High-precision water pressure test system and use method

Abstract

The embodiment of the invention provides a high-precision water pressure test system and a use method. The high-precision water pressure test system comprises a water supply device, a water stop device and a measuring device, the water supply device comprises a water supply pipeline and a steel floral tube arranged at a drilling test section, the water stop device comprises pressurizing equipment, a pressurizing tube, an upper water stop plug and a lower water stop plug, and the measuring device comprises a first pressure sensor, a second pressure sensor, a third pressure sensor and a data acquisition device; the two ends of the steel floral tube are connected with a lower water stop plug and an upper water stop plug respectively, the first pressure sensor is arranged on the outer side of the top of the upper water stop plug, the second pressure sensor is arranged in the steel floral tube, the third pressure sensor is arranged on the outer side of the bottom of the lower water stop plug, and all the sensors are electrically connected to the data acquisition device. Pressure data inside and outside a drill hole test section in the water pressure test process are monitored in real time, whether leakage exists at a water stop plug or not is judged, and the accuracy of water pressure flow data is guaranteed.

Description

Technical Field

[0001] The embodiments of the present disclosure belong to the field of engineering survey technology, and specifically relate to a high-precision water pressure test system and a method of using the same. Background Art

[0002] When constructing an underground water-sealed cavern in a rock mass, the water seal is the key to the underground cavern. Therefore, the water permeability of the rock mass within the site must be studied. The water pressure test is the most commonly used in-situ permeability test for rock and soil. A certain length of the drilled test section is isolated using a water-stop plug, and then water is supplied to the test section at different pressures to measure the corresponding flow rate. The water permeability of the rock mass is determined based on the water supply pressure, the length of the test section and the stable infiltration water volume, which serves as the basic basis for the water seal design of the underground cavern and the calculation of the water inflow.

[0003] However, among the technologies currently used, firstly, pressure gauges and flow meters are generally arranged at the borehole orifices. Due to the pressure loss of pipelines, pipe joints, etc., the pressure in the test section is not exactly the same as the orifice pressure, and the calculation (calibration) of the pipeline pressure loss is difficult; secondly, it is difficult to determine whether there is water leakage in the test plug and the water supply pipe joint, and there is a lack of inspection on the water-stopping effect of the plug; in addition, due to the large difference in water supply caused by different permeabilities of rocks, the range or accuracy of a single flow meter is limited, which affects the accuracy of the results. Therefore, a high-precision water pressure test system and a method for use are proposed. Summary of the invention

[0004] The embodiments of the present disclosure aim to solve at least one of the technical problems existing in the prior art and provide a high-precision water pressure testing system and a method of use.

[0005] On the one hand, an embodiment of the present disclosure provides a high-precision water pressure test system, the water pressure test system comprising a water supply device, a water stop device and a measuring device;

[0006] The water supply device includes a water supply pipeline and a steel flower pipe arranged in the drilling test section, the water stop device includes a pressurizing device, a pressurizing pipe, an upper water stop plug and a lower water stop plug, and the measuring device includes a first pressure sensor, a second pressure sensor, a third pressure sensor and a data acquisition device; wherein,

[0007] The first end of the steel flower pipe is connected to the lower water stop plug, the second end of the steel flower pipe is connected to the upper water stop plug, and the upper water stop plug is also connected to the water outlet of the water supply pipeline; the pressurizing device is connected to the upper water stop plug and the lower water stop plug in sequence through the pressurizing pipe; the first pressure sensor is arranged on the outside of the top of the upper water stop plug, the second pressure sensor is arranged inside the steel flower pipe, the third pressure sensor is arranged on the outside of the bottom of the lower water stop plug, and each of the sensors is electrically connected to the data acquisition device to monitor the pressure data inside and outside the drilling test section.

[0008] Optionally, the measuring device further comprises a plurality of electromagnetic flow components and pressure transmitters;

[0009] The input ends of the electromagnetic flow element and the pressure transmitter are sequentially arranged in series on the water supply pipeline along the water supply direction of the water supply pipeline, and the output ends of the electromagnetic flow element and the pressure transmitter are respectively connected to the data acquisition device.

[0010] Optionally, the electromagnetic flow meter includes a first electromagnetic flow meter, a second electromagnetic flow meter and a third electromagnetic flow meter;

[0011] The input ends of the first electromagnetic flowmeter, the second electromagnetic flowmeter and the third electromagnetic flowmeter are sequentially arranged in series in the water supply pipeline along the water supply direction of the water supply pipeline, and the output ends of the first electromagnetic flowmeter, the second electromagnetic flowmeter and the third electromagnetic flowmeter are respectively connected to the data acquisition device.

[0012] Optionally, the water pressure test system further comprises a first control valve, a second control valve and a third control valve which are arranged in series on the water supply pipeline;

[0013] The first control valve is located between the water inlet of the water supply pipeline and the first electromagnetic flowmeter, the second control valve is located between the first electromagnetic flowmeter and the second electromagnetic flowmeter, and the third control valve is located between the second electromagnetic flowmeter and the third electromagnetic flowmeter; and,

[0014] The water pressure test system also includes a first branch connected in parallel to the second control valve and a second branch connected in parallel to the third control valve; wherein the input end of the second electromagnetic flowmeter is located between the branch control valve of the first branch and the second control valve, and the input end of the third electromagnetic flowmeter is located between the branch control valve of the second branch and the third control valve.

[0015] Optionally, the water supply device further comprises a water reservoir and a variable frequency centrifugal pump connected in series to the water supply pipeline, and the water pressure test system further comprises a power supply;

[0016] The water reservoir is in communication with the water inlet of the water supply pipeline, and the variable frequency centrifugal pump is located between the water inlet of the water supply pipeline and the first control valve;

[0017] The power supply is used to supply power to the variable frequency centrifugal pump and the data acquisition device.

[0018] Optionally, the water pressure test system further comprises a return water pipeline arranged in series with the water supply pipeline, and a fourth control valve arranged in series with the return water pipeline;

[0019] The water inlet of the water return pipeline is located between the variable frequency centrifugal pump and the first control valve, and the water outlet of the water return pipeline is communicated with the water reservoir.

[0020] Optionally, the water supply device further comprises at least one drill rod;

[0021] The top of the drill rod is connected to the water outlet of the water supply pipeline, and the bottom of the drill rod is connected to the top of the upper water stop plug.

[0022] Optionally, the water pressure test system further comprises a protective cover arranged at the bottom of the lower water stop plug, and the third pressure sensor is connected to the bottom of the lower water stop plug via a waterproof joint and arranged in the protective cover.

[0023] Optionally, the water pressure test system further comprises a three-way sealer;

[0024] The first opening of the three-way sealer is connected to the bottom of the drill pipe, and the second opening of the three-way sealer is connected to the top of the upper water stop plug; and,

[0025] The first pressure sensor, the second pressure sensor and the third pressure sensor are all connected to the data acquisition device through cables; wherein the cables of the second pressure sensor and the third pressure sensor pass through the third opening of the three-way sealer and are connected to the data acquisition device through a waterproof connector.

[0026] On the other hand, an embodiment of the present disclosure provides a method for using a water pressure test system, wherein the water pressure test system is the high-precision water pressure test system described above, and the method for using includes:

[0027] S1: Determine the location and length of the test section and the placement of the water stop plug based on the drilling core and in-hole ultrasonic imaging results;

[0028] S2: Fix the second pressure sensor inside the steel flower pipe, and connect the drill rod to the upper end of the steel flower pipe according to the length of the test section; fix the third pressure sensor in the protective cover at the bottom of the lower water stop plug, and pass the cable through the waterproof joint at the bottom of the lower water stop plug, the lower water stop plug and the steel flower pipe; pass the cables of the second pressure sensor and the third pressure sensor through the upper water stop plug and the three-way sealer, connect the steel flower pipe and the upper water stop plug, and connect the three-way sealer to the upper water stop plug; connect the pressurizing equipment, the upper water stop plug and the lower water stop plug through the pressurizing pipe; fix the first pressure sensor on the outside of the top of the upper water stop plug; tighten the waterproof joint of the three-way sealer to make it sealed;

[0029] S3: Connect the drill pipe to the three-way sealer, and connect the top of the drill pipe to the water supply pipeline; connect a water reservoir to the other end of the water supply pipeline, and install a variable frequency centrifugal pump, a first electromagnetic flowmeter, a second electromagnetic flowmeter, a third electromagnetic flowmeter and a pressure transmitter on the water supply pipeline; install a return water pipeline on the water supply pipeline between the variable frequency centrifugal pump and the first control valve, and install a fourth control valve on the return water pipeline;

[0030] S4: Connect the cables of the first electromagnetic flowmeter, the second electromagnetic flowmeter, the third electromagnetic flowmeter, the pressure transmitter, the first pressure sensor, the second pressure sensor and the third pressure sensor to a data acquisition device, use a power supply to power the variable frequency centrifugal pump and the data acquisition device, and check and debug each device;

[0031] S5: lowering the drill rod, and placing the upper water stop plug, the steel flower pipe and the lower water stop plug at the designated test position by increasing the number of the drill rods;

[0032] S6: starting the pressurizing device, and applying pressure to the lower water stop plug and the upper water stop plug in sequence through the pressurizing pipe, so that the lower water stop plug and the upper water stop plug are pressurized to expand outwards and cling to the hole wall, thereby sealing the test section;

[0033] S7: Turn on the variable frequency centrifugal pump, inject water through the water supply pipeline to increase pressure, and display and collect real-time pressure and flow data through the data acquisition device; wherein,

[0034] S8: If the data of the second pressure sensor increases, and the data of the first pressure sensor and the third pressure sensor remain basically unchanged, it means that the sealing of the test section is good and no leakage occurs, and water injection and pressurization are continued; if the data of the second pressure sensor increases, and the data of the first pressure sensor and the third pressure sensor also increase significantly, it means that leakage occurs in the test section, and it is necessary to increase the pressure of the pressurizing device, or stop water injection, turn off the pressurizing device, take the device out of the borehole, check the sealing of each part, and then repeat steps S1 to S8;

[0035] S9: If the above situation still occurs after the inspection, it means that there is an obvious hydraulic connection between the test section and the upper or lower side, and the position of the test section needs to be adjusted;

[0036] S10: When the pressure of the test section reaches the test requirements, the variable frequency centrifugal pump is maintained to continuously and stably supply water to form a sealed pressure system; the data acquisition device records the data,

[0037] The test is stopped until the test requirements are met;

[0038] S11: Open the fourth control valve to reduce the pressure in the test system; turn off the variable frequency centrifugal pump and the pressurizing device to reduce the pressure in the upper water stop plug and the lower water stop plug, restore the unexpanded state, and separate from the borehole wall;

[0039] S12: Repeat steps S5 to S11 until the bottom of the borehole is reached or the maximum depth required for the water pressure test is reached.

[0040] The high-precision water pressure test system and use method of the embodiment of the present disclosure, by setting pressure sensors on the outer side of the top of the upper water stop plug and the outer side of the bottom of the lower water stop plug, monitors the pressure data outside the drilling test section in real time during the water pressure test, determines whether there is leakage at the water stop plug, and takes relevant measures accordingly, thereby ensuring the accuracy of the water pressure flow data;

[0041] By placing the pressure sensor at the test section, the pressure data loss due to the drill pipe and water supply pipeline is avoided, thus ensuring the accuracy of the pressure data of the test section.

[0042] The pressure sensor cables inside the steel flower pipe and at the bottom of the lower water stop plug are led out through a three-way sealer and a waterproof joint, which is simple and reliable. It also avoids frequent removal of the plug and pressure sensor and dismantling of the pipeline, greatly reducing labor intensity and improving work efficiency.

[0043] The high-precision water pressure test system of the embodiment of the present disclosure has a simple structure, reasonable design, and low cost. It can accurately monitor the pressure and water supply flow of the test section in real time without changing the conventional water stop plug form, thereby more accurately evaluating the permeability characteristics of the rock and soil body. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a structural schematic diagram of a high-precision water pressure testing system according to an embodiment of the present disclosure;

[0045] Figure 2 It is a structural schematic diagram of a lower water stop plug according to another embodiment of the present disclosure;

[0046] Figure 3 The present invention is a schematic diagram of the cooperation between a three-way sealer and a waterproof joint according to another embodiment of the present invention. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, rather than all the embodiments. The components of the embodiments of the present disclosure described and shown in the drawings here can be arranged and designed in various different configurations.

[0048] Therefore, the following detailed description of the embodiments of the present disclosure provided in the accompanying drawings is not intended to limit the scope of the present disclosure claimed for protection, but merely represents selected embodiments of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present disclosure.

[0049] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In addition, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0050] The electrical components mentioned in this article are all connected to an external main controller and 220V mains electricity, and the main controller can be a conventional known device for controlling a computer or the like.

[0051] In the description of the embodiments of the present disclosure, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the disclosed products are usually placed when in use. They are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present disclosure.

[0052] On the one hand, if Figure 1 and Figure 2 As shown, an embodiment of the present disclosure provides a high-precision water pressure test system 100, and the water pressure test system 100 includes a water supply device, a water stop device and a measuring device. The water supply device includes a water supply pipeline 101 and a steel flower pipe 1012 provided in the drilling test section, the water stop device includes a pressurizing device 102, a pressurizing pipe 1021, an upper water stop plug 1022 and a lower water stop plug 1023, and the measuring device includes a first pressure sensor 103, a second pressure sensor 1031, a third pressure sensor 1032 and a data acquisition device 1033. Among them, the first end of the steel flower pipe 1012 is connected to the lower water stop plug 1023, the second end of the steel flower pipe 1012 is connected to the upper water stop plug 1022, and the upper water stop plug 1022 is also connected to the water outlet of the water supply pipeline 101.

[0053] The pressurizing device 102 is connected to the upper water stop plug 1022 and the lower water stop plug 1023 in sequence through the pressurizing pipe 1021. The first pressure sensor 103 is arranged on the outer side of the top of the upper water stop plug 1022, the second pressure sensor 1031 is arranged inside the steel flower pipe 1012, the third pressure sensor 1032 is arranged on the outer side of the bottom of the lower water stop plug 1023, and each of the sensors is electrically connected to the data acquisition device 1033 to monitor the pressure data inside and outside the drilling test section.

[0054] Specifically, Figure 1 and Figure 2As shown, when the high-precision water pressure test system 100 is working, the pressure device 102 is started, and the pressure device 102 sequentially pressurizes the lower water stop plug 1023 and the upper water stop plug 1022 through the pressure pipe 1021, so that the lower water stop plug 1023 and the upper water stop plug 1022 are pressurized to expand outward, close to the hole wall, and seal the test section. The water enters from the water inlet of the water supply pipeline 101, and then is discharged from the water outlet of the water supply pipeline 101. After being discharged from the water outlet of the water supply pipeline 101, the water flows through the upper water stop plug 1022, the steel flower pipe 1012 and the lower water stop plug 1023 in sequence. Among them, in the process of the water flowing through the steel flower pipe 1012, part of the water will enter the sealed test section formed by the upper and lower water stop plugs through the water permeable holes opened on the side wall of the steel flower pipe 1012. At this time, the first pressure sensor 103 and the third pressure sensor 1032 respectively detect the pressure data outside the sealing test section and transmit the signal to the data acquisition device 1033 for monitoring. The second pressure sensor 1031 detects the pressure data inside the sealing test section and transmits the signal to the data acquisition device 1033 for monitoring.

[0055] The high-precision water pressure test system of the embodiment of the present disclosure can monitor the pressure data outside the drilling test section in real time during the water pressure test through the first pressure sensor and the third pressure sensor, judge whether there is leakage at the water stop plug, and take relevant measures accordingly to ensure the accuracy of the water pressure flow data. The second pressure sensor can monitor the pressure data in the drilling test section in real time, avoiding data errors caused by pipeline pressure loss and ensuring the accuracy of the test section pressure data. The embodiment of the present disclosure has a simple structure, reasonable design, and low cost. It can accurately monitor the test section pressure and water supply flow in real time without changing the conventional water stop plug form, so that the permeability characteristics of the rock and soil body can be more accurately evaluated.

[0056] For example, Figure 1 As shown, the measuring device further includes a plurality of electromagnetic flow components 104 and a pressure transmitter 105. The input ends of the electromagnetic flow components 104 and the pressure transmitter 105 are sequentially arranged in series on the water supply pipeline 101 along the water supply direction of the water supply pipeline 101, and the output ends of the electromagnetic flow components 104 and the pressure transmitter 105 are respectively connected to the data acquisition device 1033.

[0057] It should be noted that the water supply device also includes a water reservoir 106 and a variable frequency centrifugal pump 107 arranged in series in the water supply pipeline 101, and the water pressure test system 100 also includes a power supply 400. The water reservoir 106 is connected to the water inlet of the water supply pipeline 101, and the variable frequency centrifugal pump 107 is located between the water inlet of the water supply pipeline 101 and the first control valve 105. The power supply 400 is used to supply power to the variable frequency centrifugal pump 107 and the data acquisition device 1033. The data acquisition device 1033 is internally provided with a PLC controller. When in use, the pressure transmitter 105, the first pressure sensor 103, the second pressure sensor 1031 and the third pressure sensor 1032 cooperate to detect the pressure changes inside and outside the drilling test section, and at the same time, the formula is used. and

[0058] That is, y"=(y)

[0059] The first-order derivative and the second-order derivative inside and outside the drilling test section are calculated. After the calculation is completed, the variable frequency centrifugal pump 107 is controlled by the PLC controller to achieve constant pressure stability to ensure the accuracy of the data during use. It should be further explained that, due to the difference in the physical properties of the underground rock mass at the test sections at different positions, in order to meet the requirements of the variable frequency centrifugal pump to achieve constant pressure stability control, it is necessary to monitor the values ​​of the pressure inside and outside the test section. According to the monitoring situation, the calculation is fed back to the PLC controller. The frequency conversion of the variable frequency centrifugal pump is reflected in the changes of the first-order derivative and the second-order derivative. This process may be non-steady-state. The frequency conversion and PLC control are used to perform real-time micro-adjustment control to achieve constant pressure control. The above first-order derivative formula is specifically a calculation of the pressure change in the test section, where y represents the pressure value and x represents time. The above second-order derivative formula is specifically a calculation of the pressure outside the test section, where y represents the pressure value and x represents time. In this way, the monitoring of the inside and outside of the test section is realized respectively through the calculation of the first-order derivative and the second-order derivative, so as to better ensure the sealing of the test section.

[0060] Furthermore, if Figure 1 As shown, the electromagnetic flow component 104 includes a first electromagnetic flowmeter 1041, a second electromagnetic flowmeter 1042 and a third electromagnetic flowmeter 1043. The input ends of the first electromagnetic flowmeter 1041, the second electromagnetic flowmeter 1042 and the third electromagnetic flowmeter 1043 are sequentially arranged in series on the water supply pipeline 101 along the water supply direction of the water supply pipeline 101, and the output ends of the first electromagnetic flowmeter 1041, the second electromagnetic flowmeter 1042 and the third electromagnetic flowmeter 1043 are respectively connected to the data acquisition device 1033.

[0061] Specifically, Figure 1As shown, a first electromagnetic flowmeter 1041, a second electromagnetic flowmeter 1042, a third electromagnetic flowmeter 1043 and a pressure transmitter 105 are sequentially arranged in series on the water supply pipeline 101 along its water supply direction, and the three electromagnetic flowmeters and the pressure transmitter are also respectively connected to the data acquisition device 1033. The three electromagnetic flowmeters cooperate with the pressure transmitter 105 to measure the flow data in the water supply pipeline 101 and transmit the signal to the data acquisition device 1033. By setting the three electromagnetic flowmeters to different ranges, the water flow data in the water supply pipeline 101 can be measured more accurately.

[0062] Furthermore, if Figure 1 As shown, the water pressure test system 100 further includes a first control valve 105, a second control valve 1051 and a third control valve 1052 which are serially arranged in the water supply pipeline 101. The first control valve 105 is located between the water inlet of the water supply pipeline 101 and the first electromagnetic flowmeter 1041, the second control valve 1051 is located between the first electromagnetic flowmeter 1041 and the second electromagnetic flowmeter 1042, and the third control valve 1052 is located between the second electromagnetic flowmeter 1042 and the third electromagnetic flowmeter 1043.

[0063] The water pressure test system 100 further includes a first branch 200 connected in parallel to the second control valve 1051 and a second branch 300 connected in parallel to the third control valve 1052. The input end of the second electromagnetic flowmeter 1042 is located between the branch control valve (not marked in the figure) of the first branch 200 and the second control valve 1051, and the input end of the third electromagnetic flowmeter 1043 is located between the branch control valve (not marked in the figure) of the second branch 300 and the third control valve 1052.

[0064] As a specific example, Figure 1 As shown, the first electromagnetic flowmeter 1041, the second electromagnetic flowmeter 1042 and the third electromagnetic flowmeter 1043 can be set as a 100L range intelligent flowmeter, a 20L range intelligent flowmeter and a 5L range intelligent flowmeter respectively. Of course, the three electromagnetic flowmeters can also be set to other different ranges respectively. This embodiment does not make specific restrictions on this. The following is a specific 100L range intelligent flowmeter, a 20L range intelligent flowmeter and a 5L range intelligent flowmeter for explanation:

[0065] During the test, when the flow rate is greater than 100L / min, close the branch control valve on the first branch 200 and the branch control valve on the second branch 300, so that the 100L range intelligent flowmeter measures the water flow. When the flow rate is less than 100L / min, close the second control valve 1051, the third control valve 1052 and the branch control valve on the second branch 300, so that the water flow is detected by the 20L range intelligent flowmeter. When the flow rate is lower than 20L / min, close the branch control valve on the first branch 200 and the third control valve 1052, so that the water flow is measured by the 5L range intelligent flowmeter. This allows accurate detection of different flow rates.

[0066] For example, Figure 1 As shown, the water pressure test system 100 further includes a return water pipeline 108 connected in series with the water supply pipeline 101, and a fourth control valve 1081 connected in series with the return water pipeline 108. The water inlet of the return water pipeline 108 is located between the variable frequency centrifugal pump 107 and the first control valve 105, and the water outlet of the return water pipeline 108 is connected to the water reservoir 106.

[0067] Specifically, Figure 1 As shown, when the test is finished, by opening the fourth control valve 1081 on the return water pipeline 108, the water supply pipeline 101 can be drained, and the discharged water can flow into the water reservoir 106. This setting can reduce the pressure in the test system 100, restore the embolism state, and recycle the water.

[0068] For example, Figure 1 As shown, the water supply device further includes at least one drill rod 109. The top of the drill rod 109 is connected to the water outlet of the water supply pipeline 101, and the bottom of the drill rod 109 is connected to the top of the upper water stop plug 1022. By adjusting the number of drill rods 109, the length of the test section of the water pressure test can be adjusted, and the specific number of drill rods can be set according to actual needs.

[0069] For example, Figure 1 and Figure 2 As shown, the water pressure test system 100 further includes a protective cover 700 disposed at the bottom of the lower water stop plug 1023, and the third pressure sensor 1032 is connected to the bottom of the lower water stop plug 1023 through a waterproof joint 500 and arranged in the protective cover 700. By providing the waterproof joint and the protective cover at the bottom of the lower water stop plug, the third pressure sensor can be double-protected to prevent external water leakage from affecting the detection accuracy of the third pressure sensor.

[0070] For example, Figure 1 and Figure 3 As shown, the water pressure test system 100 also includes a three-way sealer 110. The first opening 111 of the three-way sealer 110 is connected to the bottom of the drill pipe 109, and the second opening 112 of the three-way sealer 110 is connected to the top of the upper water stop plug 1022. And, the first pressure sensor 103, the second pressure sensor 1031 and the third pressure sensor 1032 are all connected to the data acquisition device 1033 through cables 600. The cables 600 of the second pressure sensor 1031 and the third pressure sensor 1032 pass through the third opening 113 of the three-way sealer 110 and are connected to the data acquisition device 1033 through a waterproof connector 500.

[0071] Specifically, Figure 1 As shown, the cable 600 of the first pressure sensor 103 is directly connected to the data acquisition device 1033. The cable 600 of the second pressure sensor 1031 extends inside the steel flower tube 1012 and passes through the upper water stop plug 1022 and the inside of the three-way sealer 110 in sequence, and finally passes through the waterproof joint 500 set at the third opening 113 of the three-way sealer 110 and is connected to the data acquisition device 1033. The cable 600 of the third pressure sensor 1032 passes through the waterproof joint 500 set at the bottom of the lower water stop plug 1023, the lower water stop plug 1023, the steel flower tube 1012, the upper water stop plug 1022 and the inside of the three-way sealer 110 in sequence, and finally passes through the waterproof joint 500 set at the third opening 113 of the three-way sealer 110 and is connected to the data acquisition device 1033.

[0072] The high-precision water pressure testing system of the embodiment of the present disclosure is simple and reliable, and avoids frequent removal of plugs and pressure sensors and dismantling of pipelines, thereby greatly reducing labor intensity and improving work efficiency.

[0073] On the other hand, an embodiment of the present disclosure provides a method for using a water pressure test system, wherein the water pressure test system is the high-precision water pressure test system 100 described above. The specific structure of the high-precision water pressure test system 100 can be referred to the relevant records above, and will not be described in detail here. The method for using the water pressure test system includes:

[0074] S1: Determine the location and length of the test section and the placement of the water stop plug based on the results of the drilling core and ultrasonic imaging in the hole.

[0075] S2: The second pressure sensor 1031 is fixed inside the steel flower tube 1012, and the drill rod 109 is connected to the upper end of the steel flower tube 1012 according to the length of the test section. The third pressure sensor 1032 is fixed in the protective cover 700 at the bottom of the lower water stop plug 1023, and the cable 600 passes through the waterproof joint 500 at the bottom of the lower water stop plug 1023, the lower water stop plug 1023 and the steel flower tube 1012. The cables 600 of the second pressure sensor 1031 and the third pressure sensor 1032 pass through the upper water stop plug 1022 and the three-way sealer 110, and the steel flower tube 1012 and the upper water stop plug 1022 are connected, and the three-way sealer 110 is connected to the upper water stop plug 1022. The pressurizing device 102, the upper water stop plug 1022 and the lower water stop plug 1023 are connected through the pressurizing pipe 1021. The first pressure sensor 103 is fixed to the outer side of the top of the upper water stop plug 1022. The waterproof joint 500 of the three-way sealer 110 is tightened to make it sealed.

[0076] S3: The drill pipe 109 is connected to the three-way sealer 110, and the top of the drill pipe 109 is connected to the water supply pipeline 101. The other end of the water supply pipeline 101 is connected to the water storage tank 106, and the water supply pipeline 101 is installed with a variable frequency centrifugal pump 107, a first electromagnetic flowmeter 1041, a second electromagnetic flowmeter 1042, a third electromagnetic flowmeter 1043 and a pressure transmitter 105. A return water pipeline 108 is installed on the water supply pipeline 101 between the variable frequency centrifugal pump 107 and the first control valve 1041, and a fourth control valve 1081 is installed on the return water pipeline 108.

[0077] S4: Connect the cables 600 of the first electromagnetic flowmeter 1041, the second electromagnetic flowmeter 1042, the third electromagnetic flowmeter 1043, the pressure transmitter 105, the first pressure sensor 103, the second pressure sensor 1031 and the third pressure sensor 1032 to the data acquisition device 1033, use the power supply 400 to power the variable frequency centrifugal pump 107 and the data acquisition device 1033, and check and debug each device.

[0078] S5: lowering the drill rod 109, and placing the upper water stop plug 1022, the steel flower pipe 1012 and the lower water stop plug 1023 at the designated test position by increasing the number of the drill rods 109.

[0079] S6: Start the pressurizing device 102, and pressurize the lower water stop plug 1023 and the upper water stop plug 1022 in sequence through the pressurizing pipe 1021, so that the lower water stop plug 1023 and the upper water stop plug 1022 are pressurized to expand outwards and cling to the hole wall to seal the test section.

[0080] S7: Turn on the variable frequency centrifugal pump 107, inject water through the water supply pipeline 101 to increase the pressure, and display and collect real-time pressure and flow data through the data acquisition device 1033.

[0081] in,

[0082] S8: If the data of the second pressure sensor 1031 increases, and the data of the first pressure sensor 103 and the third pressure sensor 1032 remain basically unchanged, it means that the sealing of the test section is good and no leakage occurs, and water injection and pressurization are continued. If the data of the second pressure sensor 1031 increases, and the data of the first pressure sensor 103 and the third pressure sensor 1032 also increase significantly, it means that leakage occurs in the test section, and it is necessary to increase the pressure of the pressurizing device 102, or stop water injection, turn off the pressurizing device 102, take the device out of the borehole, check the sealing of each part, and then repeat steps S1 to S8.

[0083] S9: If the above situation still occurs after the inspection, it means that there is an obvious hydraulic connection between the test section and the upper or lower side, and the position of the test section needs to be adjusted.

[0084] S10: When the pressure of the test section reaches the test requirements, the variable frequency centrifugal pump 107 is maintained to continuously and stably supply water to form a sealed pressure system. The data acquisition device 1033 records data until the test requirements are met and the test is stopped.

[0085] S11: Open the fourth control valve 1081 to reduce the pressure in the test system 100. Close the variable frequency centrifugal pump 107 and the pressurizing device 102 to reduce the pressure in the upper water stop plug 1022 and the lower water stop plug 1023, restore the unexpanded state, and separate from the borehole wall.

[0086] S12: Repeat steps S5 to S11 until the bottom of the borehole is reached or the maximum depth required for the water pressure test is reached.

[0087] The method for using the water pressure test system of the embodiment of the present disclosure is to set pressure sensors on the outer side of the top of the upper water stop plug and the outer side of the bottom of the lower water stop plug to monitor the pressure data outside the drilling test section in real time during the water pressure test, determine whether there is leakage at the water stop plug, and take relevant measures accordingly to ensure the accuracy of the water pressure flow data.

[0088] By arranging the pressure sensor at the test section, the pressure data loss due to the drill pipe and the water supply pipeline is avoided, thereby ensuring the accuracy of the pressure data of the test section.

[0089] The pressure sensor cables inside the steel flower pipe and at the bottom of the lower water stop plug are led out through a three-way sealer and a waterproof joint. This is simple and reliable, and avoids frequent removal of plugs and pressure sensors and dismantling of pipelines, greatly reducing labor intensity and improving work efficiency.

[0090] The method for using the water pressure test system of the embodiment of the present disclosure is reasonably designed and low-cost. It can accurately monitor the pressure and water supply flow of the test section in real time without changing the form of the conventional water stop plug, thereby more accurately evaluating the permeability characteristics of the rock and soil body.

[0091] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present disclosure, but the present disclosure is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and substance of the present disclosure, and these modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. A high-precision water pressure test system, characterized in that: The water pressure test system includes a water supply device, a water stop device and a measuring device; The water supply device includes a water supply pipeline and a steel flower pipe arranged in the drilling test section, the water stop device includes a pressurizing device, a pressurizing pipe, an upper water stop plug and a lower water stop plug, and the measuring device includes a first pressure sensor, a second pressure sensor, a third pressure sensor and a data acquisition device; wherein, The first end of the steel flower pipe is connected to the lower water stop plug, the second end of the steel flower pipe is connected to the upper water stop plug, and the upper water stop plug is also connected to the water outlet of the water supply pipeline; the pressurizing device is connected to the upper water stop plug and the lower water stop plug in sequence through the pressurizing pipe; the first pressure sensor is arranged on the outside of the top of the upper water stop plug, the second pressure sensor is arranged inside the steel flower pipe, the third pressure sensor is arranged on the outside of the bottom of the lower water stop plug, and each of the sensors is electrically connected to the data acquisition device to monitor the pressure data inside and outside the drilling test section.

2. The high-precision water pressure test system according to claim 1 is characterized in that: The measuring device also includes a plurality of electromagnetic flow components and a pressure transmitter; The input ends of the electromagnetic flow element and the pressure transmitter are sequentially arranged in series on the water supply pipeline along the water supply direction of the water supply pipeline, and the output ends of the electromagnetic flow element and the pressure transmitter are respectively connected to the data acquisition device.

3. The high-precision water pressure test system according to claim 2 is characterized in that: The electromagnetic flow meter comprises a first electromagnetic flow meter, a second electromagnetic flow meter and a third electromagnetic flow meter; The input ends of the first electromagnetic flowmeter, the second electromagnetic flowmeter and the third electromagnetic flowmeter are sequentially arranged in series in the water supply pipeline along the water supply direction of the water supply pipeline, and the output ends of the first electromagnetic flowmeter, the second electromagnetic flowmeter and the third electromagnetic flowmeter are respectively connected to the data acquisition device.

4. The high-precision water pressure test system according to claim 3 is characterized in that: The water pressure test system also includes a first control valve, a second control valve and a third control valve which are arranged in series on the water supply pipeline; The first control valve is located between the water inlet of the water supply pipeline and the first electromagnetic flowmeter, the second control valve is located between the first electromagnetic flowmeter and the second electromagnetic flowmeter, and the third control valve is located between the second electromagnetic flowmeter and the third electromagnetic flowmeter; and, The water pressure test system also includes a first branch connected in parallel to the second control valve and a second branch connected in parallel to the third control valve; wherein the input end of the second electromagnetic flowmeter is located between the branch control valve of the first branch and the second control valve, and the input end of the third electromagnetic flowmeter is located between the branch control valve of the second branch and the third control valve.

5. The high-precision water pressure test system according to claim 4, characterized in that: The water supply device also includes a water reservoir and a variable frequency centrifugal pump connected in series to the water supply pipeline, and the water pressure test system also includes a power supply; The water reservoir is in communication with the water inlet of the water supply pipeline, and the variable frequency centrifugal pump is located between the water inlet of the water supply pipeline and the first control valve; The power supply is used to supply power to the variable frequency centrifugal pump and the data acquisition device.

6. The high-precision water pressure test system according to claim 5, characterized in that: The water pressure test system further comprises a return water pipeline connected in series with the water supply pipeline, and a fourth control valve connected in series with the return water pipeline; The water inlet of the water return pipeline is located between the variable frequency centrifugal pump and the first control valve, and the water outlet of the water return pipeline is communicated with the water reservoir.

7. The high-precision water pressure testing system according to any one of claims 1 to 6, characterized in that: The water supply device also includes at least one drill rod; The top of the drill rod is connected to the water outlet of the water supply pipeline, and the bottom of the drill rod is connected to the top of the upper water stop plug.

8. The high-precision water pressure test system according to claim 7, characterized in that: The water pressure test system also includes a protective cover arranged at the bottom of the lower water stop plug, and the third pressure sensor is connected to the bottom of the lower water stop plug through a waterproof joint and arranged in the protective cover.

9. The high-precision water pressure test system according to claim 7, characterized in that: The water pressure test system also includes a three-way sealer; The first opening of the three-way sealer is connected to the bottom of the drill pipe, and the second opening of the three-way sealer is connected to the top of the upper water stop plug; and, The first pressure sensor, the second pressure sensor and the third pressure sensor are all connected to the data acquisition device through cables; wherein the cables of the second pressure sensor and the third pressure sensor pass through the third opening of the three-way sealer and are connected to the data acquisition device through a waterproof connector.

10. A method for using a water pressure test system, wherein the water pressure test system is the high-precision water pressure test system according to any one of claims 1 to 9, characterized in that: include: S1: Determine the location and length of the test section and the placement of the water stop plug based on the drilling core and in-hole ultrasonic imaging results; S2: Fix the second pressure sensor inside the steel flower pipe, and connect the drill rod to the upper end of the steel flower pipe according to the length of the test section; fix the third pressure sensor in the protective cover at the bottom of the lower water stop plug, and pass the cable through the waterproof joint at the bottom of the lower water stop plug, the lower water stop plug and the steel flower pipe; pass the cables of the second pressure sensor and the third pressure sensor through the upper water stop plug and the three-way sealer, connect the steel flower pipe and the upper water stop plug, and connect the three-way sealer to the upper water stop plug; connect the pressurizing equipment, the upper water stop plug and the lower water stop plug through the pressurizing pipe; fix the first pressure sensor on the outside of the top of the upper water stop plug; tighten the waterproof joint of the three-way sealer to make it sealed; S3: Connect the drill pipe to the three-way sealer, and connect the top of the drill pipe to the water supply pipeline; connect a water reservoir to the other end of the water supply pipeline, and install a variable frequency centrifugal pump, a first electromagnetic flowmeter, a second electromagnetic flowmeter, a third electromagnetic flowmeter and a pressure transmitter on the water supply pipeline; install a return water pipeline on the water supply pipeline between the variable frequency centrifugal pump and the first control valve, and install a fourth control valve on the return water pipeline; S4: Connect the cables of the first electromagnetic flowmeter, the second electromagnetic flowmeter, the third electromagnetic flowmeter, the pressure transmitter, the first pressure sensor, the second pressure sensor and the third pressure sensor to a data acquisition device, use a power supply to power the variable frequency centrifugal pump and the data acquisition device, and check and debug each device; S5: lowering the drill rod, and placing the upper water stop plug, the steel flower pipe and the lower water stop plug at the designated test position by increasing the number of the drill rods; S6: starting the pressurizing device, and applying pressure to the lower water stop plug and the upper water stop plug in sequence through the pressurizing pipe, so that the lower water stop plug and the upper water stop plug are pressurized to expand outwards and cling to the hole wall, thereby sealing the test section; S7: Turn on the variable frequency centrifugal pump, inject water through the water supply pipeline to increase pressure, and display and collect real-time pressure and flow data through the data acquisition device; wherein, S8: If the data of the second pressure sensor increases, and the data of the first pressure sensor and the third pressure sensor remain basically unchanged, it means that the sealing of the test section is good and no leakage occurs, and water injection and pressurization are continued; if the data of the second pressure sensor increases, and the data of the first pressure sensor and the third pressure sensor also increase significantly, it means that leakage occurs in the test section, and it is necessary to increase the pressure of the pressurizing device, or stop water injection, turn off the pressurizing device, take the device out of the borehole, check the sealing of each part, and then repeat steps S1 to S8; S9: If the above situation still occurs after the inspection, it means that there is an obvious hydraulic connection between the test section and the upper or lower side, and the position of the test section needs to be adjusted; S10: When the pressure of the test section reaches the test requirements, the variable frequency centrifugal pump is maintained to continuously and stably supply water to form a sealed pressure system; the data acquisition device records data until the test requirements are met and the test is stopped; S11: Open the fourth control valve to reduce the pressure in the test system; turn off the variable frequency centrifugal pump and the pressurizing device to reduce the pressure in the upper water stop plug and the lower water stop plug, restore the unexpanded state, and separate from the borehole wall; S12: Repeat steps S5 to S11 until the bottom of the borehole is reached or the maximum depth required for the water pressure test is reached.

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