Hydraulic high-pressure pulsating pressure drive injection device and implementation method

Abstract

The invention discloses a hydraulic high-pressure pulsating pressure drive injection device and an implementation method, the hydraulic high-pressure pulsating pressure drive injection device comprises a one-way ball valve, a piston, an energy storage cylinder, an upper limiting block, a nozzle, a lower limiting block, a packer and an energy storage spring, the upper limiting block and the lower limiting block are arranged in an oil pipe from top to bottom, and the one-way ball valve is arranged between the upper limiting block and the lower limiting block; a nozzle is arranged on the side wall of the oil pipe and located above the lower limiting block, the one-way ball valve is suitable for sliding up and down along the oil pipe, when the one-way ball valve makes contact with the lower limiting block, the one-way ball valve covers the nozzle, a packer is arranged between the oil pipe and the sleeve and located below the lower limiting block, and a piston and an energy storage spring are sequentially arranged in the oil pipe and located below the lower limiting block. An energy storage cylinder is arranged between the oil pipe and the sleeve and located below the packer. The device is of a mechanical structure and is low in failure rate; and underground hydraulic pulsation operation can be completed, the water flooding sweep effect is improved, migration of an oil-water interface in a micro-pore structure is promoted, and the recovery efficiency is effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas production equipment, and particularly relates to a hydraulic high-pressure pulsating pressure drive injection device and an implementation method. BACKGROUND

[0002] At present, most of the domestic oilfields have entered the middle and late stages of water injection development, and the macroscopic sweep efficiency of the oil reservoir has been close to the limit, and the exploitation work is facing severe challenges. A large amount of remaining crude oil that has not been extracted is hidden in the micro pores of the reservoir. The traditional chemical oil displacement method and the technology of increasing water injection pressure can hardly break the mechanical balance of fluid sweep in the micro pores, and are accompanied by problems such as high energy consumption, strong dependence on chemical agents, and low economic benefits. Under this background, the hydraulic pulsating pressure drive injection technology, as a low-cost technology suitable for near-water reservoir reconstruction to increase production, has been gradually researched and applied in domestic onshore oilfields in recent years. This technology has achieved remarkable results in improving difficult-to-produce oil production, increasing oil recovery, protecting oil reservoirs and ecological environment, and has advantages such as no pollution to the oil reservoir, controllable cost, simple process and convenient operation, and has broad development prospects.

[0003] In recent years, with the continuous rise of the demand for high-water-content late-stage reservoir exploitation, although the hydraulic pulsation technology is becoming mature, it can cause effects such as differential transmission, superimposed interference and inertial displacement in the reservoir, and provides a new idea for the development of high-water-content reservoirs, but there are still some limitations in the research of downhole hydraulic pulsation control devices.

[0004] The invention patent with the patent number CN102900406A can realize downhole pressure pulse oil well stimulation, but the pulsation is realized by pressure reduction, which has high energy consumption; at the same time, the pipe string needs to be lowered into the cable connected wellhead controller, which increases the risk and complexity of water injection operation.

[0005] The invention patent with the patent number CN219299263U can realize small-displacement mechanical rotary pulsating water flow through intermittent shielding of the impeller, has a simple structure, is compatible with conventional tubing, but the impeller gap is easy to be blocked by sand, the low-displacement pulsation is weak, there is no anti-sulfur design, and the risk of blade fracture is high in a corrosive environment.

[0006] The invention patent with the patent number CN116696298A can realize energy-gathering water shock wave intensification stimulation by gas bag energy storage type ground energy-gathering pulsation, the pulsation amplitude is large, the oil-water interface balance can be broken, and the sweep efficiency can be improved. However, it depends on the ground high-pressure pump system, the energy conversion efficiency is low; and the gas bag is easy to age due to repeated nitrogen charging and discharging, and the system response is delayed.

[0007] The invention patent with patent number CN113027397A can achieve hydraulic pulsation-assisted nitrogen-chemical flooding through a three-stage composite oil displacement method of gas-chemical-pulse. It can improve the recovery rate through viscosity reduction and pulsation synergy, and the integrated device reduces the surface pipeline. However, due to the uncontrollable chemical reaction of the formation fluid, there is a risk of viscosity reducer compatibility, and the valve has a high failure rate due to frequent switching.

[0008] The patent publication number CN207177869U describes a downhole low-frequency hydraulic pulsation generator for oil and gas well hydraulic fracturing. Its main working mechanism is based on a fluid pressure differential-spring reset mechanism to generate low-frequency hydraulic pulsations. However, the amplitude of this technology is entirely dependent on the drilling flow rate, making it unable to continuously and stably provide a dynamic response to the reservoir's demands. Furthermore, it lacks effective improvement and protection measures against factors affecting the equipment, such as sand production at the well bottom, sulfide corrosion, and metal fatigue. Summary of the Invention

[0009] In view of the existing technical problems, the present invention proposes a hydraulic high-pressure pulsating pressure-driven injection device and implementation method, aiming to overcome the existing problems in the above-mentioned technology.

[0010] To achieve the above objectives, this application provides the following technical solution: A hydraulic high-pressure pulsating injection device includes a one-way ball valve, a piston, an energy storage cylinder, an upper limit block, a nozzle, a lower limit block, a packer, and an energy storage spring. The upper and lower limit blocks are arranged from top to bottom inside an oil pipe. The one-way ball valve is located between the upper and lower limit blocks. A nozzle is provided on the side wall of the oil pipe above the lower limit block. The one-way ball valve is adapted to slide up and down along the oil pipe. When the one-way ball valve contacts the lower limit block, it covers the nozzle. A packer is provided between the oil pipe and the casing, and the packer is located below the lower limit block. A piston and an energy storage spring are arranged sequentially inside the oil pipe below the lower limit block. An energy storage cylinder is provided between the oil pipe and the casing, and the energy storage cylinder is located below the packer.

[0011] Optionally, the one-way ball valve has a fluid flow channel in the middle and a valve ball inside. Under the action of gravity and downward pressure, the valve ball opens the fluid flow channel, and under the action of upward pressure, the valve ball closes the fluid flow channel.

[0012] Optionally, the energy storage cylinder includes an inner cylinder and an outer cylinder, with multiple radial springs provided between the inner and outer cylinders, allowing the energy storage cylinder to expand and contract radially.

[0013] Optionally, the maximum expansion outer diameter of the energy storage cylinder shall not exceed the inner diameter of the sleeve.

[0014] Optionally, the piston may be made of iron.

[0015] Optionally, the diameter of the piston is adapted to the inner diameter of the oil pipe.

[0016] A method for implementing the hydraulic high-pressure pulsating pressure-driven injection device as described in any of the preceding claims includes the following steps: S1. Inject fluid into the oil pipe to open the one-way ball valve. At the same time, the one-way ball valve moves down to the lower limit block under its own gravity and the pressure of the liquid column. Meanwhile, the nozzle closes and the piston moves down. The gravitational potential energy and pressure energy of the fluid are converted into the elastic potential energy of the energy storage spring compression and the energy storage cylinder expansion. The fluid stores energy in the lower part of the device to realize the downstroke of the device. S2. When the device reaches its own energy storage capacity, the injection of fluid into the oil pipe is stopped. Under the pressure energy released by the energy storage fluid in the lower part, the valve ball closes the one-way ball valve. At the same time, the one-way ball valve moves up to the position of the upper limit block, the nozzle opens without obstruction, the piston moves up, the energy storage spring extends, the energy storage cylinder contracts, and the fluid stored in the lower part releases its own energy under the action of the piston, realizing the upstroke of the device. S3. When the nozzle is opened, the piston squeezes the fluid in the oil pipe under the combined action of the energy storage spring and the energy storage cylinder. After the fluid flows through the nozzle, it acts on the reservoir together with the fluid in the annulus of the oil casing, causing the rock skeleton to be displaced and disturbed, thus increasing its vibration energy. S4. As fluid is injected into the oil pipe again to store energy, the device cycles again, achieving high-pressure pulsed fluid injection.

[0017] In summary, the technical effects and advantages of this invention are as follows: 1. This invention is a downhole hydraulic high-pressure pulsation generator, which has good performance, simple structure, convenient use, and is environmentally friendly. All components are mechanical, resulting in a low failure rate. It can easily and effectively perform downhole hydraulic pulsation operations, improve water drive sweep efficiency, promote oil-water interface migration within the microporous structure, and effectively increase oil recovery. 2. When using the device to modify injection wells, the operation is simple. The device only needs to be lowered into the well once to form periodic high-pressure pulse water injection to the target layer, which greatly reduces the input of manpower and material resources. 3. Compared with traditional hydraulic impact wellhead high-pressure energy storage operations, this device can be completed in the well, reducing the operating costs of surface equipment, with low energy loss rate and stable and reliable pressure control; 4. This device can be used in oil wells, water wells, etc., with a wide range of applications and broad prospects. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a hydraulic high-pressure pulsating pressure-driven injection device in one embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the working principle of the hydraulic high-pressure pulsating pressure-driven injection device in the initial stage of fluid injection according to an embodiment of the present invention. Figure 3 This is a schematic diagram illustrating the working principle of the hydraulic high-pressure pulsating pressure-driven injection device reaching the downstroke in one embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the working principle of the hydraulic high-pressure pulsating pressure-driven injection device reaching the top stroke in one embodiment of the present invention; Figure 5 This is a front view of the energy storage cylinder in one embodiment of the present invention; Figure 6 This is a top view of the internal structure of the energy storage cylinder in one embodiment of the present invention; Figure 7 This is a schematic diagram showing the pressure change of the water injection well during water injection construction in one embodiment of the present invention.

[0020] Among them, 1. One-way ball valve; 2. Piston; 3. Energy storage cylinder; 31. Inner cylinder; 32. Outer cylinder; 33. Spring; 4. Upper limit block; 5. Nozzle; 6. Lower limit block; 7. Packer; 8. Energy storage spring. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0023] To address the inherent problems of traditional chemical flooding and increased water injection pressure in the development of high water-cut oil reservoirs, which fail to fundamentally overcome the mechanical balance of microscopic sweep efficiency and suffer from low energy conversion efficiency, sluggish dynamic response, high tubing vibration damage rate, and pressure fluctuation instability in existing pulsation devices, this invention designs a hydraulic high-pressure pulsation injection device. This device regulates the reservoir seepage field through periodic high-pressure fluctuations, aiming to improve the inefficient displacement and reservoir damage caused by traditional steady-state water injection. Simultaneously, it ensures stable energy conversion and transport, reduces tubing vibration damage, and achieves continuous conversion of hydraulic kinetic energy and pressure energy, enabling unblocking, permeability enhancement, fracturing, and large-scale enhanced waterflooding. This device innovatively constructs a dynamic hydraulic-pressure conversion mechanism, effectively overcoming the disadvantages of traditional pulsation generating devices, and is expected to significantly improve the adaptability of hydraulic pulsation in the development of high water-cut oil reservoirs.

[0024] This embodiment proposes a hydraulic high-pressure pulsating pressure-driven injection device, such as... Figures 1-7 As shown, the system includes a one-way ball valve 1, a piston 2, an energy storage cylinder 3, an upper limit block 4, a nozzle 5, a lower limit block 6, a packer 7, and an energy storage spring 8. The upper limit block 4 and the lower limit block 6 are arranged from top to bottom inside the oil pipe. The one-way ball valve 1 is located between the upper limit block 4 and the lower limit block 6. The nozzle 5 is located on the side wall of the oil pipe above the lower limit block 6. The one-way ball valve 1 is adapted to slide up and down along the oil pipe. When the one-way ball valve 1 contacts the lower limit block 6, the one-way ball valve 1 covers the nozzle 5. A packer 7 is provided between the oil pipe and the casing. The packer 7 is located below the lower limit block 6. The piston 2 and the energy storage spring 8 are arranged sequentially inside the oil pipe below the lower limit block 6. The energy storage cylinder 3 is provided between the oil pipe and the casing. The energy storage cylinder 3 is located below the packer 7.

[0025] Optionally, the one-way ball valve 1 has a liquid flow channel in the middle and a valve ball inside. Under the action of gravity and downward pressure, the valve ball opens the liquid flow channel, and under the action of upward pressure, the valve ball closes the liquid flow channel.

[0026] Optionally, the energy storage cylinder 3 includes an inner cylinder 31 and an outer cylinder 32, with multiple radial springs 33 between the inner cylinder 31 and the outer cylinder 32, allowing the energy storage cylinder 3 to expand and contract radially. The energy storage cylinder 3 has a double-layer structure and can be made of elastic materials such as rubber; while ensuring effective energy storage of the rubber cylinder, it also provides a certain degree of support. The diameter of the energy storage cylinder 3 is determined according to the inner diameter of the well casing, ensuring that its maximum expansion outer diameter does not exceed the inner diameter of the casing.

[0027] Optionally, the piston 2 may be made of iron.

[0028] Optionally, the diameter of the piston 2 is adapted to the inner diameter of the oil pipe to ensure a certain degree of sealing.

[0029] Optionally, the energy storage spring 8 can be made of high-carbon spring steel, which has strong elasticity and strong stress resistance.

[0030] Further preferably, the average helix diameter of the energy storage spring 8 is 50mm, the wire diameter is 7mm, and the elastic modulus of the energy storage spring 8 is selected to be 12000N / m. The spring's physical properties can be further selected based on the actual geological conditions and sleeve space limitations to ensure successful elastic energy storage.

[0031] This embodiment also proposes an implementation method for the hydraulic high-pressure pulsating pressure-driven injection device described in any of the foregoing items. The device uses a packer 7 to inject water at constant pressure into the target layer from the annulus of the oil jacket, and uses an intermediate oil pipe to perform elastic energy storage for the device. A specially designed energy storage spring 8 and an energy storage cylinder 3 are installed at the bottom of the device to form an energy storage structure.

[0032] Specifically, the following steps are included: S1. As Figure 2 and 3 As shown, fluid is injected into the oil pipe, causing the one-way ball valve 1 to open. At the same time, the one-way ball valve 1 moves down to the lower limit block 6 under its own gravity and the pressure of the liquid column. Meanwhile, the nozzle 5 closes, the piston 2 moves down, and the gravitational potential energy and pressure energy of the fluid are converted into elastic potential energy by the compression of the energy storage spring 8 and the expansion of the energy storage cylinder 3. The fluid stores energy in the lower part of the device to achieve the downstroke of the device. S2. For example Figure 4 As shown, when the device reaches its own energy storage capacity, the injection of fluid into the oil pipe stops. Under the pressure energy released by the energy storage fluid in the lower part, the valve ball blocks the liquid flow channel, forcing the one-way ball valve 1 to close. At the same time, the one-way ball valve 1 moves up to the position of the upper limit block 4, the nozzle 5 opens without obstruction, the piston 2 moves up, the energy storage spring 8 extends, the energy storage cylinder 3 contracts, and the fluid stored in the lower part releases its own energy under the action of the piston 2, realizing the upstroke of the device. S3. For example Figure 4 As shown, when the nozzle 5 is opened, the piston 2 squeezes the fluid in the oil pipe under the combined action of the energy storage spring 8 and the energy storage cylinder 3. After the fluid flows through the nozzle 5, it acts on the reservoir together with the fluid in the oil casing annulus, causing the rock skeleton to be displaced and disturbed, thus increasing its vibration energy. S4. As fluid is injected into the oil pipe again to store energy, the device cycles again, achieving high-pressure pulsed fluid injection.

[0033] This device uses packer 7 to inject water at constant pressure into the target layer from the annulus of the oil casing. It uses intermediate oil pipe to store elastic energy. Under the action of liquid column pressure and its own gravity, one-way ball valve 1 moves down to the lower limit block 6 and blocks nozzle 5. Fluid in the oil pipe enters the oil pipe through the liquid flow channel in the middle of one-way ball valve 1, driving piston 2 to move downward. The gravitational potential energy and injection pressure of the fluid are converted into elastic potential energy of energy storage spring 8 and energy storage cylinder 3. After reaching a certain energy, the injection of fluid into the oil pipe stops, completing the downstroke energy storage process, and the oil pipe is filled with fluid. Then, the energy storage spring 8 and the energy storage cylinder 3 force the piston 2 upward. The pressure inside the cylinder exceeds the pressure of the tubing fluid column, and the valve ball, under the action of the pressure difference, blocks the water inlet at its upper part, preventing fluid from flowing back into the wellbore. This causes the one-way ball valve 1 to move to the upper limit block 4. At the same time, since the nozzle 5 is not blocked, the elastic potential energy stored in the device is converted into the pressure energy of the fluid, which, together with the fluid in the annulus, acts on the target reservoir. After completing the upstroke release process, a large volume of fluid is injected again to store energy, and this process is repeated. This achieves high-pressure pulsating water injection into the target layer for a certain period of time, causing the pulsating wave to propagate inside the reservoir, generating misalignment disturbance, improving sweep efficiency, and thus further improving the oil recovery rate. The device of this invention has a simple structure, making downhole pulsating impact simple and effective, and can greatly improve the water drive effect.

[0034] In summary, the technical effects and advantages of this invention are as follows: 1. This invention is a downhole hydraulic high-pressure pulsation generator, which has good performance, simple structure, convenient use, and is environmentally friendly. All components are mechanical, resulting in a low failure rate. It can easily and effectively perform downhole hydraulic pulsation operations, improve water drive sweep efficiency, promote oil-water interface migration within the microporous structure, and effectively increase oil recovery. 2. When using the device to modify injection wells, the operation is simple. The device only needs to be lowered into the well once to form periodic high-pressure pulse water injection to the target layer, which greatly reduces the input of manpower and material resources. 3. Compared with traditional hydraulic impact wellhead high-pressure energy storage operations, this device can be completed in the well, reducing the operating costs of surface equipment, with low energy loss rate and stable and reliable pressure control; 4. This device can be used in oil wells, water wells, etc., with a wide range of applications and broad prospects.

[0035] The method of using this device is described using the target well in Table 1 as an example; the injected fluid can be water.

[0036] Table 1. Basic data of the target well The fracturing section of this well extends from 1986.1m to 2087.4m, with the wellbore reaching a depth of 2184.96m. To achieve the effect of hydraulically pulsating high-pressure water injection, a high-pressure pumping device can be lowered to a depth of 2084m.

[0037] Preferably, piston 2 is made of iron block with a diameter of 100mm and a length of 5m.

[0038] Preferably, the steel material of the energy storage spring 8 is carbon spring steel, which has strong elasticity and strong stress resistance. The average helix diameter of the energy storage spring 8 is 50mm, the wire diameter is 7mm, and the elastic coefficient k of the energy storage spring 8 can be selected as 12000N / m.

[0039] Preferably, the energy storage cylinder 3 is a double-layered rubber cylinder with an attached spring, with 30 cylinders in total, each with a diameter of 120mm and a length of 2m, and is placed sequentially on the oil pipe.

[0040] During the downward stroke of piston 2, the gravitational potential energy of piston 2 and the pressure energy of the injected water are converted into the elastic potential energy of the energy storage spring 8 and the energy storage cylinder 3. During the upward stroke of piston 2, the energy release process is the kinetic energy of water and the gravitational potential energy of piston 2. Then, the high-pressure flow rate through nozzle 5 and the annular constant-pressure fluid act together on the target layer to perform pulse oscillation. The feasibility is explained by calculation below.

[0041] Assuming the energy storage cylinder has an elastic modulus E = 5 MPa and a Poisson's ratio... =0.45, calculated as follows: Calculation of volume change of the energy storage cylinder: Original diameter: 100mm, radius m; Diameter after expansion: 120mm, radius m Volume change of the energy storage cylinder: m 3 Where h represents the height of all energy storage cylinders; Calculation of the bulk modulus of the energy storage cylinder: MPa; Elastic potential energy of the energy storage cylinder calculate: Where V1 represents the original volume of the energy storage cylinder; Assuming the stretching range Δx of the energy storage spring is 50m and the spring constant k is chosen to be 12000N / m, the elastic potential energy generated by the energy storage spring... for: Total energy E produced 总 : E 总 =E² + U = 15760452J Energy loss is calculated at 20%, and the device can store a liquid column height H of 80m (without considering energy storage cylinder deformation). V=H×π×r1×r1=80×π×0.05×0.05=0.6283m 3 Even after energy loss, the fluid pressure inside the wellbore can still reach [a certain level]. The generated pressure is greater than that of the constant-pressure fluid in the annulus (wherein, the constant-pressure fluid refers to the pressure-driven fluid in existing technology), thus enabling high-pressure pulsed circulation water injection downhole. The casing has perforations corresponding to nozzle 5, through which fluid can be injected into the target formation. This is accomplished through a perforation process, both of which are existing technologies. This device utilizes the annulus to inject fluid into the target formation at constant pressure, while simultaneously injecting a large volume of fluid (e.g., water) into the tubing. The elastic potential energy stored in the device is converted into the pressure energy of the fluid. Pulsating waves propagate within the reservoir, generating displacement disturbances, improving sweep efficiency, expanding the sweep range, and further enhancing porosity and recovery rates. After the energy is released, a large volume of fluid (e.g., water) is injected again for energy storage, and this process is repeated. This achieves high-pressure pulsed water injection into the target formation for a certain period. The device of this invention has a simple structure, making downhole pulsed impact simple and effective, and can greatly improve water drive performance.

[0042] Although preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not limiting. Those skilled in the art can make many specific modifications under the guidance of the present invention without departing from the spirit of the invention and the scope of protection of the claims, and these modifications all fall within the scope of protection of the present invention.

Claims

1. A hydraulic high pressure pulsating pressure drive injection device, characterized in that, The device comprises a one-way ball valve, a piston, an energy storage cylinder, an upper limit block, a nozzle, a lower limit block, a packer and an energy storage spring, the upper limit block and the lower limit block are arranged in the oil pipe from top to bottom, the one-way ball valve is arranged between the upper limit block and the lower limit block, the nozzle is arranged on the oil pipe sidewall above the lower limit block, the one-way ball valve is adapted to slide up and down along the oil pipe, when the one-way ball valve contacts the lower limit block, the one-way ball valve covers the nozzle, the packer is arranged between the oil pipe and the casing, the packer is arranged below the lower limit block, the piston and the energy storage spring are arranged in the oil pipe below the lower limit block in sequence, the energy storage cylinder is arranged between the oil pipe and the casing, and the energy storage cylinder is arranged below the packer.

2. The hydraulic high pressure pulsating pressure drive injection device according to claim 1, characterized in that The middle part of the one-way ball valve is provided with a liquid flow channel, and a valve ball is arranged in the one-way ball valve, under the action of gravity and downward pressure, the valve ball opens the liquid flow channel, and under the action of upward pressure, the valve ball closes the liquid flow channel.

3. The hydraulic high pressure pulsating pressure drive injection device of claim 1, wherein, The energy storage cylinder comprises an inner cylinder body and an outer cylinder body, a plurality of radial springs are arranged between the inner cylinder body and the outer cylinder body, and the energy storage cylinder can expand and contract radially.

4. The hydraulic high pressure pulsating pressure drive injection device of claim 2, wherein, The maximum expansion outer diameter of the energy storage cylinder does not exceed the inner diameter of the sleeve.

5. The hydraulic high pressure pulsating pressure drive injection device of claim 1, wherein, The piston is made of iron.

6. The hydraulic high pressure pulsating pressure drive injection device of claim 1, wherein, The diameter of the piston is matched with the inner diameter of the oil pipe.

7. A method for implementing the hydraulic high pressure pulsating pressure injection device according to any one of claims 1-6, characterized in that, The device comprises the following steps: S1. Injecting fluid into the oil pipe to open the one-way ball valve, while the one-way ball valve is lowered to the lower limit block under the action of its own gravity and the liquid column pressure, the nozzle is closed, the piston is lowered, the gravitational potential energy and the pressure energy of the fluid are converted into the elastic potential energy of the compression of the energy storage spring and the expansion of the energy storage cylinder, the fluid is stored in the lower part of the device, and the downstroke of the device is realized; S2. When the device reaches its energy storage capacity, stop injecting fluid into the oil pipe, the one-way ball valve is closed under the pressure energy released by the lower part of the energy storage fluid, the one-way ball valve is raised to the position of the upper limit block, the nozzle is not blocked and opened, the piston is raised, the energy storage spring is stretched, the energy storage cylinder is contracted, and the lower part of the stored fluid releases its energy under the action of the piston, and the upstroke of the device is realized; S3. When the nozzle is opened, the piston extrudes the fluid in the oil pipe under the joint action of the energy storage spring and the energy storage cylinder, the fluid flows through the nozzle and acts on the reservoir together with the fluid in the oil casing annulus, so as to make the rock framework produce dislocation disturbance and vibration energy increase; S4. With the energy storage of injecting fluid into the oil pipe again, the device is recycled again, and high-pressure pulsating fluid injection is realized.

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