pollution of vehicle exhaust emissions to the atmospheric environment.

[0003] Among them, urea solution is used to produce ammonia at high temperature, and with the support of SCR technology, ammonia and nitrogen oxides are used to produce redox reactions. Therefore, the quality (concentration) of urea solution is crucial to vehicle emissions. However, in the actual use of urea solution, if the concentration of urea solution is too low, it is easy to cause insufficient redox reaction to produce residual nitrogen oxides; and if the concentration of urea solution is too high, it is easy to cause SCR catalyst poisoning. Therefore, the use of urea solution has high requirements for its quality (concentration).

[0004] In the prior art, the urea filling machine will detect the concentration of the urea solution before filling the urea solution to ensure that the concentration of the urea solution added to the vehicle meets the use requirements. For example, patent CN210426712U discloses a vehicle urea filling machine calibration device, which mainly detects the concentration of the urea solution by an electronic scale and a density meter. Although the above device can calibrate the concentration of the urea solution, the volume mass measurement method can only measure the concentration of the urea solution at the current temperature, and it is not universal. In actual use, the concentration measurement of the urea solution is often distorted due to temperature fluctuations. Especially for low temperature conditions, since the crystallization point of urea is below zero, when the temperature is low, the urea in the urea preparation solution in the urea filling machine is partially precipitated, resulting in a situation where the detection solubility is high. At the same time, the prior art also provides an ultrasonic detection method for urea solution, but the ultrasonic wave is susceptible to the factor of urea foam, resulting in ultrasonic attenuation distortion, which in turn affects the detection accuracy. In addition, urea will be pyrolyzed at high temperature, so that the concentration of urea solution becomes lower. Therefore, the concentration of urea solution in urea filling machine is affected by many factors, including temperature, urea crystallization, foam and so on. Summary of the invention

[0005] In view of the fact that there are many factors affecting the concentration detection of urea solution in a urea filling machine in the prior art and that the solution causes detection distortion, the present invention provides a urea filling machine with quality inspection function and a inspection method thereof, which have at least the advantages of small detection loss, accurate testing, and small temperature, foam and pyrolysis interference.

[0006] First aspect

[0007] The present invention provides a urea filling machine with a quality inspection function, comprising:

[0008] Filling body, including container;

[0009] A detection component disposed in the container;

[0010] The detection assembly includes a drainage section, a first stop valve, a detector, a second stop valve and a calibrator connected in sequence, and a controller for controlling the first stop valve, the detector, the second stop valve and the calibrator;

[0011] The detector has temperature control function and volume calculation function, and the calibrator includes a straight pipe section, and the straight pipe section has a friction force calculation function.

[0012] Specifically, one of the main concepts of the present invention is to obtain the concentration of the urea solution by using temperature, volume and pressure testing methods, and to provide a calibrator after the detector for concentration calibration, thereby eliminating the influence of temperature, bubbles and pyrolysis on the urea concentration measurement, making the detection of urea concentration more accurate.

[0013] Furthermore, in terms of setting height, from high to low, they are the drainage section, the calibrator and the detector.

[0014] Furthermore, the drainage section includes a plurality of drainage tubes, and the openings of the drainage tubes are respectively arranged at different heights in the container.

[0015] Specifically, the height of each component and the structural design of the drainage section of the present invention enable the detector and the calibrator to measure only a small amount of urea solution in the container, thereby avoiding detection distortion caused by excessive detection of urea solution. At the same time, the present invention also uses a multi-point sampling method to avoid excessive sampling during the urea solution sampling process, which may result in the detection solubility being unrepresentative. Therefore, the present invention eliminates the influence of large-volume measurement of urea solution by sampling and testing urea solution at different heights, further improving detection accuracy and detection reliability.

[0016] Furthermore, the detector includes a cylindrical or square shaped accommodation cavity.

[0017] Optionally, the detector includes a heating element, a thermistor and a pressure testing element arranged in the accommodating cavity.

[0018] Specifically, the bottom area of ​​the accommodating cavity is known, and the urea solution in the detector is heated by a heating element, and the temperature of the urea solution is measured by a thermistor, and the pressure of the urea solution on the bottom area of ​​the detector is measured by a pressure testing element.

[0019] Optionally, the straight pipe section includes a friction element and a flow rate testing element.

[0020] Optionally, the detection assembly is at least partially integrated into the container.

[0021] Second aspect

[0022] The present invention provides a quality inspection method for a urea filling machine, which is used for a urea filling machine with a quality inspection function as described in any embodiment of the first aspect, and comprises the following steps:

[0023] S10, the detector obtains urea solution through the drainage section;

[0024] S20, heating the urea solution to a first preset temperature, obtaining a first pressure value and a first volume value, and calculating a first urea concentration based on the first pressure value and the first volume value;

[0025] S30, raising the temperature to a second preset temperature, synchronously acquiring a second pressure value and a second volume value, and calculating a second urea concentration based on the second pressure value and the second volume value;

[0026] S40. Obtaining a urea output concentration according to the first urea concentration and the second urea concentration.

[0027] Specifically, another main concept of the present invention is to obtain the concentration of the urea solution by measuring the temperature and volume of the urea solution, thereby avoiding eliminating the effect of temperature on the solubility of urea, making the measurement of the concentration of the urea solution more accurate.

[0028] Furthermore, the optimal dissolution temperature of urea is ≤ the first urea concentration ≤ the second urea concentration ≤ the minimum pyrolysis temperature of urea. The optimal dissolution temperature of urea is 20°C to 30°C, and the minimum pyrolysis temperature of urea is 80°C to 100°C.

[0029] Furthermore, the calculation formula for the concentration of urea solution is: Where, C is the concentration of urea solution, ρ2 is the density of pure water, which is obtained by looking up the table based on temperature, and ρ1 is the density of urea solution. P is the bottom pressure of the container, S is the bottom area of ​​the container, g is the acceleration of gravity, and V is the volume of the urea solution. That is, the first urea concentration C1 and the first urea concentration C2 can both be obtained through the above formula.

[0030] Furthermore, after step S30, the following steps are included:

[0031] S31, directing the urea solution to the straight pipe section at a preset flow rate, synchronously acquiring the pipe wall friction of the straight pipe section, and calculating a third urea concentration based on the pipe wall friction;

[0032] S32: Using the third urea concentration to calculate the urea output concentration in step S40.

[0033] Specifically, the third urea concentration is still calculated using the formula Solve for the concentration of urea solution, but the density of urea solution is Among them, Δp is the pressure loss generated when the fluid flows in the pipe, d is the pipe diameter, λ is the friction coefficient, ν is the fluid flow rate, and l is the pipe length.

[0034] Further, in step S40, the urea output concentration is processed according to the comparison relationship among the first urea concentration, the second urea concentration and the third urea concentration:

[0035] When the second urea concentration is less than the first urea concentration:

[0036] S41, determining whether the third urea concentration is less than or equal to the second urea concentration, if so, taking the first urea concentration as the urea output concentration; if not, executing step S42;

[0037] S42, determining whether there is urea crystal interference in the detector or the straight pipe section;

[0038] When the second urea concentration is equal to the first urea concentration:

[0039] S43, judging whether the third urea concentration is equal to the second urea concentration, if so, taking the third urea concentration as the urea output concentration; if not, executing step S44;

[0040] S44, taking the second urea concentration as the urea output concentration, and determining whether the third urea concentration is greater than the second urea concentration, if so, proceeding to step S45;

[0041] S45, determining whether there is urea crystallization interference in the straight pipe section;

[0042] When the second urea concentration is greater than the first urea concentration:

[0043] S46, determining whether the third urea concentration is greater than or equal to the second urea concentration, if so, taking the third urea concentration as the urea output concentration; if not, executing step S47;

[0044] S47. Using the second urea concentration as the urea output concentration.

[0045] Specifically, another main concept of the present invention is to correct the first urea concentration and the second urea concentration by a third urea concentration, so as to avoid the interference of solubility on the urea measurement accuracy.

[0046] In summary, the present invention provides a urea filling machine with quality inspection function and a method for inspecting the same, which have at least the following advantages:

[0047] 1. The present invention uses temperature, volume and pressure testing methods to obtain the concentration of the urea solution, and a calibrator is provided after the detector for concentration calibration, thereby eliminating the influence of temperature, bubbles and pyrolysis on the urea concentration measurement, making the detection of urea concentration more accurate;

[0048] 2. The height of each component and the structural design of the drainage section of the present invention enable the detector and the calibrator to measure only a small amount of urea solution in the container, thereby avoiding detection distortion caused by excessive detection of urea solution. At the same time, the present invention also uses a multi-point sampling method to avoid excessive sampling during the urea solution sampling process, which may result in the detection solubility being unrepresentative. Therefore, the present invention eliminates the influence of large-volume measurement of urea solution by sampling and testing urea solution at different heights, thereby further improving the detection accuracy;

[0049] 3. The present invention corrects the first urea concentration and the second urea concentration by using the third urea concentration, thereby eliminating the fluctuation of the concentration of the urea solution under different solubility states, and making the detection reliability of the urea concentration higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The present invention will be further described in detail below in conjunction with the accompanying drawings and preferred embodiments, but those skilled in the art will appreciate that these drawings are drawn only for the purpose of explaining the preferred embodiments and therefore should not be used as a limitation on the scope of the present invention. In addition, unless otherwise specified, the drawings are only schematically representing the composition or structure of the described objects and may contain exaggerated displays, and the drawings are not necessarily drawn to scale.

[0051] Figure 1 A schematic diagram of the structure of a urea filling machine with a quality inspection function provided by one embodiment of the present invention;

[0052] Figure 2A schematic flow chart of a quality inspection method for a urea filling machine provided in one embodiment of the present invention;

[0053] Figure 3 A schematic flow chart of a quality inspection method for a urea filling machine provided in another embodiment of the present invention;

[0054] 1. Filling body; 2. Detection component; 3. Urea solution; 11. Container; 12. Filling gun; 13. Drain port; 14. Insulation layer; 15. Shell; 21. Drainage section; 22. First stop valve; 23. Detector; 24. Second stop valve; 25. Calibrator; 211. Drainage tube body. DETAILED DESCRIPTION

[0055] The following is combined with Figures 1 to 3 , the present invention is described in detail.

[0056] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0057] The main idea of ​​the present invention is to obtain the concentration of the urea solution 3 by using the changes in urea volume and pressure within a specific temperature range, thereby avoiding the interference of factors such as temperature and bubbles on the concentration of the urea solution 3, thereby improving the accuracy of the concentration measurement of the urea solution 3.

[0058] For further information, see Figure 1 FIG. 1 is a schematic diagram of the structure of a urea filling machine with a quality inspection function provided by an embodiment of the present invention.

[0059] Specifically, the urea filling machine provided by the present invention is based on a filling body 1, and includes a container 11 surrounded by a shell 15, the container 11 is used to load the configured urea solution 3, and a heat preservation layer 14 is arranged around the container 11, and the heat preservation layer 14 is used to maintain the temperature of the urea solution 3 in the container 11. In addition, the shell 15 is also provided with a filling gun 12 for filling urea into the vehicle, and a drain port 13 for discharging the urea solution 3 in the container 11.

[0060] The detection component 2 is placed in the container 11, and is used to detect and output the concentration of the urea solution 3 in the container 11. The detection component 2 includes a drainage section 21, a first stop valve 22, a detector 23, a second stop valve 24 and a calibrator 25 connected in sequence. The first stop valve 22 and the second stop valve 24 are used to control the opening and closing of the valves to control the flow and temporary storage of the urea solution 3. The detector 23 includes a heating element, a thermistor and a pressure test element, which are used to realize the temperature control function and the volume measurement function; the calibrator 25 includes a straight pipe section, and a friction element and a flow rate test element are arranged in the straight pipe section to realize the friction measurement function.

[0061] The working principle of the present invention is that when the concentration of the urea solution 3 in the filling machine needs to be detected, the first stop valve 22 is opened by the controller (the second stop valve 24 is closed), and the urea solution 3 at multiple points in the container 11 is collected through the drainage section 21 and temporarily stored in the detector 23; then the first stop valve 22 is closed, so that the urea solution 3 for detection is temporarily stored in the detector 23, and then the heating element and the thermistor of the detector 23 are enabled to heat the urea solution 3 to the first preset temperature, and obtain the volume of the urea solution 3 at the temperature, so as to calculate the first urea solubility, and continue to heat to the second preset temperature to obtain the second urea concentration. Then open the second stop valve 24, so that the urea solution 3 enters the calibrator 25, and obtains the flow rate and pipe wall friction of the urea solution 3 through the friction element and the flow rate test element, so as to calculate the third urea concentration. Finally, the controller calculates the first urea concentration, the second urea concentration and the third urea concentration uploaded by the detector 23 and the calibrator 25 to obtain the urea output concentration.

[0062] Optionally, the drainage section 21 includes a plurality of drainage tubes 211 , so that the urea solution 3 can be obtained from multiple heights in the container 11 , thereby preventing the urea solution 3 from being obtained too concentratedly, resulting in a concentration test deviation of the urea solution 3 .

[0063] Optionally, the detection assembly 2 is at least partially integrated into the container 11 .

[0064] Optionally, the detection component 2 may be an independent component installed in the container 11 , or may be an integrated component integrated in the shell 15 of the container 11 , and only requires its open mouth to be placed in the urea solution 3 .

[0065] Optionally, the heating element is at least one of a heating wire, a heating block, and a heating rod.

[0066] Optionally, the detector 23 includes a cylindrical or square accommodating cavity.

[0067] Optionally, the calibrator 25 includes a straight pipe section with known diameter and length.

[0068] For further information, see Figure 2 The figure is a schematic flow chart of a quality inspection method for a urea filling machine provided in one embodiment of the present invention.

[0069] Specifically, the present invention firstly obtains the urea solution 3 through the drainage section through step S10, and temporarily stores the urea solution 3 in the detector 23, and then heats the urea solution 3 to a first preset temperature through step S20, obtains a first pressure value and a first volume value, and calculates a first urea concentration based on the first pressure value and the first volume value; since the bottom area of ​​the detector 23 is known, the first urea concentration can be calculated by a formula; then, the temperature is raised to a second preset temperature through step S30, and the second pressure value and the second volume value are obtained synchronously, and the second urea concentration is calculated based on the second pressure value and the second volume value; finally, the urea output concentration is obtained according to the first urea concentration and the second urea concentration through step S40.

[0070] Without considering the third urea concentration, the urea output concentration is obtained only by the first urea concentration and the second urea concentration. When the first urea solubility is greater than the second urea concentration, the first urea concentration is used as the urea output concentration; otherwise, the second urea concentration is used as the urea output concentration.

[0071] It is worth explaining that the concentration of the urea solution 3 is related to the solubility of urea in the solution. If it has been completely dissolved, a small amount of thermal decomposition will be generated during the heating process of the urea solution 3. At this time, the second urea concentration detected will be lower than the first urea concentration, that is, the first urea concentration is used as the urea output concentration; if the urea has not been completely dissolved, the urea solution 3 will continue to dissolve during the heating process. At this time, the second urea concentration detected will be higher than the first urea concentration, that is, the second urea concentration is used as the urea output concentration. In this way, the urea measurement concentration fluctuation problem caused by the dissolution problem of urea can be eliminated, thereby making the detection result more accurate.

[0072] For further information, see Figure 3 FIG. 1 is a flow chart of a quality inspection method for a urea filling machine provided by another embodiment of the present invention.

[0073] Specifically, after step S30, through step S31, the urea solution 3 is drained to the straight pipe section at a preset flow rate, the pipe wall friction of the straight pipe section is simultaneously obtained, and the third urea concentration is calculated based on the pipe wall friction; then through step 32, the third urea concentration is used for the calculation of the urea output concentration described in step S40.

[0074] At this time, the urea crystallization status can be judged according to the relationship among the first urea concentration, the second urea concentration and the third urea concentration, so that the detection component 2 is cleaned periodically to ensure that the detection of the concentration of the urea solution 3 is not interfered by the precipitation of urea crystals.

[0075] S41, determining whether the third urea concentration is less than or equal to the second urea concentration, if so, taking the first urea concentration as the urea output concentration; if not, executing step S42;

[0076] S42, determining whether there is urea crystal interference in the detector or the straight pipe section;

[0077] When the second urea concentration is equal to the first urea concentration:

[0078] S43, judging whether the third urea concentration is equal to the second urea concentration, if so, taking the third urea concentration as the urea output concentration; if not, executing step S44;

[0079] S44, taking the second urea concentration as the urea output concentration, and determining whether the third urea concentration is greater than the second urea concentration, if so, proceeding to step S45;

[0080] S45, determining whether there is urea crystallization interference in the straight pipe section;

[0081] When the second urea concentration is greater than the first urea concentration:

[0082] S46, determining whether the third urea concentration is greater than or equal to the second urea concentration, if so, taking the third urea concentration as the urea output concentration; if not, executing step S47;

[0083] S47. Using the second urea concentration as the urea output concentration.

[0084] Specifically, another main concept of the present invention is to correct the first urea concentration and the second urea concentration by a third urea concentration, so as to avoid the interference of solubility on the urea measurement accuracy.

[0085] It is worth explaining that, since urea crystal precipitation will affect the detection accuracy of the detector 23 and the calibrator 25, if the crystal precipitates to the detector 23, the pressure test element of the detector 23 will be disturbed, so that the pressure detection is distorted, and then the concentration detection of the urea solution 3 is distorted, which leads to the imbalance of the relationship between the first urea solution 3, the second urea concentration and the third urea solution 3, so that the crystal abnormality of the detector 23 can be judged according to the imbalanced relationship. Similarly, if there is crystal precipitation in the straight pipe section, it will cause its pipe wall to be attached, thereby causing the friction element test distortion, and will also cause the relationship between the first urea solution 3, the second urea concentration and the third urea solution 3 to be imbalanced, so that the crystal abnormality of the calibrator 25 can be judged according to the imbalanced relationship. Through the above steps, while making the urea output concentration more accurate, the crystal abnormality of the detector 23 and the calibrator 25 will also be judged, so as to realize the self-check of the detection component 2 and ensure that the detection component 2 is continuously in a high-precision state.

[0086] The present invention is described in detail above. The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the present invention and its core ideas. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A urea filling machine with quality inspection function, characterized in that: include: A filling body (1) comprising a container (11); A detection component (2) disposed in the container (11); The detection assembly (2) comprises a drainage section (21), a first stop valve (22), a detector (23), a second stop valve (24) and a calibrator (25) which are connected in sequence, and a controller (26) for controlling the first stop valve (22), the detector (23), the second stop valve (24) and the calibrator (25); The detector (23) has a temperature control function and a volume measurement function. The detector (23) comprises a straight pipe section. The straight pipe section has a friction force measurement function.

2. The urea filling machine with quality inspection function as claimed in claim 1, characterized in that: In terms of setting height, from high to low, the drainage section (21), the detector (23) and the calibrator (25) are arranged in order.

3. The urea filling machine with quality inspection function as claimed in claim 2, characterized in that: The drainage section (21) comprises a plurality of drainage tube bodies (211), and the open openings of the drainage tube bodies (211) are respectively arranged at different heights in the container (11).

4. The urea filling machine with quality inspection function as claimed in claim 1, characterized in that: The detector (23) comprises a cylindrical or square accommodating cavity.

5. The urea filling machine with quality inspection function as claimed in claim 4, characterized in that: The detector (23) comprises a heating element, a thermal element and a pressure testing element which are arranged in the accommodating cavity.

6. The urea filling machine with quality inspection function as claimed in claim 2, characterized in that: The straight pipe section includes a friction element and a flow rate testing element.

7. The urea filling machine with quality inspection function as claimed in claim 1, characterized in that: The detection component (2) is at least partially integrated into the container (11).

8. A quality inspection method for a urea filling machine, used for a urea filling machine with a quality inspection function as claimed in any one of claims 1 to 7, characterized in that: The following steps are involved: S10, the detector (23) obtains urea solution through the drainage section (21); S20, heating the urea solution to a first preset temperature, obtaining a first pressure value and a first volume value, and calculating a first urea concentration based on the first pressure value and the first volume value; S30, raising the temperature to a second preset temperature, synchronously acquiring a second pressure value and a second volume value, and calculating a second urea concentration based on the second pressure value and the second volume value; S40. Obtaining a urea output concentration according to the first urea concentration and the second urea concentration.

9. A quality inspection method for a urea filling machine as claimed in claim 8, characterized in that: After step S30, the following steps are included: S31, directing the urea solution to the straight pipe section at a preset flow rate, synchronously acquiring the pipe wall friction of the straight pipe section, and calculating a third urea concentration based on the pipe wall friction; S32: Using the third urea concentration to calculate the urea output concentration in step S40.

10. A quality inspection method for a urea filling machine as claimed in claim 9, characterized in that: In step S40, the urea output concentration is processed according to the comparison relationship among the first urea concentration, the second urea concentration and the third urea concentration: When the second urea concentration is less than the first urea concentration: S41, determining whether the third urea concentration is less than or equal to the second urea concentration, if so, taking the first urea concentration as the urea output concentration; if not, executing step S42; S42, determining whether there is urea crystal interference in the detector or the straight pipe section; When the second urea concentration is equal to the first urea concentration: S43, judging whether the third urea concentration is equal to the second urea concentration, if so, taking the third urea concentration as the urea output concentration; if not, executing step S44; S44, taking the second urea concentration as the urea output concentration, and determining whether the third urea concentration is greater than the second urea concentration, if so, proceeding to step S45; S45, determining whether there is urea crystallization interference in the straight pipe section; When the second urea concentration is greater than the first urea concentration: S46, determining whether the third urea concentration is greater than or equal to the second urea concentration, if so, taking the third urea concentration as the urea output concentration; if not, executing step S47; S47. Using the second urea concentration as the urea output concentration.

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