Coal field well drilling device capable of preventing drill bit from being stuck

Abstract

The coal field well drilling device comprises a drill rod, a drill collar and the drill bit from top to bottom, a main cleaning mechanism is arranged above the drill collar, and a plurality of auxiliary cleaning mechanisms are arranged in the length direction of the drill rod; the main cleaning mechanism comprises a first cover body and a plurality of lower nozzles and upper nozzles in the first cover body, the lower nozzles are uniformly distributed at the bottom of the first cover body in the circumferential direction of the first cover body, and nozzles of the lower nozzles penetrate out of the bottom surface of the first cover body and point to the drill bit; the upper sprayers are uniformly distributed at the top of the first cover body in the circumferential direction of the first cover body, and nozzles of the upper sprayers penetrate out of the top surface of the first cover body and point to the ground; the upper spray head and the lower spray head can jet high-pressure water flow outwards to impact solids around the drilling device, so that underground fluid can form turbulent flow, and drilling fluid is promoted to lead the solids to return to the ground; the secondary cleaning mechanism comprises a second cover body, a water storage bag in the second cover body and a plurality of water spraying heads, and the water spraying heads penetrate out of the top surface of the second cover body and point to the ground; the sprinkler head is connected with the water storage bag.

Description

Technical Field

[0001] The invention belongs to the technical field of coalfield drilling, and in particular relates to a coalfield drilling device capable of preventing a drill bit from getting stuck. Background Art

[0002] Drilling is a crucial and crucial process in coal mining. Drilling underground allows for various surveys and explorations of coal seams and strata, as well as field sampling. Core samples are then returned to surface laboratories for testing of various physical and chemical properties of the coal seams and strata. In the fields of coalbed methane (CBM) and oil and gas extraction, drilling underground for production wells, monitoring wells, and other functional wells is a common practice. During the drilling process, the drilling fluid may not be able to effectively and promptly remove the coal seam or stratum fragments drilled through by the drill bit due to factors such as the formulation or flow rate of the drilling fluid. Large rock blocks may also be drilled out, or the unique properties of underground coal formations may result in a high concentration of powdered solids such as pulverized coal dust and rock fragments, preventing the drilling fluid from promptly removing the drilled rock blocks. All of these factors can lead to a stuck drill bit or drill pipe. Once a stuck drill bit occurs, the drill needs to be shut down and specialized equipment must be used to determine the cause of the sticking. Then, targeted equipment can be selected to resolve the cause. Preventing stuck drill bits is a challenge facing those skilled in the art. Summary of the Invention

[0003] In response to the above problems, the present invention provides a coalfield drilling device for preventing drill bit sticking, which comprises, from top to bottom, a drill pipe, a drill collar, and a drill bit. A main cleaning mechanism is provided above the drill collar, and a plurality of secondary cleaning mechanisms are provided along the length direction of the drill pipe. The main cleaning mechanism includes a first housing and several lower and upper nozzles inside. The lower and upper nozzles are evenly distributed along the circumference of the first housing. The nozzles of the lower nozzles pass through the bottom surface of the first housing and point to the drill bit; the nozzles of the upper nozzles pass through the top surface of the first housing and point to the ground. Both the upper and lower nozzles can spray high-pressure water outward to impact the solids around the drilling device, which is conducive to forming turbulent flow of the downhole fluid and promoting the drilling fluid to carry the solids back to the ground. The cleaning mechanism includes a second cover body, an internal water storage bag and several water spray heads. The water storage bag is made of flexible material and can extend inside the second cover body after storing water. The nozzle of the water spray head passes through the top surface of the second cover body and points to the ground. The water spray head is connected to the water storage bag. The water storage bag is connected to the upper spray head and the lower spray head through a connecting pipe.

[0004] Optionally, the first cover body is annular, and the top of the drill collar supports and is connected to the first cover body, so that the first cover body can rotate together with the drill collar; The interior of the first cover body is hollow and is used to accommodate an upper nozzle and a lower nozzle. The lower nozzle is fixedly connected to the bottom surface of the first cover body, and the upper nozzle is fixedly connected to the top surface of the first cover body. The upper and lower nozzles are staggered, that is, the middle between two adjacent lower nozzles corresponds to an upper nozzle. The cleaning mechanism above the first cover body is connected to the interior of the first cover body through at least one connecting pipe to provide clean water for the upper and lower nozzles.

[0005] Further optionally, the inner side surface of the first cover body is detachably connected to the side surface of the bottom of the drill pipe, and the bottom surface of the first cover body is detachably connected to the top surface of the drill collar; The longitudinal section of the first cover body is semicircular or fan-shaped with a central angle greater than 180°, that is, the top and bottom surfaces of the first cover body are both arc-shaped, which is conducive to the drilling fluid carrying solids to pass through the first cover body smoothly and reduces the probability of the first cover body intercepting solids.

[0006] Further optionally, the lower nozzle is directed toward the top of the concave lines on the surface of the drill bit, so as to facilitate timely removal of solid rock debris inside the drill bit lines.

[0007] Optionally, the second cover body is in a circular ring shape, and the inner side surface of the second cover body is detachably connected to the side surface of the drill rod, so that the second cover body can rotate with the drill rod; the interior of the second cover body is hollow, for accommodating a water spray head and a water storage bag, and the water spray head is fixedly connected to the top surface of the second cover body; the water storage bag is made of rubber, and the water storage bag is connected to the water spray head in the same second cover body through a water pipe.

[0008] Preferably, two water spray heads are provided in the second cover body, and the two water spray heads are respectively provided on opposite sides of the second cover body, that is, the line connecting the two water spray heads is a diameter of the second cover body, so that when the second cover body rotates with the drill pipe, the two water spray heads can perform more comprehensive spraying to remove sand and slag from the space in the well above it.

[0009] Further optionally, when there are two oppositely arranged water spray heads in the second cover body, there are two water storage bags in the second cover body, the water storage bags are correspondingly connected to the water spray heads, and each water storage bag covers nearly half of the space in the second cover body.

[0010] Further optionally, a flexible connecting tube is provided at the bottom of the water storage bag, and is connected to the top of the water storage bag of the adjacent slave cleaning mechanism below through the connecting tube, or is connected to the upper and lower nozzles in the main cleaning mechanism below through the connecting tube; A pipe cover is provided on the outside of the connecting pipe, which can cover the connecting pipe inside the pipe cover to prevent the connecting pipe from contacting the drilling fluid environment in the well. The side of the pipe cover is detachable and connected to the outer side of the drill pipe, so that the drill pipe can drive the connecting pipe and the pipe cover to rotate together. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1The present invention is a schematic structural diagram of a coalfield drilling device for preventing the drill bit from getting stuck; Figure 2 is a schematic top view of the interior of the second cover; Figure 3 It is a bottom view of the exterior of the first cover.

[0012] In the accompanying drawings, 1-drill rod, 2-drill collar, 3-drill bit, 4-first cover body, 5-second cover body, 6-upper nozzle, 7-lower nozzle, 8-water storage bag, 9-sprinkler head, 10-connecting pipe. DETAILED DESCRIPTION

[0013] This embodiment provides a coalfield drilling device that prevents the drill bit from getting stuck. Figure 1-Figure 3 As shown, from top to bottom, it includes a drill pipe 1, a drill collar 2 and a drill bit 3. A main cleaning mechanism is provided above the drill collar 2, and several secondary cleaning mechanisms are provided along the length of the drill pipe 1. They are all used to clean large rocks, coal powder, and coal gravel around the drill bit 3, drill collar 2, and drill pipe 1 that may cause a drill sticking accident. The main cleaning mechanism includes a first cover body 4 and several lower nozzles 7 and several upper nozzles 6 inside the first cover body 4. The lower nozzles 7 are evenly distributed at the bottom of the first cover body 4 along the circumference of the first cover body 4. The nozzles of the lower nozzles 7 pass through the bottom surface of the first cover body 4 and point to the drill bit 3; the upper nozzles 6 are evenly distributed at the top of the first cover body 4 along the circumference of the first cover body 4. The nozzles of the upper nozzles 6 pass through the top surface of the first cover body 4 and point to the ground; both the upper nozzles 6 and the lower nozzles 7 can impact the solids around the drilling device by spraying high-pressure water outward, which is conducive to forming turbulent flow of the downhole fluid and promoting the drilling fluid to carry the solids back to the ground; The cleaning mechanism includes a second cover body 5, a water storage bag 8 inside the second cover body 5, and several water spray heads 9. The water storage bag 8 is made of flexible material and can be extended inside the second cover body 5 after storing water; the nozzle of the water spray head 9 passes through the top surface of the second cover body 5 and points to the ground; the water spray head 9 is connected to the water storage bag 8; the water storage bag 8 is connected to the upper spray head 6 and the lower spray head 7 through a connecting pipe 10.

[0014] Taking into account that the drill bit 3 and the drill rod 1 are surrounded by a liquid environment provided by drilling fluid during drilling, and that solids are mixed in the liquid, the present invention uses a high-pressure water flow impact method to continuously or intermittently flush the area around the drill bit 3 and the drill rod 1, so that a smooth solid-liquid mixed fluid environment is maintained around the drill bit 3 and the drill rod 1. If a larger block is encountered, the block can be flushed away from the drilling device under the impact of the high-pressure water flow, closer to the inner wall of the well, to avoid the block being stuck in the drill. For powdered coal powder or rock powder, the high-pressure water flow can provide a strong driving force, and cooperate with the fracturing fluid to bring the powder out of the underground well as soon as possible to avoid buried drilling. The two covers respectively protect the internal components from being damaged by the impact of drilling fluid and rock debris.

[0015] Optionally, the first cover body 4 is annular, and the top of the drill collar 2 supports and is connected to the first cover body 4, so that the first cover body 4 can rotate together with the drill collar 2; The interior of the first cover body 4 is hollow and is used to accommodate the upper and lower nozzles. The lower nozzle is fixedly connected to the bottom surface of the first cover body 4, and the upper nozzle is fixedly connected to the top surface of the first cover body 4. The upper and lower nozzles are staggered, that is, the middle between two adjacent lower nozzles corresponds to an upper nozzle. This can minimize the space occupied by the upper and lower nozzles in the first cover body 4. The cleaning mechanism above the first cover body 4 is connected to the interior of the first cover body 4 through at least one connecting pipe 10 to provide clean water for the upper and lower nozzles.

[0016] Further optionally, the inner side of the first cover 4 is detachably connected to the side of the bottom of the drill pipe 1, and the bottom surface of the first cover 4 is detachably connected to the top surface of the drill collar 2, so as to facilitate modification of the original drilling equipment, that is, installing the first cover 4 on the drill pipe 1 and the drill collar 2; The longitudinal cross-section of the first cover 4 is semicircular or a sector with a central angle greater than 180°. That is, both the top and bottom surfaces of the first cover 4 are arc-shaped. This facilitates the smooth passage of solids carried by drilling fluid through the first cover 4, reducing the probability of solids being intercepted by the first cover 4. The first cover 4 is made of a high-strength steel material, such as stainless steel, to withstand the erosion of drilling fluid.

[0017] Further optionally, the nozzle of the lower nozzle passes through the bottom surface of the first cover body 4, and the position of the passage is sealed and blocked, and the nozzle of the upper nozzle passes through the top surface of the first cover body 4, and the position of the passage is sealed and blocked to prevent drilling fluid and rock debris from entering the interior of the first cover body 4; The lower nozzle is directed toward the top of the concave lines on the surface of the drill bit 3, so as to remove the solid rock debris inside the lines of the drill bit 3 in time.

[0018] The upper and lower nozzles are both existing high-pressure water nozzles. After the water source pipeline is connected to the nozzles, the clean water is pressurized in each nozzle and then sprayed out of the nozzle with a certain pressure. The water pressure is 5-6MPa, generally not exceeding 8MPa.

[0019] Further optionally, the top surface of the first cover body 4 is connected to two connecting pipes 10, one connecting pipe 10 is connected to several pipes in parallel and respectively connected to the corresponding upper nozzles, and the other connecting pipe 10 is connected to several pipes in parallel and respectively connected to the corresponding lower nozzles. The pipes are inside the first cover body 4 to avoid being affected by the drilling fluid and can provide high-pressure water more stably.

[0020] The present invention utilizes the characteristic that the outer diameter of the drill collar 2 is larger than the outer diameter of the drill pipe 1, and sets a first cover body 4 in the empty space above the drill collar 2. Combined with the staggered arrangement of the upper and lower nozzles, it is possible to fully utilize the space above the drill collar 2 while making the volume of the first cover body 4 as small as possible. As a specific embodiment, the upper and lower nozzles can be arranged at an angle or horizontally, with only the nozzle part passing through the first cover body 4. The nozzle can be vertically downward or tilted downward. The lower nozzle sprays high-pressure water toward the drill collar 2 and the drill bit 3, which can disperse the rock blocks or rock powder around the drill collar 2 and the drill bit 3 in advance. Since the outer diameters of the drill collar 2 and the drill bit 3 of the drilling device are the largest, this can greatly reduce the probability of drill stuck.

[0021] Furthermore, while there are many types and styles of drill bits 3, the vast majority used in coal mining and geology applications feature a variety of concave and convex structures, as well as strip-shaped recessed lines (some vertical, some curved). Newly drilled rock and the released drilling fluid first flow through the drill bit 3, where rock can easily find its way into these recessed lines, increasing the risk of drill sticking. The lower nozzle of the present invention sprays water toward the top of these recessed lines on the surface of the drill bit 3, flushing out any rock trapped within it and minimizing drill sticking at the source.

[0022] Considering that the drill pipe 1 drives the drill collar 2 and the drill bit 3 to rotate, the lower nozzle also rotates together. Under the action of centrifugal force, the water flow sprayed by the lower nozzle will be deflected to a certain extent. Therefore, according to the actual rotation speed and size of the drill bit 3, the direction of the lower nozzle nozzle can be slightly adjusted.

[0023] During rotation, the upper nozzle sprays high-pressure water upward to clear rock and other obstructing solids around the drill pipe 1 above. Although the outer diameter of the first housing 4 is slightly larger than that of the drill collar 2, it can provide high-pressure water flow directed upward and downward, preemptively clearing the first housing 4 and any obstructing solids above and below it. Therefore, the first housing 4 does not affect the upward flow of drilling fluid carrying mud, sand, and rock, but rather facilitates it.

[0024] Optionally, the second cover body 5 is in a circular shape, and the inner side surface of the second cover body 5 is detachably connected to the side surface of the drill rod 1, so that the second cover body 5 can rotate with the drill rod 1; the interior of the second cover body 5 is hollow, for accommodating a water spray head 9 and a water storage bag 8, and the water spray head 9 is fixedly connected to the top surface of the second cover body 5; the water storage bag 8 is made of rubber, and the water storage bag 8 is connected to the water spray head 9 in the same second cover body 5 through a water pipe.

[0025] Further optionally, the longitudinal cross-section of the second cover 5 is semicircular or fan-shaped with a central angle greater than 180°, i.e., the top and bottom surfaces of the second cover 5 are both arc-shaped, which facilitates the smooth passage of solids carried by the drilling fluid through the second cover 5 and reduces the probability of solids being intercepted by the second cover 5. The second cover 5 is made of a high-strength steel such as stainless steel to withstand the erosion of the drilling fluid.

[0026] Preferably, two water spray heads 9 are provided within the second housing 5. The two water spray heads 9 are located on opposite sides of the second housing 5. That is, the line connecting the two water spray heads 9 is a diameter of the second housing 5. This allows the two water spray heads 9 to more comprehensively spray the wellbore space above the second housing 5 to remove sand and slag when the second housing 5 rotates with the drill pipe 1. The remaining configuration features of the water spray heads 9 are the same as those of the upper nozzles.

[0027] Further optionally, when there are two oppositely arranged water spray heads 9 in the second cover body 5, there are two water storage bags 8 in the second cover body 5, and the water storage bags 8 are correspondingly connected to the water spray heads 9, and each water storage bag 8 covers nearly half of the space in the second cover body 5.

[0028] Further optionally, a flexible connecting tube 10 is provided at the bottom of the water storage bag 8, and is connected to the top of the water storage bag 8 of the adjacent slave cleaning mechanism below through the connecting tube 10, or is connected to the upper and lower nozzles in the main cleaning mechanism below through the connecting tube 10; A pipe cover is provided on the outside of the connecting pipe 10, which can cover the connecting pipe 10 inside the pipe cover to prevent the connecting pipe 10 from contacting the drilling fluid environment in the well. The side of the pipe cover is detachably connected to the outer side of the drill rod 1, so that the drill rod 1 can drive the connecting pipe 10 and the pipe cover to rotate together.

[0029] For drill pipe 1 components with drill collars 2 and above, since the outer diameter of the drill pipe 1 is smaller than that of the drill bit 3 and drill collar 2, the space between the drill pipe 1 and the wellbore inner wall is larger, meaning there is more room for drilling fluid to circulate, significantly reducing the chance of drill pipe sticking. However, if a thinner drill pipe 1 becomes stuck, it is more likely to break. Therefore, the present invention utilizes a high-pressure water stream sprayed upward from the water nozzle 9 of the cleaning mechanism to clean the area around the drill pipe 1. For large rock and soil blocks that may be stuck between the drill pipe 1 and the wellbore inner wall, the high-pressure water stream impacts the rock and soil blocks as they approach the drill pipe 1, breaking them up or changing their travel angle to prevent them from getting stuck.

[0030] Several secondary cleaning mechanisms, arranged from top to bottom, provide a graded water supply. The upper water reservoir 8 feeds the adjacent lower water reservoir 8 via a connecting pipe 10. Gravity forces the water downward, level by level, until it reaches the upper and lower nozzles of the primary cleaning mechanism. As the drill rod 1 rotates, the high-pressure water jets from the sprinkler head 9, the upper and lower nozzles, combined with the centrifugal force of the rotation, form a jet stream that emanates from the center, prioritizing the area surrounding the drilling rig, preventing rock blocks from approaching, and eliminating drill sticking hazards in advance, achieving a highly effective preventative measure.

Claims

1. A coalfield drilling device for preventing drill bit from sticking, comprising a drill rod, a drill collar and a drill bit in order from top to bottom, characterized in that: A main cleaning mechanism is provided above the drill collar, and several slave cleaning mechanisms are provided along the length of the drill pipe. The main cleaning mechanism includes a first housing and a plurality of lower and upper nozzles therein. The lower and upper nozzles are evenly distributed along the circumference of the first housing. The nozzles of the lower nozzles pass through the bottom surface of the first housing; the nozzles of the upper nozzles pass through the top surface of the first housing. Both the upper and lower nozzles can eject high-pressure water to impact solids around the drilling device. The cleaning mechanism includes a second cover body, an internal water storage bag and several water spray heads. The water storage bag is made of flexible material. The nozzle of the water spray head passes through the top surface of the second cover body. The water spray head is connected to the water storage bag. The water storage bag is connected to the upper spray head and the lower spray head through a connecting pipe.

2. The coalfield drilling device for preventing drill bit from sticking according to claim 1, characterized in that: The first cover is annular, and the top of the drill collar supports and is connected to the first cover so that the first cover can rotate with the drill collar; The interior of the first cover body is hollow, the lower nozzle is fixedly connected to the bottom surface of the first cover body, and the upper nozzle is fixedly connected to the top surface of the first cover body. The upper and lower nozzles are staggered, and the middle between two adjacent lower nozzles corresponds to an upper nozzle. The cleaning mechanism above the first cover body is connected to the interior of the first cover body through at least one connecting pipe to provide clean water for the upper and lower nozzles.

3. The coalfield drilling device for preventing drill bit from sticking according to claim 2, characterized in that: The inner side surface of the first cover body is detachably connected to the side surface of the bottom of the drill pipe, and the bottom surface of the first cover body is detachably connected to the top surface of the drill collar. The longitudinal section of the first cover body is semicircular or fan-shaped with a central angle greater than 180°. The top and bottom surfaces of the first cover body are both arc-shaped, which is conducive to the drilling fluid carrying solids to pass through the first cover body smoothly and reduces the probability of the first cover body intercepting solids.

4. The coalfield drilling device for preventing drill bit from sticking according to claim 2, characterized in that: The lower nozzle is directed toward the top of the concave lines on the drill bit surface, so that the solid rock debris inside the drill bit lines can be removed in time.

5. The coalfield drilling device for preventing drill bit from sticking according to claim 1, characterized in that: The second cover body is in a circular shape, and the inner side surface of the second cover body is detachably connected to the side surface of the drill rod, so that the second cover body can rotate with the drill rod; the interior of the second cover body is hollow, used to accommodate a water spray head and a water storage bag, and the water spray head is fixedly connected to the top surface of the second cover body; the water storage bag is made of rubber, and the water storage bag is connected to the water spray head in the same second cover body through a water pipe.

6. The coalfield drilling device for preventing drill bit from sticking according to claim 5, characterized in that: Two water spray heads are provided in the second cover body, and the two water spray heads are respectively provided on opposite sides of the second cover body, so that when the second cover body rotates with the drill pipe, the two water spray heads can spray the well space above it more comprehensively to remove sand and slag.

7. The coalfield drilling device for preventing drill bit from sticking according to claim 6, characterized in that: There are two water storage bags in the second cover body, and the water storage bags are correspondingly connected to the water spray heads.

8. The coalfield drilling device for preventing drill bit from sticking according to claim 5, characterized in that: The bottom of the water storage bag is provided with a flexible connecting pipe, and is connected to the top of the water storage bag of the adjacent slave cleaning mechanism below through the connecting pipe, or is connected to the upper and lower nozzles in the main cleaning mechanism below through the connecting pipe; A pipe cover is provided on the outside of the connecting pipe, which can cover the connecting pipe inside the pipe cover to prevent the connecting pipe from contacting the drilling fluid environment in the well. The side of the pipe cover is detachable and connected to the outer side of the drill pipe, so that the drill pipe can drive the connecting pipe and the pipe cover to rotate together.

Images