On-line calibration device for open channel weir groove flowmeter

Abstract

The utility model discloses an open channel weir groove flowmeter on-line calibration device which comprises a frame body, a top plate, a lifting plate and a bottom plate which are sequentially arranged in parallel from top to bottom, the top plate and the bottom plate are fixed through guide columns, and the lifting plate and the guide columns are movably assembled and have the straight reciprocating freedom degree along the guide columns. The height gauge movably penetrates through the lifting plate, and the two ends of the height gauge are detachably assembled with the top plate and the bottom plate respectively; the laser range finder is assembled with the lifting plate and synchronously moves along with the lifting plate; the top plate is provided with the lock catch, and the lock catch is detachably provided with a liquid level probe. According to the utility model, on-site calibration of liquid level and flow parameters of the open channel flowmeter can be realized. Meanwhile, measurement data of the laser range finder and the height gauge can be mutually verified.

Description

Technical Field

[0001] The utility model relates to the field of flow calibration instruments, in particular to an online calibration device for an open channel weir flow meter. Background Art

[0002] JJG711-1990 "Trial Calibration Procedure for Open Channel Weir Flowmeters" has been in use for more than 30 years and can no longer meet the needs of online calibration of many types of open channel weir flowmeters, and has great limitations. In practical applications, the water measuring weir of the open channel flowmeter is large in size and the installation position is relatively fixed, which brings certain difficulties to the on-site calibration work. At the same time, there are many factors affecting online calibration, such as temperature, uneven weir surface, uncontrollable flow rate, uneven flow state, etc. The results of uncertainty assessment cannot meet the traceability standards of open channel flowmeters, that is, the uncertainty of the measurement results is large. Therefore, it is necessary to study and develop a new online calibration device and method for open channel weir flowmeters to improve the accuracy and reliability of calibration.

[0003] The HJ15-2019 "Technical Requirements and Test Methods for Ultrasonic Open Channel Sewage" environmental protection standard was implemented on March 24, 2020. The standard details the test method for open channel sewage flow meters, which is a combination of "laboratory liquid level full-range measurement device" and "field liquid level and flow fixed-point comparison device".

[0004] "Laboratory liquid level full range measurement device" as attached Figure 1 As shown, a primary instrument 10 (liquid level probe) is placed on the upper part of the device, and the full-scale measurement error of the liquid level probe is measured by manually moving the reflector 11. A vertical height caliper 12 is also provided between the primary instrument 10 and the reflector 11.

[0005] The "on-site liquid level and flow fixed-point comparison device" uses a liquid level meter plus a standard flow calculation formula for on-site comparison. The liquid level comparison error is measured by using a standard liquid level meter and a measured flow meter liquid level probe to measure the liquid level value at the same water level observation section for on-site comparison. The flow comparison error is measured by measuring the instantaneous flow at the same water level observation section of the two for on-site comparison. The standard flow is calculated by adding the liquid level value to the standard flow calculation formula.

[0006] At present, there are problems with this method: first, the liquid level detection needs to be completed in the laboratory and cannot be completed on-site together with the flow comparison; second, the height gauge reading of the liquid level detection is inconvenient and the detection efficiency is low; third, the liquid level probe of the liquid level detection device is not firmly fixed and the measurement accuracy is not high. Utility Model Content

[0007] The problem to be solved by the utility model is to provide an online calibration device for an open channel weir flowmeter, which can realize on-site calibration of the liquid level and flow parameters of the open channel flowmeter. At the same time, the measurement data of the laser rangefinder and the height gauge can be mutually verified.

[0008] In order to solve the above problems, the utility model provides an online calibration device for an open channel weir flowmeter. To achieve the above purpose, the technical solution adopted by the utility model to solve the technical problem is:

[0009] The online calibration device of an open channel weir flowmeter comprises: a frame, comprising a top plate, a lifting plate, and a bottom plate which are arranged in parallel from top to bottom, the top plate and the bottom plate being fixed by guide pillars, the lifting plate and the guide pillars being movably assembled and having linear reciprocating freedom along the guide pillars; a height gauge, movably penetrating the lifting plate, the two ends of the height gauge being detachably assembled with the top plate and the bottom plate respectively; a laser rangefinder, assembled with the lifting plate and moving synchronously with the lifting plate; a lock buckle, the top plate is provided with a lock buckle, and the lock buckle is detachably assembled with a liquid level probe.

[0010] The beneficial effects of adopting the above technical solution are: first, the calibration device of this technical solution is designed to be small and compact as a whole, easy to carry, and can realize on-site calibration of the liquid level and flow parameters of the open channel flowmeter. Secondly, the device is equipped with a laser rangefinder on the basis of a height gauge to improve the efficiency of measurement. With the rise and fall of the lifting plate and the scale of the height gauge, the measurement data of the laser rangefinder and the height gauge can be verified with each other. Thirdly, the upper end lock can firmly fix the liquid level probe, and is suitable for probes of different specifications and models, and has a wide range of applicability. Finally, the height gauge can be flexibly disassembled to calibrate the real-time liquid level and flow of the open channel flowmeter. Improve the accuracy and reliability of the flowmeter calibration and ensure the accuracy of the measurement results.

[0011] As a further improvement of the utility model, the orientation of the laser rangefinder and the orientation of the liquid level probe are parallel to the length direction of the guide column itself; the laser rangefinder is fixed to the lower surface of the lifting plate.

[0012] The beneficial effect of adopting the above technical solution is that the whole is vertical and the detection is accurate.

[0013] As a further improvement of the present invention, the direction of the liquid level probe intersects with the lifting plate; the movement path of the laser rangefinder does not intersect with the bottom plate, and the bottom plate has a gap for avoiding the laser rangefinder.

[0014] The beneficial effect of adopting the above technical solution is that the lifting range of the lifting plate is larger and is not affected by the laser rangefinder.

[0015] As a further improvement of the present invention, the lock includes a circular ring member arranged above the top plate, the circular ring member and the top plate are fixed by a column, the lock also includes a plurality of C-shaped members arranged on the inner ring of the circular ring member, the C-shaped member is fixed with an adjusting bolt that passes through the circular ring member, one end of the adjusting bolt protrudes from the outer ring of the circular ring member, and the C-shaped member has the degree of translational freedom to move radially along the circular ring member as the adjusting bolt rotates.

[0016] The beneficial effect of adopting the above technical solution is that such a design facilitates manual adjustment by personnel to realize loading and unloading of the liquid level probe, and can also clamp liquid level probes of different sizes, with a better overall clamping effect.

[0017] As a further improvement of the utility model, the top plate is provided with a lower hole, and the upper hole is surrounded by all C-shaped parts. The liquid level probe is clamped at the concave surface of the C-shaped part itself, and the lower hole is for the liquid level probe to pass through.

[0018] The beneficial effect of adopting the above technical solution is that it can be used for a liquid level probe with a longer axial length.

[0019] As a further improvement of the utility model, the lifting plate is movably assembled through the guide sleeve and the guide pillars, the number of the guide pillars is four, and the lines connecting the centroids of the four guide pillars in sequence form a rectangle.

[0020] The beneficial effect of adopting the above technical solution is that the overall shape is symmetrical, so that the lifting plate serving as a reflector can also move smoothly when it is lifted or lowered.

[0021] As a further improvement of the present invention, the scale range of the height gauge is 0 mm to 1000 mm.

[0022] As a further improvement of the present invention, both ends of the height gauge are snap-connected with the top plate and the bottom plate; the cross-sectional profile of the height gauge is rectangular, and the profile of the hole in the lifting plate for the height gauge to pass through is a proportional enlargement of the cross-sectional profile of the height gauge.

[0023] The beneficial effects of adopting the above technical solution are: it is convenient for the quick disassembly and assembly of the height gauge, and it is also convenient for the lifting plate to pass smoothly relative to the height gauge. At the same time, once the height gauge is deformed or skewed, it is easy to be squeezed with the hole, which is also easy for personnel to detect. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1It is a stereogram of an implementation method in the prior art;

[0026] Figure 2 It is one of the three-dimensional diagrams of an embodiment of the utility model;

[0027] Figure 3 This is the second stereogram of an implementation manner of the utility model.

[0028] 1-guide column; 2-height gauge; 3-top plate; 301-lower hole; 4-lifting plate; 5-bottom plate; 501-notch; 6-guide sleeve; 7-laser rangefinder; 8-locking buckle; 801-circular ring; 802-adjusting bolt; 803-C-shaped piece; 804-upper hole; 805-column; 10-primary instrument; 11-reflection plate; 12-height caliper. DETAILED DESCRIPTION

[0029] The following is a further detailed description of the present invention in conjunction with specific embodiments:

[0030] In order to achieve the purpose of the utility model, an open channel weir flowmeter online calibration device comprises: a frame, comprising a top plate 3, a lifting plate 4, and a bottom plate 5 arranged in parallel from top to bottom, the top plate 3 and the bottom plate 5 are fixed by a guide column 1, the lifting plate 4 is movably assembled with the guide column 1 and has a linear reciprocating freedom along the guide column 1; a height gauge 2, which movably passes through the lifting plate 4, and the two ends of the height gauge 2 are detachably assembled with the top plate 3 and the bottom plate 5 respectively; a laser rangefinder 7, which is assembled with the lifting plate 4 and moves synchronously with the lifting plate 4; a lock buckle 8, the top plate 3 is provided with a lock buckle 8, and the lock buckle 8 is detachably assembled with a liquid level probe.

[0031] The beneficial effects of adopting the above technical solution are: first, the calibration device of this technical solution is designed to be small and compact as a whole, easy to carry, and can realize on-site calibration of the liquid level and flow parameters of the open channel flowmeter. Secondly, the device is equipped with a laser rangefinder on the basis of a height gauge to improve the efficiency of measurement. With the rise and fall of the lifting plate and the scale of the height gauge, the measurement data of the laser rangefinder and the height gauge can be verified with each other. Thirdly, the upper end lock can firmly fix the liquid level probe, and is suitable for probes of different specifications and models, and has a wide range of applicability. Finally, the height gauge can be flexibly disassembled to calibrate the real-time liquid level and flow of the open channel flowmeter. Improve the accuracy and reliability of the flowmeter calibration and ensure the accuracy of the measurement results.

[0032] In other embodiments of the present invention, the orientation of the laser rangefinder 7 and the orientation of the liquid level probe are parallel to the length direction of the guide column 1 itself; the laser rangefinder 7 is fixed to the lower surface of the lifting plate 4.

[0033] The beneficial effect of adopting the above technical solution is that the whole is vertical and the detection is accurate.

[0034] In other embodiments of the present invention, the direction of the liquid level probe intersects with the lifting plate 4 ; the movement path of the laser rangefinder 7 does not intersect with the bottom plate 5 , and the bottom plate 5 has a notch 501 for avoiding the laser rangefinder 7 .

[0035] The beneficial effect of adopting the above technical solution is that the lifting range of the lifting plate is larger and is not affected by the laser rangefinder.

[0036] In other embodiments of the present invention, the lock buckle 8 includes a circular ring 801 disposed above the top plate 3, the circular ring 801 and the top plate 3 are fixed by a column 805, and the lock buckle 8 also includes a plurality of C-shaped pieces 803 disposed on the inner ring of the circular ring 801, the C-shaped piece 803 is fixed with an adjustment bolt 802 that passes through the circular ring 801, one end of the adjustment bolt 802 emerges from the outer ring of the circular ring 801, and the C-shaped piece 803 has the degree of freedom of translation along the radial direction of the circular ring 801 as the adjustment bolt 802 rotates. Figure 1 As shown, for the sake of clarity, the liquid level probe is not shown in the figure.

[0037] The beneficial effect of adopting the above technical solution is that such a design facilitates manual adjustment by personnel to realize loading and unloading of the liquid level probe, and can also clamp liquid level probes of different sizes, with a better overall clamping effect.

[0038] In other embodiments of the present invention, the top plate 3 is provided with a lower hole 301 , and an upper hole 804 is surrounded by all C-shaped members 803 . The concave surface of the C-shaped member 803 clamps the liquid level probe, and the lower hole 804 is for the liquid level probe to pass through.

[0039] The beneficial effect of adopting the above technical solution is that it can be used for a liquid level probe with a longer axial length.

[0040] In other embodiments of the present invention, the lifting plate 4 is movably assembled with the guide pillars 1 through the guide sleeves 6. There are four guide pillars 1, and the lines connecting the centroids of the four guide pillars 1 in sequence form a rectangle.

[0041] The beneficial effect of adopting the above technical solution is that the overall shape is symmetrical, so that the lifting plate serving as a reflector can also move smoothly when it is lifted or lowered.

[0042] In some other embodiments of the present invention, the scale range of the height gauge 2 is 0 mm to 1000 mm, and the unit scale of the height gauge 2 is 1 mm.

[0043] In other embodiments of the present invention, both ends of the height gauge 2 are snap-connected with the top plate 3 and the bottom plate 5; the cross-sectional contour of the height gauge 2 is rectangular, and the contour of the hole in the lifting plate 4 for the height gauge 2 to pass through is a proportional enlargement of the cross-sectional contour of the height gauge 2.

[0044] The beneficial effects of adopting the above technical solution are: it is convenient for the quick disassembly and assembly of the height gauge, and it is also convenient for the lifting plate to pass smoothly relative to the height gauge. At the same time, once the height gauge is deformed or skewed, it is easy to be squeezed with the hole, which is also easy for personnel to detect.

[0045] Bring the device to the site to test a super-clear channel sewage flow meter with a liquid level range of 30mm to 330mm. The steps and data are as follows:

[0046] First, fix the primary instrument of the open channel weir flowmeter on the bracket above the height gauge 2, fix the instrument with the butterfly bolt lock 8, move the reflector to the height gauge 0mm, the reflector is the lifting plate 4, and the liquid level is zeroed. According to the requirements of HJ15-2019 "Technical Requirements and Detection Methods for Ultrasonic Open Channel Sewage", move the reflector to 20%, 50%, and 80% of the maximum scale 1000mm of the height gauge 2, and record the liquid level indication of the open channel weir flowmeter and the laser rangefinder. Perform six cycles of measurement, calculate the liquid level measurement error, and take the arithmetic mean of the six indication errors as the measurement result. The results are shown in Table 1.

[0047] Table 1 Comparison of the level indications of the open channel weir flowmeter and the laser rangefinder

[0048]

[0049] The primary instrument of the open channel weir flowmeter was installed back to the site to make the flowmeter operate normally. The standard liquid level meter was installed in the channel. The liquid level value at the same water level observation section was measured with the standard liquid level meter and the open channel weir flowmeter to be measured, and the on-site real flow comparison test was carried out. After the real-time liquid level stabilized, the data was read every 2 minutes for six consecutive times, and the liquid level comparison error was calculated respectively. The value of the six indication errors was taken as the measurement result. The results of the on-site liquid level value at this time are shown in Table 2.

[0050] Table 2 Comparison of the data collected by the standard level meter and the open channel weir flowmeter under test

[0051]

[0052] It can be seen from the above two tables that: according to the regulations, the device was used to test an open channel weir flowmeter on-site, and the level measurement errors at the three test points all met the requirements. Then a standard level gauge was used to measure the level comparison error at the measuring point 180mm, and the measurement results met the requirements.

[0053] Since the vertical dimension of this technical solution is relatively long, in order to clearly show the structure of each component, Figure 2 It is a fractured painting method. Figure 2 It is an oblique perspective from top to bottom. Figure 3 It is an oblique perspective from bottom to top.

[0054] The device is made of aluminum, compact and easy to carry. The device's height caliper has a measurement range of 0mm to 1000mm, with a maximum allowable error of no more than ±0.5mm; the maximum allowable error of the laser rangefinder is no more than ±1mm; the flatness of the reflector does not exceed 0.1mm.

[0055] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with this technology to understand the content of the utility model and implement it. They cannot be used to limit the protection scope of the utility model. All equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. An online calibration device for an open channel weir flowmeter, characterized in that: include: The frame body comprises a top plate, a lifting plate and a bottom plate which are arranged in parallel from top to bottom, the top plate and the bottom plate are fixed by guide pillars, and the lifting plate is movably assembled with the guide pillars and has a linear reciprocating freedom along the guide pillars; A height gauge is movable through the lifting plate, and the two ends of the height gauge are detachably assembled with the top plate and the bottom plate respectively; A laser rangefinder is assembled with the lifting plate and moves synchronously with the lifting plate; Lock buckle: the top plate is provided with a lock buckle, and the lock buckle is detachably equipped with a liquid level probe.

2. The online calibration device for an open channel weir flowmeter according to claim 1, characterized in that: The directions of the laser rangefinder and the liquid level probe are both parallel to the length direction of the guide column itself; the laser rangefinder is fixed to the lower surface of the lifting plate.

3. The online calibration device for an open channel weir flowmeter according to claim 2, characterized in that: The direction of the liquid level probe intersects with the lifting plate; the movement path of the laser rangefinder does not intersect with the bottom plate, and the bottom plate has a gap to avoid the laser rangefinder.

4. The online calibration device for an open channel weir flowmeter according to claim 1, characterized in that: The lock buckle includes a circular ring member arranged above the top plate, and the circular ring member and the top plate are fixed by a column. The lock buckle also includes a plurality of C-shaped members arranged on the inner ring of the circular ring member, and the C-shaped member is fixed with an adjusting bolt that passes through the circular ring member, and one end of the adjusting bolt protrudes from the outer ring of the circular ring member. The C-shaped member has the degree of translational freedom to move radially along the circular ring member as the adjusting bolt rotates.

5. The online calibration device for an open channel weir flowmeter according to claim 4, characterized in that: The top plate is provided with a lower hole, and an upper hole is surrounded by all C-shaped members. The liquid level probe is clamped at the concave surface of the C-shaped member itself, and the lower hole is for the liquid level probe to pass through.

6. The online calibration device for an open channel weir flowmeter according to claim 1, characterized in that: The lifting plate is movably assembled through guide sleeves and guide pillars. The number of the guide pillars is four, and the lines connecting the centroids of the four guide pillars in sequence form a rectangle.

7. The online calibration device for an open channel weir flowmeter according to claim 1, characterized in that: The scale range of the height gauge is from 0 mm to 1000 mm.

8. The open channel weir flowmeter online calibration device according to claim 1, characterized in that: The two ends of the height gauge are snap-connected with the top plate and the bottom plate; the cross-sectional profile of the height gauge is rectangular, and the profile of the hole in the lifting plate for the height gauge to pass through is a proportional enlargement of the cross-sectional profile of the height gauge.

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