Drifting centralizer and using method

Abstract

The invention relates to the field of petroleum and natural gas drilling engineering, in particular to a drifting centralizer and a using method.The drifting centralizer comprises a connecting cylinder, the connecting cylinder is provided with an axially-through connecting hole, the connecting hole is used for allowing a drill rod to penetrate through, and the connecting cylinder can be detachably connected with the drill rod; a plurality of centralizing strips are arranged along the outer wall of the connecting cylinder in an extending mode, a through groove is formed between every two adjacent centralizing strips, the through grooves penetrate through spaces at the two ends of the connecting cylinder, and cutting parts used for cutting falling blocks in a well are arranged at the longitudinal ends of the centralizing strips. The arranged centralizing strips can abut against the well wall of the well, so that the effect of centralizing the drill bit is achieved; when the cutting part encounters falling blocks, the falling blocks can be crushed into disintegrating slag or silt, and the silt and the disintegrating slag are transferred to the rear end of the advancing direction of the drifting centralizer through the through groove, so that drill jamming during drifting is avoided, the drifting time is shortened, and the drifting efficiency is improved; the invention further relates to a using method of the drifting centralizer.

Description

Technical Field

[0001] The invention relates to the field of oil and gas drilling engineering, and in particular to a well centralizer and a use method thereof. Background Art

[0002] In oil and gas drilling projects, drill pipes are important tools for clearing collection pipelines. For collection wells located in hilly areas, the total thickness of high-quality reservoirs underground is 30m-40m. In addition, due to the complex topography of hilly areas, the length and horizontal offset distance of the horizontal section of the collection well are relatively large, and the well trajectory may even be severely tilted or tilted upward. In order to achieve a breakthrough in production capacity, it is necessary to perform bridge plug segmented fracturing on the high-quality reservoirs, and a centralizer is required to clear the well before lowering the casing.

[0003] However, due to the changeable well paths in hilly areas, it is necessary to use double or triple stabilizers in combination with drill pipes during well cleaning, and to set adjacent stabilizers at intervals to obtain better well cleaning effects. If the well wall becomes unstable when the drill pipe is being drilled in or taken out, larger pieces will accumulate between adjacent stabilizers, and it is difficult for existing stabilizers to destroy the pieces, which will cause the drill to get stuck and form downhole faults.

[0004] Therefore, a technical solution is urgently needed to solve the technical problem that the existing centralizer is prone to falling off and jamming the drill during well drilling operations. Summary of the invention

[0005] The purpose of the present invention is to provide a well-drilling centralizer and a use method thereof in view of the technical problem that the existing centralizer is prone to block loss and drill bit jam during well-drilling operation.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: A well straightening device comprises a connecting tube, the connecting tube is provided with an axially through connecting hole, the connecting hole is used to pass a drill pipe, and the connecting tube can be detachably connected to the drill pipe; a plurality of straightening bars are extended along the outer wall of the connecting tube, through grooves are formed between adjacent straightening bars, the through grooves pass through the space at both ends of the connecting tube, and the longitudinal ends of the straightening bars are provided with cutting portions for cutting blocks dropped in the well.

[0007] The invention relates to a well straightening device, wherein a through connection hole is provided on a connection tube, and after a drill rod passes through the connection hole, the connection tube can be fixed on the drill rod through the connection hole, so that the connection tube rotates with the drill rod; a plurality of straightening bars are provided on the outer wall of the connection tube, and through grooves are formed between adjacent straightening bars. When the drill rod is drilling, the straightening bars abut against the wellbore, thereby straightening the travel path of the drill rod, and the through grooves can discharge fine materials such as mud and sand from the front end of the travel direction of the drill rod to the rear end of the travel direction, thereby avoiding difficulty in well clearing caused by siltation; a cutting portion is provided at the longitudinal end of the straightening bar, and the cutting portion rotates with the drill rod. The rod rotates, and when the cutting part that moves at high speed encounters a falling block, the cutting part contacts the falling block and cuts and crushes the falling block into small blocks or mud and sand that can pass through the through groove, thereby eliminating the falling blocks on the travel path of the drill rod, thereby avoiding drill jamming. A well straightening device of the present invention can straighten the travel path of the drill rod when the drill rod is performing a well straightening operation. When encountering a falling block, the cutting part that rotates with the drill rod hits and cuts the falling block, turning the falling block into small blocks or mud and sand, and can transfer the small blocks and mud and sand to the rear end of the travel direction of the drill rod through the through groove, thereby eliminating the falling blocks and avoiding mud and sand accumulation, thereby avoiding the occurrence of drill jamming.

[0008] As a preferred embodiment of the present invention, the cutting portion includes a cutting surface arranged at the end of the straightening bar and a cutting member arranged on the cutting surface, the cutting surface is away from the top surface of the connecting tube, and the cutting surface is arranged at an obtuse angle with the outer wall of the connecting tube. The cutting portion is composed of the cutting surface and the cutting member. When rotating at a high speed, both the cutting surface and the cutting member can cut the falling block. The straightening bar is away from the top surface of the connecting tube, and a space is reserved on the connecting tube for easy operation, so that the connecting tube is easy to install and disassemble on the drill pipe, which improves the usability of the well straightening device; the cutting surface is arranged at an obtuse angle with the outer wall of the connecting tube, so that the contact area between the cutting surface and the cutting member and the falling block is larger, and when cutting the falling block, the cutting efficiency of the falling block can be increased.

[0009] As a preferred embodiment of the present invention, the cutting member includes a plurality of cutting columns, and the plurality of cutting columns are arranged in an array on the cutting surface, and the cutting surface is set as a plane or an arc-shaped convex surface. The cutting member is composed of a plurality of cutting columns arranged in an array, and the cutting columns are arranged in an array on the cutting surface, and intervals are set between adjacent cutting columns. When the falling block contacts the cutting column moving at a high speed, the falling block is cut and crushed into fragments and mud by the cutting column; the cutting surface is a plane, so that the falling block can be hit by multiple cutting columns at the same time, thereby accelerating the cutting efficiency of the falling block; the cutting surface is an arc-shaped convex surface, and the cutting columns arranged on the arc-shaped convex surface make the area of ​​single contact between the cutting column and the falling block smaller, and the cutting column has stronger damage to the falling block; the spacing between the cutting columns needs to be adjusted according to the diameter of the debris that can pass through the through slot, so that the cut debris and mud can be discharged through the through slot to the rear end of the travel direction of the well straightener.

[0010] As a preferred embodiment of the present invention, the cutting column includes a conical column or a cylindrical column. The cutting column is a conical column, which has a tip. When moving at high speed, the tip can penetrate into the falling block, making the conical column more destructive to the falling block; the cutting column is a cylindrical column, and the side of the cylindrical column hits the falling block, crushing the falling block into debris and mud, which is more conducive to discharge from the through groove; in some embodiments, the cutting column is a prism, and the prism is adjusted so that two of the edges are located on the tangent side of the connecting tube, and the edges cut the falling block by rotating the connecting tube; in some embodiments, the cutting column is pyramidal.

[0011] As a preferred solution of the present invention, the cutting column includes a first inclined column and a second inclined column, the inclination direction of the first inclined column is opposite to the inclination direction of the second inclined column, and the first inclined column and the second inclined column are arranged in sections on the cutting surface. The cutting column has at least two different setting angles on the cutting surface, and the inclination directions of the first cutting column and the second cutting column are opposite, so that the drill pipe can destroy the falling block when rotating in the forward direction and the reverse direction, and the cutting part can cut and crush the falling block in different rotation directions; generally, the angles between the first inclined column and the second inclined column and the cutting surface are equal, so that the drill pipe has considerable destructive force when rotating in the forward direction and the reverse direction; the first inclined column and the second inclined column are arranged in sections on the cutting surface, so that the probability of the falling block being hit by the same type of cutting column at the same time is greater, which can speed up the cutting speed of the falling block; in some embodiments, the first inclined column and the second inclined column are staggered on the cutting surface, or the first inclined column and the second inclined column are randomly arranged on the cutting surface; the inclination angles formed by the first inclined column and the second inclined column and the cutting surface are the same, and the inclination angle should be between 15 degrees and 60 degrees.

[0012] As a preferred solution of the present invention, the first inclined column and the second inclined column are both inclined along the tangent direction of the cutting surface; along the axial direction of the connecting tube, a number of the first inclined columns are arranged on the cutting surface to form a first inclined zone, and a number of the second inclined columns are arranged on the cutting surface to form a second inclined zone; along the circumferential direction of the connecting tube, the first inclined zone and the second inclined zone are alternately arranged on the cutting surface. The first inclined column and the second inclined column are both inclined along the tangent direction of the cutting surface, and the first inclined column and the second inclined column are both inclined along the axial direction of the connecting tube. When the cutting part rotates with the connecting tube, the first inclined column and the second inclined column can better impact and crush the falling blocks; a number of the first inclined columns are arranged on the cutting surface along the axial direction of the connecting tube to form a first inclined zone, and a number of the second inclined columns are arranged on the cutting surface along the axial direction of the connecting tube to form a second inclined zone, so that a number of cutting columns arranged in the first inclined zone or the second inclined zone can impact the falling blocks at the same time, which can enhance the cutting efficiency and accelerate the crushing of the falling blocks; the first inclined zone and the second inclined zone are alternately arranged, so that the well straightener can have a good cutting effect on the falling blocks when rotating forward and reverse.

[0013] As a preferred solution of the present invention, the top surface of the straightening bar away from the connecting tube is set as an arc surface, and the arc surface can form a line contact with the well. By arranging a plurality of straightening bars in a ring on the connecting tube, both ends of the well straightening device are constructed as an arc structure, and the arc structure makes it easier for the falling block to contact the cutting part, and the arc surface can form a line contact with the well, thereby reducing the contact area between the well straightening device and the inner wall of the well, reducing the movement friction of the well straightening device, and enabling the well straightening device to move smoothly in the well while having the function of straightening the drill pipe.

[0014] As a preferred embodiment of the present invention, the straightening bar includes a spiral rib, the through groove is configured as a spiral groove, the adjacent spiral ribs are arranged at intervals, and the outer wall of the connecting tube is configured as the groove bottom of the spiral groove. The straightening bar is a spiral rib, and the adjacent spiral ribs are arranged at intervals, so that the through groove is configured as a spiral groove. When the spiral groove rotates, debris and silt enter the spiral groove. As the well straightening device rotates, the silt and debris can be more easily discharged to the rear end of the well straightening device in the direction of travel, avoiding the accumulation of debris and silt that causes difficulty in the movement of the drill pipe, and also avoiding the accumulated debris blocking the contact between the falling block and the chip part; the adjacent straightening bars are arranged at intervals, the outer wall of the connecting tube is configured as the groove bottom of the spiral groove, the side wall of the connecting tube is smooth, and provides a more spacious space, so that the debris and silt are easier to move in the spiral groove; in some embodiments, the spiral groove is a U-shaped or V-shaped spiral groove.

[0015] As a preferred solution of the present invention, the cutting parts are provided at both ends of the straightening bar. The cutting parts are provided at both ends of the straightening bar, so that both ends of the well straightening device can cut the falling blocks; so that the well straightening device can clean the falling blocks on the travel path when the drill bit is drilling forward and backward, thereby avoiding drill jam.

[0016] A method for using a well centralizer, using the well centralizer mentioned above, comprises the following steps: S1: Install a well centralizer on the drill pipe, and firmly connect the well centralizer to the drill pipe so that the well centralizer can rotate with the drill pipe; S2: Place the drill pipe carrying the well straightener into the well; S3: Start the drill pipe to rotate clockwise, and make the drill pipe drive the drill bit to continue drilling. The well straightener rotates clockwise along with the drill pipe. When a block falls, the block on the path of the well straightener can be crushed. S4: When the centralizer is stuck by the falling block, the drill pipe torque increases, the drill pipe will release the counter-torque, and the drill pipe starts to rotate counterclockwise. The high-speed rotating well centralizer in the wellbore cuts the falling block on the drill pipe travel path counterclockwise.

[0017] The invention provides a method for using a well clearing centralizer. The well clearing centralizer is fixedly clamped on a drill pipe. When a well clearing operation is performed, the drill pipe carries the well clearing centralizer into the wellbore. During the process of drilling in or out of the drill pipe, the well clearing centralizer rotates along with the drill pipe. When a block is encountered, a cutting portion of the well clearing centralizer rotating at a high speed contacts the block to cut and crush the block. The debris of the block is discharged into the rear end of the well clearing centralizer in the travel direction through a through groove, thereby enabling the drill bit to drill in and out smoothly and avoiding drill jamming caused by the block.

[0018] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. A well straightening device of the present invention has a through connection hole provided on the connection tube, through which the drill rod passes, and the connection tube can be fixed on the drill rod through the connection hole, so that the connection tube rotates with the drill rod; a plurality of straightening bars are provided on the outer wall of the connection tube, and through grooves are formed between adjacent straightening bars. When the drill rod is drilling, the straightening bars abut against the wellbore, thereby straightening the travel path of the drill rod, and the through grooves can discharge fine materials such as mud and sand from the front end of the travel direction of the drill rod to the rear end of the travel direction, thereby avoiding the difficulty of well straightening caused by the accumulation of sand and stone; a cutting part is provided at the longitudinal end of the straightening bar, and the cutting part rotates with the movement of the drill rod. The drill pipe rotates, and when the cutting part that moves at high speed encounters a falling block, the cutting part contacts the falling block and cuts and crushes the falling block into small blocks or mud and sand that can pass through the through groove, thereby eliminating the falling blocks on the travel path of the drill pipe, thereby avoiding drill jamming. A well straightening device of the present invention can straighten the travel path of the drill pipe when the drill pipe is performing a well straightening operation. When encountering a falling block, the cutting part that rotates with the drill pipe hits and cuts the falling block, turning the falling block into small blocks or mud and sand, and can transfer the small blocks and mud and sand to the rear end of the travel direction of the drill pipe through the through groove, thereby eliminating the falling blocks and avoiding mud and sand accumulation, thereby avoiding the occurrence of drill jamming.

[0019] 2. A well straightening device of the present invention has a straightening bar that can abut against the wall of the wellbore, thereby achieving the effect of straightening the drill bit; the cutting portion arranged on the straightening bar can break the fallen blocks into debris or mud when encountering block drop, and can transfer the mud and debris to the rear end of the well straightening device in the travel direction through the through groove, thereby avoiding drill sticking during well clearing, reducing well clearing time, improving well clearing efficiency, and having good economic value and practical value.

[0020] 3. A method for using a well straightener of the present invention is as follows: the well straightener is fixedly connected to a drill pipe so that the well straightener can rotate with the drill pipe. When performing well straightening operations, the drill pipe carries the well straightener into the wellbore. When a block is encountered during the process of the drill pipe drilling in or out, the well straightener rotates at a high speed so that the cutting portion first contacts the block, so that the block is cut and crushed into debris and mud. The debris and mud are discharged to the rear end of the well straightener in the direction of travel through the barrel groove, thereby eliminating the block, allowing the drill bit to drill in and out smoothly, and avoiding the drill pipe from getting stuck in the wellbore. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of the front view structure of a well centralizer of Example 1; Figure 2 is a schematic diagram of the front view structure of a well centralizer of Example 1; Figure 3 is a schematic diagram of a top view of the structure of a well centralizer in Example 1; Figure 4 is a partial top view of the structure of the cutting portion of Example 1; Figure 5 is a partial cross-sectional structural schematic diagram of the cutting portion of Example 1; Figure 6 This is a schematic diagram of the connection structure of a well centralizer in Example 1; Figure 7 is a partial cross-sectional structural schematic diagram of the cutting portion of Example 2; Figure 8 is a schematic diagram of a partial top view of the cutting portion of Example 3; Fig. 9 is a partial cross-sectional structural schematic diagram of the cutting portion of Example 3; Fig.10 It is a structural schematic diagram of a well straightening device of Example 7.

[0022] icon: 1-connecting tube, 2-straightening bar, 3-through groove, 4-cutting part, 5-connecting hole, 41-cutting surface, 42-cutting column, 421-first inclined column, 422-second inclined column. DETAILED DESCRIPTION

[0023] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0024] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0025] Example 1 like Figure 1-Figure 6 A well straightening device shown in the figure comprises a connecting tube 1, wherein the connecting tube 1 is provided with an axially through-going connecting hole 5, wherein the connecting hole 5 is used for passing a drill pipe, and the connecting tube 1 can be detachably connected to the drill pipe; a plurality of straightening bars 2 are extended along the outer wall of the connecting tube 1, and through grooves 3 are formed between adjacent straightening bars 2, wherein the through grooves 3 pass through the space at both ends of the connecting tube 1, and a cutting portion 4 is provided at the longitudinal end of the straightening bar 2 for cutting off blocks dropped in the well.

[0026] Specifically, the cutting portion 4 is composed of a cutting surface 41 and a cutting member. The cutting surface 41 is located at the end of the straightening bar 2, so that during the drilling process, the cutting surface 41 can collide with the falling block to cut the falling block. The cutting member is arranged on the cutting surface 41, and the cutting member can collide with and crush the falling block to break the falling block into debris and mud that can pass through the through groove 3. The cutting surface 41 is arranged away from the top surface of the connecting tube 1, and an internal thread is arranged in the connecting hole 5. The connecting tube 1 is fixed to the drill rod by a threaded connection through the internal thread; the cutting surface 41 is arranged at an obtuse angle to the outer wall of the connecting tube 1, so that the cutting surface 41 and the falling block can have a larger contact area, thereby improving the cutting efficiency; a plurality of cutting surfaces 41 are arranged in a ring with the axis of the connecting tube 1 as the center, so that when the connecting tube 1 rotates, the cutting surface 41 and the cutting member can evenly cut the falling block, thereby improving the stability of cutting the falling block and avoiding drill bit jumping.

[0027] Specifically, the cutting member is a plurality of cutting columns 42 arranged in an array, the cutting columns 42 are cylinders, the cutting surface 41 is a plane, and the plurality of cylinders are arranged on the cutting surface 41 in an array-like manner; when the drill pipe carries the well straightener and rotates, the falling block can collide with the edge of the cutting surface 41, and since the edge of the cutting surface 41 has edges and corners, the edges and corners can cut the falling block; the cutting columns 42 are protrudingly arranged on the cutting surface 41, so that the cutting columns 42 can hit the falling block through its edge, so that the falling block can be crushed into debris and mud; according to the needs of use, the distance between adjacent cutting columns 42 can be adjusted to adjust the diameter of the debris passing through the through groove 3; generally, the larger the distance between the cutting columns 42, the larger the diameter of the debris will be, but the shorter the crushing time of the falling block will be, the smaller the distance between the cutting columns 42, the smaller the diameter of the debris will be, but the longer the crushing time of the falling block will be; the adjustment of the distance should also be set and matched according to the size of the through groove 3, so that the debris can pass through the through groove 3 smoothly.

[0028] Specifically, the cutting column 42 arranged on the cutting surface 41 includes a first inclined column 421 and a second inclined column 422, the first inclined column 421 forms a first angle with the cutting surface 41, the second inclined column 422 forms a second angle with the cutting surface 41, the first inclined column 421 and the second inclined column 422 are both inclined along the tangent direction of the cutting surface 41, preferably the first inclined column 421 and the second inclined column 422 are inclined toward the tangent direction of the connecting tube 1, the second angle and the first angle are both 60 degrees, and the first inclined column 421 and the second inclined column 422 are constructed to have opposite inclination directions; the first inclined area and the second inclined area are arranged in different areas, along the connecting tube In the axial direction of the tube 1, a plurality of first inclined columns 421 are arranged to form a first inclined zone, and a plurality of second inclined columns 422 are arranged to form a second inclined zone; along the circumferential direction of the connecting tube 1, the first inclined zones and the second inclined zones are alternately arranged on the cutting surface 41; when the falling block contacts the cutting surface 41, the first inclined columns 421 or the second inclined columns 422 located in the same area can hit the falling block at the same time, so that the area of ​​the falling block cut at a single time is larger, thereby accelerating the cutting speed of the falling block; the inclined cutting column 42 allows the edge of the cutting column 42 to hit the falling block with a smaller area, thereby improving the destructive ability of the falling block and strengthening the crushing effect of the falling block.

[0029] Specifically, the top surface of the straightening strip 2 away from the connecting tube 1 is set as an arc surface, and the highest point of the arc surface is located in the middle of the straightening strip 2. A plurality of straightening strips 2 are arranged along the circumference of the connecting tube 1, so that both ends of the well clearing straightener are arc structures. When performing well clearing operations, only the highest point of the arc surface is in contact with the wellbore wall, so that the arc surface can form a linear contact with the wellbore, reducing the contact area between the well clearing straightener and the wellbore, so that the well clearing straightener can move smoothly in the wellbore; the arc structure can also make it easier for the falling block to contact with the cutting part 4, thereby accelerating the cutting rate of the falling block, avoiding drill sticking, and improving the well clearing efficiency.

[0030] Specifically, the straightening bar 2 is a spiral rib, which is spirally coiled on the outer wall of the connecting tube 1, and the through groove 3 is constructed as a spiral groove; when the drill pipe drives the well straightener to rotate, the debris can be discharged to the rear end of the well straightener in the travel direction through the spiral groove, so as to avoid the accumulation of debris and covering the cutting part 4. The spiral groove is more conducive to the discharge of debris; the spiral groove is a U-shaped or V-shaped spiral groove.

[0031] Specifically, four spiral ribs are provided, and four straightening bars 2 are arranged in a ring on the outer wall of the connecting tube 1 with the axis of the connecting tube 1 as the center. The spiral rib and the connecting tube 1 are an integrally formed structural component.

[0032] Specifically, cutting parts 4 are provided at both ends of the spiral rib; the cutting parts 4 provided at both ends of the spiral rib enable the well straightener to clear the fallen blocks on the travel path when drilling and withdrawing, thereby avoiding drill jamming.

[0033] Specifically, a clamping portion is provided on the outer wall of the connecting tube 1 near the end, the clamping portion is spaced apart from the straightening bar 2, and the clamping portion can be connected with the installation tool by clamping, so as to facilitate the installation and disassembly of the well straightening device.

[0034] A well straightening device of this embodiment is provided. Before use, the connecting tube 1 is assembled A well straightening device of the present invention is provided with a through connection hole 5 on the connection tube 1, and the connection hole 5 is used for the drill rod to pass through, and the connection tube 1 can be fixed on the drill rod through the connection hole 5, so that the connection tube 1 can rotate with the drill rod; a plurality of straightening bars 2 are provided on the outer wall of the connection tube 1, and through grooves 3 are formed between adjacent straightening bars 2. When the drill rod is drilling, the straightening bars 2 abut against the wellbore to straighten the travel path of the drill rod, and the through grooves 3 can discharge fine materials such as mud and sand from the front end of the travel direction of the drill rod to the rear end of the travel direction, thereby avoiding the difficulty of well straightening caused by the accumulation of sand and stone; a cutting part 4 is provided at the longitudinal end of the straightening bar 2, and the cutting part 4 is provided. The cutting part 4 rotates with the drill pipe. When encountering a falling block, the cutting part 4 moving at high speed contacts with the falling block and cuts and crushes the falling block into small blocks or mud and sand that can pass through the through groove 3, thereby eliminating the falling blocks on the travel path of the drill pipe, thereby avoiding drill jamming. A well straightening device of the present invention can straighten the travel path of the drill pipe when the drill pipe is performing a well straightening operation. When encountering a falling block, the cutting part 4 rotating with the drill pipe hits and cuts the falling block, turning the falling block into small blocks or mud and sand, and can transfer the small blocks and mud and sand to the rear end of the travel direction of the drill pipe through the through groove 3, thereby eliminating the falling blocks and avoiding mud and sand accumulation, thereby avoiding the occurrence of drill jamming.

[0035] Example 2 like Figure 7 The structure of the well centralizer is substantially the same as that of the first embodiment, but is different from the first embodiment in that the cutting surface 41 is an arc-shaped convex surface.

[0036] Specifically, a plurality of cutting columns 42 are spaced apart on the arc-shaped convex surface.

[0037] In the well straightening device of the present embodiment, the cutting surface 41 is an arcuate convex surface. When the drill pipe drives the well straightening device, the cutting column 42 arranged on the arcuate convex surface can accelerate the cutting of the fallen blocks and enable the fallen blocks to be cut more evenly.

[0038] Example 3 like Figure 8-Figure 9 The structure of a well centralizer shown is substantially the same as that of Example 1, but different from Example 1 in that the cutting column 42 is a conical column.

[0039] Specifically, the cutting column 42 is a conical column, and the tip of the conical column can be inserted into the falling block to enhance the damaging effect on the falling block.

[0040] Preferably, the cutting column 42 is a pyramid column, which is preferably a quadrangular pyramid, and two of its edges are located in the tangent direction of the cutting surface 41. When the connecting tube 1 rotates, the edges located in the tangent direction of the cutting surface 41 can cut the falling blocks.

[0041] In a well straightener of the present embodiment, the cutting column 42 is a conical column, which can more easily penetrate into the fallen block to facilitate the destruction of the fallen block; preferably, the cutting column 42 is a pyramid column, and the fallen block can be cut through the edges of the pyramid column, thereby improving the cutting efficiency of the fallen block; in some embodiments, the cutting column 42 is a pyramid.

[0042] Example 4 A well centralizer of the present invention has a structure substantially the same as that of Embodiment 1, but differs from Embodiment 1 in that the first inclined columns 421 and the second inclined columns 422 are randomly distributed on the cutting surface 41 .

[0043] Preferably, the first inclined column 421 and the second inclined column 422 are arranged at intervals on the cutting surface 41 .

[0044] In the well straightener of the present embodiment, the first inclined column 421 and the second inclined column 422 are randomly distributed on the cutting surface 41, so that the fallen blocks can randomly hit different first inclined columns 421 or second inclined columns 422, and the fallen blocks of different shapes can be quickly cut; the first inclined column 421 and the second inclined column 422 are arranged at intervals on the cutting surface 41, and when cutting the fallen blocks, the fallen blocks can be cut more evenly.

[0045] Example 5 The structure of a well centralizer in this embodiment is substantially the same as that of Embodiment 1, but different from Embodiment 1 in that the first angle and the second angle are both 30 degrees.

[0046] Preferably, the first angle and the second angle can be changed to an angle of 15 degrees to 60 degrees according to design requirements.

[0047] A well straightener of the present embodiment sets the first angle and the second angle to 30 degrees, so that the top edge of the first inclined column 421 or the second inclined column 422 can better impact the fallen blocks in different rotation directions, thereby improving the cutting efficiency of the fallen blocks. The size of the first angle and the second angle can be adjusted to 15 degrees to 60 degrees according to usage requirements.

[0048] Example 6 The structure of a well centralizer of this embodiment is substantially the same as that of embodiment 1. The difference from embodiment 1 is that adjacent spiral ribs are arranged at intervals so that the outer wall of the connecting tube 1 is constructed as the bottom of a spiral groove.

[0049] In a well straightener of this embodiment, the outer wall of the connecting tube 1 is constructed as the groove bottom of the spiral groove 3. The wider and smoother groove bottom can make the slag pass through the spiral groove more quickly.

[0050] Example 7 like Fig.10 The structure of a well centralizer shown is substantially the same as that of Example 1, but different from Example 1 in that the highest point of the arc-shaped convex surface is located at the end of the centralizing bar 2.

[0051] Specifically, a cutting surface 41 is provided at the lowest point of the arc-shaped convex surface.

[0052] A well straightener of the present embodiment is configured by placing two well straighteners against each other on a rotating rod so that the cutting surfaces 41 located on different well straighteners are respectively located at the axial ends of a connecting tube 1, and the through grooves 3 of the two well straighteners are connected, thereby enabling the well straighteners to cut off dropped blocks on both the forward and backward paths of the drill pipe.

[0053] Example 8 A method for using a well centralizer, characterized in that a well centralizer according to Embodiment 1 / Embodiment 2 / Embodiment 3 / Embodiment 4 / Embodiment 5 / Embodiment 6 is used, and the steps include: S1: Install a well centralizer on the drill pipe, and firmly connect the well centralizer to the drill pipe so that the well centralizer can rotate with the drill pipe; S2: Place the drill pipe carrying the well straightener into the well; S3: Start the drill pipe to rotate clockwise, and make the drill pipe drive the drill bit to continue drilling. The well straightener rotates clockwise along with the drill pipe. When a block falls, the block on the path of the well straightener can be crushed. S4: When the centralizer is stuck by the falling block, the drill pipe torque increases, the drill pipe will release the counter-torque, and the drill pipe starts to rotate counterclockwise. The high-speed rotating well centralizer in the wellbore cuts the falling block on the drill pipe travel path counterclockwise.

[0054] The invention provides a method for using a well clearing centralizer. The well clearing centralizer is fixedly connected to a drill pipe so that the well clearing centralizer can rotate with the drill pipe. When performing well clearing operations, the drill pipe carries the well clearing centralizer into a wellbore. When a block is encountered during the process of the drill pipe drilling in or out, the well clearing centralizer rotates at a high speed so that the cutting portion first contacts the block, so that the block is cut and crushed into debris and mud. The debris and mud are discharged to the rear end of the well clearing centralizer in the direction of travel through a barrel groove, so that the block is eliminated, the drill bit can drill in and out smoothly, and the drill pipe is prevented from getting stuck in the wellbore.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A well - straightening centralizer, characterized in that, it includes a connecting cylinder (1), the connecting cylinder (1) is provided with an axially penetrating connecting hole (5), the connecting hole (5) is used for threading a drill pipe, and the connecting cylinder (1) can be detachably connected to the drill pipe; a plurality of centralizing strips (2) are arranged along the outer wall of the connecting cylinder (1), a through - groove (3) is formed between adjacent centralizing strips (2), the through - groove (3) penetrates the space at both ends of the connecting cylinder (1), and a cutting part (4) for cutting off - blocks in the well is arranged at the longitudinal end of the centralizing strip (2).

2. The well - straightening centralizer according to claim 1, characterized in that, the cutting part (4) includes a cutting surface (41) arranged at the end of the centralizing strip (2) and a cutting member arranged on the cutting surface (41), the cutting surface (41) is away from the top surface of the connecting cylinder (1), and the cutting surface (41) is arranged at an obtuse angle with the outer wall of the connecting cylinder (1).

3. The well - straightening centralizer according to claim 2, characterized in that, the cutting member includes a plurality of cutting columns (42), the plurality of cutting columns (42) are arranged in an array on the cutting surface (41), and the cutting surface (41) is arranged as a plane or an arc - shaped convex surface.

4. The well - straightening centralizer according to claim 3, characterized in that, the cutting column (42) includes a conical column or a cylindrical column.

5. The well - straightening centralizer according to claim 3, characterized in that, the cutting column (42) includes a first inclined column (421) and a second inclined column (422), the inclination direction of the first inclined column (421) is opposite to the inclination direction of the second inclined column (422), and the first inclined column (421) and the second inclined column (422) are arranged in zones on the cutting surface (41).

6. The well - straightening centralizer according to claim 5, characterized in that, both the first inclined column (421) and the second inclined column (422) are inclined along the tangent direction of the cutting surface (41); along the axial direction of the connecting cylinder (1), a plurality of the first inclined columns (421) are arranged on the cutting surface (41) to form a first inclined zone, and a plurality of the second inclined columns (422) are arranged on the cutting surface (41) to form a second inclined zone; along the circumferential direction of the connecting cylinder (1), the first inclined zone and the second inclined zone are alternately arranged on the cutting surface (41).

7. The well - straightening centralizer according to claim 1, characterized in that, the top surface of the centralizing strip (2) away from the connecting cylinder (1) is arranged as an arc - shaped surface, and the arc - shaped surface can form a line contact with the wellbore.

8. The well - straightening centralizer according to claim 1, characterized in that, the centralizing strip (2) includes a spiral rib, the through - groove (3) is configured as a spiral groove, adjacent spiral ribs are arranged at intervals, and the outer wall of the connecting cylinder (1) is configured as the bottom of the spiral groove.

9. The well - straightening centralizer according to any one of claim 1, characterized in that, the cutting part (4) is arranged at both ends of the centralizing strip (2).

10. A method for using a hole opener centralizer, characterized in that, using a hole opener centralizer according to claim 9, the steps include: S1: Thread the hole opener centralizer on the drill pipe and firmly connect the hole opener centralizer to the drill pipe so that the hole opener centralizer can rotate with the drill pipe; S2: Place the drill pipe carrying the hole opener centralizer into the wellbore; S3: Start the drill pipe to rotate clockwise, and make the drill pipe drive the drill bit to continuously drill. The hole opener centralizer rotates clockwise with the drill pipe. When encountering a fallen block, it can break the fallen block on the traveling path of the hole opener centralizer; S4: When the centralizer is stuck by a fallen block, the torque of the drill pipe will increase accordingly, the drill pipe will release the reverse torque, and the drill pipe will start to rotate counterclockwise. The hole opener centralizer rotating at high speed in the wellbore will perform counterclockwise cutting on the fallen block on the traveling path of the drill pipe.

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