An integrated tool and method for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe

Abstract

The present invention provides an integrated tool and method for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe. The integrated tool comprises a drill pipe, a No. 2 rupture disk, a mechanical release, a double-flap check valve, a sliding sleeve hydraulic ejector, a well cleaning gauge, a No. 1 rupture disk and a guide shoe, which are fixedly connected in sequence from top to bottom. The guide shoe is configured to prevent the tool from getting stuck during the well entry process; the well cleaning gauge is configured to scrape the inner wall of the wellbore when the tool is in the wellbore; the hydraulic ejector is configured to perform jet perforation operations; the No. 1 rupture disk and the No. 2 splitting disk respectively block the end and front end of the pipe column; and the double-flap check valve is configured to close the inner cavity of the pipe column after the perforation operation. The method comprises the steps of: assembling a tool string; drilling down; circulating a drag reducer; cleaning the well; positioning and depth calibration; establishing an ejection channel; hydraulic sandblasting perforation; and a second perforation operation. The present invention has the advantages of repeatable perforation, completing well cleaning and transmission perforation operations in one drilling trip, shortening the construction period, and reducing well control risks.

Description

Technical Field

[0001] The invention relates to the technical field of staged fracturing transformation of horizontal well reservoirs in low-permeability oil and gas fields, and in particular to an integrated tool and method for transmitting well flushing and perforating with a long horizontal section of pressurized drill pipe. Background Art

[0002] With the large-scale development of shale oil, tight gas and shale gas in the Ordos Basin, the horizontal well + casing completion + bridge shot segmented volume fracturing process has become the main process technology for segmented fracturing transformation of low permeability oil and gas fields and improving single well production. Horizontal wells with long horizontal sections can increase the reservoir contact area to a greater extent, and are an effective means to increase single well production and ultimate oil and gas recovery, reduce drilling and completion costs, and improve economic benefits. The number of ultra-long horizontal wells put into development in oil and gas fields is increasing. The longest horizontal sections of shale oil and tight gas are both over 5000m, the longest horizontal section reaches 5265m, and the well depth reaches 8258m. Ultra-long horizontal section wellbore engineering has put forward higher requirements for downhole operations.

[0003] At present, the ultra-long horizontal wells in the Changqing area do not use toe-end sliding sleeves for the first section of the layer opening operation. Usually, 2-inch continuous tubing is used for horizontal well cleaning and first section perforation operations. However, due to the natural bending stress of the continuous tubing, a "spiral self-locking" effect will occur in the wellbore, resulting in a limited depth of the continuous tubing in the horizontal well, which in turn limits the promotion of ultra-long horizontal wells. At present, the horizontal sections above 3500m that have been completed use large drilling rigs + drill pipe conventional operation transmission to complete the cleaning and first section of perforation layer opening operations. It is necessary to pull the string twice to complete the cleaning and perforation operations. The operation cycle of a single well is more than 15 days, with a long operation cycle, high construction costs, and high well control risks. At the same time, during the ultra-long horizontal section reservoir transformation or completion production process, there may be abnormal falling objects in the wellbore, sand plugging and other working conditions, which exceed the capacity of the continuous tubing well repair operation. Wellbore maintenance operations such as salvage, well cleaning and sand flushing require an operation method with accessible strings and controlled well control risks.

[0004] The Sichuan Changning 209H35-5 well in the Sichuan-Chongqing shale gas field encountered obstacles many times when using drilling rigs, continuous tubing, and cables for creeping perforation, and was unable to reach the predetermined perforation position. The pressure equipment can press down the pipe string and rotate the pipe string to successfully complete the pressure drill pipe well and transmit the conventional perforating gun operation. The horizontal section is 2400m long. However, this technology has the following defects:

[0005] 1. The existing technical solution is to carry drill pipes through the drilling rig to clean the well and transmit the perforating gun. Since the perforating gun is a traditional fire perforating gun, it is detonated by hydraulic pressure difference after being lowered to the predetermined position. The inside of the perforating gun is a closed structure, and no liquid can be pumped during the lowering process. Therefore, it is necessary to lower the drill pipe to complete the well cleaning operation and replace the drag reducer solution during the operation; lower the perforating gun for the second time, and pressurize the inside and outside of the pipe column to detonate the perforating gun to complete the perforating operation. The operation cycle is long and the cost is high.

[0006] 2. The traditional drilling rig with drill pipe operation mode is adopted. After perforating, it is necessary to replace the well with a hydraulic well to kill the well. There is no blowout device in the pipe string, and the drilling rig does not have the operating conditions for lifting the pipe string under pressure. If overflow occurs during the long-term opening of the wellhead, it is difficult to control, and there is a greater risk of well control.

[0007] 3. The traditional perforation method is pressure differential detonation, and detonators of different pressure levels are installed inside and outside the pipe string. Therefore, only two perforating guns can be carried, and pressure detonation is applied inside and outside the pipe string respectively. Due to the heterogeneity of the formation, it may be impossible to establish a sufficient liquid channel, and the secondary perforation requires the pipe string to be re-tripped. With the integrated operation tool, the jet tool can repeatedly complete multiple perforation operations, ensuring that the flushing and perforation operations are completed in one trip of the pipe string. Summary of the invention

[0008] The purpose of the present invention is to solve at least one of the above-mentioned deficiencies in the prior art. For example, one of the purposes of the present invention is to provide a long horizontal section pressure drill pipe transmission, well cleaning and perforation integrated tool, and another purpose of the present invention is to provide a long horizontal section pressure drill pipe transmission, well cleaning and perforation integrated method.

[0009] In order to achieve the above-mentioned objectives, the present invention provides, on the one hand, an integrated tool for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe, wherein the integrated tool comprises a drill pipe, a No. 2 rupture disk, a mechanical release, a double-flap one-way valve, a sliding sleeve hydraulic ejector, a well clearing gauge, a No. 1 rupture disk and a guide shoe which are fixedly connected in sequence from top to bottom, wherein the guide shoe is configured to prevent the tool from getting stuck during the well entry process and to straighten the tool string; the well clearing gauge is configured to scrape the inner wall of the wellbore during the lowering of the integrated tool; the sliding sleeve hydraulic ejector is configured to establish a channel inside and outside the tubing string for jet perforation operations; the No. 1 rupture disk blocks the end of the tubing string, and the No. 2 splitting disk is configured to block the front end of the tubing string; the double-flap one-way valve is configured to close the inner cavity of the tubing string after the jet perforation operation to prevent gas and liquid from moving up from the tubing string to cause a well control hazard.

[0010] In an exemplary embodiment of one aspect of the present invention, during the lowering of the pipe string, the drill pipe may be a closed structure, and the drill pipe and the drilling tool may be lowered by their own weight.

[0011] In an exemplary embodiment of one aspect of the present invention, the inner cavity of the drill pipe between the No. 2 rupture disk and the No. 1 rupture disk can be closed air. The upward buoyancy generated by the density difference between the inside and outside of the pipe string can reduce the positive pressure of the horizontal section of the drill pipe on the casing wall during the lowering process, reduce the sliding friction, and increase the depth of the pipe string.

[0012] In an exemplary embodiment of one aspect of the present invention, all downhole tools may be threaded structures, which are sequentially connected to the drill pipe by threads, and are lowered into the set well washing and first-stage perforation depths by using the deadweight of the drill pipe and the thrust applied by the pressure equipment;

[0013] The well-drilling gauge may contain a ball seat.

[0014] Another aspect of the present invention provides an integrated method for perforating and cleaning a well by transmitting a long horizontal section of pressurized drill pipe. The integrated method for perforating and cleaning a well may include the following steps:

[0015] Assemble tool strings;

[0016] Drill down;

[0017] Circulating drag reducer;

[0018] washing wells;

[0019] Positioning and depth calibration;

[0020] Establishing jet channels;

[0021] Hydraulic sandblasting perforation;

[0022] Second perforation construction.

[0023] In an exemplary embodiment of another aspect of the present invention, the drilling down may include:

[0024] The tool strings are connected in sequence, and the tool string is lowered to a position that can be reached by the drill pipe's own weight by relying on the downward thrust provided by the drill pipe. A No. 2 rupture disk is connected to the drill pipe to seal off a section of air inside the drill pipe. At the same time, metal drag reducer fluid is injected from the wellhead drill pipe to the top of the No. 2 rupture disk to increase the axial thrust of the vertical well section tubing and lower the tool string into a deeper well section.

[0025] In an exemplary embodiment of another aspect of the present invention, the circulating drag reducer may include:

[0026] When the drill pipe is continuously lowered and its deadweight drops to zero due to the self-locking of the pipe string and it cannot be lowered by its own weight, the pump is turned on to open the No. 2 rupture disk and the No. 1 rupture disk in turn, and at the same time, the metal drag reducer solution is pumped in a positive circulation until the casing is filled with the metal drag reducer solution; the metal drag reducer positive circulation pumping and drilling operations are repeated until the bottom of the artificial well is reached.

[0027] In an exemplary embodiment of another aspect of the present invention, the well washing may include:

[0028] Lift the drilling tool 1 to 3 meters, and perform positive circulation well washing according to the well washing fluid required by the construction design until the water color at the inlet and outlet meets the engineering design requirements;

[0029] The positioning depth calibration may include:

[0030] The depth of the drill pipe and tools lowered into the wellbore is calculated cumulatively, the drill pipe is adjusted and the position of the sliding sleeve hydraulic ejector is checked, and the tool string depth data is compared and calibrated.

[0031] In an exemplary embodiment of another aspect of the present invention, the pitching skid may include:

[0032] Adjust the position of the tool string so that the position of the sliding sleeve hydraulic ejector is aligned with the first layer design position, and then put a hollow ball into the drill pipe and continue to inject fluid into the drill pipe; the hollow ball passes through the drill pipe to open the sliding sleeve of the sliding sleeve hydraulic ejector, and the hollow ball continues to move downward to the ball seat of the well gauge to block the lower fluid flow channel;

[0033] The establishing of the injection channel may include:

[0034] The fluid changes its flow direction through the nozzle of the sliding sleeve hydraulic ejector, and the fluid that continues to be pumped from the drill pipe is throttled by the nozzle, making the pressure of the fluid inside the sliding sleeve hydraulic ejector higher than the external fluid pressure, producing an obvious throttling effect, and judging whether the sliding sleeve is open or not by the pressure.

[0035] In an exemplary embodiment of another aspect of the present invention, the hydraulic sandblasting perforation may include:

[0036] Inject sand-carrying fluid from the drill pipe, and the sand-carrying fluid flows out from the nozzle of the sliding sleeve hydraulic ejector through the drill pipe to form a high-speed sand-carrying jet to impact the inner wall of the casing. The abrasives such as quartz sand carried by the high-speed sand-carrying jet cut the casing, thereby penetrating the casing, eroding the cementing cement and the formation, realizing the perforation operation, and establishing a connecting channel between the wellbore and the formation.

[0037] The second perforation operation may include:

[0038] After displacing a wellbore volume, lift the drill pipe to adjust the drill bit, adjust the tool string to the second layer perforation construction position, repeat the above hydraulic sandblasting perforation steps to complete the first stage perforation opening construction.

[0039] Compared with the prior art, the beneficial effects of the present invention include at least one of the following:

[0040] (1) The integrated tool for transmitting, cleaning and perforating with a long horizontal section of pressure drill pipe of the present invention can repeatedly complete multiple perforating operations, so that the cleaning and perforating operations can be completed in one drilling trip, thus shortening the construction period and reducing the risk of well control;

[0041] (2) The integrated tool for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe of the present invention is used by installing a No. 2 rupture disk in the vertical well section, and pouring a prepared metal drag reducer solution into the upper part of the No. 2 rupture disk. The axial thrust of the drill pipe string in the vertical well section is increased by the liquid on the upper part of the rupture disk. The inner cavity of the drill pipe in the middle section between the No. 2 and No. 1 rupture disks is closed air. The upward buoyancy generated by the density difference between the inside and outside of the string can reduce the positive pressure of the horizontal section of the drill pipe on the casing wall during the lowering process, thereby reducing the sliding friction and increasing the depth of the string. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The above and other objects and / or features of the present invention will become more apparent through the following description in conjunction with the accompanying drawings, in which:

[0043] Figure 1 It shows one of the structural diagrams of the integrated tool string for transmitting, washing and perforating of a long horizontal well with pressure drill pipe of the present invention;

[0044] Figure 2 The second structural diagram of the integrated tool string for transmitting, washing and perforating a long horizontal well with pressure drill pipe of the present invention is shown;

[0045] Figure 3 The third structural diagram of the integrated tool string for transmitting, washing and perforating wells in a long horizontal well with pressure drill pipe of the present invention is shown.

[0046] The main reference numerals are described as follows:

[0047] 1-guide shoe, 2-No. 1 rupture disk, 3-well clearing gauge, 4-hollow ball, 5-sliding sleeve hydraulic ejector, 6-double-flap check valve, 7-mechanical loss, 8-No. 2 rupture disk, 9-drill pipe, 10-gas layer casing, 11-surface casing, 12-metal drag reducer, 13-sand carrying fluid, 14-formation. DETAILED DESCRIPTION

[0048] Hereinafter, an integrated tool and method for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe according to the present invention will be described in detail in conjunction with exemplary embodiments.

[0049] It should be noted that “first”, “second”, etc. are merely for the convenience of description and distinction and should not be understood as indicating or implying relative importance.

[0050] Figure 1 It shows one of the structural diagrams of the integrated tool string for transmitting, washing and perforating of a long horizontal well with pressure drill pipe of the present invention; Figure 2The second structural diagram of the integrated tool string for transmitting, washing and perforating a long horizontal well with pressure drill pipe of the present invention is shown; Figure 3 The third structural diagram of the integrated tool string for transmitting, washing and perforating wells in a long horizontal well with pressure drill pipe of the present invention is shown.

[0051] In a first exemplary embodiment of the present invention, Figures 1 to 3 As shown, a long horizontal section pressure drill pipe transmission well cleaning and perforating integrated tool is provided, and the integrated tool mainly comprises a drill pipe 9, a second rupture disk 8, a mechanical release hand 7, a double-flap check valve 6, a sliding sleeve hydraulic ejector 5, a well cleaning gauge 3, a first rupture disk 2 and a guide shoe 1, which are fixedly connected in sequence from top to bottom. Here, from top to bottom refers to the direction from the upstream to the downstream of the wellbore.

[0052] Among them, the front end of the guide shoe is a hemispherical structure, and its main function is to prevent the integrated tool from getting stuck during the well entry process and to straighten the tool string.

[0053] The well-drilling gauge is configured to scrape the inner wall of the wellbore during the running-in of the integrated tool.

[0054] The sliding sleeve hydraulic sprinkler is a closed structure before the ball is thrown. After the ball is thrown, the internal sleeve moves downward under the action of hydraulic force to establish communication between the inside and outside of the pipe string, providing an operating channel for the jet perforating operation through the nozzle.

[0055] The No. 1 rupture disk blocks the end of the tubing string, and the No. 2 splitting disk is configured to block the front end of the tubing string.

[0056] The double-flap check valve is configured to seal the inner cavity of the tubing string after the hydraulic jet perforating operation is completed, so as to prevent gas and liquid from moving upward from the tubing string and causing a well control hazard.

[0057] In this exemplary embodiment, during the lowering of the pipe string, the drill pipe may be in a closed structure, and the drill pipe and the drilling tool may be lowered by their own weight.

[0058] In this exemplary embodiment, the inner cavity of the drill pipe between the No. 2 rupture disk and the No. 1 rupture disk can be closed air, and the upward buoyancy generated by the density difference between the inside and outside of the pipe string can reduce the positive pressure of the horizontal section of the drill pipe on the casing wall during the lowering process, reduce the sliding friction and increase the depth of the pipe string. The casing includes an air layer casing 10 and a surface casing 11.

[0059] In this exemplary embodiment, all downhole tools can be threaded structures, which are connected to the drill pipe in turn through threads, and are lowered into the set well cleaning and first-stage perforation depths using the deadweight of the drill pipe and the thrust applied by the pressure equipment. The well cleaning gauge can contain a ball seat.

[0060] A second exemplary embodiment of the present invention provides an integrated method for perforating and cleaning a well by transmitting a long horizontal section of pressurized drill pipe. The integrated method for perforating and cleaning a well may include the following steps:

[0061] Assemble tool strings;

[0062] Drill down;

[0063] Circulating drag reducer;

[0064] washing wells;

[0065] Positioning and depth calibration;

[0066] Establishing jet channels;

[0067] Hydraulic sandblasting perforation;

[0068] Second perforation construction.

[0069] In this exemplary embodiment, the drilling down may include:

[0070] The tool strings are connected in sequence, and the tool string is lowered to a position that can be reached by the drill pipe's own weight by relying on the downward thrust provided by the drill pipe. A No. 2 rupture disk is connected to the drill pipe to seal off a section of air inside the drill pipe. At the same time, metal drag reducer fluid is injected from the wellhead drill pipe to the top of the No. 2 rupture disk to increase the axial thrust of the vertical well section tubing and lower the tool string into a deeper well section.

[0071] In this exemplary embodiment, the circulating drag reducer may include:

[0072] When the drill pipe is continuously lowered and its deadweight drops to zero due to the self-locking of the pipe string and it cannot be lowered by its own weight, the pump is turned on to open the No. 2 rupture disk and the No. 1 rupture disk in turn, and at the same time, the metal drag reducer solution is pumped in a positive circulation until the casing is filled with the metal drag reducer solution; the metal drag reducer positive circulation pumping and drilling operations are repeated until the bottom of the artificial well is reached.

[0073] In this exemplary embodiment, the well washing may include:

[0074] Lift the drill string 1 to 3 meters and perform positive circulation well washing with the well washing fluid specified in the construction design until the water color at the inlet and outlet meets the engineering design requirements.

[0075] The positioning depth calibration may include:

[0076] The depth of the drill pipe and tools lowered into the wellbore is calculated cumulatively, the drill pipe is adjusted and the position of the sliding sleeve hydraulic ejector is checked, and the tool string depth data is compared and calibrated.

[0077] In this exemplary embodiment, the pitching skid may include:

[0078] Adjust the position of the tool string so that the position of the sliding sleeve hydraulic ejector is aligned with the designed position of the first layer. Put a hollow ball into the drill pipe and continue to inject fluid into the drill pipe. The hollow ball passes through the drill pipe to open the sliding sleeve of the sliding sleeve hydraulic ejector, and the hollow ball continues to move downward into the ball seat of the well gauge to block the lower liquid flow channel.

[0079] The establishing of the injection channel may include:

[0080] The fluid changes its flow direction through the nozzle of the sliding sleeve hydraulic ejector, and the fluid that continues to be pumped from the drill pipe is throttled by the nozzle, making the pressure of the fluid inside the sliding sleeve hydraulic ejector higher than the external fluid pressure, producing an obvious throttling effect, and judging whether the sliding sleeve is open or not by the pressure.

[0081] In this exemplary embodiment, the hydraulic sandblasting perforation may include:

[0082] Sand-carrying fluid is injected into the drill pipe, and flows out from the nozzle of the sliding sleeve hydraulic ejector through the drill pipe, forming a high-speed sand-carrying jet to impact the inner wall of the casing. The quartz sand and other abrasives carried by the high-speed sand-carrying jet cut the casing, thereby penetrating the casing, eroding the cementing cement and the formation, realizing the perforating operation, and establishing a connecting channel between the wellbore and the formation.

[0083] The second perforation operation may include:

[0084] After displacing a wellbore volume, lift the drill pipe to adjust the drill bit, adjust the tool string to the second layer perforation construction position, repeat the above hydraulic sandblasting perforation steps to complete the first stage perforation opening construction.

[0085] Specifically, the integrated method for transmitting, washing and perforating a long horizontal section of pressurized drill pipe in this embodiment mainly includes the following steps:

[0086] (1) Assembly tool string: Figures 1 to 3 As shown, the long horizontal section pressure drill pipe transmission well cleaning and perforating integrated tool string consists of a guide shoe 1, a No. 1 rupture disk 2, a well clearing gauge 3 (including a ball seat), a sliding sleeve hydraulic ejector 5, a double-flap check valve 6, a mechanical release hand 7 and a No. 2 rupture disk 8 from bottom to top. The upper and lower ends of the No. 2 rupture disk 8 are connected to the drill pipe 9, and the mechanical release hand 7 is connected and fixed to the end of the drill pipe by means of threads or the like. Other tool accessories are connected together in sequence by threads, and the construction work is carried out by lowering the drill pipe into the wellbore of the casing completion (hereinafter, the direction of the drill pipe is taken as the upper direction); the casing includes a gas layer casing 10 and a surface casing 11.

[0087] (2) Drilling: Connect the tool strings in sequence, and use the downward thrust provided by the drill pipe to lower the tool string into a position that can be reached by the drill pipe's own weight. Connect the No. 2 rupture disk 8 to the drill pipe to seal off a section of air inside the drill pipe. At the same time, inject the metal drag reducer 12 fluid from the wellhead drill pipe to the top of the No. 2 rupture disk 8 to increase the axial thrust of the vertical well section pipe string and lower the tool string into a deeper well section.

[0088] (3) Circulating drag reducer: When the drill pipe is continuously lowered and its deadweight is reduced to 0 due to the self-locking of the pipe string and it cannot be lowered by its own weight, the pump is turned on to open the No. 2 rupture disk 8 and the No. 1 rupture disk 2 in sequence, and at the same time, the metal drag reducer solution is pumped in a positive circulation until the casing is filled with the metal drag reducer solution; the metal drag reducer positive circulation pumping and drilling operation are repeated until the bottom of the artificial well is reached.

[0089] (4) Well washing: lift the drill string 1 to 3 meters and perform positive circulation well washing with the well washing fluid specified in the construction design until the water color at the inlet and outlet meets the engineering design requirements.

[0090] (5) Positioning and depth calibration: Accumulate and calculate the depth of the drill pipe and tools lowered into the wellbore, adjust the drill pipe and calibrate the 5 positions of the sliding sleeve hydraulic ejector, and compare and calibrate the tool string depth data.

[0091] (6) Throwing a ball to hit the sliding sleeve: Adjust the position of the tool string so that the position of the sliding sleeve hydraulic ejector 5 is aligned with the designed position of the first layer. Throw a hollow ball 4 into the drill pipe and continue to inject fluid into the drill pipe. The hollow ball 4 passes through the drill pipe to open the sliding sleeve of the sliding sleeve hydraulic ejector 5. The hollow ball 4 continues to move downward to the ball seat of the well gauge 3 to block the lower liquid flow channel.

[0092] (7) Establishing an injection channel: The fluid changes its flow direction through the nozzle of the sliding sleeve hydraulic ejector 5. The fluid that continues to be pumped from the drill pipe is throttled by the nozzle, so that the pressure of the fluid inside the sliding sleeve hydraulic ejector 5 is higher than the pressure of the external fluid, resulting in an obvious throttling effect. Whether the sliding sleeve is open is determined by the pressure.

[0093] (8) Hydraulic sandblasting perforation: a sand-carrying fluid 13 is injected into the drill pipe, and the sand-carrying fluid flows out from the nozzle of the sliding sleeve hydraulic ejector 5 through the drill pipe, forming a high-speed sand-carrying jet to impact the inner wall of the casing. The abrasives such as quartz sand carried by the high-speed sand-carrying jet cut the casing, thereby penetrating the casing, eroding the cementing cement and the formation, and realizing the perforation operation, thereby establishing a connecting channel between the wellbore and the formation 14.

[0094] (9) Second perforation construction: After displacing one wellbore volume, lift the drill pipe to adjust the drill bit, adjust the tool string to the second layer perforation construction position, repeat the above step (8) to complete the first stage perforation construction.

[0095] In summary, the advantages of the present invention may include at least one of the following:

[0096] (1) The integrated tool for transmitting, cleaning and perforating with a long horizontal section of pressure drill pipe of the present invention can repeatedly complete multiple perforating operations, so that the cleaning and perforating operations can be completed in one drilling trip, thus shortening the construction period and reducing the risk of well control;

[0097] (2) The integrated tool for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe of the present invention is used by installing a No. 2 rupture disk in the vertical well section, and pouring a prepared metal drag reducer solution into the upper part of the No. 2 rupture disk. The axial thrust of the drill pipe string in the vertical well section is increased by the liquid on the upper part of the rupture disk. The inner cavity of the drill pipe in the middle section between the No. 2 and No. 1 rupture disks is closed air. The upward buoyancy generated by the density difference between the inside and outside of the string can reduce the positive pressure of the horizontal section of the drill pipe on the casing wall during the lowering process, thereby reducing the sliding friction and increasing the depth of the string.

[0098] Although the present invention has been described above by combining with exemplary embodiments, it will be apparent to those skilled in the art that various modifications and changes may be made to the exemplary embodiments of the present invention without departing from the spirit and scope defined in the claims.

Claims

1. A long horizontal section pressure drill pipe transmission well cleaning and perforating integrated tool, characterized in that: The integrated tool comprises a drill pipe, a No. 2 rupture disk, a mechanical release, a double-flap check valve, a sliding sleeve hydraulic ejector, a well-drilling gauge, a No. 1 rupture disk and a guide shoe, which are fixedly connected in sequence from top to bottom. The guide shoe is configured to prevent the tool from getting stuck during the well entry process and to straighten the tool string; The well-drilling gauge is configured to scrape the inner wall of the wellbore during the running of the integrated tool; The sliding sleeve hydraulic ejector is configured to establish a channel inside and outside the pipe string to perform an ejection perforation operation; The No. 1 rupture disk blocks the end of the pipe string, and the No. 2 rupture disk is configured to block the front end of the pipe string. The inner cavity of the drill pipe between the No. 2 rupture disk and the No. 1 rupture disk is closed air. The upward buoyancy generated by the density difference between the inside and outside of the pipe string reduces the positive pressure of the horizontal section of the drill pipe on the casing wall during the lowering process, reduces the sliding friction and increases the depth of the pipe string. The double-flap one-way valve is configured to seal the inner cavity of the tubing string after the jet perforation operation to prevent gas and liquid from moving upward from the tubing string to cause a well control hazard.

2. The long horizontal section pressure drill pipe transmission and well washing and perforating integrated tool according to claim 1 is characterized in that: During the lowering of the pipe string, the drill pipe is a closed structure, and the pipe string is lowered by relying on the deadweight of the drill pipe and the drilling tool.

3. The integrated tool for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe according to claim 1 is characterized in that: All downhole tools are threaded, connected to the drill pipe in turn through threads, and lowered to the set well-washing and first-stage perforating depths using the deadweight of the drill pipe and the thrust applied by the pressure equipment; The well-drilling gauge contains a ball seat.

4. The long horizontal section pressure drill pipe transmission and well washing and perforating integrated tool according to claim 1 is characterized in that: The operation method of the integrated well-flushing and perforating tool comprises the following steps: Assemble tool strings; Drill down; Circulating drag reducer; washing wells; Positioning and depth calibration; Establishing jet channels; Hydraulic sandblasting perforation; Second perforation construction.

5. The integrated tool for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe according to claim 4 is characterized in that: The drilling down includes: The tool strings are connected in sequence, and the tool string is lowered to a position that can be reached by the drill pipe's own weight by relying on the downward thrust provided by the drill pipe. A No. 2 rupture disk is connected to the drill pipe to seal off a section of air inside the drill pipe. At the same time, metal drag reducer fluid is injected from the wellhead drill pipe to the top of the No. 2 rupture disk to increase the axial thrust of the vertical well section tubing and lower the tool string into a deeper well section.

6. The integrated tool for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe according to claim 4 is characterized in that: The circulating drag reducer comprises: When the drill pipe is continuously lowered and its deadweight drops to zero due to the self-locking of the pipe string and it cannot be lowered by its own weight, the pump is turned on to open the No. 2 rupture disk and the No. 1 rupture disk in turn, and at the same time, the metal drag reducer solution is pumped in a positive circulation until the casing is filled with the metal drag reducer solution; the metal drag reducer positive circulation pumping and drilling operations are repeated until the bottom of the artificial well is reached.

7. The integrated tool for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe according to claim 4 is characterized in that: The well washing comprises: Lift the drill bit 1 to 3 meters, and perform positive circulation well washing according to the well washing fluid required by the construction design until the water color at the inlet and outlet meets the engineering design requirements; The positioning depth calibration comprises: The depth of the drill pipe and tools lowered into the wellbore is calculated cumulatively, the drill pipe is adjusted and the position of the sliding sleeve hydraulic ejector is checked, and the tool string depth data is compared and calibrated.

8. The integrated tool for transmitting well cleaning and perforating with a long horizontal section of pressurized drill pipe according to claim 4 is characterized in that: The method for operating the integrated well-washing and perforating tool further includes throwing a ball into the sliding sleeve, The pitching sliding sleeve comprises: Adjust the position of the tool string so that the position of the sliding sleeve hydraulic ejector is aligned with the first layer design position, and then put a hollow ball into the drill pipe and continue to inject fluid into the drill pipe; the hollow ball passes through the drill pipe to open the sliding sleeve of the sliding sleeve hydraulic ejector, and the hollow ball continues to move downward to the ball seat of the well gauge to block the lower fluid flow channel; The establishment of the injection channel comprises: The fluid changes its flow direction through the nozzle of the sliding sleeve hydraulic ejector, and the fluid that continues to be pumped from the drill pipe is throttled by the nozzle, making the pressure of the fluid inside the sliding sleeve hydraulic ejector higher than the external fluid pressure, producing an obvious throttling effect, and judging whether the sliding sleeve is open or not by the pressure.

9. The integrated tool for transmitting, washing and perforating a long horizontal section of a drill pipe under pressure according to claim 4 is characterized in that: The hydraulic sandblasting perforation comprises: Inject sand-carrying fluid from the drill pipe, and the sand-carrying fluid flows out from the nozzle of the sliding sleeve hydraulic ejector through the drill pipe to form a high-speed sand-carrying jet to impact the inner wall of the casing. The quartz sand abrasive carried by the high-speed sand-carrying jet cuts the casing, thereby penetrating the casing, eroding the cementing cement and the formation, realizing the perforation operation, and establishing a connecting channel between the wellbore and the formation. The second perforation construction includes: After displacing a wellbore volume, lift the drill pipe to adjust the drill bit, adjust the tool string to the second layer perforation construction position, repeat the above hydraulic sandblasting perforation steps to complete the first stage perforation opening construction.

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