CN113820068B - Dynamic calibration device of soil pressure gauge - Google Patents
Dynamic calibration device of soil pressure gauge Download PDFInfo
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- CN113820068B CN113820068B CN202111075932.9A CN202111075932A CN113820068B CN 113820068 B CN113820068 B CN 113820068B CN 202111075932 A CN202111075932 A CN 202111075932A CN 113820068 B CN113820068 B CN 113820068B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L27/00—Testing or calibrating of apparatus for measuring fluid pressure
- G01L27/002—Calibrating, i.e. establishing true relation between transducer output value and value to be measured, zeroing, linearising or span error determination
- G01L27/005—Apparatus for calibrating pressure sensors
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Abstract
The invention relates to a dynamic calibration device of a soil pressure gauge, which comprises a device cylinder body, wherein a loading piston and an installation piston are hermetically sealed in the device cylinder body, a pressure gauge installation structure is arranged on the installation piston, a first liquid chamber is formed between the loading piston and the installation piston, a second liquid chamber is formed between the bottom of the device cylinder body and the installation piston, a return oil tank connected with the second liquid chamber is further arranged between the second liquid chamber and the return oil tank, a flow regulating valve is arranged between the second liquid chamber and the return oil tank, a piston driving mechanism for driving the loading piston to move at a uniform speed is further arranged on the device cylinder body, a first pressure transmitter is connected on the first liquid chamber, a waterproof adapter is arranged on the wall of the cylinder body of the device cylinder body, the inner side of the waterproof adapter is a connecting end connected with a cable of the pressure gauge, and the installation piston is in sealing fit with the inner cavity wall of the device cylinder body through a first sealing ring. The invention provides a dynamic calibration device of a soil pressure gauge, which can uniformly bear force on a sensing plate.
Description
Technical Field
The invention relates to a dynamic calibration device for calibrating a soil pressure gauge in the verification field.
Background
The soil pressure gauge is also called as soil pressure box, which is composed of back plate, induction plate, signal transmission cable, vibrating wire and exciting electromagnetic coil, etc. and is an effective monitoring device for knowing the change of soil pressure in the structure to be measured and synchronously measuring the temperature of buried point.
The soil pressure gauge is used as a monitoring sensor, the soil pressure gauge needs to be calibrated regularly according to corresponding standard requirements, the traditional soil pressure gauge calibrating device directly applies force to a sensing plate of the soil pressure gauge through a hydraulic cylinder, and a force measuring sensor is arranged between the hydraulic cylinder and the sensing plate. The output loading force of the hydraulic cylinder is used for simulating the soil layer pressure in the use environment, and the calibration of the soil pressure gauge is realized by comparing the reading of the force transducer with the reading of the soil pressure gauge. The existing calibration device for the soil pressure gauge has the following problems: the loading force output by the hydraulic cylinder is rigid loading force, and the sensing plate is easy to suffer from uneven stress so as to influence the calibration quality.
Disclosure of Invention
The invention aims to provide a dynamic calibration device of a soil pressure gauge, which can uniformly stress an induction plate.
In order to solve the technical problems, the technical scheme of the invention is as follows:
A dynamic calibration device of an earth pressure gauge is characterized in that: the dynamic calibration device comprises a device cylinder body, a loading piston and an installation piston are hermetically sealed in the device cylinder body, a pressure gauge installation structure is arranged on the installation piston, a first liquid chamber is formed between the loading piston and the installation piston, a second liquid chamber is formed between the bottom of the device cylinder body and the installation piston, a fuel return tank connected with the second liquid chamber is further arranged between the second liquid chamber and the fuel return tank, a flow regulating valve is arranged between the second liquid chamber and the fuel return tank, a piston driving mechanism for driving the loading piston to move at a constant speed is further arranged on the device cylinder body, a first pressure transmitter is connected on the first liquid chamber, a waterproof adapter is arranged on the wall of the cylinder body of the device cylinder body, the inner side of the waterproof adapter is a connecting end connected with a cable of the pressure gauge, and the installation piston is in sealing fit with the inner cavity wall of the device cylinder body through a first sealing ring.
The pressure gauge mounting structure comprises a mounting groove which is matched with the bottom of the soil pressure gauge, and a second sealing ring is arranged between the soil pressure gauge and the groove wall of the mounting groove.
The cylinder body wall of the device cylinder body comprises a fixed part and a movable part which is matched with the fixed part in a sealing guiding moving way along the up-down direction, the waterproof adapter is arranged on the movable part, a stop protrusion positioned on the inner side of the device cylinder body is fixed on the movable part, and one side of the stop protrusion, which faces the loading piston, is used for being matched with the loading piston in a stop way so that the loading piston can move downwards synchronously with the movable part in the downward moving process of the loading piston.
The mounting piston is provided with a speed sensor for detecting the moving acceleration of the mounting piston.
A second pressure transmitter is connected to the second liquid chamber.
The device cylinder body comprises a lower cylinder body part and an upper cylinder body part hinged with the lower cylinder body part, a piston driving mechanism is arranged on the upper cylinder body part, a loading piston can move between inner cavities of the upper cylinder body part and the lower cylinder body part, a first liquid chamber and a second liquid chamber are respectively formed by corresponding parts of the inner cavities of the lower cylinder body part, an oil filling port is arranged at the upper end of the first liquid chamber, the oil filling port is connected with an oil return box through a pipeline, and an oil filling pump is arranged on the pipeline.
The upper end of the first hydraulic chamber is provided with a vacuumizing port.
The upper end of the inner cavity of the lower cylinder body part is provided with a conical guide opening with a big upper part and a small lower part.
The beneficial effects of the invention are as follows: when calibrating the soil pressure gauge, install the soil pressure gauge that will treat the calibration on the installation piston, the cable conductor of soil pressure gauge links to each other with the waterproof adapter on the cylinder body wall of device cylinder body, thereby realize supplying power to the soil pressure gauge and draw forth the pressure signal of soil pressure gauge, pour into hydraulic oil into in first liquid cavity and the second liquid cavity, the loading piston is at the installation piston uniform velocity removal under the drive of piston actuating mechanism, because the liquid has incompressibility, therefore the loading piston can drive the installation piston through the hydraulic oil in the first liquid cavity and move at the uniform velocity downwards, the hydraulic oil in the second liquid cavity flows back to the backward flow case through the flow control valve. The soil pressure gauge and the mounting piston are used as a whole, the soil pressure gauge and the mounting piston are subjected to hydraulic pressure of the first hydraulic chamber, self gravity, hydraulic pressure of the second hydraulic chamber and sliding friction force between the hydraulic pressure of the second hydraulic chamber and the inner wall of the cylinder body of the device, the mounting piston moving at a constant speed is in dynamic balance, the stress of the mounting piston is stable, the soil pressure gauge is subjected to hydraulic pressure, the sensing plate of the soil pressure gauge can uniformly bear the stress, the hydraulic pressure of the first hydraulic chamber is measured through the first pressure transmitter, and the real stress of the soil pressure gauge can be calculated according to the stress area of the soil pressure gauge, so that the soil pressure gauge is calibrated. The flow rate between the second liquid chamber and the oil return box is regulated through the flow regulating valve, so that the liquid pressure of the first hydraulic chamber and the liquid pressure of the second hydraulic chamber can be changed, and the soil pressure gauge is calibrated in multiple points.
Drawings
FIG. 1 is a schematic diagram of the structure of one embodiment of the present invention;
fig. 2 is a schematic view of the upper cylinder of fig. 1 after being partially opened;
Fig. 3 is an enlarged view at a in fig. 1;
FIG. 4 is a schematic view showing the cooperation of the movable part, the fixed part and the waterproof adapter in the present invention;
in the figure, 1, a connecting end; 2. a stop protrusion; 3. cable of earth pressure meter; 4. a soil pressure gauge; 5. a second seal ring; 6. a mounting groove; 7. installing a piston; 8. an upper cylinder part; 9. loading a piston; 10. a pipeline; 11. an oil injection pump; 12. a waterproof joint; 13. a movable portion; 14. a second pressure transmitter; 15. a first seal ring; 16. a speed sensor; 17. a first pressure transmitter; 18. a lower cylinder portion; 19. a piston rod; 20. a loading cylinder; 21. a vacuum pumping port; 22. a tapered guide port; 23. a first liquid chamber; 24. a second liquid chamber; 25. a guide groove; 26. a notch; 27. and (5) returning the oil tank.
Detailed Description
In order that the invention may be readily understood, a more particular description thereof will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
An embodiment of a dynamic calibration device for an earth pressure gauge in the present invention is shown in fig. 1 to 4:
The device comprises a device cylinder body, wherein the device cylinder body comprises a lower cylinder body part 18 and an upper cylinder body part 8 which is hinged with the lower cylinder body part 18, a mounting piston 7 is assembled in the inner cavity of the lower cylinder body part 18 in a sealing guiding and moving way, and a first sealing ring 15 is arranged between the mounting piston 7 and the inner cavity wall of the lower cylinder body part. The upper cylinder part is provided with a piston driving mechanism, the piston driving mechanism in the embodiment is a loading cylinder 20, a piston rod 19 of the loading cylinder is connected with a loading piston 9, the loading piston 9 can move between inner cavities of the upper cylinder part and the lower cylinder part, the loading piston 9 is in sealing guide fit with the inner cavity of the lower cylinder part, and the loading piston is used for driving the mounting piston to move at a constant speed.
The pressure gauge mounting structure is arranged on the mounting piston and comprises a mounting groove 6 which is matched with the bottom of the soil pressure gauge, and a second sealing ring 5 is arranged between the soil pressure gauge and the groove wall of the mounting groove.
When the loading piston is in sealing sliding fit with the inner cavity of the lower cylinder part, a first liquid chamber 23 is formed between the loading piston and the mounting piston, a second liquid chamber 24 is formed between the bottom of the device cylinder and the mounting piston, the dynamic calibration device further comprises an oil return tank 27 connected with the second liquid chamber, and a flow regulating valve (not shown in the figure) is arranged between the second liquid chamber 24 and the oil return tank. The upper end of the first liquid chamber is provided with an oil filling port, the oil filling port is connected with an oil return box through a pipeline 10, the pipeline is provided with an oil filling pump 11, and the upper end of the first liquid chamber is provided with a vacuumizing port 12.
The first liquid chamber is connected to a first pressure transmitter 17 and the second liquid chamber is connected to a second pressure transmitter 14. The upper end of the inner cavity of the lower cylinder part is provided with a conical guide opening 22 with a large upper part and a small lower part, and the conical guide opening can guide the loading piston to smoothly enter the inner cavity of the lower cylinder part. The cylinder wall of the lower cylinder part 18 comprises a fixed part and a movable part 13 which is matched with the fixed part in a sealing guiding and moving way along the up-down direction, specifically, a guiding groove 26 which extends along the up-down direction is arranged in the fixed part, the movable part is of a plate-shaped structure which is matched with the guiding groove in a sealing and sliding way, a waterproof adapter 12 is fixed on the movable part, the inner side of the waterproof adapter is a connecting end 1 which is used for being connected with a cable 3 of a pressure gauge, the waterproof adapter 12 in the embodiment is a waterproof adapter, the inner side and the outer side of the guiding groove are provided with notches 26, the size of the notch is smaller than that of the movable part 13, and the waterproof adapter can move up and down in the notch.
The movable part is fixedly provided with a stop bulge 2 positioned at the inner side of the device cylinder body, the stop bulge 2 penetrates through the notch at the inner side, and one side of the stop bulge facing the loading piston is used for being in stop fit with the loading piston so that the loading piston moves downwards synchronously with the movable part in the downward movement process of the loading piston.
When the hydraulic cylinder is used, firstly, as shown in fig. 2, the upper cylinder body part is turned upwards, the soil pressure gauge to be calibrated is installed in the installation groove of the installation piston, a cable of the soil pressure gauge is connected with the connecting end on the inner side of the waterproof joint, power can be supplied to the soil pressure gauge from the outside and detection signals of the soil pressure gauge are led out, then the upper cylinder body part is turned downwards, as shown in fig. 1, then, a piston rod of the loading cylinder drives the loading piston to enter the inner cavity of the lower cylinder body part, at the moment, the loading piston is in sealing guide fit with the inner cavity wall of the lower cylinder body part, a first hydraulic cavity is formed between the loading piston and the installation piston, the first hydraulic cavity is vacuumized through the vacuumizing opening, hydraulic oil is injected into the first hydraulic cavity through the oil injection pump, no bubbles can be ensured in the first hydraulic cavity after vacuumizing, hydraulic oil can be filled in the first hydraulic cavity, and hydraulic oil can be always injected in the second hydraulic cavity.
Then, the loading cylinder drives the loading piston to move downwards at a uniform speed, because the liquid is incompressible, the soil pressure gauge and the loading piston also move downwards at a uniform speed together, hydraulic oil in the second hydraulic chamber flows back to the oil return box through the flow regulating valve, interference is caused to movement of the loading piston by a cable of the soil pressure gauge so as to avoid interference to movement of the loading piston due to overlarge movement distance of the soil pressure gauge, the cable causes dragging to the soil pressure gauge, after the loading piston moves for a certain distance, the bottom of the loading piston is propped against the stop protrusion, and the loading piston moves downwards synchronously together with the stop protrusion, the movable part and the waterproof adapter, so that influence of the cable to a dynamic calibration process can be effectively avoided.
The speed sensor can judge whether the installation piston moves at a constant speed, in the dynamic balance of the constant speed movement of the installation piston, the upper side of the soil pressure gauge is uniformly pressed by the first hydraulic chamber, the pressure intensity of the first hydraulic chamber is measured through the first pressure transmitter, then the real stress of the soil pressure gauge is calculated according to the stress area of the soil pressure gauge, so that the soil pressure gauge is calibrated, and of course, the soil pressure gauge for directly measuring the pressure intensity can be calibrated according to the first pressure transmitter. The soil pressure gauge and the mounting piston are used as a whole, and the soil pressure gauge and the mounting piston are subjected to hydraulic pressure of the first hydraulic chamber, self gravity, hydraulic pressure of the second hydraulic chamber and sliding friction force between the second hydraulic chamber and the inner wall of the cylinder body of the device, so that the sealing performance requirement on the first sealing ring is small, and the use requirement can be met by using a common O-shaped sealing ring for the first sealing ring. The pressure of the first hydraulic chamber and the pressure of the second hydraulic chamber can be changed by adjusting the size of the flow regulating valve, so that the multi-point calibration of the soil pressure gauge is realized.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims (7)
1. A dynamic calibration device of an earth pressure gauge is characterized in that: the device comprises a device cylinder body, a loading piston and an installation piston are hermetically sealed in a guiding mode in the device cylinder body, a pressure gauge installation structure is arranged on the installation piston, a first liquid chamber is formed between the loading piston and the installation piston, a second liquid chamber is formed between the bottom of the device cylinder body and the installation piston, the dynamic calibration device further comprises an oil return tank connected with the second liquid chamber, a flow regulating valve is arranged between the second liquid chamber and the oil return tank, a piston driving mechanism for driving the loading piston to move at a uniform speed is further arranged on the device cylinder body, a first pressure transmitter is connected to the first liquid chamber, a waterproof adapter is arranged on the cylinder body wall of the device cylinder body, the inner side of the waterproof adapter is a connecting end connected with a cable of the pressure gauge, the installation piston is in sealing fit with the inner cavity wall of the device cylinder body through a first sealing ring, the cylinder body wall of the device cylinder body comprises a fixed part and a movable part in sealing guiding movement fit along the up-down direction, a stop bulge located on the movable part is fixed on the movable part, one side of the stop bulge facing the loading piston is used for being matched with the loading piston in the downward movement of the loading piston at a uniform speed, the loading piston is also moved at the uniform speed along with the backward flow of the loading piston, and the hydraulic oil can not move at the uniform speed through the sealing piston.
2. The dynamic calibration device according to claim 1, wherein: the pressure gauge mounting structure comprises a mounting groove which is matched with the bottom of the soil pressure gauge, and a second sealing ring is arranged between the soil pressure gauge and the groove wall of the mounting groove.
3. The dynamic calibration device according to claim 1, wherein: the mounting piston is provided with a speed sensor for detecting the moving acceleration of the mounting piston.
4. The dynamic calibration device according to claim 1, wherein: a second pressure transmitter is connected to the second liquid chamber.
5. The dynamic calibration device according to any one of claims 1 to 4, wherein: the device cylinder body comprises a lower cylinder body part and an upper cylinder body part hinged with the lower cylinder body part, a piston driving mechanism is arranged on the upper cylinder body part, a loading piston can move between inner cavities of the upper cylinder body part and the lower cylinder body part, a first liquid chamber and a second liquid chamber are respectively formed by corresponding parts of the inner cavities of the lower cylinder body part, an oil filling port is arranged at the upper end of the first liquid chamber, the oil filling port is connected with an oil return box through a pipeline, and an oil filling pump is arranged on the pipeline.
6. The dynamic calibration device of claim 5, wherein: the upper end of the first hydraulic chamber is provided with a vacuumizing port.
7. The dynamic calibration device of claim 5, wherein: the upper end of the inner cavity of the lower cylinder body part is provided with a conical guide opening with a big upper part and a small lower part.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111075932.9A CN113820068B (en) | 2021-09-14 | 2021-09-14 | Dynamic calibration device of soil pressure gauge |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111075932.9A CN113820068B (en) | 2021-09-14 | 2021-09-14 | Dynamic calibration device of soil pressure gauge |
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| CN113820068A CN113820068A (en) | 2021-12-21 |
| CN113820068B true CN113820068B (en) | 2024-07-19 |
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| CN211178852U (en) * | 2020-01-07 | 2020-08-04 | 刘丹丹 | Verification and calibration device for pore water pressure gauge |
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| CN103712740B (en) * | 2014-01-09 | 2016-05-18 | 中国人民解放军总参谋部工程兵科研三所 | Flat pressure sensor dynamic high-pressure calibrating installation |
| CN105424273A (en) * | 2015-12-15 | 2016-03-23 | 河南工业大学 | Novel indoor earth pressure cell calibration tank |
| US10775257B2 (en) * | 2016-09-23 | 2020-09-15 | Spektra Schwingungstechnik Und Akustik Gmbh Dresden | Device and method for dynamically calibrating pressure sensors |
| CN107328522B (en) * | 2017-08-09 | 2019-06-25 | 武汉科技大学 | A kind of soil pressure cell caliberating device and its application method |
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| CN212432417U (en) * | 2020-05-28 | 2021-01-29 | 中国石油天然气股份有限公司 | Pressure gauge calibrating device |
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| CN206974611U (en) * | 2017-07-13 | 2018-02-06 | 上海港湾工程质量检测有限公司 | The positive and negative two-way caliberating device of pressure sensor |
| CN211178852U (en) * | 2020-01-07 | 2020-08-04 | 刘丹丹 | Verification and calibration device for pore water pressure gauge |
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