Casing shoe

Abstract

The present disclosure provides a casing shoe, belonging to the field of oilfield cementing operations. The casing shoe includes a hydraulic turbine assembly, a float collar assembly, and a housing, a rotating sleeve, and an eccentric rotating head that are coaxially connected in sequence from top to bottom. The housing is rotatably connected to the rotating sleeve, and the rotating sleeve is rotatably connected to the eccentric rotating head; the hydraulic turbine assembly and the float collar assembly are located inside the housing, and the float collar assembly is located above the hydraulic turbine assembly. The hydraulic turbine assembly is used to drive the rotating sleeve to rotate relative to the housing under the action of hydraulic force. A plurality of drill blocks are circumferentially spaced on the outer wall of the rotating sleeve, and the plurality of drill blocks are arranged in a spiral shape. The hydraulic turbine assembly in this casing shoe can drive the rotating sleeve to rotate, driving the plurality of drill blocks on the outer wall of the rotating sleeve to rotate spirally, enabling the plurality of drill blocks to perform rotary reaming, with a function similar to the rotary drilling of a drill bit, so as to effectively break through wellbore obstacles by force and ensure the guiding function of the casing shoe in a horizontal well.

Description

Technical Field

[0001] The present disclosure relates to the field of oilfield cementing operations, and particularly to a casing shoe. Background Art

[0002] A casing shoe is a steel short section installed at the bottom end of a casing string, which is used to facilitate the lowering of the casing and strengthen the bottom of the casing. A conventional casing shoe mainly consists of a float collar short section and a guide head, and the guide head is located at one end of the float collar short section.

[0003] In related technologies, the guide head part of a conventional casing shoe is generally processed into a hemispherical arc shape with a smooth surface, which is used to reduce the contact friction force with the wellbore wall. Especially when the casing passes through an irregular section of the wellbore wall, it is convenient to overcome the resistance in the well and can better guide the casing to be lowered smoothly.

[0004] The lowering of the casing mainly depends on the self-weight of the casing and the guidance of the casing shoe. However, due to the special wellbore trajectory of a horizontal well, during the process of running the casing, the lateral pressure of the casing on the wellbore wall is very large, which greatly increases the frictional resistance of running the casing. Once the casing encounters resistance during the lowering process, the guiding function of the conventional casing shoe fails and the casing cannot be lowered continuously. Summary of the Invention

[0005] An embodiment of the present disclosure provides a casing shoe, which can ensure the guiding function of the casing shoe in a horizontal well. The technical solution is as follows:

[0006] An embodiment of the present disclosure provides a casing shoe, which includes a hydraulic turbine assembly, a float collar assembly, and a housing, a rotating sleeve, and an eccentric rotating head that are coaxially connected in sequence from top to bottom. The housing is rotatably connected to the rotating sleeve, and the rotating sleeve is rotatably connected to the eccentric rotating head;

[0007] The hydraulic turbine assembly and the float collar assembly are located in the housing, and the float collar assembly is located above the hydraulic turbine assembly. The hydraulic turbine assembly is used to drive the rotating sleeve to rotate relative to the housing under the action of hydraulic force. A plurality of drill blocks are distributed at intervals along the circumferential direction of the outer wall of the rotating sleeve, and the plurality of drill blocks are arranged in a spiral shape.

[0008] Optionally, the hydraulic turbine assembly includes a supporting base, a turbine housing, a diverter plate, a rotating shaft, and rotating blades;

[0009] The supporting base, the turbine housing, and the diverter plate are coaxially arranged in sequence from top to bottom in the housing;

[0010] The rotating blades are fixed on the rotating shaft, and the rotating blades and the rotating shaft are located in the turbine housing. One end of the rotating shaft is rotatably inserted on the supporting base, and the other end of the rotating shaft passes through the flow dividing plate and is fixedly connected to the rotating sleeve.

[0011] Both the supporting base and the flow dividing plate are provided with first liquid channels extending along the axial direction of the housing, and the first liquid channels are communicated with the inner hole of the housing.

[0012] Optionally, at least one rotating blade is fixed on the rotating shaft. The rotating blade includes a first blade and a second blade. The outer diameter of the first blade matches the inner diameter of the housing, the outer diameter of the second blade is smaller than the inner diameter of the housing, and a counterweight plate is fixed at one end of the second blade away from the rotating shaft.

[0013] Optionally, the counterweight plate is an arc-shaped plate, and the central angle corresponding to the arc-shaped plate is 60° - 180°.

[0014] Optionally, the eccentric rotating head has a central through hole, and the rotating sleeve has a communication hole for communicating the central through hole and the first liquid channel.

[0015] Optionally, the casing shoe further includes a first fixing ring, a first positioning sleeve and a first bearing.

[0016] The rotating sleeve includes a first connecting shaft and a sleeve connected coaxially. The outer diameter of the sleeve is larger than the outer diameter of the first connecting shaft.

[0017] The first fixing ring, the first positioning sleeve and the first bearing are sleeved on the first connecting shaft from top to bottom in sequence. The first fixing ring is fixedly connected to the first connecting shaft. The first positioning sleeve is movably sleeved on the first connecting shaft and fixed at the lower end of the housing. The first bearing is clamped between the end face of the first positioning sleeve and the sleeve.

[0018] Optionally, the casing shoe further includes a second fixing ring, a second positioning sleeve and a second bearing.

[0019] The eccentric rotating head includes a second connecting shaft and a rotating head connected coaxially. The end face diameter of one end of the rotating head connected to the second connecting shaft is larger than the outer diameter of the second connecting shaft.

[0020] The second fixing ring, the second positioning sleeve and the second bearing are sleeved on the second connecting shaft from top to bottom in sequence. The second fixing ring is fixedly connected to the second connecting shaft. The second positioning sleeve is movably sleeved on the second connecting shaft and fixed at the lower end of the rotating sleeve. The second bearing is clamped between the end face of the second positioning sleeve and the rotating head.

[0021] Optionally, the casing shoe further includes a float collar assembly located inside the housing. The float collar assembly is located above the hydraulic turbine assembly. The float collar assembly includes a valve seat, a valve rod, a spring member, and a diverter base that are coaxially located inside the housing from top to bottom in sequence;

[0022] The valve seat is fixedly connected to the housing. One end of the valve seat is fixedly connected to the diverter base. The valve seat and the diverter base form a second liquid passage extending along the axial direction of the housing. The second liquid passage communicates with the inner hole of the housing;

[0023] The valve rod is located inside the second liquid passage. One end of the valve rod has a blocking portion. The spring member is sleeved outside the valve rod, and the spring member is clamped between the blocking portion and the diverter base. The valve rod is configured to block the second liquid passage under the elastic force of the spring member and disconnect the communication between the second liquid passage and the inner hole of the housing.

[0024] Optionally, the casing shoe further includes a well shut-off assembly located inside the housing. The well shut-off assembly is located above the float collar assembly. The well shut-off assembly includes a fixed seat and a sliding sleeve,

[0025] The fixed seat is fixedly connected to the housing. The fixed seat is a cylindrical structure with one end open and the other end closed. At least one liquid flow hole is provided on the side wall of the fixed seat. The at least one liquid flow hole is used to communicate the inside of the fixed seat with the inner hole of the housing;

[0026] The sliding sleeve is located inside the fixed seat. The sliding sleeve is configured to slidably move from a first position to a second position operably. When the sliding sleeve is located at the first position, the at least one liquid flow hole communicates the inside of the fixed seat with the inner hole of the housing. When the sliding sleeve is located at the second position, the sliding sleeve blocks the at least one liquid flow hole to disconnect the communication between the inside of the fixed seat and the inner hole of the housing.

[0027] Optionally, the sliding sleeve is a cylinder with a flange plate at one end. The diameter of the flange plate is larger than the inner diameter of the fixed seat. The other end of the sliding sleeve is located inside the fixed seat.

[0028] The beneficial effects brought by the technical solution provided by the embodiments of the present disclosure are:

[0029] By providing a casing shoe, the casing shoe includes an eccentric rotating head. When the casing is lowered into the deflection section and the horizontal section of the horizontal well, due to the eccentric setting of the head of the eccentric rotating head, the unbalanced force when encountering resistance can be achieved. The eccentric rotating head will continue to rotate in the direction of the combined force of the resistance it receives and guide the pipe string to pass through the high resistance area and continue to go deep into the bottom of the well, overcoming obstacles, and play a guiding role. At the same time, the casing shoe is also additionally provided with a rotating sleeve and a hydraulic turbine assembly. When the casing string encounters a jam or a necking point during the lowering process, and the eccentric rotating head cannot pass the obstacle, the hydraulic turbine assembly can further drive the rotating sleeve to rotate, driving the multiple drill blocks on the outer wall of the rotating sleeve to spirally rotate. Multiple drill blocks can be rotated to drill holes, and the function is similar to the rotary drilling of the drill bit, so that the wellbore obstacles can be effectively removed by force, ensuring the guiding function of the casing shoe in the horizontal well. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] Figure 1 is a half-section view of a casing shoe provided by an embodiment of the present disclosure;

[0032] Figure 2 is a half-section view of a hydraulic turbine assembly provided by an embodiment of the present disclosure;

[0033] Figure 3 is a half-section view of a partial structure of a casing shoe provided by an embodiment of the present disclosure;

[0034] Figure 4 It is a half-section view of a floating collar assembly provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0035] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0036] Figure 1 is a half-section view of a casing shoe provided by an embodiment of the present disclosure, such as Figure 1 As shown, the casing shoe 100 includes a hydraulic turbine assembly 10, a floating collar assembly 70, and a housing 20, a rotating sleeve 30, and an eccentric rotating head 40 coaxially connected from top to bottom. The housing 20 and the rotating sleeve 30, and the rotating sleeve 30 and the eccentric rotating head 40 are all rotatably connected.

[0037] The water turbine assembly 10 and the floating collar assembly 70 are located in the housing 20, and the floating collar assembly 70 is located above the water turbine assembly 10. The water turbine assembly 10 is used to drive the rotating sleeve 30 to rotate relative to the housing 20 under the action of water. A plurality of drill blocks 31 are distributed on the outer wall of the rotating sleeve 30 along the circumference of the rotating sleeve 30, and the plurality of drill blocks 31 are arranged in a spiral shape.

[0038] The disclosed embodiment provides a casing shoe, which includes an eccentric rotating head. When the casing is lowered into the deflection section and the horizontal section of the horizontal well, the eccentric rotating head has an eccentric setting, so that the force applied to it when encountering resistance can be unbalanced. The eccentric rotating head will continue to rotate in the direction of the combined force of the resistance it receives and guide the pipe string to pass through the high resistance area and continue to go deep into the bottom of the well, overcoming obstacles, and playing a guiding role. At the same time, the casing shoe is also provided with a rotating sleeve and a hydraulic turbine assembly. When the casing string encounters a jam or a neck during the lowering process, and the eccentric rotating head cannot pass the obstacle, the hydraulic turbine assembly can further drive the rotating sleeve to rotate, driving the multiple drill blocks on the outer wall of the rotating sleeve to rotate spirally. The multiple drill blocks can be rotated to drill holes, and the function is similar to the rotary drilling of the drill bit, so that the wellbore obstacles can be effectively removed by force, and the guiding function of the casing shoe in the horizontal well can be ensured.

[0039] Optionally, the plurality of drill blocks 31 are all made of tungsten carbide hard alloy material to ensure structural strength and toughness, and the plurality of drill blocks 31 are welded and fixed on the outer wall of the rotating sleeve 30 to ensure connection strength with the rotating sleeve 30 .

[0040] Figure 2 is a half-section view of a hydraulic turbine assembly provided by an embodiment of the present disclosure, such as Figure 2 As shown, the hydraulic turbine assembly 10 includes a supporting base 11, a turbine housing 12, a diverter plate 13, a rotating shaft 14 and a rotating blade 141. The supporting base 11, the turbine housing 12 and the diverter plate 13 are coaxially arranged in the housing 20 from top to bottom. The rotating blade 141 is fixed on the rotating shaft 14, and the rotating blade 141 and the rotating shaft 14 are located in the turbine housing 12. One end of the rotating shaft 14 is rotatably inserted on the supporting base 11, and the other end of the rotating shaft 14 passes through the diverter plate 13 and is fixedly connected to the rotating sleeve 30 (see Figure 3 The supporting base 11 and the diverter plate 13 both have a first liquid channel extending along the axial direction of the housing 20 , and the first liquid channel is communicated with the inner hole of the housing 20 .

[0041] Exemplarily, the supporting base 11 has a first positioning hole 11a and at least one first connecting hole 11b arranged around the first positioning hole 11a. The diverter plate 13 has a second positioning hole 13a and at least one second connecting hole 13b arranged around the second positioning hole 13a. The axis of the first positioning hole 11a and the second positioning hole 13a coincides with the axis of the housing 20. One end of the rotating shaft 14 is inserted into the first positioning hole 11a, and the other end of the rotating shaft 14 passes through the second positioning hole 13a. By providing the first positioning hole 11a and the second positioning hole 13a, the axial positioning of the rotating shaft 14 can be helped.

[0042] Among them, at least one first communicating hole 11 b and at least one second communicating hole 13 b are connected to the inner hole of the turbine housing 12 to form a first liquid channel.

[0043] The best way to improve cement displacement efficiency is to use movable casing and turbulent displacement. However, in actual construction, movable casing is difficult to implement due to various difficulties. This is especially true for horizontal wells, especially when the horizontal section of the pipe string forms wide and narrow sides under deadweight operation. The drilling fluid at the narrow side cannot participate in circulating mud, cementing and displacement, so it is difficult to improve the cementing quality of the horizontal section.

[0044] When the casing shoe provided by the embodiment of the present disclosure is used, the fluid is injected into the inner hole of the housing 20 and then enters the first liquid channel, that is, it flows into the turbine housing 12 through at least one first communication hole 11b on the supporting base 11 and flows out from at least one second communication hole 13b on the diverter plate 13.

[0045] At this time, the rotating blades 141 and the rotating shaft 14 in the turbine housing 12 can perform a certain period of rotational motion driven by the fluid. With the movement of the rotating blades 141, the diverter plate 11 will generate periodic pressure waves, forming axial vibration waves. The waves can act on the medium, destroy the structure between particles and molecules of the medium, change its original physical and chemical properties, and interfere with some reaction processes. In this way, the drilling fluid at the narrow edge will be more completely displaced, thereby significantly improving the cementing displacement efficiency of the horizontal section, avoiding the generation of micro gaps, and improving the cementing quality.

[0046] Optionally, a plurality of annular sealing rings 12a are provided between the outer peripheral wall of the turbine housing 12 and the inner peripheral wall of the housing 20. The plurality of annular sealing rings 12a are respectively located at both ends of the turbine housing 12.

[0047] Optionally, at least one rotating blade 141 is fixed on the rotating shaft 14. The rotating blade 141 includes a first blade 141a and a second blade 141b. The outer diameter of the first blade 141a matches the inner diameter of the housing 20. The outer diameter of the second blade 141b is smaller than the inner diameter of the housing 20, and a counterweight plate 15 is fixed at one end of the second blade 141b away from the rotating shaft 14.

[0048] By fixing the counterweight plate 15 on the second blade 141b with a smaller size, the counterweight plate 15 can rotate periodically with the rotating blade 141 to form a radial vibration. Therefore, the casing shoe provided by the embodiment of the present disclosure can generate bidirectional vibration waves in the axial and radial directions, which is beneficial to further improving the annular displacement efficiency.

[0049] Optionally, the counterweight plate 15 is an arc-shaped plate, and the central angle corresponding to the arc-shaped plate is 60° to 180°.

[0050] If the central angle corresponding to the arc-shaped plate is too large, the weight of the arc-shaped plate is too large, and the eccentric vibration effect will be weakened under the counteraction of the equivalent centrifugal force, and the role of generating radial vibration waves cannot be achieved. If the central angle corresponding to the arc-shaped plate is too small, the weight of the arc-shaped plate is too small, and the role of generating radial vibration waves cannot be achieved.

[0051] Figure 3 is a partial structural half-sectional view of a casing shoe provided by an embodiment of the present disclosure. As Figure 3 shown, the eccentric rotating head 40 has a central through hole 40a, and the rotating sleeve 30 has a communication hole 30a for communicating the central through hole 40a and the first liquid channel.

[0052] When the fluid flows out from the first liquid channel, it can flow into the inner hole of the housing 20 through the communication hole 30a on the rotating sleeve 30, and then flow out from the central through hole 40a.

[0053] Optionally, at least one side hole 40b for communicating the central through hole 40a and the outside is further provided on the side wall of the eccentric rotating head 40. When the fluid displacement is large, the provision of the side hole 40b is beneficial to the rapid discharge of the fluid at the eccentric rotating head 40.

[0054] In the embodiment of the present disclosure, the center of gravity of the eccentric rotating head 40 is located outside the axis of the eccentric rotating head 40.

[0055] Optionally, the eccentric rotating head 40 includes a second connecting shaft 41 and a rotating head 42 connected coaxially. The end face diameter of the rotating head 42 at the end connected to the second connecting shaft 41 is larger than the outer diameter of the second connecting shaft 41.

[0056] Among them, the rotating head 42 is an eccentric drill bit with a pointed top.

[0057] Optionally, the eccentric rotating head 40 can be made of aviation aluminum material, which can effectively ensure the strength and toughness of the eccentric rotating head 40. At the same time, it can also reduce the rotational resistance between the eccentric rotating head 40 and the rotating sleeve 30 during rotation, ensuring that the eccentric rotating head 40 can smoothly penetrate obstacles.

[0058] Optionally, referring to Figure 3 , the casing shoe 100 further includes a first fixing ring 51, a first positioning sleeve 52 and a first bearing 53.

[0059] The rotating sleeve 30 includes a first connecting shaft 31 and a sleeve 32 connected coaxially. The outer diameter of the sleeve 32 is larger than the outer diameter of the first connecting shaft 31, and the outer diameter of the sleeve 32 matches the inner diameter of the housing 20.

[0060] The first fixing ring 51, the first positioning sleeve 52 and the first bearing 53 are sleeved on the outside of the first connecting shaft 31 in sequence from top to bottom. The first fixing ring 51 is fixedly connected to the first connecting shaft 31. The first positioning sleeve 52 is movably sleeved on the outside of the first connecting shaft 31 and fixed to the lower end of the housing 20. The first bearing 53 is clamped between the end faces of the first positioning sleeve 52 and the sleeve 32.

[0061] By providing the first fixing ring 51, the rotating sleeve 30 can be prevented from disengaging from the first positioning sleeve 52. By providing the first positioning sleeve 52, axial positioning of the rotating sleeve 30 can be achieved. By providing the first bearing 53, the rotating sleeve 30 can rotate relative to the housing 20, realizing the rotational connection between the rotating sleeve 30 and the housing 20.

[0062] Optionally, a plurality of annular sealing rings are provided between the inner peripheral wall of the first positioning sleeve 52 and the outer peripheral wall of the first connecting shaft 31 of the rotating sleeve 30, and between the outer peripheral wall of the first positioning sleeve 52 and the inner peripheral wall of the housing 20.

[0063] Optionally, the casing shoe 100 further includes a second fixing ring 61, a second positioning sleeve 62 and a second bearing 63.

[0064] The second fixing ring 61, the second positioning sleeve 62 and the second bearing 63 are sleeved on the outside of the second connecting shaft 41 in sequence from top to bottom. The second fixing ring 61 is fixedly connected to the second connecting shaft 41. The second positioning sleeve 62 is movably sleeved on the outside of the second connecting shaft 41 and fixed to the lower end of the rotating sleeve 30. The second bearing 63 is clamped between the end faces of the second positioning sleeve 62 and the rotating head 42.

[0065] By providing the second fixing ring 61, the eccentric rotating head 40 can be prevented from disengaging from the second positioning sleeve 62. By providing the second positioning sleeve 62, axial positioning of the eccentric rotating head 40 can be achieved. By providing the second bearing 63, the eccentric rotating head 40 can rotate relative to the rotating sleeve 30, realizing the rotational connection between the rotating sleeve 30 and the eccentric rotating head 40.

[0066] Optionally, a plurality of annular sealing rings are provided between the second positioning sleeve 62 and the second connecting shaft 41 of the eccentric rotating head 40, and also between the second positioning sleeve 62 and the second connecting shaft 41.

[0067] Figure 4 is a half-sectional view of a float collar assembly provided by an embodiment of the present disclosure. As Figure 4 shown, the casing shoe 100 further includes a float collar assembly 70 located within the housing 20. The float collar assembly 70 is located above the hydraulic turbine assembly 10. The float collar assembly 70 includes a valve seat 71, a valve rod 72, a spring member 74, and a flow splitting base 73 that are coaxially located within the housing 20 from top to bottom in sequence.

[0068] The valve seat 71 is fixedly connected to the housing 20. One end of the valve seat 71 is fixedly connected to the flow splitting base 73. The valve seat 71 and the flow splitting base 73 form a second liquid passage extending along the axial direction of the housing 20, and the second liquid passage communicates with the inner hole of the housing 20.

[0069] The valve rod 72 is located between the second liquid passages. One end of the valve rod 72 has a blocking portion 721. The spring member 74 is sleeved outside the valve rod 72, and the spring member 74 is clamped between the blocking portion 721 and the flow splitting base 73. The valve rod 72 is configured to block the second liquid passage under the elastic force of the spring member 74 to disconnect the communication between the second liquid passage and the inner hole of the housing 20.

[0070] Optionally, the valve seat 71 is a seat body having a third communication hole 71a extending along the axial direction of the housing 20 in the middle. The flow splitting base 73 is a cylindrical structure with one end open and the other end closed. The open end of the flow splitting base 73 is fixedly connected to the valve seat 71 by bolts. The closed end of the flow splitting base 73 has at least one fourth communication hole 73a extending along the axial direction of the housing 20. The third communication hole 71a and the fourth communication hole 73a communicate to form the second liquid passage.

[0071] Among them, a positioning through hole is further provided in the middle of the closed end of the flow splitting base 73. The central axis of the positioning through hole coincides with the central axis of the housing 20. One end of the valve rod 72 is inserted into the positioning through hole.

[0072] Optionally, the closed end of the flow splitting base 73 has a plurality of fourth communication holes 73a, and the plurality of fourth communication holes 73a are arranged at intervals along the circumferential direction of the flow splitting base 73.

[0073] In the normal state, under the elastic force of the spring member 74, the blocking portion 721 of the valve rod 72 abuts against the valve seat 71 to block the third communication hole 71a, so that the third communication hole 71a cannot communicate with the fourth communication hole 73a, and the second liquid passage is blocked.

[0074] When fluid is injected into the inner hole of the housing 20, the fluid can overcome the elastic force of the spring member 74 and enter the second liquid passage from the third communication hole 71a on the valve seat 71. At this time, under the action of the fluid, the valve rod 72 moves downward, the spring member 74 is compressed, the blocking portion 721 of the valve rod 72 is separated from the valve seat 71, the third communication hole 71a can communicate with the fourth communication hole 73a, and the fluid can flow out from the fourth communication hole 73a.

[0075] In the embodiment of the present disclosure, the second liquid passage can communicate with the first liquid passage.

[0076] When the fluid flows reversely into the inner hole from the fourth communication hole 73a, under the action of the fluid and the spring member 74, the blocking portion of the valve rod 72 will always abut against the valve seat 71 to block the third communication hole 71a, thereby preventing the fluid from flowing back and realizing the functions of reverse interception and forward drainage.

[0077] Exemplarily, the spring member 224 can be a spring.

[0078] Optionally, the casing shoe 100 further includes a well shut-off assembly 80 located inside the housing 20. The well shut-off assembly 80 is located above the float collar assembly 70, and the well shut-off assembly 80 includes a fixed seat 81 and a sliding sleeve 82.

[0079] The fixed seat 81 is fixedly connected to the housing 20, and the fixed seat 81 is a cylindrical structure with one end open and the other end closed. At least one liquid circulation hole 81a is provided on the side wall of the fixed seat 81, and at least one liquid circulation hole 81a is used to communicate the inside of the fixed seat 81 with the inner hole of the housing 20.

[0080] The sliding sleeve 82 is located inside the fixed seat 81, and the sliding sleeve 82 is configured to be operably slid from a first position to a second position. When the sliding sleeve 82 is in the first position, at least one liquid circulation hole 81a communicates the inside of the fixed seat 81 with the inner hole of the housing 20; when the sliding sleeve 82 is in the second position, the sliding sleeve 82 blocks at least one liquid circulation hole 81a to disconnect the communication between the inside of the fixed seat 81 and the inner hole of the housing 20.

[0081] By providing the well shut-off assembly 80, hard well shut-off can be achieved during bump pressure to ensure that the fluid does not flow back.

[0082] During specific use, when the cement plug descends to the upper end face of the sliding sleeve 82, bump pressure is generated, pushing the sliding sleeve 81 downward to close at least one liquid circulation hole 81a on the fixed seat 81, and permanent well shut-off at the bottom of the well can be achieved. At this time, even if the fluid flows back through the float collar assembly 70, the well shut-off assembly 80 can still play a role in secondary prevention of backflow.

[0083] Optionally, the sliding sleeve 82 is a cylinder with a flange plate 821 at one end. The diameter of the flange plate 821 is greater than the inner diameter of the fixed seat 81, and the other end of the sliding sleeve 82 is located inside the fixed seat 81. By providing the flange plate 821, it is possible to prevent the sliding sleeve 82 from completely sliding into the fixed seat 81, which is not convenient for removal.

[0084] The shut-in assembly 80 adopts the sliding sleeve principle, and the components that play a sealing role do not participate in the fluid circulation, which can largely avoid the erosion damage of the circulating fluid to the sealing components.

[0085] Optionally, there is at least one first annular sealing ring 831 between the inner peripheral wall of the fixed seat 81 and the outer peripheral wall of the sliding sleeve 82, and at least one second annular sealing ring 832 between the outer peripheral wall of the fixed seat 81 and the inner peripheral wall of the housing 20.

[0086] Optionally, the fixed seat 81 and the sliding sleeve 82 are fixedly connected by a pin 83.

[0087] In the embodiment of the present disclosure, the pin 83 will be sheared when it is subjected to an impact force greater than 3 MPa, so that the sliding sleeve 82 slides into the fixed seat 81 and seals at least one liquid flow hole 81a.

[0088] Optionally, the casing shoe 100 includes a support sleeve 90 for supporting the shut-in assembly 80. The support sleeve 90 is located between the float collar assembly 70 and the shut-in assembly 80. The support sleeve 90 can play a role of limiting and supporting, effectively limiting the distance between the two assemblies during installation, and preventing the shut-in assembly 80 from moving downward during the bump pressure process and contacting the float collar assembly 70, causing damage to the float collar assembly 70.

[0089] Optionally, the open end of the fixed seat 81 has an annular plate 811 extending radially outward along the fixed seat 81.

[0090] Exemplarily, the support sleeve 90 is coaxially arranged in the housing 20, and the support sleeve 90 is located between the annular plate 811 and the valve seat 71 of the float collar assembly 70, and the support sleeve 90 is sleeved outside the fixed seat 81 of the cylindrical structure.

[0091] The following briefly describes the operation process of a casing shoe provided by the embodiment of the present disclosure during on-site application:

[0092] 1. Install the casing shoe provided by the embodiment of the present disclosure before the casing.

[0093] 2. Run the casing according to the requirements of the cementing operation.

[0094] 3. When grouting the casing string into the open-hole deviated section, keep moving the casing continuously during the grouting interval, and the vertical movement distance of the casing should be no less than 2 cm. When signs of downhole resistance are detected, stop grouting and take measures such as moving the casing over a large distance or connecting the kelly bar to circulate. After it returns to normal, continue grouting and running the casing.

[0095] 4. After the casing string enters the open-hole deviated section, control the running speed of the casing string, and it is recommended not to exceed 2 joints / min.

[0096] 5. After the casing string enters the open-hole deviated section, pay attention to the return slurry at the wellhead in a timely manner. If any abnormality occurs, immediately stop running the casing for treatment. After it returns to normal, continue running the casing.

[0097] 6. After the casing encounters resistance, if the pipe string still cannot be released by moving it up and down, first connect the kelly bar or circulation head to start the pump for circulation, use the hydraulic power to start the reaming guide head to rotate and break through the resistance, and then, under the condition of the safety of the casing and equipment, move the casing up and down as many times as possible.

[0098] 7. When the casing reaches the designed position, install the cement head according to the cementing design. After circulating with a small displacement to make it unobstructed, circulate and wash the well with the normal displacement.

[0099] 8. Subsequent operations such as cementing displacement and plugging the rubber plug are carried out normally according to the operation procedures.

[0100] 9. After the cementing plug reaches the bottom, apply the bump pressure, record the pressure of the wellhead pressure gauge, and continue to apply pressure with a small displacement of 3 - 5 MPa to ensure that the anti-backflow check valve closes normally. No backwater at the wellhead indicates successful well shut-in.

[0101] The above are only optional embodiments of the present disclosure, and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present disclosure shall be included within the protection scope of the present disclosure.

Claims

1. A casing shoe, characterized in that, The casing shoe (100) includes a hydraulic turbine assembly (10), a float collar assembly (70), and a housing (20), a rotating sleeve (30), and an eccentric rotating head (40) that are coaxially connected in sequence from top to bottom. The housing (20) is rotatably connected to the rotating sleeve (30), and the rotating sleeve (30) is rotatably connected to the eccentric rotating head (40). The hydraulic turbine assembly (10) and the float collar assembly (70) are located within the housing (20), and the float collar assembly (70) is located above the hydraulic turbine assembly (10). The hydraulic turbine assembly (10) is configured to drive the rotating sleeve (30) to rotate relative to the housing (20) under the action of hydraulic force. The hydraulic turbine assembly (10) includes a supporting base (11), a turbine housing (12), a diverter plate (13), a rotating shaft (14), and rotating blades (141). The supporting base (11), the turbine housing (12), and the diverter plate (13) are coaxially arranged in the housing (20) from top to bottom in sequence. The rotating blades (141) are fixed to the rotating shaft (14), and the rotating blades (141) and the rotating shaft (14) are located within the turbine housing (12). One end of the rotating shaft (14) is rotatably inserted into the supporting base (11), and the other end of the rotating shaft (14) passes through the diverter plate (13) and is fixedly connected to the rotating sleeve (30). The supporting base (11) and the diverter plate (13) each have a first liquid passage extending along the axial direction of the housing (20), and the first liquid passage communicates with the inner bore of the housing (20). A plurality of drill blocks are circumferentially spaced apart on the outer wall of the rotating sleeve (30). The plurality of drill blocks are arranged in a spiral pattern. The plurality of drill blocks are all made of tungsten carbide hard alloy material. The eccentric rotating head (40) has a central through-hole (40a). The rotating sleeve (30) has a communication hole (30a) for communicating the central through-hole (40a) and the first liquid passage. The side wall of the eccentric rotating head (40) further has at least one side hole (40b) for communicating the central through-hole (40a) and the outside.

2. The casing shoe according to claim 1, wherein, At least one of the rotating blades (141) is fixed to the rotating shaft (14). The rotating blade (141) includes a first blade (141a) and a second blade (141b). The outer diameter of the first blade (141a) matches the inner diameter of the housing (20). The outer diameter of the second blade (141b) is smaller than the inner diameter of the housing (20), and a counterweight plate (15) is fixed to the end of the second blade (141b) away from the rotating shaft (14).

3. The casing shoe according to claim 2, wherein, The counterweight plate (15) is an arc-shaped plate, and the central angle corresponding to the arc-shaped plate is 60° to 180°.

4. The casing shoe according to claim 1, characterized in that, The casing shoe (100) further includes a first fixing ring (51), a first positioning sleeve (52), and a first bearing (53). The rotating sleeve (30) includes a first connecting shaft and a sleeve (32) that are coaxially connected, and the outer diameter of the sleeve (32) is greater than the outer diameter of the first connecting shaft; The first fixing ring (51), the first positioning sleeve (52), and the first bearing (53) are sleeved on the outside of the first connecting shaft in sequence from top to bottom. The first fixing ring (51) is fixedly connected to the first connecting shaft. The first positioning sleeve (52) is movably sleeved on the outside of the first connecting shaft and is fixed to the lower end of the housing (20). The first bearing (53) is clamped between the end faces of the first positioning sleeve (52) and the sleeve (32).

5. The casing shoe according to claim 1, characterized in that, The casing shoe (100) further includes a second fixing ring (61), a second positioning sleeve (62), and a second bearing (63); The eccentric rotating head (40) includes a second connecting shaft (41) and a rotating head (42) that are coaxially connected, and the end face diameter of the end of the rotating head (42) connected to the second connecting shaft (41) is greater than the outer diameter of the second connecting shaft (41); The second fixing ring (61), the second positioning sleeve (62), and the second bearing (63) are sleeved on the outside of the second connecting shaft (41) in sequence from top to bottom. The second fixing ring (61) is fixedly connected to the second connecting shaft (41). The second positioning sleeve (62) is movably sleeved on the outside of the second connecting shaft (41) and is fixed to the lower end of the rotating sleeve (30). The second bearing (63) is clamped between the end faces of the second positioning sleeve (62) and the rotating head (42).

6. The casing shoe according to claim 1, wherein, The float collar assembly (70) includes a valve seat (71), a valve rod (72), a spring member (74), and a diverter base (73) that are coaxially located inside the housing (20) in sequence from top to bottom; The valve seat (71) is fixedly connected to the housing (20). One end of the valve seat (71) is fixedly connected to the diverter base (73). The valve seat (71) and the diverter base (73) form a second liquid passage extending along the axial direction of the housing (20), and the second liquid passage communicates with the inner hole of the housing (20); The valve rod (72) is located in the second liquid passage. One end of the valve rod (72) has a blocking portion (721). The spring member (74) is sleeved on the valve rod (72), and the spring member (74) is clamped between the blocking portion (721) and the diverter base (73). The valve rod (72) is configured to block the second liquid passage and disconnect the communication between the second liquid passage and the inner hole of the housing (20) under the elastic force of the spring member (74).

7. The casing shoe according to any one of claims 1 to 6, characterized in that, The casing shoe (100) further includes a well shut-off assembly (80) located inside the housing (20). The well shut-off assembly (80) is located above the float collar assembly (70). The well shut-off assembly (80) includes a fixed seat (81) and a sliding sleeve (82). The fixed seat (81) is fixedly connected to the housing (20). The fixed seat (81) is a cylindrical structure with one end open and the other end closed. At least one liquid flow hole (81a) is provided on the side wall of the fixed seat (81), and the at least one liquid flow hole (81a) is used to communicate the inside of the fixed seat (81) with the inner hole of the housing (20). The sliding sleeve (82) is located inside the fixed seat (81). The sliding sleeve (82) is configured to slidably move from a first position to a second position operably. When the sliding sleeve (82) is in the first position, the at least one liquid flow hole (81a) communicates the inside of the fixed seat (81) with the inner hole of the housing (20). When the sliding sleeve (82) is in the second position, the sliding sleeve (82) blocks the at least one liquid flow hole (81a) to disconnect the communication between the inside of the fixed seat (81) and the inner hole of the housing (20).

8. The casing shoe according to claim 7, characterized in that, The sliding sleeve (82) is a cylinder with a flange plate (821) at one end. The diameter of the flange plate (821) is greater than the inner diameter of the fixed seat (81), and the other end of the sliding sleeve (82) is located inside the fixed seat (81).

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