A short section for preventing stuck drill bits and pumps in downhole power drilling tools

Abstract

This invention relates to the field of resource exploration technology, and more particularly to a short section for preventing stuck drill bits and pump jamming in downhole power drilling tools. It includes an upper connector; one end of the upper connector is provided with a drill pipe clip for connection to the downhole power drilling tool; the other end of the upper connector is threaded to an outer casing; the right end of the upper connector is also provided with a first S-shaped cross-section shaft; the end of the outer casing away from the upper connector is threaded to a sealing connector, which is sleeved on the outside of the transmission connector; the outer casing and the transmission connector are fixedly connected by multiple pins. This short section can simultaneously meet the needs of both composite drilling and sliding drilling conditions of downhole power drilling tools. Furthermore, when encountering complex drilling conditions, the pins can be sheared by either lifting or pump-activated pressure suppression, achieving transmission separation between the drill bit and the downhole power drilling tool; thus avoiding pressure suppression during pump-activated circulation, which is beneficial for handling complex downhole situations.

Description

Technical Field

[0001] This invention relates to the field of resource exploration technology, and in particular to a short section for preventing stuck drill bits and pumps in downhole power drilling tools. Background Technology

[0002] With the rapid development of drilling technology and the practical need for energy conservation and efficiency in the exploration and development of underground energy resources such as oil and natural gas and geothermal energy, downhole power drilling tools have become an indispensable tool in drilling operations, especially in deep wells and drilling in hard formations. High-speed mud drives the downhole power drilling tool, thereby generating high-speed rotation or impact force on the drill bit at the bottom of the well, accelerating the shearing and impact crushing of the formation rock by the drill bit, which can significantly improve the mechanical drilling rate and greatly save construction costs compared with conventional rotary drilling.

[0003] However, during actual drilling operations, the complex downhole conditions, especially when drilling exploratory wells in new blocks, often lead to a lack of relevant formation data and experience from adjacent wells for reference. This inevitably results in complex downhole accidents during drilling, such as formation collapse causing drill bit burial, wellbore narrowing, or wellbore collapse causing stuck drill bits. When accidents like drill bit burial or drill bit jamming occur, the drill bit cannot rotate normally, creating a counter-torque on downhole power tools such as the screw motor. When high-speed mud acts on the screw, the motor rotor cannot rotate normally due to the counter-torque at the drill bit, causing the screw motor to malfunction and ultimately leading to mud pump pressure buildup. Therefore, when encountering these complex downhole accidents, it is impossible to start the pump for circulation, greatly increasing the difficulty of accident handling.

[0004] Therefore, in order to solve the problem of pressure buildup when encountering stuck drill bits and other complex working conditions, which prevents the pump from being started to handle the complex issues, the inventors, combining actual field needs and years of field experience, and taking into account the different operational needs of downhole power drilling tools, have developed a short section for downhole power drilling tools to prevent stuck drill bits and pump blockage. Summary of the Invention

[0005] The purpose of this invention is to provide a short section for downhole power drilling tools to prevent stuck drill bits and pump blockage, addressing the problem of pressure buildup that prevents pump circulation when encountering stuck drill bits or other complex situations. This short section can simultaneously meet the needs of both composite drilling and sliding drilling operations. Furthermore, when encountering such complex conditions, it can shear off the pin by either lifting the drill bit or using pump circulation to prevent pressure buildup, thus separating the drill bit from the downhole power drilling tool. Pressure buildup does not occur during pump circulation, which is beneficial for handling complex downhole situations.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a short section for preventing stuck drill bits and pumps in downhole power drilling tools, including an upper connector; One end of the upper connector is provided with a drill pipe buckle for connecting to the downhole power drilling tool; The outer side of the other end of the upper connector is threaded to a housing. The right end of the upper connector is also provided with a first S-shaped cross-section shaft; The outer casing is threaded with a sealing connector at the end away from the upper connector, and the sealing connector is sleeved on the outside of the transmission connector; The outer casing and the transmission joint are fixedly connected by multiple pins; The transmission joint is provided with a second S-shaped cross-section shaft corresponding to the first S-shaped cross-section shaft at one end near the upper joint; The cross-sections of the first S-shaped shaft and the second S-shaped shaft are complementary and used to transmit torque; The transmission joint has a joint portion at the end away from the upper joint, and the joint portion of the transmission joint has a drill bit thread inside for threaded connection with the lower joint.

[0007] Furthermore, an upper single-acting assembly is also sleeved on the outer side of the first S-shaped cross-section shaft of the upper connector; The transmission joint is also fitted with a lower single-acting assembly, which is closer to the upper joint than the pin. The transmission joint is also threadedly connected to a suspension joint on its outer side, and the two ends of the suspension joint are in contact with the lower single-acting assembly and the upper single-acting assembly, respectively.

[0008] Furthermore, the outer casing has multiple pin holes on its right-side peripheral side, and the transmission connector also has pin holes of the same number and position as the pin holes on the outer casing, with the pins fixed inside the pin holes.

[0009] Furthermore, a sealing ring is also provided on the inner wall of the sealing joint.

[0010] Furthermore, the outer diameter of the connector portion of the transmission joint is the same as the outer diameter of the outer casing.

[0011] Furthermore, the transmission joint, sealing joint, suspension joint, outer shell, and upper joint are all hollow, high-strength metal round tubes.

[0012] Furthermore, the diameter of the first S-shaped cross-section shaft is smaller than the diameter of the threaded connection between the upper connector and the outer casing.

[0013] Furthermore, the length of the second S-shaped cross-section shaft is less than the length of the first S-shaped cross-section shaft.

[0014] This invention has at least the following beneficial effects: The short section of this invention can simultaneously meet the needs of both composite drilling and sliding drilling of downhole power drilling tools. At the same time, when encountering complex working conditions, the pin can be sheared by lifting or pumping to depressurize, thereby achieving transmission separation between the drill bit and the downhole power drilling tool. This avoids the situation where pressure will not occur during pump circulation, which is beneficial for handling complex downhole situations. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A schematic diagram of the tool assembly; Figure 2 These are the top and right sectional views of the connector; Figure 3 The transmission joint is shown in sectional view and left view. Figure 4 This is a perspective view of the transmission joint.

[0017] In the diagram: 1. Transmission joint; 11. Second S-shaped section shaft; 12. Drill bit buckle; 2. Sealing joint; 3. Lower single-acting assembly; 4. Suspension joint; 5. Upper single-acting assembly; 6. Housing; 7. Upper joint; 71. Drill pipe buckle; 72. First S-shaped section shaft; 8. Pin. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0019] Please see Figure 1 This invention provides a short section for preventing stuck drill bits and pumps in downhole power drilling tools.

[0020] Includes transmission joint 1, sealing joint 2, lower single-acting assembly 3, suspension joint 4, upper single-acting assembly 5, housing 6, upper joint 7, and pin 8.

[0021] The transmission joint 1, sealing joint 2, suspension joint 4, outer shell 6, and upper joint 7 are all hollow high-strength metal round tubes. The upper joint 7, outer shell 6, and sealing joint 2 are sequentially threaded from left to right, and the main body of the other components are located inside the above three components.

[0022] See Figure 2 and Figure 3The upper connector 7 has a drill pipe thread 71 machined on its left end for connecting with downhole power drilling tools such as the upper screw motor or turbine drill. The outer right end of the connector has a thread that connects with the threaded left end of the outer casing 6. The right end face is set as a first S-shaped cross-section shaft 72, the diameter of which is slightly smaller than the diameter of the threaded part on its left side.

[0023] Both ends of the outer shell 6 are machined with rectangular threads. Its left end is threaded to the right end of the upper connector 7, and multiple pin holes are circumferentially arranged at the right middle position for installing pins.

[0024] The left end of the sealing joint 2 is provided with a rectangular thread, which is threaded to the right end of the outer shell 6, and the inner wall is provided with a sealing ring (not shown in the figure) to seal the high-pressure fluid inside the outer shell 6.

[0025] See Figure 4 and Figure 5 The transmission joint 1 is a hollow tube, and its left end is set as a second S-shaped cross-section shaft 11. The cross-section of the second S-shaped cross-section shaft 11 is complementary to the cross-section of the first S-shaped cross-section shaft 72 at the right end of the joint 7. The two parts mesh with each other at two cross-sections to transmit torque, and the length of the second S-shaped cross-section shaft 11 is slightly smaller than the length of the first S-shaped cross-section shaft 72. The right end of the transmission joint 1 is a large-diameter joint with a drill bit thread 12 machined inside, which can be threaded to the lower drill bit joint. The outer diameter of the right end joint is the same as the outer diameter of the outer shell 6. The left end of the transmission joint 1 is provided with a rectangular thread on the right side of the S-shaped section. At the same time, multiple circumferentially distributed pin holes are provided on the right side of the S-shaped section on the left end of the transmission joint 1.

[0026] The upper single-acting assembly 5 and the lower single-acting assembly 3 are two sets of radial ball bearings of the same size. The upper single-acting assembly 5 is sleeved on the right end of the S-shaped section shaft of the upper connector 7, and the lower single-acting assembly 3 is set on the left end of the S-shaped section shaft of the transmission connector 1. The upper single-acting assembly 5 and the lower single-acting assembly 3 play a dual role of limiting and centering the upper connector 7 and the transmission connector 1.

[0027] The suspension joint 4 is a hollow tube with a rectangular thread inside. Its outer diameter is smaller than the inner diameter of the outer shell 6 and larger than the outer diameter of the left end tube of the transmission joint 1. The suspension joint 4 is connected to the left end of the transmission joint 1 through the rectangular thread. Its right end face contacts the left end face of the lower single-acting assembly 3, and its left end contacts the right end face of the upper single-acting assembly 5, thus limiting the two single-acting assemblies.

[0028] The pin 8 is a solid rod made of high-strength brittle material. It is evenly distributed around the pin holes on the outer shell 6 and the transmission joint 1. The pin mainly plays a limiting role for the lower single-acting assembly 3 and the transmission joint 1, preventing the transmission joint 1 from separating from the S-shaped section of the upper joint 7.

[0029] During normal operation, pin 8, the first S-shaped section shaft 72, and the second S-shaped section shaft 11 simultaneously bear torque, driving the lower drill string to rotate. When complex conditions such as stuck drill bit or burial occur when using bottom hole power drill string (at which point the drill bit cannot rotate, and therefore the outer casing 6 also cannot rotate), the upper connector 7 can be forced to rotate by starting the pump, thereby shearing pin 8; or pin 8 can be sheared by lifting the drill string (when stuck drill bit, the drill bit cannot rotate, cannot be lifted or lowered, which is equivalent to the drill bit being fixed in position; when lifting the drill string, the pin bears the upward pull). After the pin 8 is sheared, the drill string is lifted, the upper connector 7 moves upward, while the transmission connector 1 remains stationary. Thus, the upper connector 7 and the transmission connector 1 separate from the S-shaped section. At this time, when the pump is started for circulation, the upper power drill string drives the upper connector 7 to rotate, while the lower transmission connector 1 connected to the drill bit does not rotate. This can effectively avoid the situation of pressure and pump blockage caused by stuck drill or buried drill, which is conducive to pump circulation to deal with complex downhole accidents. At the same time, under the combined action of the suspension connector 4 and the sealing connector 2, the transmission connector 1 and its lower end connected to the outer end can be prevented from falling to the bottom of the well.

[0030] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.

Claims

1. A short section for preventing stuck drill bits and pumps in downhole power drilling tools, characterized in that, Including the upper connector (7); One end of the upper connector (7) is provided with a drill pipe buckle (71) for connecting to the downhole power drilling tool; The outer side of the other end of the upper connector (7) is threaded to the outer shell (6). The right end of the upper connector (7) is also provided with a first S-shaped cross-section shaft (72). The outer casing (6) is threaded with a sealing connector (2) at the end away from the upper connector (7), and the sealing connector (2) is sleeved on the outside of the transmission connector (1). The outer casing (6) and the transmission joint (1) are fixedly connected by a plurality of pins (8); The transmission joint (1) is provided with a second S-shaped cross-section shaft (11) corresponding to the first S-shaped cross-section shaft (72) at one end near the upper joint (7). The cross sections of the first S-shaped shaft (72) and the second S-shaped shaft (11) are complementary and are used to transmit torque; The transmission joint (1) has a joint part at one end away from the upper joint (7), and the joint part of the transmission joint (1) has a drill bit buckle (12) inside for threaded connection with the lower joint. The upper single-acting assembly (5) is also sleeved on the outside of the first S-shaped section shaft (72) of the upper connector (7). The transmission joint (1) is also sleeved with a lower single-acting assembly (3), which is closer to the upper joint (7) than the pin (8); the upper single-acting assembly (5) and the lower single-acting assembly (3) are two sets of radial ball bearings of the same size. The transmission joint (1) is also threadedly connected to a suspension joint (4), and the two ends of the suspension joint (4) are in contact with the lower single-acting assembly (3) and the upper single-acting assembly (5) respectively.

2. The anti-sticking pump sub for downhole power drilling tools according to claim 1, characterized in that, The outer casing (6) has a plurality of pin holes on its circumferential side at the middle right position. The transmission joint (1) also has pin holes of the same number and position as the pin holes on the outer casing (6). The pins (8) are fixed inside the pin holes.

3. The anti-sticking pump sub for downhole power drilling tools according to claim 1, characterized in that, The inner wall of the sealing joint (2) is also provided with a sealing ring.

4. The anti-sticking pump sub for downhole power drilling tools according to claim 1, characterized in that, The outer diameter of the connector portion of the transmission connector (1) is the same as the outer diameter of the outer shell (6).

5. The anti-sticking pump sub for downhole power drilling tools according to claim 1, characterized in that, The transmission joint (1), sealing joint (2), suspension joint (4), outer shell (6), and upper joint (7) are all hollow high-strength metal round tubes.

6. The anti-sticking pump sub for downhole power drilling tools according to claim 1, characterized in that, The diameter of the first S-shaped section shaft (72) is smaller than the diameter of the threaded connection between the upper connector (7) and the outer shell (6).

7. The anti-sticking pump sub for downhole power drilling tools according to claim 1, characterized in that, The length of the second S-shaped cross-section shaft (11) is less than the length of the first S-shaped cross-section shaft (72).

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