Drill rod inner wall mud scraper and mud scraping method

Abstract

The invention relates to a drill rod inner wall mud scraper and a mud scraping method, and belongs to the technical field of drilling tool cleaning. The mud scraper comprises a shell, a leather cup is arranged on the outer wall of the shell, a plurality of control valves are arranged in the shell, and a pneumatic vibrator and an air storage chamber are arranged below the control valves; a battery pack is arranged above the shell and connected with an air pump. According to the mud scraper, mud on the inner wall of the drill rod can be scraped through the leather cup, the flexible structure of the leather cup is used for making contact with the inner wall of the drill rod, the mud scraper can be well attached to the inner wall of the drill rod, the diameter changing situation of the inner wall of the drill rod is effectively dealt with, and the more stable cleaning effect is provided; meanwhile, the liquid level change can be detected in real time through a laser distance measuring sensor at the bottom of the mud scraper, an alarm is given when necessary, and the possible shaft bottom overflow condition is predicted. Through the main technical means, the problems that a scraper of an existing mud scraper cannot be well attached to the inner wall of a drill rod, and overflow cannot be early warned are solved. And meanwhile, a solution is reserved for special situations such as self jamming and faults.

Description

Technical Field

[0001] The invention relates to a drill rod inner wall scraper and a scraping method, belonging to the technical field of drilling tool cleaning. Background Art

[0002] During the oil extraction process, the mud formed by the mixture of drilling fluid and underground muddy water will adhere to the drill pipe. During the drilling process, the mud attached to the outer and inner walls of the drill pipe will be taken out of the drilling platform, resulting in a waste of drilling fluid. At the same time, the drilling fluid on the drilling platform is easy to pollute the environment when it flows outward. In addition, the drilling fluid on the drilling platform solidifies into ice in low temperature weather, and it is easy to slip and fall when walking on the drilling platform, affecting production safety. In addition, the drilling fluid is alkaline and will corrode the drilling platform and mechanical equipment. In addition, the attached drilling fluid will also affect the drilling tool installation / release operation, so it is very necessary to remove the mud on the drill pipe.

[0003] The mud attached to the outer wall can be scraped off with a rubber hose wrapped around the drill pipe, but the mud attached to the inner wall is not easy to clean. Steam cleaning and diesel ignition incineration are currently used. However, these methods have problems such as unstable cleaning effect, high energy consumption, and lack of environmental protection, and cannot meet the on-site operation requirements.

[0004] The patent application with announcement number CN106194114A discloses a symmetrical spiral blade drill pipe inner wall scraper, which includes a core tube, a scraper group and a float. The core tube is a hollow vertical tube. The scrapers are equidistantly distributed around the core tube to form a scraper group. The scrapers are composed of an upper spiral blade and a lower spiral blade. The upper spiral blade and the lower spiral blade have opposite spiral directions and are symmetrically distributed up and down. The upper spiral blade and the lower spiral blade are connected at the connection point by a fillet transition. The inner edges of the upper spiral blade and the lower spiral blade are connected to the outer wall of the core tube through support arms respectively. The inner edge and the outer edge of the scraper group are concentric circles. The float is a container with a bottom and an upper opening. The upper opening of the float is connected to the lower opening of the core tube by a thread. The upper opening of the core tube is connected by a thread and is blocked. The invention can reduce waste and pollution, reduce pollution treatment costs, and effectively prevent freezing of water holes in drilling tools. The spiral scraper is easier to pass through the drill pipe joint and is not easy to get stuck.

[0005] The above-mentioned scraper can clean the inner wall of the drill pipe, but it uses its own gravitational potential energy as a power source to move downward. It is a passive scraper and cannot cope with special situations such as self-blocking and bottom hole overflow. The inner wall of the drill pipe has many diameter changes. At the diameter change point, it is not easy for traditional scrapers to solve the problem of self-blocking while ensuring a good fit between the scraper and the inner wall of the drill pipe, and the cleaning effect cannot be guaranteed; at the same time, the scraper cannot warn of possible overflow. With the advancement of intelligence and digitalization, this function should be placed in the scraper as a basic function. Therefore, it is necessary to design a drill pipe inner wall scraper and a scraping method to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide an active scraper to address the deficiencies of the prior art. The scraper has sufficient power, can effectively clean the mud, can cope with a variety of special situations through intelligent control, and is not easy to get stuck. By using a flexible structure such as a leather cup to contact the inner wall of the drill pipe, the scraper can better fit the inner wall of the drill pipe, effectively cope with the diameter change of the inner wall of the drill pipe, and provide a more stable cleaning effect; at the same time, the laser ranging sensor at the bottom of the scraper can detect the change of liquid level in real time and issue an alarm when necessary to predict possible bottom hole overflow. These main technical means are used to solve the problems of the existing scraper blade not being able to fit the inner wall of the drill pipe well and being unable to warn of overflow.

[0007] The technical solution of the present invention is: A drill pipe inner wall scraper includes a shell, a leather cup, a two-position three-way solenoid valve A, a two-position three-way solenoid valve B, a two-position three-way solenoid valve C, a proportional valve, a pneumatic vibrator, an air storage chamber, a battery pack, an air pump, a Hall sensor, a laser distance sensor and a pressure sensor, characterized in that: the shell is cylindrical, a leather cup is arranged on the circumferential surface of the shell, a two-position three-way solenoid valve A, a two-position three-way solenoid valve B, a two-position three-way solenoid valve C and a proportional valve are sequentially installed on the inner wall of the shell from top to bottom through a bracket, a pneumatic vibrator is arranged in the shell below the proportional valve, and an air storage chamber is fixed on the bottom port of the shell; a battery pack is arranged above the shell, and the battery pack is connected to an air pump. The internal device of the scraper is sealed inside it and isolated from the outside world to achieve the purpose of explosion-proof, corrosion-resistant and waterproof.

[0008] A pedometer is arranged on the top of the battery pack.

[0009] The pedometer comprises a base, a pedometer wheel bracket and a pedometer wheel. The pedometer wheel bracket is symmetrically mounted on the base through a pin shaft, and the pedometer wheel is movably mounted on the top end of the pedometer wheel bracket.

[0010] The base is provided with a torsion spring which can apply thrust to the pedometer wheel bracket.

[0011] A sink is arranged at the bottom center of the base, and the sink is connected to the air pump set.

[0012] An upper air port is provided on the base, and a lower air port is provided at the bottom of the shell. The lower air port is connected with the upper air port through a proportional valve and a connecting pipe to ensure that sufficient and adjustable air flow can pass through the air path, so that the air pressure of the upper air port and the lower air port can be balanced under normal mud scraping working conditions. The lower air port and the upper air port are connected with the air pump, the pneumatic vibrator and the air storage chamber through a two-position three-way solenoid valve A, a two-position three-way solenoid valve B, a two-position three-way solenoid valve C and a connecting pipe.

[0013] A laser distance sensor and a pressure sensor are installed at the bottom of the scraper. The laser distance sensor can detect the distance between the scraper and the mud surface in real time, and issue an alarm when necessary to predict possible bottom well overflow. The pressure sensor detects changes in the lower gas port pressure.

[0014] A method for scraping mud from the inner wall of a drill pipe, characterized in that it comprises the following steps: The method for scraping mud from the inner wall of a drill pipe comprises the following steps: Normal scraping: S1, lowering the scraper into the drill pipe, the leather cup of the scraper is opened and pressed against the inner wall of the drill pipe, and the scraper is scraped through the leather cup; S2. Open the proportional valve, place the two-position three-way solenoid valve A in the right position, the two-position three-way solenoid valve B in the right position, and the two-position two-way solenoid valve C in the right position. Connect the upper air port and the lower air port through the proportional valve, air pump, and connecting pipe. Adjust the opening of the proportional valve to adjust the gas flow in the passage of the lower air port, proportional valve, and upper air port to control the downward speed of the leather cup. S3, during the downward movement of the scraper, when the distance between it and the liquid surface in the drill pipe is less than the preset safety distance, the braking measures will be triggered, the proportional valve will be closed, the two-position three-way solenoid valve A will be placed in the left position, the two-position three-way solenoid valve B will be placed in the left position, and the two-position two-way solenoid valve C will be placed in the right position, blocking the air flow between the upper air port and the lower air port, and suspending it on the inner wall of the drill pipe. When the distance between it and the liquid surface in the drill pipe reaches the preset safety distance, the scraper can automatically run at S1 to restore the normal scraping state. If necessary, the position displayed by the pedometer can also be used to put in a permanent magnet to salvage the scraper from the drill pipe; S4. Every time a section of drill pipe is completed, the number of sections counted is increased by one, and the distance counted by the pedometer wheel is reset to zero. Every time a single stand (usually three sections of drill pipe) is completed, the number of sections counted will also be reset to zero, and the scraper will stay on the inner wall of the next section of drill pipe and send a signal that the shackle operation can be carried out. When the single stand above the scraper is disassembled, press the start button, run S1 for normal scraping, and enter the next cycle. When the scraper stops descending and the pedometer mileage has not reached a single stand, check whether the distance sensor is working properly. If it is normal, it means that the liquid level may be higher than the horizontal plane where the coupling is located. At this time, the shackle operation cannot be carried out to prevent mud leakage; S5. During the drilling process, the pressure sensor under the scraper will detect the changes in the air pressure at the lower air port in real time, and adjust the opening of the proportional valve in real time according to the air pressure value at the lower air port to balance the air pressure on the upper and lower sides of the scraper, preventing the lower air port from generating a large negative pressure or the scraper from being pressed into the mud by atmospheric pressure.

[0015] Scraping mud encounters obstacles: S6, close the proportional valve, put the two-position three-way solenoid valve A in the right position, the two-position three-way solenoid valve B in the right position, and the two-position two-way solenoid valve C in the right position, and keep the upper air port connected with the lower air port through the two-position three-way solenoid valve A, the air pump, and the two-position three-way solenoid valve B, and turn on the air pump to generate negative pressure under the leather cup, and push the leather cup downward through the pressure difference and the deadweight of the scraper to increase the thrust on the leather cup to release the jam; after the jam is released, turn off the air pump, open the proportional valve, and run S1 to perform normal scraping; if the jam cannot be released through the above operations, enter S7; S7, keep the proportional valve closed, put the two-position three-way solenoid valve A in the right position, the two-position three-way solenoid valve B in the left position, and the two-position two-way solenoid valve C in the right position, connect the upper air port to the air storage chamber through the two-position three-way solenoid valve A, the air pump, and the two-position three-way solenoid valve B, turn on the air pump, and pressurize the gas in the air storage chamber; S8. After the pressurization is completed, the two-position two-way solenoid valve C is placed in the left position, and the air storage chamber is connected to the pneumatic vibrator through the two-position three-way solenoid valve C. The pneumatic vibrator is driven by the air pump and the gas in the air storage chamber to drive the entire scraper to vibrate, so that the static friction is changed into dynamic friction, thereby achieving the purpose of unblocking; S9, repeat the process of S5 and S7 several times to release the jam by means of vibration; after the jam is released, run S1 to scrape the mud normally.

[0016] Downward speed or emergency: S10, close the proportional valve, place the two-position three-way solenoid valve A in the left position, place the two-position three-way solenoid valve B in the left position, and place the two-position two-way solenoid valve C in the right position, blocking the air flow between the upper air port and the lower air port, and preventing the scraper from continuing to move downward; S11. If an emergency occurs and the scraper loses control and moves downward, the scraper will float on the mud and will not sink due to the presence of the air storage chamber. According to the position displayed by the pedometer, you can put in a permanent magnet to remove the scraper from the drill pipe (refer to the attached figure for the above steps). Figure 7-8 ).

[0017] The beneficial effects of the present invention are: The drill pipe inner wall scraper can scrape the mud on the inner wall of the drill pipe through the leather cup. The leather cup, a flexible structure, contacts the inner wall of the drill pipe. The scraper can fit the inner wall of the drill pipe well, effectively deal with the diameter change of the inner wall of the drill pipe, and provide a more stable cleaning effect. At the same time, the laser rangefinder sensor at the bottom of the scraper can detect the liquid level change in real time and issue an alarm when necessary to predict the possible bottom hole overflow. It solves the problems of the existing scraper blade not being able to fit the inner wall of the drill pipe well and being unable to warn of overflow. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2is a cross-sectional schematic diagram of the present invention; Figure 3 is an exploded schematic diagram of the present invention; Figure 4 It is a structural schematic diagram of a pedometer of the present invention; Figure 5 yes Figure 1 The enlarged schematic diagram of point A in the middle; Figure 6 It is a structural schematic diagram of the pedometer wheel of the present invention; Figure 7 It is a connection schematic diagram of the gas circuit of the present invention; Figure 8 It is the air pressure principle diagram of the present invention.

[0019] In the figure: 1. shell, 2. leather cup, 3. two-position three-way solenoid valve A, 4. two-position three-way solenoid valve B, 5. two-position three-way solenoid valve C, 6. proportional valve, 7. pneumatic vibrator, 8. air storage chamber, 9. battery pack, 10. air pump, 11. bracket, 12. pedometer base, 13. pedometer wheel bracket, 14. pedometer wheel, 15. torsion spring, 16. upper air port, 17. lower air port, 18. magnet, 19. Hall sensor, 20. laser ranging sensor and pressure sensor, 21. sensor bracket, 22. sealing ring, 23. connecting block. DETAILED DESCRIPTION

[0020] The drill pipe inner wall scraper includes a shell 1, a leather cup 2, a two-position three-way solenoid valve A3, a two-position three-way solenoid valve B4, a two-position three-way solenoid valve C5, a proportional valve 6, a pneumatic vibrator 7, an air storage chamber 8, a battery pack 9 and an air pump 10. The shell 1 is cylindrical, and a leather cup 2 is arranged on the circumferential surface of the shell 1, so that the leather cup 2 is pressed against the inner wall of the drill pipe, so that the leather cup 2 and the inner wall of the drill pipe are sealed. During the downward movement of the leather cup 2, the leather cup 2 squeezes the mud on the inner wall of the drill pipe to move downward, so that the mud on the inner wall of the drill pipe is scraped off by the leather cup 2 during the downward movement of the leather cup 2. A two-position three-way solenoid valve A3, a two-position three-way solenoid valve B4, a two-position three-way solenoid valve C5 and a proportional valve 6 are sequentially mounted on the inner wall of the housing 1 from top to bottom through a bracket 11. A pneumatic vibrator 7 is arranged in the housing 1 below the proportional valve 6, and an air storage chamber 8 is fixedly mounted on the bottom port of the housing 1. A battery pack 9 is arranged above the housing 1, and the battery pack 9 is connected to an air pump 10. The battery pack 9 includes a protective shell and a plurality of battery cells for energy storage. The battery pack 9 supplies power to the air pump 10, the two-position three-way solenoid valve A3, the two-position three-way solenoid valve B4, the two-position three-way solenoid valve C5 and the proportional valve 6 through the electric energy stored in the battery cells. The air pump 10 is used to adjust the air pressure above and below the leather cup 2 by suction and exhaust, so that a pressure difference is formed between the upper and lower parts of the leather cup 2, thereby accelerating the downward movement of the leather cup 2 or slowing down the downward movement of the leather cup 2 under the action of the pressure difference. For example, the air pump 10 sucks air from the lower part of the leather cup 2 and exhausts air from the upper part of the leather cup 2. At this time, the air pressure above the leather cup 2 is greater than the air pressure below the leather cup 2. Under the action of the pressure difference, the leather cup 2 is pushed downward quickly. At the same time, when the downward movement of the leather cup 2 is blocked (the leather cup 2 encounters firmly attached mud When the mud is not easy to scrape off), the downward thrust of the leather cup 2 is increased by the pressure difference and the deadweight, so that the leather cup 2 is easy to unblock and continue to scrape the mud on the inner wall of the drill pipe downward; the air pump 10 sucks air from the top of the leather cup 2 and exhausts air from the bottom of the leather cup 2. At this time, the air pressure below the leather cup 2 is greater than the air pressure above the leather cup 2. Under the action of the pressure difference, an upward thrust is formed on the leather cup 2, which is opposite to the direction of gravity, so that it and gravity cancel each other out, thereby reducing the downward thrust of the leather cup 2 and slowing down the downward speed of the leather cup 2. The function of the pneumatic vibrator 7 is that when the air pump 10 drives the pneumatic vibrator 7 to vibrate through the delivered gas, the vibration of the pneumatic vibrator 7 drives the leather cup 2 to vibrate, so that the leather cup 2 continuously impacts the firmly attached mud through vibration, thereby scraping off the firmly attached mud and further ensuring the scraping mud effect. The function of the air storage chamber 8 is to store gas. The gas pumped by the air pump 10 is stored in the air storage chamber 8 to make up for the possible situation that the air pump 10 does not supply enough gas to the vibrator in a short period of time. At the same time, when special circumstances occur, the air storage chamber 8 can provide buoyancy to make the scraper float on the mud to prevent the scraper from sinking into the mud; at the same time, the two-position three-way solenoid valve A3, the two-position three-way solenoid valve B4, the two-position three-way solenoid valve C5 and the proportional valve 6 can control the flow direction of the gas, such as controlling the gas flow to the pneumatic vibrator 7 to drive the pneumatic vibrator 7 to vibrate.

[0021] A pedometer is provided on the top of the battery pack 9 to measure the running distance of the scraper in the drill rod by the pedometer, thereby judging the position of the scraper in the drill rod by the running distance of the scraper in the drill rod and positioning the scraper; at the same time, by measuring the downward distance, the downward speed is calculated, and the downward speed is used to judge whether the leather cup 2 is obstructed in the process of scraping mud: when the downward speed of the scraper fluctuates within a preset range, the scraping is normal; when the downward speed of the scraper is less than the preset threshold, the scraping is obstructed; when the downward speed of the scraper is greater than the preset threshold, the scraping is too fast or an emergency occurs.

[0022] The pedometer includes a pedometer base 12, a pedometer wheel bracket 13 and a pedometer wheel 14. The pedometer wheel bracket 13 is symmetrically installed on the pedometer base 12 through a pin shaft, and the pedometer wheel 14 is movably installed on the top end of the pedometer wheel bracket 13. By counting the number of rotations of the pedometer wheel 14 and the downward distance of the pedometer wheel 14, the downward distance of the scraper in the drill pipe can be counted, and the scraper can be positioned. For example, when the scraper encounters firmly attached mud stuck in the drill pipe, the downward distance measured by the pedometer wheel 14 can be used to judge the position where the scraper encounters obstruction in the drill pipe.

[0023] A torsion spring 15 is provided on the pedometer base 12, which can apply a thrust to the pedometer wheel bracket 13. The elastic force applied by the torsion spring 15 to the pedometer wheel bracket 13 applies a pressure to the pedometer wheel 14, squeezing the pedometer wheel 14 against the inner wall of the drill rod, ensuring that when the scraper moves downward in the drill rod, the drill rod can drive the pedometer wheel 14 to rotate through friction, so that the pedometer wheel 14 can measure the downward distance of the scraper during the downward process.

[0024] Magnets 18 are evenly distributed on the pedometer bracket 13 and the pedometer 14 on one side of the torsion spring 15, and Hall sensors 19 are respectively arranged on the pedometer bracket 13 on one side of the pedometer 14 and the pedometer base 12 on one side of the torsion spring 15 corresponding to the magnets 18. When the scraper moves downward, it drives the pedometer 14 to rotate inside the drill rod, and the Hall sensor 19 transmits the magnetic field intensity change signal of the magnet 18 sensed during the rotation of the pedometer 14 to the processor, and the moving distance is obtained by calculating the number of rotations of the pedometer 14. When the scraper has completed a section of drill rod, a neck will appear at the connection of the drill rod, causing the pedometer wheel bracket 13 to swing inward. The Hall sensor 19 installed on the pedometer base 12 will capture the change in the magnetic field strength of the magnet 18, indicating that the scraper has completed a section of drill rod. In order to reduce the pedometer error, each time the scraper has completed a section of drill rod, it is recorded as one section, and the count of the number of rotations of the pedometer wheel 14 will be reset and restarted. In this way, it can be known which section of drill rod the scraper is in and its specific position in the section of drill rod. Whenever three sections of drill rod are completed, the scraper will stay on the inner wall of the next section of drill rod, the counted number of sections will also be reset, and a signal will be issued that the shackle operation can be carried out. After the three sections of drill rod that have been cleaned are unloaded, press the start button to continue the normal scraping operation and enter the next cycle. When the step counter shows that the scraper is at the bottom of the drill pipe and the three sections of drill pipe have not been cleaned, it indicates that the liquid level may be higher than the horizontal plane where the coupling is located. At this time, the buckling operation cannot be performed to prevent mud leakage.

[0025] During the downward movement of the scraper, when the distance between it and the liquid level in the drill pipe is less than the preset safety distance, the braking measures will be triggered to suspend it on the inner wall of the drill pipe. When the distance between it and the liquid level in the drill pipe reaches the preset safety distance, the scraper can automatically operate to resume the normal scraping state. If necessary, the permanent magnet can be inserted according to the position displayed by the pedometer to remove the scraper from the drill pipe.

[0026] A sink groove is provided at the bottom center of the pedometer base 12, and the sink groove is connected to the air pump 10. On the one hand, its purpose is to isolate the air pump from the outside through the sink groove, and then protect the air pump 10 through the pedometer base 12; on the other hand, the air pump 10 is dissipated through the pedometer base 12, and the heat generated in the process of compressing the gas by the air pump 10 is dissipated outward, so as to avoid damage caused by heat accumulation of the air pump 10.

[0027] An upper air port 16 is provided on the pedometer base 12, and a lower air port 17 is provided at the bottom of the housing 1. The lower air port 17 is connected to the upper air port 16 through a proportional valve 6 and a connecting pipe. The lower air port 17 and the upper air port 16 are connected to the air pump 10, the pneumatic vibrator 7 and the air storage chamber 8 through a two-position three-way solenoid valve A3, a two-position three-way solenoid valve B4, a two-position three-way solenoid valve C5, and a connecting pipe. Specifically, the lower air port 17 and the upper air port 16 are connected to the inlet of the air pump 10 through a two-position three-way solenoid valve A3 and a connecting pipe. The outlet of the air pump 10 is connected to the air storage chamber 8 through a two-position three-way solenoid valve B4 and a connecting pipe, and is connected to the upper air port 16 through a two-position three-way solenoid valve B4 and a connecting pipe. The air storage chamber 8 is connected to the pneumatic vibrator 7 through a two-position three-way solenoid valve C5 and a connecting pipe, and the pneumatic vibrator 7 is respectively connected to the proportional valve 6 and the upper air port 16 through a connecting pipe.

[0028] A sensor bracket 21 is installed below the air storage chamber 8, and a laser distance sensor and a pressure sensor 20 are installed on the sensor bracket 21 for detecting the change of the mud liquid level below the scraper and the air pressure at the lower air port.

[0029] The method for scraping mud from the inner wall of a drill pipe comprises the following steps: Normal scraping: The scraper is lowered into the drill pipe, and the leather cup 2 of the scraper is opened and pressed against the inner wall of the drill pipe; the proportional valve 6 is opened, and the two-position three-way solenoid valve A3, the two-position three-way solenoid valve B4, and the two-position three-way solenoid valve C5 are adjusted as follows: the lower air port 17, the two-position three-way solenoid valve A3, the air pump 10, the two-position three-way solenoid valve B4, and the upper air port 16 are adjusted to be connected in sequence, and the passage between the gas storage chamber 8 and the gas vibrator 8 is disconnected through the two-position three-way solenoid valve C5. The gas in the drill pipe below the leather cup 2 is discharged to the upper part of the leather cup 2 through the passage of the lower air port 17, the proportional valve 6, and the upper air port 16, and the passage of the lower air port 17, the two-position three-way solenoid valve A3, the air pump 10, the two-position three-way solenoid valve B4, and the upper air port 16, respectively, so that the leather cup 2 can be pushed downward under the dead weight of the scraper to scrape the mud on the inner wall of the drill pipe. By adjusting the opening of the proportional valve 6, the gas flow rate in the passage of the lower gas port 17, the proportional valve 6 and the upper gas port 16 is adjusted, thereby controlling the downward speed of the leather cup 2.

[0030] Scraping mud encounters obstacles: Close the proportional valve 6, keep the two-position three-way solenoid valve A3 and the two-position three-way solenoid valve B4 connected: adjust the lower air port 17, the two-position three-way solenoid valve A3, the air pump 10, the two-position three-way solenoid valve B4, and the upper air port 16 to be connected in sequence, and disconnect the passage between the air storage chamber 8 and the gas vibrator 8 through the two-position three-way solenoid valve C5. Turn on the air pump 10, and the gas in the drill pipe below the leather cup 2 is discharged to the top of the leather cup 2 through the lower air port 17, the two-position three-way solenoid valve A3, the air pump 10, the two-position three-way solenoid valve B4, and the upper air port 16 through the work of the air pump 10, so that negative pressure is generated below the leather cup 2, thereby pushing the leather cup 2 downward through the pressure difference and the deadweight of the scraper, increasing the thrust on the leather cup 2, and thus unblocking by increasing the thrust. After unblocking, turn off the air pump 10, open the proportional valve 6, and perform normal scraping. When the pressure difference and the deadweight of the scraper cannot unblock, enter the following steps.

[0031] Keep the proportional valve 6 closed, and make the following adjustments to the two-position three-way solenoid valve A3, the two-position three-way solenoid valve B4, and the two-position three-way solenoid valve C5: adjust the upper air port 16, the two-position three-way solenoid valve A3, the air pump 10, the two-position three-way solenoid valve B4, and the air storage chamber 8 to be connected in sequence, and disconnect the passage between the air storage chamber 8 and the gas vibrator 8. Turn on the air pump 10, and fill the air storage chamber 8 through the upper air port 16, the two-position three-way solenoid valve A3, the air pump 10, the two-position three-way solenoid valve B4, and the passage of the air storage chamber 8 to pressurize the gas in the air storage chamber 8. After the air storage chamber 8 is pressurized, the air storage chamber 8 is connected to the gas vibrator 8 through the two-position three-way solenoid valve B4, and the pneumatic vibrator 7 is driven to vibrate through the air pump 10 and the gas pressure in the air storage chamber 8, and the leather cup 2 is driven to vibrate by starting the vibrator 8. Repeat the above process several times to release the jam by vibration. After the jam is released, normal mud scraping is performed.

[0032] When descending too fast or in an emergency (e.g. when the scraper fails and cannot be stopped): Close the proportional valve 6, and make the following adjustments to the two-position three-way solenoid valve A3, the two-position three-way solenoid valve B4, and the two-position three-way solenoid valve C5: block the connection between the two-position three-way solenoid valve A3 and the upper air port, and block the connection between the two-position three-way solenoid valve B4 and the lower air port, thereby disconnecting the passage between the upper air port and the lower air port, thereby preventing the scraper from continuing to descend.

[0033] If a special situation occurs where the scraper cannot be stopped from descending, the scraper will float on the mud and will not sink due to the presence of the air storage chamber 8.

[0034] The drill pipe inner wall scraper can scrape the mud on the inner wall of the drill pipe through the leather cup. The leather cup, a flexible structure, contacts the inner wall of the drill pipe. The scraper can fit the inner wall of the drill pipe well, effectively deal with the diameter change of the inner wall of the drill pipe, and provide a more stable cleaning effect. At the same time, the laser rangefinder sensor at the bottom of the scraper can detect the liquid level change in real time and issue an alarm when necessary to predict the possible bottom hole overflow. It solves the problems of the existing scraper blade not being able to fit the inner wall of the drill pipe well and being unable to warn of overflow.

Claims

1. A drill pipe inner wall scraper, comprising a housing (1), a leather cup (2), a two-position three-way solenoid valve A (3), a two-position three-way solenoid valve B (4), a two-position three-way solenoid valve C (5), a proportional valve (6), a pneumatic vibrator (7), an air storage chamber (8), a battery pack (9) and an air pump (10), characterized in that: The shell (1) is cylindrical, and a leather cup (2) is arranged on the circumferential surface of the shell (1). A two-position three-way solenoid valve A (3), a two-position three-way solenoid valve B (4), a two-position three-way solenoid valve C (5) and a proportional valve (6) are sequentially mounted on the inner wall of the shell (1) through a bracket (11) from top to bottom. A pneumatic vibrator (7) is arranged in the shell (1) below the proportional valve (6). An air storage chamber (8) is fixedly mounted on the bottom port of the shell (1). A sensor bracket (21) is mounted at the lower part of the air storage chamber (8). The sensor bracket (21) is mounted with a laser distance sensor and a pressure sensor (20). A battery pack (9) is arranged above the shell (1), and the battery pack (9) is connected to an air pump (10).

2. A drill pipe inner wall scraper according to claim 1, characterized in that: A pedometer is provided on the top of the battery pack (9).

3. A drill pipe inner wall scraper according to claim 2, characterized in that: The pedometer comprises a pedometer base (12), a pedometer wheel bracket (13) and a pedometer wheel (14); the pedometer wheel bracket (13) is symmetrically mounted on the pedometer base (12) via a pin shaft, and the pedometer wheel (14) is movably mounted on the top end of the pedometer wheel bracket (13).

4. A drill pipe inner wall scraper according to claim 3, characterized in that: The pedometer base (12) is provided with a torsion spring (15) capable of applying a thrust to the pedometer wheel bracket (13).

5. A drill pipe inner wall scraper according to claim 3, characterized in that: A sink is provided at the bottom center of the pedometer base (12), and the sink is sleeve-connected to the air pump (10).

6. A drill pipe inner wall scraper according to claim 3, characterized in that: An upper air port (16) is provided on the pedometer base (12), and a lower air port (17) is provided on the bottom of the housing (1). The lower air port (17) is connected to the upper air port (16) via a proportional valve (6) and a connecting pipe, and the lower air port (17) and the upper air port (16) are connected to an air pump (10), a pneumatic vibrator (7) and an air storage chamber (8) via a two-position three-way solenoid valve A (3), a two-position three-way solenoid valve B (4), a two-position three-way solenoid valve C (5) and a connecting pipe.

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