A jet pump type hydraulic impactor and method for improved performance

Abstract

The application relates to a jet-suction type hydraulic impactor and method capable of improving working performance, which comprises a connecting section, a jet-suction section, an impact section and an external shell; the connecting section is an upper joint used for being connected with an upper drill rod; the jet-suction section is arranged below the upper joint and comprises a nozzle, a spray receiver and a movable valve; the impact section comprises an impact anvil and a drill bit assembly; the external shell comprises a shell pipe; the movable valve is used for forming a suction effect and a water hammer effect with high-pressure driving liquid, reciprocally moves relative to the shell pipe, drives a piston hammer to periodically hit the anvil, and transmits impact work received by the anvil to the drill bit assembly connected with the anvil to impact and break rocks. The application comprises an execution mechanism with fixed parameters, a movable valve and a valve type structure composed of a piston hammer with an axial through hole, the working flow range of the jet-suction type hydraulic impactor is widened, the rock breaking efficiency is improved, the service life of the hydraulic impactor is prolonged, and the working performance of the hydraulic impactor is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas field development, in particular to the technical field of drilling, and specifically to a jet suction type hydraulic impactor and method capable of improving working performance. BACKGROUND

[0002] Currently, the research on hydraulic impactors worldwide has reached a very mature field, and the most effective hydraulic impactor in practical application is a jet suction type hydraulic impactor. However, the jet suction type hydraulic impactor is the least researched and applied hydraulic impactor. It is installed on a rotary drilling tool as an auxiliary rock breaking tool and is widely used in the fields of drilling and well drilling. It is beneficial to improve drilling efficiency, improve core recovery rate, prevent broken rock layer from blocking the drilling tool, improve the service life of the drill bit, and control the hole deviation. It is the pressure difference generated by the jet suction negative pressure suction that makes the movable valve reach the upper limit position before the hammer, and then the hammer rod goes up and collides with the movable valve to close the water passage, thereby generating a huge water hammer pressure in the upper cavity of the impactor. The water hammer pressure acts on the upper end surface of the hammer rod and the movable valve, generating a downward thrust to push the hammer rod and the movable valve downward. The movable valve stops moving under the action of the lower limit device, and the hammer rod continues to move downward for a free stroke under the action of the inertial force, and then hits the anvil. This process is repeated to perform impact work.

[0003] From the above working principle, in order to achieve the best performance of the hydraulic impactor, two conditions must be met: first, to ensure that there is no large friction contact, water flow resistance and other energy losses before the piston hammer collides with the impact anvil, and the pressure of the high-pressure liquid flow is used to the greatest extent; second, to ensure that the piston hammer and the movable valve do not have rigid collision during normal operation, which leads to energy loss and early disengagement, resulting in early return. However, the current jet suction type hydraulic impactor has the problem of too large suction unit, non-fixed structure parameters, unstable suction performance, and large differences in working pressure and starting flow due to machining precision, changes in flushing fluid flow, sand content and other reasons in actual application, which leads to unstable impact frequency, reduced impact work, low water energy utilization rate, and decreased impactor performance. SUMMARY

[0004] The present application aims to improve the reliability of the jet suction type hydraulic impactor, solve the technical deficiencies of unstable working pressure, non-fixed structure parameters, large starting flow, low energy utilization rate, and unstable performance of the movable valve and hammer in the existing jet suction type hydraulic impactor technology, thereby ensuring stable rock breaking of the drill bit, improving the rock breaking energy and efficiency of the drill bit, reducing the risk of damage to the hammer valve due to rigid collision, and improving the service life of the impactor and the stability of the entire drilling system.

[0005] To achieve the above purpose, the technical solution adopted by the present application is as follows:

[0006] The jet suction type hydraulic impactor can improve working performance, and its structure comprises an upper joint, a sealing ring, a nozzle, a supporting device, a limiting guide sleeve, a valve, a piston hammer, a shell pipe, an impact anvil, a guide bushing, a stop ring, a drill bit sleeve and a drill bit.

[0007] Further, the nozzle is installed in the central hole of the upper joint, the lower end of the outer side of the nozzle is provided with a limiting step, the nozzle is fixed by the limiting step of the upper end of the supporting device extending into the central hole; the supporting device is fixed by the limiting step of the lower end of the shell pipe; the limiting guide sleeve is installed in the groove of the middle section of the shell pipe and is limited up and down by the groove; the limiting guide sleeve is a left-right symmetrical split type, and is installed by staggering to ensure a gap of 1-2 mm between the installation outer diameter and the shell pipe and a gap of 2-3 mm between the inner diameter of the lower end and the upper end of the piston hammer. Further, the valve type structure has an unequal diameter shape with small ends and a large middle, the valve has a central water passage hole, the bottom surface is a convex cone type with a 120° taper angle, the lower section side surface is provided with a lateral drainage hole, the high pressure liquid flowing into the valve flows to the lateral drainage hole at the bottom and does not consume too much energy; the upper end of the valve is in sliding sealing cooperation with the inner hole of the upper cylinder sleeve; the valve slides up and down along the inner hole of the upper cylinder sleeve, the middle section of the valve is a smooth cylindrical surface, the radial circular runout of the large diameter is 0.01-0.03 mm, the surface roughness Ra value is 0.63-0.16 μm, and the bottom of the valve is rounded with a 5 mm radius; the upper part of the valve is processed with a ring groove inner chamfer of 25°, so that the upper end of the valve cannot be moved up due to high pressure, and the gathering property of the driving liquid is ensured, the ring groove part is installed in the limiting pad, the outer diameter of the groove hole and the ring groove small diameter of the valve has a gap cooperation of 1.0 mm, and the valve can freely move up and down in the limiting pad; the up and down movement of the valve is limited and controlled by the shoulder and the limiting pad, the shoulder protrudes outward by 10 mm and is rounded with a 5 mm radius;

[0008] Further, the piston hammer has an axial through hole structure, the inner wall through hole diameters are different, the upper part of the piston hammer and the middle part of the valve have a gap cooperation of 0.01-0.02 mm, the high pressure liquid flow cannot be sprayed from the top of the piston hammer; the lower central water hole of the smallest diameter of the piston hammer is smaller than the outer diameter of the lower end of the valve; before starting, the high pressure liquid flow flows into the annular cavity through the lateral drainage hole at the lower end of the valve and flows into the lower central water hole of the piston hammer through the gap;

[0009] Furthermore, the valve has an unequal outer diameter, with a 2-3mm gap between the upper outer diameter and the outer casing. The valve slides up and down along the lower outer diameter of the nozzle. The middle section of the valve is a smooth cylindrical surface, with a sliding seal between the small diameter section and the limiting guide sleeve. The radial runout tolerance at the large diameter section is 0.01-0.03mm, and the surface roughness Ra value is 0.63-0.16μm. The shoulder of the valve protrudes outward by 10mm and has a 5mm rounded corner. The valve has a side drain hole, and the bottom surface is a closed concave structure, which reduces the speed of the high-pressure liquid flow and allows it to flow into the annular cavity from the side drain hole at the lower end. Then, it flows into the four lifting grooves at the bottom of the piston hammer from the lower central water hole. The hammer groove generates a throttling and pressurizing effect, and the cavity is subjected to huge upward pressure. Under the action of pressure, the piston hammer quickly rises to the position where the central step of the piston hammer just touches the bottom of the valve and stops. Before the piston hammer rises, the valve moves upward due to the suction effect until it blocks the water passage. The upper outer circle of the valve slides up and down with the lower cylindrical section of the nozzle. The inner cavity of the valve is a smooth cylindrical surface with a radial runout tolerance of 0.01 to 0.03 mm and a surface roughness Ra value of 0.63 to 0.16 μm. The radius of the concave circle at the bottom of the valve is 25 mm, and the diameter of the side drain hole is 40 mm. The upper and lower movement limit distance of the valve is controlled by the nozzle and the limiting guide sleeve.

[0010] Furthermore, the nozzle has an inner cavity in the middle, and its lower end forms an outer cavity with the upper end of the valve, which is connected by six water passages. High-pressure liquid flows into the nozzle from the central hole of the upper connector and is sprayed to form a high-speed jet. When the high-speed jet passes through the inner cavity, there is a velocity difference with the surrounding liquid, which reduces the pressure in the inner cavity. A pressure difference is formed between the liquid in the inner cavity and the liquid in the outer cavity. Under the action of the pressure difference, the liquid in the outer cavity is drawn into the inner cavity space through the water passages. It is carried by the high-speed jet flowing out of the nozzle through the central channel of the valve, through the lower central water hole of the piston hammer, and through the central water hole of the impact anvil to enter the drill bit, assisting the drill bit in breaking rock. The liquid flow carries debris and returns upward from the outer ring space of the impactor.

[0011] Furthermore, an annular cavity is formed between the piston hammer and the outer casing tube, creating an external drainage channel to ensure no contact between the piston hammer and the outer casing tube, thus reducing frictional loss. The central hole of the impact anvil is connected to the lifting groove of the piston hammer, creating a passage from a high-pressure area to a low-pressure area. After the piston hammer is lifted, based on thorough design calculations, the diameter of the lifting groove is designed to be 10mm, achieving a maximum flow rate of 2.26m³ / h. 3 / h, the lifting groove has the effect of throttling and pressurizing, causing the piston hammer to move upward at varying speeds; when the piston hammer moves upward at a speed of 0m / s, it is the maximum displacement of the piston hammer. The lower sleeve-shaped structure separates from the impact anvil, allowing a large amount of liquid in the central fluid channel of the piston hammer to flow into the side channel and then into the drill bit through the gap and flow to the external space. This reduces the pressure inside the cavity in a short time. Only a small amount of liquid exists, which will not weaken the impact force of the piston hammer on the impact anvil, and the depressurization process will not affect the impact process of the piston hammer.

[0012] As a preferred implementation, in the free state before startup, the valve and piston hammer of the jet-suction hydraulic impactor are both in their lowest positions. The "I"-shaped structure of the valve is limited by the upper end face of the limiting guide sleeve, leaving an annular cavity. There is a 10mm gap between the lower end face of the valve and the step. At this time, the central water passage of the hydraulic impactor is in the open state, and the fluid can pass through. When there is high-pressure fluid flow, the high-speed jet generated by the nozzle forms a suction effect in the inner and outer cavities, causing the valve to move upward to the water passage and be blocked. The piston hammer begins to move upward to the step and contact the valve to block the central fluid flow channel. The high-pressure fluid flow in the inner cavity and valve is obstructed and a water hammer effect is generated, which pushes the valve and piston hammer downward to strike the impact anvil and do work. The central fluid flow channel opens again, and the blocked water passage opens at the same time, so that the pressure in the outer cavity is restored again. The valve and piston hammer begin a new round of upward return motion. This cycle repeats continuously. The piston hammer continuously strikes the impact anvil to generate impact energy, which is transmitted to the drill bit to break the rock.

[0013] In a preferred embodiment, the impact anvil has a central drainage hole, and the drill bit is located below the impact anvil. The impact anvil transmits the impact force to the upper spline-free portion of the drill bit. The drill bit has a head and a shank, which consists of a splined portion and a spline-free portion. The spline-free portion has a guide bushing, and a stop is sandwiched between the guide bushing and the sleeve to prevent the drill bit from falling off. The stop ring is axially split for easy installation. The drill bit can move axially between its rear and front ends, but the axial movement distance is limited, and it cannot rotate relative to the outer casing. The drill bit has a central channel from its shank to the front end for discharging the driving fluid to assist in rock breaking. All parts of the drill bit are easy to assemble, have low requirements for axial tolerance, and any increased tolerance is absorbed by axial elastic compression. All parts can easily slide within the impactor's outer casing, making the hydraulic impactor easy to disassemble.

[0014] As a preferred embodiment, the lower section of the piston hammer is a sleeve structure, which fits with the upper section of the impact anvil with a 2mm outer diameter clearance, forming a relatively sealed cavity at the four hammer lifting grooves. This structure ensures that the position of the piston hammer striking the impact anvil remains unchanged each time the piston hammer strikes it. The lower section of the piston hammer has a vent hole that allows the high-pressure fluid from the central fluid flow channel to be rapidly released into the drain hole at the lower end of the impact anvil when the piston hammer moves upward to zero velocity, and then enters the central water hole. This reduces the internal pressure in a short time, ensuring that only a small amount of fluid remains, which does not weaken the impact force of the piston hammer. The pressure relief process does not affect the downward impact process of the piston hammer.

[0015] Compared with existing hydraulic impactors, the features and advantages of this invention are:

[0016] This invention provides a jet-suction type hydraulic impactor that can improve working performance.

[0017] 1. The present invention adopts a fixed injection unit structure consisting of a nozzle, a nozzle holder, and a valve. The structure is simple, the injection parameters are stable, the energy output of the hammer is large when the flow rate is large, and the frequency and impact energy are also stable when the flow rate is stable, resulting in high energy utilization.

[0018] 2. This invention adopts a separate piston hammer and valve structure, which can achieve no rigid collision between the hammer and valve structure during the rock-breaking drilling process, thereby eliminating the possibility that the upward impact force is greater than the downward impact force; the throttle orifice design is eliminated, the piston hammer has a larger mass, which allows the piston hammer to obtain a high downward impact velocity during the stroke, improving energy utilization, thereby ensuring that the hydraulic impactor drill bit has sufficient impact power, enabling stable and efficient rock breaking, improving drill bit life and the stability of the entire drilling system.

[0019] 3. This invention has no easily damaged parts such as springs, has stable quality, is safe downhole, and does not experience pressure jamming under any circumstances. Its performance parameters (impact energy, impact frequency) have a wide adjustable range, and it is more effective in accelerating and improving efficiency in hard formations. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the device of the present invention in its initial state;

[0021] Figure 2 This is a schematic diagram of the drill bit structure of the present invention;

[0022] Figure 3 For the present invention Figure 1 Top view of section AA;

[0023] In the diagram: 1. Upper connector, 2. Sealing ring, 3. Nozzle, 4. Spray receiver, 5. Limiting guide sleeve, 6. Valve, 7. Piston hammer, 8. Outer tube, 9. Impact anvil, 10. Clearance, 11. Guide bushing, 12. Spline-free part of drill bit, 13. Stop ring, 14. Spline, 15. Sleeve, 16. Drill bit, 17. Hammer lifting groove, 18. Outer drainage channel, 19. Piston hammer central fluid flow channel, 20. Shoulder, 21. Lateral drainage hole, 22. Annular cavity, 23. Outer cavity, 24. Water passage hole, 25. Inner cavity, 26. Central hole. Detailed Implementation

[0024] The present invention will be further described below with reference to embodiments. It should be noted that, in this document, terms such as "upper" and "lower" are used merely for the convenience of describing the drawings and are not intended to limit the direction in actual use, nor do they necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0025] The following describes some embodiments of the ejector-type hydraulic impactor with improved working performance, in conjunction with the accompanying drawings:

[0026] This invention primarily addresses the aforementioned injection-suction type hydraulic impactor, which can improve working performance, such as... Figure 1 As shown, the structure of the jet-suction hydraulic impactor includes an upper connector 1, a sealing ring 2, a nozzle 3, a jet receiver 4, a limiting guide sleeve 5, a valve 6, a piston hammer 7, an outer shell tube 8, an impact anvil 9, a guide bushing 11, a stop ring 13, a drill bit sleeve 15, and a drill bit 16. The above components are installed inside the outer shell tube 8 of the hydraulic impactor. The upper end of the outer shell tube 8 is rigidly connected to the upper connector 1 by a thread, and the connection is sealed by a sealing ring 2. The valve 6 is used to interact with the high-pressure driving fluid and reciprocates relative to the outer shell tube 8. The opening and closing of the central water passage drives the piston hammer 7 to periodically strike the impact anvil 9. The impact energy received by the impact anvil 9 is transmitted to the drill bit 16 in contact with it to break rocks by impact.

[0027] The nozzle 3 is installed in the center hole 26 of the upper connector 1. A limiting step is provided at the lower outer side of the nozzle 3. The nozzle 3 is limited and fixed by the limiting step at the upper end of the nozzle holder 4 that extends into the center hole 26. The nozzle holder 4 is limited and fixed by the limiting step at its lower end and the outer shell tube 8. The limiting guide sleeve 5 is installed in the groove in the middle section of the outer shell tube 8. The groove limits the upper and lower movement. The limiting guide sleeve 5 is a symmetrical and separable type. During installation, it is installed in an alternating manner. In order to ensure that there is a gap of 1-2mm between the outer diameter of the installation and the outer shell tube 8, there is a gap of 2-3mm between the lower inner diameter and the upper end of the piston hammer 7.

[0028] The piston hammer 7 has an axial through-hole structure with different diameters of the through-holes in its inner wall. The upper part of the piston hammer 7 and the middle part of the valve 6 are fitted with a clearance of 0.01-0.02mm to ensure that the high-pressure liquid flow will not spray out from the top of the piston hammer 7. The lower central water hole 19 of the piston hammer 7 with the smallest diameter is smaller than the outer diameter of the lower end of the valve 6. Before starting, the high-pressure liquid flow flows into the annular cavity 22 through the lateral drain hole 21 at the lower end of the valve 6, and flows into the lower central water hole 19 of the piston hammer 7 from the gap 20.

[0029] The valve 6 has an unequal outer diameter, with a 2-3mm gap between its upper outer diameter and the outer casing tube 8. The valve 6 slides up and down along the lower outer diameter of the nozzle 4. The middle section of the valve 6 is a smooth cylindrical surface, with a sliding seal between the small diameter section and the limiting guide sleeve 5. The radial runout tolerance at the large diameter section is 0.01-0.03mm, and the surface roughness Ra value is 0.63-0.16μm. The shoulder 20 in the middle of the valve 6 protrudes outward by 10mm and has a 5mm rounded corner. The valve 6 has a side drain hole 21, and its bottom surface is a closed concave structure, which reduces the speed of the high-pressure liquid flow and allows it to flow from the side drain hole 21 at the lower end into the annular cavity 22. Then, it flows from the lower central water hole 19 into the four hammer-lifting grooves 17 at the bottom of the piston hammer 7. 17 will generate a throttling and pressurizing effect, and the cavity will be subjected to huge upward pressure. Under the action of pressure, the piston hammer 7 will quickly move upward until the center step 20 of the piston hammer just touches the bottom of the valve 6 and stops. Before the piston hammer 7 moves upward, the valve 6 moves upward due to the suction effect until it blocks the water passage 24. The upper outer circle of the valve 6 slides up and down with the lower cylindrical section of the nozzle 4. The inner cavity of the valve 6 is a smooth cylindrical surface with a radial runout tolerance of 0.01 to 0.03 mm and a surface roughness Ra value of 0.63 to 0.16 μm. The radius of the concave circle at the bottom of the valve 6 is 25 mm, and the diameter of the side drain hole 20 is 40 mm. The limit distance of the up and down movement of the valve 6 is limited and controlled by the nozzle 4 and the limiting guide sleeve 5.

[0030] The nozzle 4 has an inner cavity 25 in the middle, and its lower end forms an outer cavity 23 with the upper end of the valve 6. It is connected by six water passages 24. High-pressure liquid flows into the nozzle 3 from the central hole 26 of the upper connector 1 and is sprayed to form a high-speed jet. When the high-speed jet passes through the inner cavity 25, there is a velocity difference with the surrounding liquid, which reduces the pressure in the inner cavity 25. A pressure difference is formed between the liquid in the inner cavity 25 and the liquid in the outer cavity 23. Under the action of the pressure difference, the liquid in the outer cavity 23 is drawn into the space of the inner cavity 25 through the water passages 24. It is carried by the high-speed jet flowing out of the nozzle 3 through the central channel of the valve 6, through the lower central water hole 19 of the piston hammer, and through the central water hole of the impact anvil 9 to enter the drill bit to assist the drill bit in breaking rock. The liquid flow carries the debris and returns upward from the outer ring space of the impactor.

[0031] The piston hammer 7 and the outer casing tube 8 form an annular cavity with an outer drainage channel 18, ensuring no contact between the piston hammer and the outer casing tube and reducing frictional loss. The central hole of the impact anvil 9 is connected to the lifting groove 17 of the piston hammer 7, creating a passage from a high-pressure area to a low-pressure area. When the piston hammer 7 is lifted, based on thorough design calculations, the diameter of the lifting groove is designed to be 10mm, achieving a maximum flow rate of 2.26m³ / h. 3 / h, the lifting groove 17 has the effect of throttling and pressurizing, causing the piston hammer to move upward at a variable speed; when the upward speed of the piston hammer 7 is 0m / s, it is the maximum displacement of the piston hammer 7. The lower sleeve-shaped structure separates from the impact anvil 9, and a large amount of liquid flow in the central liquid flow channel of the piston hammer flows into the side channel 18 and then enters the drill bit 16 through the gap 10 and flows into the external space. In a short time, the pressure in the cavity is reduced, and only a small amount of liquid flow exists, which will not weaken the impact force of the piston hammer 7 on the impact anvil 9, and the pressure relief process will not affect the impact process of the piston hammer 7.

[0032] Furthermore, in the free state before startup, the valve 6 and piston hammer 7 of the jet-suction hydraulic impactor are both in their lowest positions. The "I"-shaped structure of the valve 6 is limited by the upper end face of the limiting guide sleeve 5, leaving an annular cavity 22. There is a 10mm gap between the lower end face of the valve 6 and the step 20. At this time, the central water passage of the hydraulic impactor is in the open state, and the liquid flow can pass through. When there is high-pressure liquid flow, due to the suction effect formed by the high-speed jet generated by the nozzle in the inner and outer cavities, the valve 6 moves upward to the water passage 24 and is blocked. The piston hammer 7 begins to move upward to the step 20 and contacts the valve, blocking the central liquid flow channel. The high-pressure liquid flow in the inner cavity 25 and the valve is obstructed and a water hammer effect is generated, which pushes the valve 6 and piston hammer 7 downward to strike the impact anvil 9 to do work. The central liquid flow channel is opened again, and the valve 6 and piston hammer 7 begin a new round of upward return motion. This cycle repeats, and the piston hammer 7 continuously strikes the impact anvil 9 to generate impact energy, which is transmitted to the drill bit 16 to break the rock.

[0033] Furthermore, the impact anvil 9 has a central drainage hole, and the drill bit 16 is located below the impact anvil 9. The impact anvil 9 transmits the impact force to the upper spline-free portion 12 of the drill bit 16. The drill bit 16 has a head and a shank, which consists of a splined portion 14 and a spline-free portion 12. The spline-free portion 12 has a guide bushing 11, and a stop ring 13 is sandwiched between the guide bushing and the sleeve 15 to prevent the drill bit from falling off. The stop ring 13 is axially split for easy installation. The drill bit 16 can move axially between its rear end and front end. The axial movement distance of the drill bit is limited, and it cannot rotate relative to the outer casing tube 8. The drill bit 16 has a central channel from its shank to the front end of the drill bit for discharging the driving fluid to assist in rock breaking. All parts of the drill bit are easy to assemble, have low requirements for axial tolerance, and the increased tolerance is absorbed by axial elastic compression. All parts can easily slide within the impactor outer casing tube 8, so the hydraulic impactor is easy to disassemble.

[0034] Furthermore, the lower section of the piston hammer 7 is a sleeve structure, which is fitted with the upper section of the impact anvil 9 with a 2mm outer diameter clearance, forming a relatively sealed cavity at the four hammer lifting grooves 17. When the piston hammer 7 moves up and down, this structure can ensure that the position of the piston hammer 7 striking the impact anvil 9 remains unchanged each time. The lower section of the piston hammer has a drain hole 30, which can quickly release the high-pressure liquid flow from the piston hammer's central liquid flow channel 25 into the drain hole 31 at the lower end of the impact anvil when the piston hammer moves upward to a speed of 0, and then enter the central water hole 32; the internal cavity pressure is reduced in a short time, and only a small amount of liquid flow exists, which will not weaken the impact force of the piston hammer 7. The pressure relief process will not affect the downward impact process of the piston hammer 7.

[0035] The working process of this invention in drilling operations is as follows:

[0036] This invention is used in conjunction with a high-pressure hydraulic press. High-pressure hydraulic fluid flows through a high-pressure delivery pipe from the inlet to the upper connector of the impactor. The upper connector is connected to the outer casing via a threaded rotation, with a sealing ring in between to ensure a sealed environment. The lower end of the outer casing engages with the drill bit housing via a spline structure. The upper cylinder liner and guide sleeve have a clearance fit. The lower end of the guide sleeve has a groove at the outer casing, allowing it to be locked in a fixed position via an interference fit. The "I"-shaped structure on the upper part of the valve ensures its movement remains within the upper and lower range of the limiting pad. The piston hammer guide sleeve and the sleeve structure at the lower part of the piston hammer prevent deviation from the center position of the impact anvil even under repeated impacts. The drill bit, fixed in place by the guide bushing and the stop ring, forms an integral unit with the valve control mechanism. The drill bit is fixed to the outer casing via a spline, and is fixed in both longitudinal and lateral positions. The impact force of the impact anvil is directly transmitted to the drill bit, thereby suppressing the generation of vibrations in all directions. This ensures that the entire drill bit continuously and stably breaks up the formation, improving drilling efficiency.

[0037] A valve-type double-acting hydraulic impact method that can improve working performance is characterized by comprising the following steps:

[0038] S1. Under natural conditions, both the piston hammer 8 and the valve 6 are in their lowest positions under the influence of gravity.

[0039] The selected location was a simulated gas well drilling site in the southern Sichuan Basin, at a depth of 2400m. The rock was predominantly brown, dense, massive quartz-feldspar silty mudstone. Therefore, based on core sampling and analysis, the local starting pressure P1 was set at 18 MPa. max The pressure was 20 MPa, and computer simulations were performed.

[0040] S2. The pressure of the liquid input from the top includes the starting value and the upper limit value. When the pressure is greater than the upper limit value, the high-pressure liquid sent from the inlet flows into the nozzle 3 from the center hole 26 of the upper connector 1 and forms a high-speed jet. It enters the inner cavity of the valve 6 and flows into the annular cavity 22 formed by the valve 6 and the piston hammer 8 from the side drain hole 21 at the bottom of the inner cavity. A large amount of liquid normally enters the center water hole 19 of the piston hammer. Because of the entrainment effect formed by the high-speed jet generated by the nozzle in the inner and outer cavities, the outer cavity 23 is a high-pressure area and the inner cavity 25 with a fast flow rate is a low-pressure area, which forces the lighter valve 6 to move upward rapidly until the water passage hole 24 is blocked.

[0041] After the valve 6 rises, the lifting hammer groove 17 has the effect of throttling and pressurizing, causing the piston hammer 7 to move upward at different speeds. The piston hammer 7 begins to move upward to the step 20 and contacts the valve 6 to block the central liquid flow channel.

[0042] During normal drilling of a vertical well, the drill string consists of several drill pipes with an outer diameter of 127.0 mm, an inner diameter of 112.0 mm, a drilling pressure of 0-200 kN, a cam stroke of 10 mm, and an elastic modulus of 206 GPa for the drill string steel.

[0043] S3. At this time, the channel from the annular cavity 22 to the center water hole 19 of the piston hammer is blocked. After the channel is blocked, the upper part of the valve 6 is under much greater pressure than the lower part, which produces a water hammer effect. The valve 6 quickly moves down to the lowest position, and at the same time the piston hammer 7 moves downward.

[0044] When the piston hammer 7 moves upward to its limit, the sleeve structure of the lower section of the piston hammer separates from the impact anvil, and the high-pressure liquid flow in the central liquid flow channel 19 of the piston hammer is quickly released into the outer drainage channel 18 of the impact anvil. The internal pressure is reduced in a short time, and only a small amount of liquid flow exists, which will not weaken the impact force of the piston hammer 7. The depressurization process will not affect the downward impact process of the piston hammer 7.

[0045] The high-pressure liquid in the central fluid flow channel 19 flows out from the outer drainage channel 18 and enters the central water hole of the drill bit through the gap 10. After being ejected from the nozzle of the drill bit 16, it assists in rock breaking and cuttings removal.

[0046] When the thrust is 10mm and the actual drilling pressure is 40-60kN, the drilling tool's impact energy is required to break rocks in medium-hard formations of 300-450J.

[0047] S4. Due to the increased pressure, the piston hammer 8 accelerates downward under pressure and moves quickly to the lowest point to hit the upper surface of the impact anvil 9. The impact anvil 9 transmits the impact force evenly to the drill bit assembly and achieves rock breaking through the drill bit 16. Under the restriction of the spline section 14, the drill bit assembly only moves axially and does not rotate circumferentially.

[0048] During the test, the entire tool was first lifted about 100mm off the bottom of the well, the pump was turned on to increase the displacement to 30L / s, and after the operation was stable, the drill string was lowered and the drilling pressure was increased to 40kN. Parameters such as drilling speed, impact frequency, pump pressure, impact energy, and power consumption were recorded.

[0049] S5. After the piston hammer 8 strikes the anvil 10, the valve 6 is limited and braked by the limiting pad 5, and the piston hammer 8 returns to its initial position after moving to the lowest point. Both the valve hammer 6 and the piston hammer 8 are at the lowest point. The pressure in the outer cavity 23 and the inner cavity 25 reappears as in S2. The valve 6 rises again and waits for the piston hammer 8 to rise again. Then, the water hammer effect is generated again, causing the piston hammer 8 to impact the anvil 10, thus achieving hydraulic impact.

[0050] The drilling pressure was successively reduced to 35, 30, 25, 20, 15, 10, and 5 kN, and the above parameters were recorded. The displacement was increased to 40 L / s, and the test was repeated.

[0051] S6. Through the above steps, the device provided by the present invention achieves a drilling speed of 8.61 m / h in core testing; the impact function reaches 400-600 J, which is 133% faster than conventional drilling tools and reduces the failure rate by 20%.

[0052] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A jet-suction type hydraulic impactor with improved working performance, characterized in that, The drill bit assembly includes a connecting section, a suction section, an impact section, and an outer casing. The connecting section is an upper connector (1) for connecting to the upper drill pipe. Below the upper connector (1) is a suction section, which includes a nozzle (3), a nozzle holder (4), and a valve (6). The impact section includes a piston hammer (7), an impact anvil (9), and the outer casing of the drill bit assembly includes an outer casing tube (8). The valve (6) is used to reciprocate relative to the outer casing tube (8) due to the entrainment effect and water hammer effect formed by the high-pressure driving fluid, driving the piston hammer (7) to periodically strike the impact anvil (9). The impact energy received by the impact anvil (9) is transmitted to the drill bit assembly connected to it for rock breaking by impact. ; Flow channels are provided in the connecting section, the suction section, and the impact section to allow the liquid to flow from top to bottom, and the liquid drives the suction section to move to transmit power to the impact section; The piston hammer (7) is a hollow cylinder with four drainable hammer grooves at the bottom that run through the top and bottom. The inner wall of the piston hammer (7) includes upper and lower sections; The upper section of the piston hammer (7) has four steps from top to bottom: the inner diameter of the first section is smaller than the inner diameter of the second section, the inner diameter of the second section is larger than the inner diameter of the third section, forming an annular cavity (22), the inner diameter of the third section is smaller than the inner diameter of the fourth section, the third section and the fourth section serve as the central liquid flow channel (19), and the inner diameter of the first section matches the outer diameter of the middle section of the valve (6). The lower outer diameter of the inner diameter of the small valve (6) of the third section forms a shoulder (20) for opening and closing the central water passage; the lower section of the piston hammer (7) is an inwardly concave cylindrical section, and the four hammer lifting grooves play a role in throttling and pressurizing to discharge the liquid flow into the central channel of the impact anvil (9), so that the piston hammer (7) is raised and the inner wall is fitted on the outside of the impact anvil (9); the upper side of the outer wall of the piston hammer (7) is provided with three layers with the diameter increasing from top to bottom, and a piston hammer guide sleeve is provided on the upper outer side, which matches the outer diameter of the first layer on the upper side of the outer wall of the piston hammer (7); the side of the central liquid flow channel (19) does not penetrate the valve as conventionally designed. The lateral throttling holes on the wall of the piston hammer (7) increase the mass of the piston hammer and further improve the impact force. There is an annular space between the piston hammer (7) and the outer casing tube (8) as an outer drainage channel (18). The valve (6) is a hollow cylinder. The outer wall of the valve (6) includes three sections: upper, middle and lower. The upper section of the valve (6) is a cylindrical section with a diameter 2-3 mm smaller than that of the outer casing tube (8) and a thickness of 30 mm. It is used to limit the upper and lower displacement limits of the valve (6) and the opening and closing of the water passage (24). The inner cavity of the valve (6) is a smooth cylindrical surface with a radial runout tolerance of 0.01~0.03 mm and a surface roughness Ra value of 0.63~0.

16. The valve slides up and down along the lower outer circle of the nozzle (4). The middle section of the valve (6) is a smooth cylindrical surface that slides and seals with the limiting guide sleeve (5). The lower section of the valve (6) protrudes outward by 10mm and has a 5mm rounded corner. The radial runout tolerance is 0.01~0.03mm, and the surface roughness Ra value is 0.63~0.

16. The valve (6) has a side drain hole (21), the bottom surface is a closed concave structure with a concave circle radius of 25mm, and the side drain hole (21) has a diameter of 40mm.

2. The jet-suction type hydraulic impactor with improved working performance according to claim 1, characterized in that, The upper connector (1), nozzle (3), spray receiver (4), limit guide sleeve (5), valve (6), and piston hammer (7) are all hollow in the middle, forming a flow channel from top to bottom as the central waterway. The opening and closing of the central waterway enables reciprocating motion and impacts and breaks rocks in the process. The nozzle (3) is installed in the center hole (26) of the upper connector (1). A limiting step is provided at the lower outer side of the nozzle (3). The nozzle (3) is limited and fixed by the limiting step at the upper end of the nozzle holder (4) that extends into the center hole (26). The nozzle holder (4) is limited and fixed by the limiting step at the lower end of the nozzle holder (4) and the outer shell tube (8). The limiting guide sleeve (5) is installed in the groove in the middle section of the outer shell tube (8). The groove limits the upper and lower parts. The limiting guide sleeve (5) is a left-right symmetrical split type. During installation, it is installed in an alternating manner. In order to ensure that there is a gap of 1-2mm between the outer diameter of the installation and the outer shell tube (8), there is a gap of 2-3mm between the lower inner diameter and the upper end of the piston hammer (7).

3. The jet-suction type hydraulic impactor with improved working performance according to claim 2, characterized in that: The nozzle (4) has an inner cavity (25) in the middle and an outer cavity (23) formed by the lower end of the nozzle (6) and the upper end of the valve (6). It is connected by six water holes (24). The high-pressure liquid flows into the nozzle (3) from the center hole (26) of the upper connector (1) and is sprayed to form a high-speed jet. When the high-speed jet passes through the inner cavity (25), there is a velocity difference with the surrounding liquid, which reduces the pressure in the inner cavity (25). The liquid in the inner cavity (25) and the outer cavity (23) form a pressure difference. The liquid in the outer cavity (23) will be drawn into the space of the inner cavity (25) through the water holes (24) under the action of the pressure difference. It is carried by the high-speed jet flowing out of the nozzle (3) through the center channel of the valve (6) and the lower center water hole of the piston hammer. It enters the drill bit through the center water hole of the impact anvil (9) to assist the drill bit in breaking the rock. The liquid will carry the debris and return upward from the outer ring space of the impactor.

4. The jet-suction type hydraulic impactor with improved working performance according to claim 3, characterized in that: The upper connector (1) is connected to the upper inner side of the outer casing tube (8) through a threaded section provided on the lower side, and a sealing ring (2) is provided between the upper connector (1) and the outer casing tube (8). The lifting hammer groove has an orifice diameter of 10mm, achieving a maximum flow rate of 2.26m³ / h. 3 / h, the lifting groove (17) has the effect of throttling and pressurizing, so that the piston hammer moves upward at a variable speed; when the upward speed of the piston hammer (7) is 0m / s, it is the maximum displacement of the piston hammer (7). The lower sleeve-shaped structure separates from the impact anvil (9), and a large amount of liquid in the central liquid flow channel of the piston hammer flows into the outer drainage channel (18) and then enters the drill bit (16) from the gap (10) and flows to the external space. In a short time, the pressure in the cavity is reduced, and only a small amount of liquid exists, which will not weaken the impact force of the piston hammer (7) on the impact anvil (9), and the pressure relief process will not affect the impact process of the piston hammer (7).

5. The jet-suction type hydraulic impactor with improved working performance according to claim 4, characterized in that: The impact anvil (9) has a central drainage hole. The drill bit (16) is located below the impact anvil (9). The impact anvil (9) transmits the impact force to the upper spline-free part (12) of the drill bit (16). The drill bit (16) has a head and a shank. The shank consists of a splined section (14) and a spline-free part (12). The spline-free part (12) has a guide bushing (11). A stop ring (13) is sandwiched between the guide bushing and the sleeve (15) to prevent the drill bit from falling off. The stop ring (13) is axially split for easy installation. The drill bit (16) can move axially between its rear end and front end. The axial movement distance of the drill bit is limited, and it cannot rotate relative to the outer casing tube (8). The drill bit (16) has a central channel from its shank to the front end of the drill bit for discharging driving fluid to assist in rock breaking. The upper end of the drill bit assembly is connected to the lower part of the impact anvil (9). The upper part of the outer diameter surface of the drill bit assembly is provided with a non-splined part (12) to ensure that the drill bit assembly will not come out of the outer shell tube (8) when moving up and down. The middle part of the drill bit assembly is provided with a splined section (14). An inner spline matching the splined section (14) is provided on the inner side of the outer shell tube (8) to ensure that the drill bit can move up and down along the inner spline and prevent the drill bit assembly from rotating. An impact drill bit (16) is provided below the splined section (14). The impact drill bit (16) is located on the lower side of the outer shell tube (8), and the outer diameter of the impact drill bit (16) is larger than that of the splined section (14). The step between the impact drill bit (16) and the splined section (14) maintains the limit displacement of the drill bit assembly moving upward.

6. The jet-suction type hydraulic impactor with improved working performance according to claim 5, characterized in that: The upper connector (1) is connected to the upper inner side of the outer casing tube (8) through a threaded section provided on the lower side, and a sealing ring (2) is provided between the upper connector (1) and the outer casing tube (8).

7. A method for using a suction-type hydraulic impactor as described in claim 6, characterized in that, Includes the following steps: S1. Under natural conditions, the piston hammer (7) and the valve (6) are both in their lowest positions under the influence of gravity. S2. The pressure of the liquid input from the top includes the starting value and the upper limit value. When the pressure is greater than the upper limit value, the high pressure liquid sent from the inlet flows into the nozzle (3) from the center hole (26) of the upper connector (1), and sprays to form a high-speed jet. It enters the inner cavity of the valve (6) and flows into the annular cavity (22) formed by the valve (6) and the piston hammer (7) from the side drain hole (21) at the bottom of the inner cavity. A large amount of liquid normally enters the central water hole of the piston hammer. Because of the suction effect formed by the high-speed jet generated by the nozzle in the inner and outer cavities, the outer cavity (23) is a high-pressure area and the inner cavity (25) with a fast flow rate is a low-pressure area, which forces the lighter valve (6) to move upward rapidly until the water passage (24) is blocked. After the valve (6) rises, the lifting groove (17) has the effect of throttling and pressurizing, causing the piston hammer (7) to move upward at different speeds. The piston hammer (7) begins to move upward to the shoulder (20) and contacts the valve (6) to block the central liquid flow channel. S3. At this time, the channel from the annular cavity (22) to the center fluid channel (19) of the piston hammer is blocked. After the channel is blocked, the upper part of the valve (6) is under much greater pressure than the lower part, resulting in a water hammer effect. The valve (6) moves down to the lowest position quickly, and at the same time the piston hammer (7) moves downward. When the piston hammer (7) moves upward to its limit, the sleeve structure of the lower section of the piston hammer separates from the impact anvil, and the high pressure liquid flow in the central liquid flow channel (19) of the piston hammer is quickly released into the outer drainage channel (18) of the impact anvil; the internal pressure is reduced in a short time, and only a small amount of liquid flow exists, which will not weaken the impact force of the piston hammer (7), and the depressurization process will not affect the downward impact process of the piston hammer (7); The high-pressure liquid in the central fluid flow channel (19) of the piston hammer flows out from the outer drainage channel (18) and enters the central water hole of the drill bit through the gap (10). After being ejected from the nozzle of the drill bit (16), it assists in rock breaking and chip removal. S4. Due to the increased pressure, the piston hammer (7) accelerates downward under pressure and moves quickly to the lowest point to hit the upper surface of the impact anvil (9). The impact anvil (9) transmits the impact force evenly to the drill bit assembly and achieves rock breaking through the drill bit (16). Under the restriction of the spline section (14), the drill bit assembly only moves axially and does not rotate circumferentially. S5. After the piston hammer (7) strikes the impact anvil (9), the valve (6) is limited and braked by the limiting guide sleeve (5), and the piston hammer (7) returns to its initial position in its natural state after moving to the lowest position. The valve (6) and the piston hammer (7) are both at the lowest position. The pressure in the outer cavity (23) and the inner cavity (25) reappears as in S2. The valve (6) rises again and waits for the piston hammer (7) to rise again. Then, the water hammer effect is generated again, causing the piston hammer (7) to strike the anvil (9) and realize the hydraulic impact.

8. The valve-type double-acting hydraulic impact method for improving working performance as described in claim 7, characterized in that, In step S2, when the pressure is less than the limit value and greater than the starting value, after starting, the valve (6) will not quickly reach the upper limit position. Instead, under the combined effect of its own weight, overcoming the downward impact force at the convex cone, and the upward pressure of the annular cavity (22), it will stop at a certain point during the upward movement and will not reach the upper limit position. At the same time, the displacement limit of the piston hammer (7) will also change accordingly. It will not reach the highest position in step S2 and will instead move downward. This situation will not affect normal rock breaking, but it will reduce the impact energy of rock breaking.

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