CN214616507U - Water-retaining pressure relief device suitable for ground stress test of deep water level drilling - Google Patents

Abstract

The utility model provides a protect water pressure relief device suitable for deep water position drilling ground stress test, including ground high pressure water pipe, high pressure water pump, arrange the last packer in the drilling in, lower packer, the push-and-pull of being connected with the lower extreme of drilling rod protects water pressure relief device, push-and-pull protects water pressure relief device includes the main part, locate the valve plug sliding cavity of main part, packer fluid passage, pressure release fluid passage, well core rod fluid passage and push-and-pull valve plug, be equipped with built-in piston sliding cavity and built-in piston in the push-and-pull valve plug, built-in piston lower part is equipped with spring guide bar and prestressing spring, spring guide bar below is equipped with the piston stopper who is fixed in the center pipe interface, the center pipe interface is connected with the upper end center of last packer, the drilling rod upper end is connected with ground high pressure water pipe, high pressure water pump through crossover sub-pipe, be equipped with manometer and data acquisition system on the ground high pressure water pipe. The utility model discloses can realize among the deep water level drilling ground stress test packer quick pressure release, preserve the purpose that drilling rod flood peak and pressure channel switched.

Description

Water-retaining pressure relief device suitable for ground stress test of deep water level drilling

Technical Field

The utility model relates to a rock mass mechanics is experimental technical field, specifically is a pressure relief device that protects water suitable for deep water level drilling ground stress test.

Background

The stress test of the conventional hydraulic fracturing method is mainly divided into a single-pipe method and a double-pipe method. The single-pipe method realizes the pressure channel switching between the packer and the testing section by internally connecting a push-pull valve between the drill pipe and the double-plug packer, is suitable for continuous and rapid testing of deep drilling holes with high water level (generally the water level is not more than 50m), and is simple to operate. The double-pipe method forms two pressure channels by connecting a long and thin high-pressure water pipe with the drill rod outside the packer, is suitable for shallow drilling hole testing, and is complex to operate. Along with underground works's buried depth is bigger and bigger, and the geological drilling of big buried depth, deep water level can the ubiquitous, generally chooses single-pipe method for use to test, but the pressure that forms towards the drilling rod water injection in-process inside and outside flood peak of drilling rod difference can lead to the packer independently to expand to fix unable removal on the pore wall, consequently needs supporting pressure relief device to carry out the pressure release to the packer alone, and current pressure release method is inefficiency, and the test duration that needs is far away the drilling of super high water level.

At present, the pressure relief modes with higher operability are mainly divided into two types: the first pressure relief mode cannot be continuously tested after the pressure of the packer is relieved, the packer needs to be completely lifted to the ground through a drill rod after a test section is completed, the pressure relief device is manually restored, then the drill rod is connected again and is placed to a specified position through hoisting and hoisting of a drilling machine, water is injected into the drill rod again, the pressure relief mode is lowest in efficiency, and a large amount of time and manpower are used in a water injection stage before connection, disassembly and testing in the repeated hoisting process; the stroke of the piston in the pressure relief device is finely adjusted through the accurate control drilling rod that takes off and land on ground in the second kind of pressure relief mode thereby makes drilling rod internal water flow in drilling, reduce the inside and outside flood peak of drilling rod poor, reach the purpose of packer pressure relief, accessible rig hoist after the pressure relief is hung and is placed next test position and carry out the continuous test, nevertheless need again toward the interior water injection of drilling rod before the test, this pressure relief mode is first kind of mode efficiency relatively improves to some extent, need not hoist the drilling rod repeatedly, but the water injection before its pressure relief in-process drilling rod drains and retest still will occupy very long period. Although above two kinds of modes have reached the purpose of pressure release, efficiency is very low, and test site clear water resource often is more scarce, consequently for save time, manpower and material resources input, improves efficiency of software testing, reduces test cost, utility model a hydraulic fracturing method ground stress testing arrangement who is fit for deep water level drilling high efficiency and easily operates has important meaning.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome the weak point that has the background art to a pressure relief device that protects water suitable for deep water position drilling ground stress test is provided, through design push-and-pull pressure relief integrated device that protects water, the control drilling rod goes up and down to link integrated device and realizes packer quick pressure release, the purpose of preserving drilling rod flood peak and pressure channel switching in deep water position drilling ground stress test.

In order to solve the above problem, the utility model adopts the technical scheme that:

the utility model provides a protect water pressure relief device suitable for deep water level drilling ground stress test, includes ground high pressure water pipe, high pressure water pump, arranges last packer and lower packer in the drilling in, goes up the center of packer and lower packer and connects with fracturing section center floral tube, goes up the rubber barrel of packer and lower packer and connects oil pipe intercommunication, its characterized in that through last lower packer: the push-pull water-retaining pressure relief device comprises a main body, a valve plug sliding cavity arranged in the main body, a packer fluid channel, a pressure relief fluid channel, a central rod fluid channel and a push-pull valve plug which is connected with the drill rod and can move up and down in the valve plug sliding cavity, a built-in piston sliding cavity and a built-in piston capable of moving up and down in the built-in piston sliding cavity are arranged in the push-pull valve plug, a spring guide rod and a pre-stressed spring sleeved on the spring guide rod are arranged at the lower part of the built-in piston, a piston limiter fixed at a central pipe interface is arranged below the spring guide rod to limit the spring guide rod, and the central pipe interface is used as a central water outlet of the push-pull water-retaining pressure relief device and is connected with the upper end center of the upper packer; the upper end of the drill rod is connected with a ground high-pressure water pipe through a conversion joint, the ground high-pressure water pipe is connected with a ground high-pressure water pump, and a pressure gauge and a data acquisition system for monitoring pressure are arranged on the ground high-pressure water pipe.

Further, when the built-in push-pull valve plug is stretched in the initial state, the rubber cylinder of the upper packer is communicated with the drill hole through the packer fluid channel, the built-in piston sliding cavity and the pressure relief fluid channel to form a pressure relief loop; when the push-pull valve plug is stretched in a pressurized state, the built-in piston slides downwards to close the pressure relief fluid channel to form a partition with a drilling space, and pressure water in a central channel of the drill rod enters the upper packer through the packer fluid channel to achieve the purpose of seat sealing; after the seat sealing is finished, slowly dropping a drill rod, closing a push-pull valve plug under the action of the self weight of the drill rod and the frictional resistance of the packer, connecting the pressure water of a central channel of the drill rod with a central pipe interface through a central rod fluid channel, and carrying out a fracturing test at the moment; after the fracturing test is accomplished, slowly promote the drilling rod and make the push-and-pull valve plug tensile completely, at this moment under the frictional resistance of built-in piston sliding cavity sealing washer and prestressing spring's effort, the guarantor's pressure relief device of push-and-pull resumes initial condition, and completion pressure release in packer pressure rivers flow into the drilling.

Furthermore, the push-pull water-retaining pressure relief device further comprises a drill rod interface used for being connected with a drill rod, a connecting cavity communicated with the built-in piston sliding cavity and the drill rod interface is arranged on the upper portion of the push-pull valve plug, the connecting cavity can guide water flow of the drill rod into the built-in piston sliding cavity through the drill rod, and then the built-in piston is pushed to move downwards.

Furthermore, three groups of water outlet holes are formed in the upper, middle and lower cross sections of the side wall of the pull valve plug, namely a first water outlet hole in the side wall of the push-pull valve plug, a second water outlet hole in the side wall of the push-pull valve plug and a third water outlet hole in the side wall of the push-pull valve plug; a water outlet hole in the side wall of the built-in piston is formed in one cross section of the built-in piston, a second water outlet hole in the side wall of the push-pull valve plug and a third water outlet hole in the side wall of the pull valve plug are communicated with a sliding cavity of the built-in piston, and a first water outlet hole in the side wall of the push-pull valve plug is positioned at the upper part of the built-in piston and is not communicated with the sliding cavity of the piston; when the built-in push-pull valve plug is stretched in an initial state, a water outlet hole in the side wall of the built-in piston and a second water outlet hole in the side wall of the push-pull valve plug are communicated with a packer fluid channel arranged in the main body, one end of the packer fluid channel is communicated with the second water outlet hole in the side wall of the push-pull valve plug, the other end of the packer fluid channel is communicated with an upper packer connecting oil pipe through an upper packer oil pipe interface, and the upper packer connecting oil pipe is connected with a rubber cylinder of an upper packer; the third water outlet hole on the side wall of the push-pull valve plug is communicated with a pressure relief fluid channel arranged on the main body, one end of the pressure relief fluid channel is communicated with an upper packer through the third water outlet hole on the side wall of the push-pull valve plug, a built-in piston sliding cavity, the water outlet hole on the side wall of the built-in piston, the second water outlet hole on the side wall of the push-pull valve plug and the fluid channel of the packer, and the other end of the pressure relief fluid channel is provided with a pressure relief hole check plate to be communicated with a drilling space, so that the pressure relief loop is formed; when the push-pull valve plug is stretched in a pressurized state, the built-in piston slides downwards to seal and separate a third water outlet hole in the side wall of the push-pull valve plug, so that the pressure relief fluid channel is closed and a partition is formed between the pressure relief fluid channel and a drilling space; after the seat seal is completed, the drill rod slowly falls, under the action of the self weight of the drill rod and the frictional resistance of the packer, the push-pull valve plug is closed, and the first water outlet hole in the side wall of the push-pull valve plug is communicated with a central rod fluid channel arranged in the main body.

Further, the main body is assembled by an upper main body and a lower main body.

The utility model discloses an optimize test procedure and equipment combination, realized low-cost efficient deep water level drilling stress test fast, had following advantage: (1) the pressure of the packer can be quickly relieved regardless of the difference between the internal and external water heads of the drill rod in the test process; (2) after the pressure is released, the test tool can be continuously placed in the next set test section for repeated tests without repeatedly lifting the drill, so that the test time is greatly saved, and the risk of repeatedly lifting the drill up and down is also reduced; (3) the water in the drill rod can be preserved during pressure relief, so that the time required by water discharging and water injection of the drill rod is saved, and the consumption of on-site clear water is greatly reduced; (4) packer pressure release switches with fluid passage and integrates to a device in, and simple structure is practical, can improve efficiency of software testing, reduces test cost.

Drawings

FIG. 1 is a schematic structural view of the water-retaining and pressure-releasing device suitable for the ground stress test of deep water level drilling;

FIG. 2(a) is a schematic view of a transverse cross-sectional structure of the water-retaining and pressure-releasing device pushed and pulled in an initial state after water injection;

fig. 2(b) is a schematic view of the longitudinal section structure of the water-retaining pressure-releasing device pushed and pulled in the initial state after water injection;

FIG. 2(c) is a schematic diagram of the cross-sectional structure of the push-pull water-retaining pressure-releasing device in the packer setting process of the present invention;

fig. 2(d) is a schematic diagram of the longitudinal section structure of the push-pull water-retaining pressure relief device in the test section fracturing process of the utility model;

FIG. 2(e) is a schematic diagram of the transverse cross-sectional structure of the push-pull water-retaining pressure-releasing device in the fracturing process of the test section of the utility model;

FIG. 2(f) is a schematic diagram of the cross-sectional structure of the push-pull water-retaining pressure-releasing device in the pressure-releasing process of the packer of the present invention;

FIG. 3(a) is a schematic cross-sectional structure view of a water-retaining and pressure-releasing device I-I' pushed down in an initial state after water injection;

fig. 3(b) is a schematic cross-sectional structure view of the water-retaining pressure relief device ii-ii' pushed down in the initial state after water injection.

In the figure: 1-high pressure water pump; 2-a data acquisition system; 3-ground high-pressure water pipe; 4-a pressure gauge; 5-a water release ball valve; 6-pipeline joint; 7, a hoisting system; 8, drilling a rod; 9-pushing and pulling the water-retaining pressure relief device; 10, connecting an upper packer with an oil pipe; 11-ground water level; 12-setting a packer; 13, connecting the upper packer and the lower packer with an oil pipe; 14-fracturing section central perforated pipe; 15-lower packer;

9-1-drill rod interface (water inlet); 9-2-push-pull valve plug; 9-3 — upper body; 9-4-sealing ring; 9-5, pushing and pulling a first water outlet hole on the side wall of the valve plug; 9-6-lower body; 9-7-built-in piston; 9-8-packer fluid passages; 9-pushing and pulling the second water outlet hole on the side wall of the valve plug; 9-10-water outlet holes in the side wall of the built-in piston; 9-11-a third water outlet hole on the side wall of the push-pull valve plug; 9-12-pressure relief hole check plate; 9-13-pressure relief fluid channel; 9-14-prestressed spring; 9-15-spring guide rod; 9-16-piston stops; 9-17-water outlet of piston limiter; 9-18-central tube interface; 9-19-packer tubing interface; 9-20-center rod fluid channel; 9-21-a first annular channel; 9-22-second annular groove water channel; 9-23-compression bin with built-in piston spring; 9-24-built-in piston sliding cavity.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Referring to fig. 1 to 3, the present invention is applicable to one embodiment of a water-holding and pressure-releasing device for deep water level borehole ground stress test, and includes a push-pull water-holding and pressure-releasing device, an upper packer 12 and a lower packer 15 on the same vertical axis, the central tube in the packers is completely sealed, and the centers of the upper packer 12 and the lower packer 15 are connected by a fracturing section central perforated pipe 14; the center of the upper end of an upper packer 12 is connected with a central water outlet of a push-pull water-retaining pressure relief device, side water outlets (upper packer oil pipe connectors 9-19) of the push-pull water-retaining pressure relief device are communicated with a rubber cylinder of the upper packer 12 through a high-pressure water pipe (an upper packer is connected with an oil pipe 10), the upper packer 12 is communicated with a rubber cylinder of a lower packer 15 through a high-pressure water pipe (an upper packer is connected with an oil pipe 13), the upper end of the push-pull water-retaining pressure relief device is connected with the lower end of a waterproof drill rod 8, the upper end of the drill rod 8 is connected with a ground high-pressure water pipe 3 through a conversion joint, and the ground high-pressure water pipe 3 is connected with a ground high-pressure water pump 1.

The utility model discloses a key is push-and-pull water conservation pressure release integrated device, need confirm drilling water level degree of depth earlier before the test, then solve built-in piston and preserve the atress problem of drilling rod flood peak. For deep drilling, assuming that the water level is 500m away from the orifice, and the maximum water head pressure generated by the difference between the internal water head and the external water head of the drill rod after water injection is 5MPa, the pressure of the internal water head of the drill rod needs to be balanced by the built-in piston under the common acting force of the friction of the sealing ring and the pre-stressed spring, so that the aim of keeping the drill rod from losing water is fulfilled. The friction force of the sealing ring is mainly related to the size, the material and the number of the sealing ring, and the method mainly adopted here is to determine the sliding critical pressure of the built-in piston through a repeated pressurization test, namely the maximum static friction force generated by the sealing ring to the piston. If the maximum static friction force generated by the sealing ring is smaller than the maximum water head pressure, a pre-stressed spring is required to be additionally arranged to compensate the stress difference generated between the maximum water head pressure and the maximum static friction force, the pressure compensated by the spring can be calculated by F ═ K ·ΔX, wherein K is the spring stiffness coefficient (mainly related to the material, length, diameter, total turns and the like of the spring), and Δ X is the pre-compression displacement of the spring. The stress condition of the sealing ring and the spring is determined according to the water level of the drilled hole, the proper sealing ring and the proper spring are selected to meet the testing condition of the drilled hole at a certain deep water level, and the push-pull water-retaining pressure relief device can be assembled to start testing. The ground high-pressure water pipe 3 is provided with a pressure gauge 4 for monitoring pressure and a data acquisition system 2.

The push-pull water-retaining pressure relief device comprises a main body, a valve plug sliding cavity arranged in the main body and a push-pull valve plug 9-2 which is connected with a drill rod 8 and can move up and down in the valve plug sliding cavity, wherein the main body comprises an upper main body 9-3 and a lower main body 9-6 which are assembled together, internal parts can be conveniently assembled and disassembled, three groups of water outlet holes are arranged on the upper, middle and lower cross sections of the side wall of the push-pull valve plug 9-2, namely a first water outlet hole 9-5 on the side wall of the push-pull valve plug, a second water outlet hole 9-9 on the side wall of the push-pull valve plug and a third water outlet hole 9-11 on the side wall of the push-pull valve plug; the built-in piston sliding cavity 9-24 and the built-in piston 9-7 which can move up and down in the built-in piston sliding cavity 9-24 and is used for storing a drill rod water head are arranged in the push-pull valve plug 9-2, the upper portion of the push-pull valve plug 9-2 is provided with a connecting cavity communicated with the built-in piston sliding cavity 9-24 and a drill rod interface 9-1, and the connecting cavity can guide water flow of a drill rod 8 into the built-in piston sliding cavity 9-24 through the drill rod 8 so as to push the built-in piston 9-7 to move downwards.

One cross section of the built-in piston 9-7 is provided with a group of water outlet holes (the water outlet holes 9-10 on the side wall of the built-in piston). The second water outlet hole 9-9 on the side wall of the push-pull valve plug and the third water outlet hole 9-11 on the side wall of the pull-pull valve plug are communicated with the built-in piston sliding cavity 9-24, and the first water outlet hole 9-5 on the side wall of the push-pull valve plug is positioned at the upper part of the built-in piston 9-7 and is not communicated with the piston sliding cavity 9-24.

The lower part of the built-in piston 9-2 is provided with a spring guide rod 9-15 and a pre-stressed spring 9-14 sleeved on the spring guide rod 9-15, the pre-stressed spring 9-14 is compressed in the downward sliding process of the built-in piston 9-2, and the spring guide rod 9-15 can extend into a piston stopper 9-16 of which the lower part is fixed in a central pipe interface 9-18; and a sealing ring is arranged between the water outlet holes on the side wall at different positions, so that the fluid is ensured to flow only from the water outlet holes and not to circulate on the surface of the side wall.

When the built-in push-pull valve plug 9-2 is stretched in an initial state, a water outlet hole 9-10 of the side wall of the built-in piston and a second water outlet hole 9-9 of the side wall of the push-pull valve plug are communicated with a packer fluid channel 9-8 arranged on the main body, one end of the packer fluid channel 9-8 is communicated with the second water outlet hole 9-9 of the side wall of the push-pull valve plug, and the other end of the packer fluid channel is communicated with an upper packer connecting oil pipe 10 through an upper packer oil pipe interface 9-19; the third water outlet hole 9-11 on the side wall of the push-pull valve plug is communicated with a pressure relief fluid channel 9-13 arranged on the main body, the second water outlet hole 9-9 on the side wall of the push-pull valve plug and the third water outlet hole 9-11 on the side wall of the pull valve plug are communicated with a built-in piston sliding cavity 9-24, one end of the pressure relief fluid channel 9-13 is communicated with a packer through the third water outlet hole 9-11 on the side wall of the pull valve plug, the built-in piston sliding cavity 9-24, the water outlet hole 9-10 on the side wall of the built-in piston, the second water outlet hole 9-9 on the side wall of the push-pull valve plug and a packer fluid channel 9-8, and the other end is provided with a pressure relief hole check plate 9-12 to be communicated with a drilling space, so as to form a pressure relief loop;

when the push-pull valve plug 9-2 is stretched in a pressurized state, the built-in piston 9-7 slides downwards, the third water outlet hole 9-11 in the side wall of the push-pull valve plug is sealed and isolated, the pressure relief fluid channel 9-13 is closed, an isolation is formed between the pressure relief fluid channel and a drilling space, and pressure water in a central channel of the drill rod 8 enters the upper packer 12 through the packer fluid channel 9-8 to achieve the purpose of seat sealing; after the seat sealing is finished, slowly dropping a drill rod 8, closing a push-pull valve plug 9-2 under the action of the self weight of the drill rod 8 and the frictional resistance of the packer, communicating a first water outlet hole 9-5 on the side wall of the push-pull valve plug with a central rod fluid channel 9-20 arranged on a main body, connecting a lower end outlet of the central rod fluid channel 9-20 with a central pipe interface 9-18, connecting the central pipe interface 9-18 serving as a central water outlet of a push-pull water-retaining pressure relief device with the upper end center of an upper packer 12, and carrying out a fracturing test at the moment; after the fracturing test is finished, the drill rod 8 is slowly lifted to enable the push-pull valve plug 9-2 to be completely stretched, at the moment, under the frictional resistance of a sealing ring in the built-in piston sliding cavity 9-24 and the acting force of the pre-stressed spring 9-14, the push-pull water-retaining pressure relief device is restored to an initial state (namely a pressure relief loop is formed), and pressure water of the packer flows into the drill hole to finish pressure relief.

Use the utility model discloses when carrying out the water conservation pressure release that is applicable to deep water level drilling ground stress test, specifically include following step:

the preparation process comprises the following steps: firstly, connecting a ground stress underground testing device (parts with the labels of 9-15) on the ground according to the figure 1, and then hoisting the whole connected ground stress underground testing device by using a hoisting system 7 and then placing the whole connected ground stress underground testing device at an orifice; connecting a drill rod 8 to a push-pull water-retaining pressure-relieving device (9), and continuously connecting the drill rod until a central perforated pipe 14 of the fracturing section is placed at a specified testing depth; clear water is filled into the drill rod 8, and a water path in the drill rod 8 in an unpressurized state cannot be communicated with the packer based on the action of pushing, pulling, holding and pressure relief devices 9; and finally, the high-pressure water pump 1, the data acquisition system 2, the pressure gauge 4 and the water drain ball valve 5 are communicated with the upper end of the drill rod 8 through the pipeline joint 6 and the ground high-pressure water pipe 3 to form a complete test system.

The test procedure was as follows:

firstly, a pipeline joint 6 connected with a drill rod 8 is lifted by about 1m by using a lifting system 7, so that a push-pull valve plug 9-2 in a push-pull water-retaining and pressure-relieving device 9 is ensured to be in a stretching state and have enough stroke space, and the state of the push-pull water-retaining and pressure-relieving device 9 is shown in fig. 2(a) and 2 (b);

secondly, the high-pressure water pump 1 is gradually pressurized to enable the built-in piston 9-7 to compress the pre-stressed spring 9-14 to gradually slide downwards until the drill pipe waterway is communicated with the packer fluid channel 9-8, and the spring guide rod 9-15 extends into the piston stopper 9-16 to control the compression path of the pre-stressed spring 9-14, wherein the state is shown in figure 2 (c); then, gradually pressurizing to a specified pressure to ensure that the upper packer (12) and the lower packer (15) are expanded and cling to the wall of the drilled hole;

thirdly, operating the hoisting system 7 to enable the drill rod 8 to fall smoothly, after the push-pull valve plug 9-2 of the water-retaining pressure relief device is completely closed, the self weight of the water-full drill rod 8 can be balanced with the frictional resistance generated on the hole wall by the packers (12, 15), so that the drill rod 8 naturally stops descending, limiting the movement of the built-in piston 9-7 by the piston limiter 9-16 at the moment and pushing the built-in piston to reach the top of the built-in piston sliding cavity 9-24, and enabling the state of the push-pull water-retaining pressure relief device (9) to be as shown in figures 2(d) and 2(e), and enabling water in the drill rod to enter the fracturing section central flower tube 14 through the side wall of the push-pull valve plug, the first water outlet hole 9-5 of the side wall of the valve plug, the central rod fluid channel 9-20, the water outlet hole 9-17 of the piston limiter, the central tube interface 9-18 and the central tube of the upper packer 12;

step four, pressurizing and acquiring data of the fracturing section by the high-pressure water pump 1 in the above state; after data acquisition is finished, operating the hoisting system 7 to slowly lift the drill stem 8 until a push-pull valve plug 9-2 in the push-pull water-retaining pressure relief device is in a fully-stretched state, sealing a water head in the drill stem 8 by the built-in piston 9-7 under the friction action of a sealing ring of the push-pull valve plug 9-2 and the prestress action of a prestress spring 9-14, and allowing pressure water in a capsule of the packer (12, 15) to flow into a drill hole along a packer fluid channel 9-8, a second water outlet hole 9-9 in the side wall of the push-pull valve plug, a water outlet hole 9-10 in the side wall of the built-in piston, a built-in piston spring compression bin 9-23, a built-in piston sliding cavity 9-24 and a pressure relief fluid channel 9-13 to achieve the purpose of pressure relief, wherein the state is shown in (f) of fig. 2; the pressure relief hole check plate 9-12 plays a role in one-way outflow of fluid, and prevents the turbid liquid in the hole from flowing back to enter the push-pull water-retaining pressure relief device 9 to cause the faults of water channel blockage and the like; after the pressure of the packers (12 and 15) is completely released, the packer can be restored to the initial state shown in figure 2 (a);

and fifthly, moving the testing device to the next testing section by operating the hoisting system 7 and increasing or decreasing the drill rod 8, and repeating the processes to realize the rapid and continuous testing of the next testing section.

Fig. 3 is a schematic diagram of two important cross sections, which are mainly used for supplementing and explaining the specific distribution of fluid channels of the push-pull water-retaining pressure-relief device 9. The fluid channels (packer fluid channels 9-8 and pressure relief channels 9-13), the side wall water outlets (9-9, 9-11) of the push-pull valve plug and the side wall water outlets (9-10) of the piston with the built-in valve plug are in the state of being on the same axis, and the fluid channels and the side wall water outlets are probably not on the same axis, so that the water outlets (9-9, 9-10, 9-11) are communicated with the fluid channels (9-8, 9-13) mainly through annular groove water channels (9-21, 9-22).

The utility model discloses can greatly save time, manpower and material resources and drop into, and then produce obvious economic benefits, improve the efficiency of probing test, reduce the test cost to the easy operation of this method, equipment requirement is lower, is convenient for popularize and apply on a large scale.

The above description is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are all covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (3)

1. The utility model provides a protect water pressure relief device suitable for deep water level drilling ground stress test, includes ground high pressure water pipe, high pressure water pump, arranges last packer and lower packer in the drilling in, goes up the center of packer and lower packer and connects with fracturing section center floral tube, goes up the rubber barrel of packer and lower packer and connects oil pipe intercommunication, its characterized in that through last lower packer: the push-pull water-retaining pressure relief device comprises a main body, a valve plug sliding cavity arranged in the main body, a packer fluid channel, a pressure relief fluid channel, a central rod fluid channel and a push-pull valve plug which is connected with the drill rod and can move up and down in the valve plug sliding cavity, a built-in piston sliding cavity and a built-in piston capable of moving up and down in the built-in piston sliding cavity are arranged in the push-pull valve plug, a spring guide rod and a pre-stressed spring sleeved on the spring guide rod are arranged at the lower part of the built-in piston, a piston limiter fixed at a central pipe interface is arranged below the spring guide rod to limit the spring guide rod, and the central pipe interface is used as a central water outlet of the push-pull water-retaining pressure relief device and is connected with the upper end center of the upper packer; the upper end of the drill rod is connected with a ground high-pressure water pipe through a conversion joint, the ground high-pressure water pipe is connected with a ground high-pressure water pump, and a pressure gauge and a data acquisition system for monitoring pressure are arranged on the ground high-pressure water pipe.

2. The water-retaining and pressure-relieving device suitable for the ground stress test of the deep water level drill hole as claimed in claim 1, wherein: the push-pull water-retaining pressure relief device further comprises a drill rod interface used for being connected with a drill rod, a connecting cavity communicated with the built-in piston sliding cavity and the drill rod interface is arranged on the upper portion of the push-pull valve plug, water flow of the drill rod can be guided into the built-in piston sliding cavity through the drill rod by the connecting cavity, and then the built-in piston is pushed to move downwards.

3. The water-retaining and pressure-relieving device suitable for the ground stress test of the deep water level drill hole as claimed in claim 1, wherein: the main body is assembled by an upper main body and a lower main body.

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