Mechanical drilling liner suspension sealing device and well drilling system

Abstract

The mechanical tail pipe hanging sealing device comprises a releasing sub, a base pipe, a hanging sleeve and a sitting hanging sleeve, the upper end of the sitting hanging sleeve is connected with the lower portion of an upper-layer casing pipe, the lower end of the releasing sub is connected with the upper end of the base pipe through an extrusion sleeve, and the lower end of the base pipe is inserted into an opening in the upper end of the hanging sleeve; the hanging sleeve is inserted into the sitting hanging sleeve, the sitting hanging sleeve supports the hanging sleeve upwards, the outer wall of the base pipe is sleeved with a sealing rubber sleeve, the upper end of the sealing rubber sleeve abuts against the lower end of the extrusion sleeve, the lower end of the sealing rubber sleeve abuts against the upper end of the hanging sleeve, and the base pipe can move downwards relative to the hanging sleeve. The extrusion sleeve is driven to move downwards to extrude the sealing rubber barrel, and the sealing rubber barrel bulges outwards to be in sealing contact with the inner wall of the upper-layer casing pipe. The drilling liner can be hung and sealed in a mechanical mode, operation is easy, sealing is reliable, the risk is low, cost is low, the drilling liner is suitable for well completion operation in various environments, hydraulic sitting hanging and slip hanging are not needed, and the field application advantage is obvious.

Description

Technical Field

[0001] The present invention relates to the field of drilling equipment, and in particular to a mechanical liner suspension sealing device. In addition, the present invention also relates to a drilling system comprising the mechanical liner suspension sealing device. Background Art

[0002] With the continuous deepening of oilfield development, liner completion technology has developed rapidly, and its completion methods have shown a trend of multi-form and diversified development, becoming one of the indispensable completion methods in side-drilled wells, deep wells, ultra-deep wells, complex structure wells and special process wells. The casing string that has not extended to the wellhead is called the liner. The liner is usually sent down with a drill pipe, and the liner is suspended in the upper casing by a liner hanger to perform liner cementing or screen completion operations. It is widely used in liner operations in complex wells such as side-drilled wells, deepening wells, ultra-deep wells and small clearance wells.

[0003] At present, the liner hanger is mainly divided into the slip-type liner hanger and the expansion type liner hanger. Various slip-type liner hangers mainly use the hydraulic cylinder to push the slip teeth to achieve the suspension of the liner column. Some slip-type hangers have special functions such as top sealing and rotating liner to meet the requirements of special well conditions. However, the structure is relatively complex, there is a risk of complex situations underground, the price cost is relatively high, and there are still certain application limitations in the low-cost market and the market with strict cost control.

[0004] The present invention aims to provide a mechanical tail pipe suspension and sealing device, which realizes the inclined surface suspension and top sealing operation of the tail pipe by means of the tail pipe column gravity. Summary of the invention

[0005] The object of the present invention is to provide a mechanical liner suspension and sealing device, which can achieve the suspension and sealing of the liner by mechanical means, has simple operation, reliable sealing, low risk, low cost, and is suitable for completion operations in various environments. Another object of the present invention is to provide a drilling system including the above-mentioned mechanical liner suspension and sealing device.

[0006] In order to solve the above technical problems, the present invention provides a mechanical tail pipe suspension sealing device, comprising a coaxially arranged release joint, a base pipe, a suspension sleeve and a seating sleeve, the upper end of the seating sleeve is connected to the lower part of an upper casing, the lower end of the release joint is connected to the upper end of the base pipe through an extrusion sleeve, the lower end of the base pipe is inserted into the upper end opening of the suspension sleeve, the base pipe and the release joint extend into the interior of the upper casing, the suspension sleeve is inserted into the interior of the seating sleeve, the seating sleeve supports the suspension sleeve upward, a sealing rubber sleeve is sleeved on the outer wall of the base pipe, the upper end of the sealing rubber sleeve abuts against the lower end of the extrusion sleeve, the lower end of the sealing rubber sleeve abuts against the upper end of the suspension sleeve, the base pipe can move downward relative to the suspension sleeve, and drive the extrusion sleeve to move downward to extrude the sealing rubber sleeve, the sealing rubber sleeve bulges outward and is in sealing contact with the inner wall of the upper casing.

[0007] Preferably, it also includes a casing nipple, the upper end of which extends into the lower end opening of the base pipe and is fixedly connected, the lower end of which is connected to the tail pipe, and the casing nipple passes through the hanging sleeve and the sitting sleeve.

[0008] Preferably, a stepped hole is provided in the suspension sleeve, a limiting step is provided in the middle of the stepped hole, the upper end diameter of the stepped hole matches the outer wall diameter of the base pipe, the lower end diameter of the stepped hole matches the diameter of the casing short section, and the limiting step can be offset against the lower end of the base pipe to limit the descending stroke of the base pipe.

[0009] Preferably, a shear pin is connected between the lower end of the outer wall of the base pipe and the upper end of the inner wall of the suspension sleeve, so that a descending travel distance is provided between the lower end of the base pipe and the limiting step before the sealing operation.

[0010] Preferably, the outer wall of the suspension sleeve is provided with a downwardly contracted suspension slope, and the inner wall of the sitting sleeve is provided with a sitting bearing surface in contact with the suspension slope, the sitting bearing surface and the suspension slope have the same inclination angle, and the sitting bearing surface supports the suspension slope.

[0011] Preferably, the upper end of the seating sleeve is provided with an internal thread connected to the upper casing, and the lower end of the seating sleeve is provided with an external thread connected to a float shoe.

[0012] Preferably, the upper end of the release joint is provided with an internal thread connected to the drill pipe, and the lower end of the release joint is provided with an external thread connected to the extrusion sleeve.

[0013] Preferably, the drop-out connector is connected to the extrusion sleeve via a reverse thread.

[0014] Preferably, it comprises a plurality of the sealing rubber tubes arranged in sequence along the axial direction, and a spacer ring is provided between adjacent sealing rubber tubes.

[0015] The present invention also provides a drilling system, comprising the mechanical tail pipe suspension sealing device as described in any one of the above items.

[0016] The present invention provides a mechanical tail pipe suspension sealing device, comprising a coaxially arranged release joint, a base pipe, a suspension sleeve and a seating sleeve, wherein the upper end of the seating sleeve is connected to the lower part of an upper casing, the lower end of the release joint is connected to the upper end of the base pipe through an extrusion sleeve, the lower end of the base pipe is inserted into the upper end opening of the suspension sleeve, the base pipe and the release joint extend into the interior of the upper casing, the suspension sleeve is inserted into the interior of the seating sleeve, the seating sleeve supports the suspension sleeve upward, a sealing rubber sleeve is sleeved on the outer wall of the base pipe, the upper end of the sealing rubber sleeve abuts against the lower end of the extrusion sleeve, the lower end of the sealing rubber sleeve abuts against the upper end of the suspension sleeve, the base pipe can move downward relative to the suspension sleeve, and drive the extrusion sleeve to move downward to extrude the sealing rubber sleeve, the sealing rubber sleeve bulges outwards and is in sealing contact with the inner wall of the upper casing.

[0017] During the suspension operation, the seating sleeve is first put into the well with the upper casing, and after the other devices and the liner are put into the well, the liner and base pipe move downward along the active stroke under the action of gravity, driving the extrusion sleeve downward to squeeze the sealant tube, realizing the deformation and sealing of the sealant tube, and completing the suspension and sealing operation of the liner. The suspension and sealing of the liner can be achieved mechanically, with simple operation, reliable sealing, low risk, low cost, and suitable for completion operations in various environments. It does not require hydraulic seating and slip suspension, and has obvious advantages in field application.

[0018] The present invention also provides a drilling system including the mechanical liner suspension sealing device. Since the mechanical liner suspension sealing device has the technical effects, the drilling system should also have the same technical effects, which will not be described in detail herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic structural diagram of a specific implementation of the mechanical tail pipe suspension sealing device provided by the present invention;

[0020] Figure 2 A structural schematic diagram of a hanging sleeve in a specific implementation manner of the mechanical tail pipe hanging sealing device provided by the present invention;

[0021] Figure 3 A schematic diagram of a well-entering operation of a hanging sleeve of a specific embodiment of the mechanical liner hanging sealing device provided by the present invention;

[0022] Figure 4 A schematic diagram of the suspension operation of a specific embodiment of the mechanical tail pipe suspension sealing device provided by the present invention;

[0023] Figure 5 A schematic diagram of sealing operation of a specific implementation of the mechanical tail pipe suspension sealing device provided by the present invention;

[0024] Figure 6 A schematic diagram of a hands-off operation of a specific implementation of the mechanical tail pipe suspension sealing device provided by the present invention.

[0025] Among them, there are the release joint 1, base pipe 2, hanging sleeve 3, limit step 31, shear pin 32, hanging slope 33, sitting sleeve 4, sitting bearing surface 41, upper casing 5, extrusion sleeve 6, sealing rubber tube 7, casing short section 8, tail pipe 9, floating shoe 10, drill pipe 11, and spacer ring 12. DETAILED DESCRIPTION

[0026] The core of the present invention is to provide a mechanical liner suspension and sealing device, which can achieve the suspension and sealing of the liner by mechanical means, has simple operation, reliable sealing, low risk, low cost, and is suitable for completion operations in various environments. Another core of the present invention is to provide a drilling system including the above-mentioned mechanical liner suspension and sealing device.

[0027] In order to enable those skilled in the art to better understand the solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0028] Please refer to Figures 1 to 6 , Figure 1 A schematic structural diagram of a specific implementation of the mechanical tail pipe suspension sealing device provided by the present invention; Figure 2 A structural schematic diagram of a hanging sleeve in a specific implementation manner of the mechanical tail pipe hanging sealing device provided by the present invention;

[0029] Figure 3 A schematic diagram of a well-entering operation of a hanging sleeve of a specific embodiment of the mechanical liner hanging sealing device provided by the present invention; Figure 4 A schematic diagram of the suspension operation of a specific embodiment of the mechanical tail pipe suspension sealing device provided by the present invention; Figure 5 A schematic diagram of sealing operation of a specific implementation of the mechanical tail pipe suspension sealing device provided by the present invention; Figure 6 A schematic diagram of a hands-off operation of a specific implementation of the mechanical tail pipe suspension sealing device provided by the present invention.

[0030] The specific embodiment of the present invention provides a mechanical tail pipe suspension sealing device, including a coaxially arranged release joint 1, a base pipe 2, a suspension sleeve 3 and a seat sleeve 4, and each component is a pipe fitting that penetrates axially from top to bottom. Among them, the seat sleeve 4 is put into the well separately from other components, the seat sleeve 4 is fixed in position, the upper end of the seat sleeve 4 is connected to the lower part of the upper casing 5, and the lower end of the seat sleeve 4 is connected to the floating shoe 10. On the other hand, the upper end of the release joint 1 is connected to the drill pipe 11, and an extrusion sleeve 6 is also provided. The upper end of the extrusion sleeve 6 is connected to the lower end of the release joint 1, and the lower end of the extrusion sleeve 6 is connected to the upper end of the base pipe 2. The lower end of the base pipe 2 is inserted into the upper end opening of the suspension sleeve 3. Furthermore, when other components are put into the well, the drill pipe 11 drives the release joint 1, the base pipe 2 and the suspension sleeve 3 to extend into the interior of the upper casing 5, and the suspension sleeve 3 is inserted into the interior of the seat sleeve 4, and the seat sleeve 4 supports the suspension sleeve 3 upward. The outer wall of the base pipe 2 is sleeved with a sealing rubber tube 7, the upper end of the sealing rubber tube 7 is abutted against the lower end of the extrusion sleeve 6, and the lower end of the sealing rubber tube 7 is abutted against the upper end of the hanging sleeve 3. During the sealing operation, under the action of gravity, the tail pipe 9 pulls the base pipe 2 and the extrusion sleeve 6 to move downward, that is, the base pipe 2 moves downward relative to the hanging sleeve 3, driving the extrusion sleeve 6 to move downward to squeeze the sealing rubber tube 7, and the sealing rubber tube 7 bulges outward to make sealing contact with the inner wall of the upper casing 5.

[0031] During the suspension operation, the seating sleeve 4 is first put into the well along with the upper casing 5. After the other devices and the liner 9 are put into the well, the liner 9 and the base pipe 2 move downward along the active stroke under the action of gravity, driving the extrusion sleeve 6 to move downward to extrude the sealing rubber tube 7, so as to achieve the deformation and sealing of the sealing rubber tube 7, and complete the suspension and sealing operation of the liner 9. The suspension and sealing of the liner 9 can be achieved mechanically, which is simple to operate, reliable to seal, low in risk, low in cost, and suitable for completion operations in various environments. It does not require hydraulic seating and slip suspension, and has obvious advantages in field application.

[0032] Furthermore, a casing pup section 8 is provided, the upper end of which extends into the lower end opening of the base pipe 2 and is fixedly connected to the base pipe 2, the lower end of which is connected to the tail pipe 9 through a threaded sleeve, and the casing pup section 8 passes through the hanging sleeve 3 and the sitting sleeve 4.

[0033] Specifically, a stepped hole is provided in the suspension sleeve 3, and a limiting step 31 is provided in the middle of the stepped hole. The diameter of the upper end of the stepped hole matches the diameter of the outer wall of the base pipe 2, and the diameter of the lower end of the stepped hole matches the diameter of the casing short section 8. Therefore, the diameter of the upper end of the stepped hole is larger than the diameter of the lower end of the stepped hole, so that the end face of the limiting step 31 faces upward. Before the sealing operation, there is a descending stroke distance between the lower end of the base pipe 2 and the limiting step 31. During the sealing operation, as the base pipe 2 moves downward relative to the suspension sleeve 3, the base pipe 2 continues to extend into the suspension sleeve 3 along the descending stroke distance until the lower end of the base pipe 2 abuts against the limiting step 31, indicating that the base pipe 2 has descended into place, which is used to limit the descending stroke of the base pipe 2.

[0034] In order to fix the relative position of the base pipe 2 and the suspension sleeve 3 before the sealing operation, a shear pin 32 is connected between the lower end of the outer wall of the base pipe 2 and the upper end of the inner wall of the suspension sleeve 3 to ensure the descending travel distance. When the sealing operation starts, the shear pin 32 is sheared to enable the base pipe 2 to move downward.

[0035] In the mechanical tail pipe suspension sealing device provided by the specific embodiment of the present invention, in order to make the seating sleeve 4 stably support the suspension sleeve 3, a downwardly contracted suspension slope 33 is provided on the outer wall of the suspension sleeve 3, and a seating bearing surface 41 in contact with the suspension slope 33 is provided on the inner wall of the seating sleeve 4. The seating bearing surface 41 and the suspension slope 33 have the same inclination angle, and the seating bearing surface 41 supports the suspension slope 33. When the suspension sleeve 3 enters the seating sleeve 4, the suspension slope 33 is in close contact with and abuts against the seating bearing surface 41, fixing the axial position of the suspension sleeve 3.

[0036] The upper end of the seating sleeve 4 is provided with an internal thread connected to the upper casing 5, and the lower end of the seating sleeve 4 is provided with an external thread connected to the floating shoe 10. The upper end of the release joint 1 is provided with an internal thread connected to the drill pipe 11, and the lower end of the release joint 1 is provided with an external thread connected to the extrusion sleeve 6. Preferably, the release joint 1 is connected to the extrusion sleeve 6 through a reverse thread, and the drill pipe 11 is fed forwardly to disengage the reverse thread connecting the extrusion sleeve 6 and the release joint 1, so as to realize the release operation of the release joint 1 and the tail pipe 9.

[0037] On the basis of the mechanical tail pipe suspension sealing device provided in the above-mentioned specific embodiments, it includes a plurality of sealing rubber tubes 7 arranged in sequence along the axial direction. At the same time, spacer rings 12 are arranged between adjacent sealing rubber tubes 7. The number is adjusted according to the downhole sealing requirements. Specifically, three sealing rubber tubes 7 and two spacer rings 12 can be set. The material of the sealing rubber tube 7 can select rubber parts with different temperature resistance according to the working stability.

[0038] The specific working process is:

[0039] First, the seating sleeve 4 is put into the well for operation. The seating sleeve 4 is connected to the lower part of the upper casing 5 and is first lowered into a designated position in the well, and drilling continues after cementing.

[0040] Secondly, the liner 9 is lowered into the well by running the drill pipe 11 into the liner 9 of the next size, and the hanging sleeve 3 is located at the top of the liner 9 and lowered into the well together.

[0041] Once again, during the hanging operation, when the tail pipe 9 is in place, the hanging inclined surface 33 of the hanging sleeve 3 contacts the seating bearing surface 41 of the seating sleeve 4, and the tail pipe 9 can be seated in the seating sleeve 4 through the hanging sleeve 3. If cementing operation is required, cementing is performed first and then hanging and sealing operation is performed.

[0042] Next, in the sealing operation, after the tail pipe 9 is suspended, under the action of gravity, the tail pipe 9 pulls the casing short section 8 and the base pipe 2 downward along the movable stroke, and the extrusion sleeve 6 extrudes the sealing rubber cylinder 7 as it moves downward to achieve downward extrusion. When the lower end surface of the base pipe 2 contacts the limiting step 31, the movable stroke completely disappears, and the sealing rubber cylinder 7 is deformed and bulged to complete the sealing operation.

[0043] Finally, the release operation is performed. When the tail pipe 9 completes the suspension sealing, it is sent into the drill pipe 11 in the forward direction to disengage the reverse thread connecting the extrusion sleeve 6 and the release joint 1, thereby realizing the release operation of the release joint 1 and the tail pipe 9, pulling out and sending in the drilling tools, and completing the well.

[0044] In addition to the above-mentioned mechanical liner suspension sealing device, a specific embodiment of the present invention further provides a drilling system including the above-mentioned mechanical liner suspension sealing device. The structures of other parts of the drilling system can be referred to the prior art and will not be described in detail herein.

[0045] The mechanical tail pipe suspension sealing device and drilling system provided by the present invention are introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation method of the present invention. The description of the above embodiment is only used to help understand the method and core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A mechanical tail pipe suspension sealing device, It is characterized in that The invention comprises a coaxially arranged release joint (1), a base pipe (2), a suspension sleeve (3) and a sitting sleeve (4); the upper end of the sitting sleeve (4) is connected to the lower part of an upper casing (5); the lower end of the release joint (1) is connected to the upper end of the base pipe (2) via an extrusion sleeve (6); the lower end of the base pipe (2) is inserted into the upper end opening of the suspension sleeve (3); the base pipe (2) and the release joint (1) extend into the interior of the upper casing (5); the suspension sleeve (3) is inserted into the interior of the sitting sleeve (4); the sitting sleeve (4) is The hanging sleeve (4) supports the hanging sleeve (3) upwards, and a sealing rubber tube (7) is sleeved on the outer wall of the base pipe (2). The upper end of the sealing rubber tube (7) abuts against the lower end of the extrusion sleeve (6), and the lower end of the sealing rubber tube (7) abuts against the upper end of the hanging sleeve (3). The base pipe (2) can move downward relative to the hanging sleeve (3) and drive the extrusion sleeve (6) to move downward to squeeze the sealing rubber tube (7). The sealing rubber tube (7) bulges outwards and is in sealing contact with the inner wall of the upper sleeve (5).

2. The mechanical tail pipe suspension sealing device according to claim 1, It is characterized in that It also comprises a casing short section (8), the upper end of which extends into the lower end opening of the base pipe (2) and is fixedly connected, the lower end of which is connected to the tail pipe (9), and the casing short section (8) passes through the suspension sleeve (3) and the seating sleeve (4).

3. The mechanical tail pipe suspension sealing device according to claim 2, It is characterized in that A stepped hole is provided in the suspension sleeve (3), a limiting step (31) is provided in the middle of the stepped hole, the diameter of the upper end of the stepped hole matches the diameter of the outer wall of the base pipe (2), the diameter of the lower end of the stepped hole matches the diameter of the casing short section (8), and the limiting step (31) can abut against the lower end of the base pipe (2) to limit the descending stroke of the base pipe (2).

4. The mechanical tail pipe suspension sealing device according to claim 3, It is characterized in that A shear pin (32) is connected between the lower end of the outer wall of the base pipe (2) and the upper end of the inner wall of the suspension sleeve (3), so that a descending travel distance is provided between the lower end of the base pipe (2) and the limiting step (31) before the sealing operation.

5. The mechanical tail pipe suspension sealing device according to claim 1, It is characterized in that The outer wall of the suspension sleeve (3) is provided with a downwardly contracted suspension slope (33), and the inner wall of the sitting sleeve (4) is provided with a sitting bearing surface (41) in contact with the suspension slope (33); the sitting bearing surface (41) and the suspension slope (33) have the same inclination angle, and the sitting bearing surface (41) supports the suspension slope (33).

6. The mechanical tail pipe suspension sealing device according to claim 5, It is characterized in that The upper end of the seating sleeve (4) is provided with an internal thread connected to the upper casing (5), and the lower end of the seating sleeve (4) is provided with an external thread connected to a floating shoe (10).

7. The mechanical tail pipe suspension sealing device according to claim 1, It is characterized in that The upper end of the release joint (1) is provided with an internal thread connected to the drill rod (11), and the lower end of the release joint (1) is provided with an external thread connected to the extrusion sleeve (6).

8. The mechanical tail pipe suspension sealing device according to claim 7, It is characterized in that The release joint (1) is connected to the extrusion sleeve (6) via a reverse thread.

9. The mechanical tail pipe suspension sealing device according to any one of claims 1 to 8, It is characterized in that It comprises a plurality of sealing rubber tubes (7) arranged in sequence along the axial direction, and a spacer ring (12) is provided between adjacent sealing rubber tubes (7).

10. A drilling system, It is characterized in that It comprises the mechanical tail pipe suspension sealing device as claimed in any one of claims 1 to 9.

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