A continuous drilling equivalent circulation density reduction control device

Abstract

The invention discloses a continuous drilling equivalent circulating density reduction control device, which comprises: an outer tube, which is fixed on a drill string and located at a vertical well section; a mud delivery pipe, which is coaxially arranged in the outer tube, and a mud upward bypass hole is provided on the drill string, and the mud upward bypass hole is connected with the mud delivery pipe and is used for circulating and delivering drilling mud from bottom to top; a water injection callback component, which is arranged in the mud delivery pipe, and the flow direction of the water injection callback component is opposite to the drilling mud delivery direction in the mud delivery pipe; and an upward delivery chamber, which is arranged above the mud delivery pipe.

Description

Technical Field

[0001] The invention belongs to the technical field of drilling mud circulation equipment, in particular to a continuous drilling equivalent circulation density reduction control device. Background Art

[0002] In oil and gas field drilling, the difference between the collapse pressure and the fracture pressure is usually called the pressure window, and is often expressed by equivalent density, often referred to as the density window. When the density window is very narrow and the equivalent circulating density of the drilling mud is close to the fracture pressure curve, the drilling mud is easy to fracture the formation and cause mud loss, resulting in drilling shutdown. Therefore, the equivalent circulating density of the drilling mud must be reduced so that the equivalent circulating density is near the median of the density window to improve the operability of drilling under narrow density window conditions. However, most of the current pressure reduction tools use downhole pumps or rotating blades and other mechanisms to provide power for the upward return fluid to achieve pressure reduction, and cannot fundamentally solve the high equivalent circulating density. Therefore, a person skilled in the art provides a continuous drilling equivalent circulating density reduction control device to solve the problems raised in the above background technology. Summary of the invention

[0003] To achieve the above object, the present invention provides the following technical solution: a continuous drilling equivalent circulation density reduction control device, comprising:

[0004] An outer tube, fixed to the drill string and located at the vertical well section;

[0005] A mud conveying pipe is coaxially arranged in the outer tube, and a mud upward bypass hole is provided on the drill string. The mud upward bypass hole is connected to the mud conveying pipe and is used for circulating and conveying the drilling mud from bottom to top;

[0006] A water injection callback component is arranged in the mud delivery pipe, and the flow direction of the water injection callback component is opposite to the drilling mud delivery direction in the mud delivery pipe; and

[0007] The upper conveying chamber is arranged above the mud conveying pipe.

[0008] Furthermore, as a preference, a plurality of main delivery holes are distributed circumferentially inside the mud delivery pipe, and a circulation bin is symmetrically fixed above and below the mud delivery pipe, the circulation bin is connected with each of the main delivery holes through a joint pipe, a valve seat is fixed below the mud delivery pipe, and the mud upward bypass hole is connected with the circulation bin located below through the valve seat.

[0009] Further, as a preference, the water injection callback component comprises:

[0010] A water accumulation chamber is arranged in the mud conveying pipe, and one side of the water accumulation chamber is vertically connected with a water inlet pipe;

[0011] A delivery pipe, arranged corresponding to each of the main delivery holes;

[0012] A lower flow bin is fixed below the mud delivery pipe, and both ends of the delivery pipe are connected to the water accumulation chamber and the lower flow bin through a transfer pipe;

[0013] An intermediate frame member is fixed at the inner center of the main delivery hole, the delivery pipe is connected to the intermediate frame member, a ball shaft is fixed to the delivery pipe, and the delivery pipe is rotatably connected to the intermediate frame member through the ball shaft; and

[0014] The lower row delivery seat is fixed below the lower flow bin, and a plurality of lower through holes are opened in the lower row delivery seat, and the lower through holes are communicated with the lower flow bin.

[0015] Further, as a preference, the water injection callback component further comprises:

[0016] A plurality of flow-blocking inserts are arranged vertically, each of the flow-blocking inserts is fixedly sleeved on the guide pipe, a corresponding flow inlet hole is opened on the guide pipe, and the cross section of the flow-blocking insert is set to an inverted trapezoidal structure;

[0017] The vibrating liquid guiding device is fixed in the outer tube and is located above the mud conveying pipe.

[0018] Further, as a preference, the vibrating liquid guiding device comprises:

[0019] Upper fixing frame;

[0020] A central shaft is rotatably arranged on the upper fixing frame, and a radial rod is fixed below the central shaft;

[0021] A driving motor is arranged on the upper fixing frame, and an output end of the driving motor is fixed to the central axis;

[0022] A ring frame is fixed above the water accumulation chamber, and a pressure plate is rotatably provided at one end of the radial rod, and the outer circumferential side wall of the pressure plate is in abutment contact with the inner wall of the ring frame; and

[0023] The side springs are arranged in a plurality of groups, and each of the side springs is circumferentially distributed between the mud conveying pipe and the water accumulation chamber.

[0024] Furthermore, as a preference, each main delivery hole in the mud delivery pipe is covered with an elastic rubber cover, and each main delivery hole has an inlet hole and a discharge hole on its side wall. The inlet hole is evenly injected with side water through a liquid pump, and a plurality of embedded blocks are also provided on the side wall of the main delivery hole.

[0025] Furthermore, as a preference, a collecting plate is rotatably provided in the lower row delivery seat.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The mud delivery pipe mainly provided in the present invention is used for the top-down discharge delivery of drilling mud. Among them, the water injection callback component provided in particular can, on the one hand, divert the fine sand in the mud into the guide pipe, reduce the delivery pressure of the mud delivery pipe, improve the delivery efficiency, and thus achieve the pressure reduction effect. On the other hand, the diverted fine sand is mixed into the water source and mixed into the drilling mud at the bottom of the well, fundamentally solving the problem of large equivalent circulating density, and the control efficiency is relatively high.

[0028] 2. The vibrating liquid guiding device also provided in the present invention can further assist the mud guiding and avoid the blockage of the main delivery hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of the present invention;

[0030] Figure 2 It is a structural schematic diagram of the circulating flow chamber in the present invention;

[0031] Figure 3 It is a structural schematic diagram of the water injection callback component in the present invention;

[0032] Figure 4 It is a schematic structural diagram of the vibrating liquid guiding device in the present invention;

[0033] Figure 5 It is a schematic diagram of the structure of the elastic rubber cover in the present invention;

[0034] In the figure: 1. mud conveying pipe; 11. outer tube; 12. upper delivery chamber; 13. valve seat; 14. circulation chamber; 2. water injection callback assembly; 21. water accumulation chamber; 22. water inlet pipe; 23. guide pipe; 24. intermediate frame; 25. flow blocking insert; 26. lower flow chamber; 27. lower delivery seat; 28. collecting plate; 3. vibrating liquid guiding device; 31. upper fixing frame; 32. radial rod; 33. driving motor; 34. ring frame; 35. side spring; 4. elastic rubber cover; 41. inlet hole; 42. insert. DETAILED DESCRIPTION

[0035] See also Figure 1 In an embodiment of the present invention, a continuous drilling equivalent circulation density reduction control device comprises:

[0036] The outer tube 11 is fixed on the drill string and located at the vertical well section;

[0037] A mud conveying pipe 1 is coaxially arranged in the outer tube 11. A mud upward bypass hole is provided on the drill string. The mud upward bypass hole is connected to the mud conveying pipe 1 and is used for circulating and conveying drilling mud from bottom to top.

[0038] A water injection callback component 2 is arranged in the mud delivery pipe 1, and the flow direction of the water injection callback component 2 is opposite to the drilling mud delivery direction in the mud delivery pipe 1; and

[0039] The upper delivery chamber 12 is arranged above the mud conveying pipe 1 .

[0040] In this embodiment, a plurality of main delivery holes are distributed circumferentially in the mud delivery pipe 1, and a circulation bin 14 is symmetrically fixed above and below the mud delivery pipe 1, and the circulation bin 14 is connected with each of the main delivery holes through a joint pipe. A valve seat 13 is fixed below the mud delivery pipe 1, and the mud upward bypass hole is connected with the circulation bin 14 located below through the valve seat 13, that is, the drilling mud is mainly transported upward through the main delivery holes.

[0041] As a preferred embodiment, the water injection callback component 2 includes:

[0042] A water accumulation chamber 21 is provided in the mud conveying pipe 1, and a water inlet pipe 22 is vertically connected to one side of the water accumulation chamber 21;

[0043] A guide pipe 23 is provided corresponding to each of the main delivery holes;

[0044] The lower flow chamber 26 is fixed below the mud delivery pipe 1, and the two ends of the delivery pipe are connected to the water accumulation chamber 21 and the lower flow chamber 26 through a transfer pipe;

[0045] An intermediate frame 24 is fixed at the inner center of the main delivery hole, the guide pipe 23 is connected to the intermediate frame 24, and a ball shaft is fixed to the guide pipe 23, and the guide pipe 23 is rotatably connected to the intermediate frame 24 through the ball shaft; and

[0046] The lower delivery seat 27 is fixed below the lower flow bin 26 , and a plurality of lower through holes are provided in the lower delivery seat 27 , and the lower through holes are communicated with the lower flow bin 26 .

[0047] In this embodiment, the water injection callback component 2 also includes:

[0048] The flow-blocking insert 25 is a plurality of vertically arranged flow-blocking inserts 25, each of which is fixedly sleeved on the guide pipe 23, and the guide pipe 23 is provided with a corresponding flow inlet hole, and the cross section of the flow-blocking insert 25 is set to an inverted trapezoidal structure; in particular, on the one hand, the flow-blocking insert can form multi-stage flow blockage in the main delivery hole, at which time the fine sand in the drilling mud can be filtered out in time and flow into the guide pipe, and the water source transported in the guide pipe can directly transport it to the lower flow bin, thereby reducing the mud delivery pressure in the main delivery hole, improving the delivery efficiency, and achieving a pressure reduction effect. At the same time, the mixed fine sand can be transported to the mud at the bottom of the drilling well again, thereby reducing the equivalent circulating density.

[0049] The vibrating liquid guiding device 3 is fixed in the outer tube 11 and is located above the mud conveying pipe 1 .

[0050] In this embodiment, the vibrating liquid guiding device 3 comprises:

[0051] Upper fixing frame 31;

[0052] A central shaft is rotatably mounted on the upper fixing frame 31, and a radial rod 32 is fixed below the central shaft;

[0053] A driving motor 33 is disposed on the upper fixing frame 31, and an output end of the driving motor 33 is fixed to the central axis;

[0054] The ring frame 34 is fixed above the water accumulation chamber 21, and a pressure plate is rotatably provided at one end of the radial rod 32, and the outer circumferential side wall of the pressure plate is in contact with the inner wall of the ring frame 34; and

[0055] The side springs 35 are arranged in a plurality of groups, each of which is circumferentially distributed between the mud conveying pipe 1 and the water accumulation chamber 21. In particular, the pressure plate can abut against the ring frame and compress the side spring on the corresponding side. At this time, the guide pipe can be installed at an angle relative to the main delivery hole. By driving the central axis to rotate through the driving motor, each guide pipe can form internal agitation with the water accumulation chamber to avoid blockage caused by excessive delivery pressure in the main delivery hole.

[0056] In the present embodiment, the main delivery holes in the mud delivery pipe 1 are covered with elastic rubber covers 4, and the side walls of the main delivery holes are provided with inlet holes 41 and outlet holes. The inlet holes 41 are evenly injected with side water by a liquid pump, and the side walls of the main delivery holes are also provided with a plurality of embedded blocks 42. In particular, the elastic rubber cover can form a soft delivery channel in the main delivery hole. At this time, the inlet holes cooperate with the outlet holes to circulate water, thereby assisting mud transportation and avoiding mud adhesion and blockage.

[0057] As a preferred embodiment, a collecting plate 28 is rotatably disposed in the lower delivery seat 27 .

[0058] Specifically, the drilling mud is transported to the valve seat through the mud upward bypass hole, and is transported from the valve seat to the circulation chamber located below, so that the drilling mud can be transported from bottom to top through the main delivery hole. In the control of equivalent circulating density reduction, water is mainly transported countercurrently through each guide pipe. At this time, the fine sand in the drilling mud can be filtered out and guided to the lower flow chamber, thereby mixing into the downhole mud, fundamentally solving the problem of high equivalent circulating density and achieving high control efficiency.

[0059] What is described above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A continuous drilling equivalent circulation density reduction control device, Features: It includes: An outer tube (11) is fixed on the drill string and located at the vertical well section; A mud conveying pipe (1) is coaxially arranged in the outer tube (11), and a mud upward bypass hole is provided on the drill string. The mud upward bypass hole is connected to the mud conveying pipe (1) and is used for circulating and conveying drilling mud from bottom to top; A water injection callback component (2) is arranged in the mud delivery pipe (1), and the flow direction of the water injection callback component (2) is opposite to the drilling mud delivery direction in the mud delivery pipe (1); and An upper delivery chamber (12) is arranged above the mud delivery pipe (1); The mud delivery pipe (1) has a plurality of main delivery holes distributed in the circumferential direction; The water injection callback component (2) comprises: A water accumulation chamber (21) is arranged in the mud conveying pipe (1), and a water inlet pipe (22) is vertically connected to one side of the water accumulation chamber (21); A guide pipe (23) is arranged corresponding to each of the main delivery holes; A lower flow bin (26) is fixed below the mud delivery pipe (1), and both ends of the delivery pipe are connected to the water accumulation chamber (21) and the lower flow bin (26) through a transfer pipe; An intermediate frame (24) is fixed at the inner center of the main delivery hole, the guide pipe (23) is connected to the intermediate frame (24), and a ball shaft is fixed on the guide pipe (23), and the guide pipe (23) is rotatably connected to the intermediate frame (24) through the ball shaft; and A lower delivery seat (27) is fixed below the lower flow bin (26), wherein a plurality of lower through holes are provided in the lower delivery seat (27), and the lower through holes are connected to the lower flow bin (26); A plurality of flow-blocking inserts (25) are arranged vertically, each of the flow-blocking inserts (25) is fixedly sleeved on the guide pipe (23), a corresponding flow inlet hole is opened on the guide pipe (23), and the cross section of the flow-blocking insert (25) is arranged to be an inverted trapezoidal structure; The vibrating liquid guiding device (3) is fixed in the outer tube (11) and is located above the mud conveying pipe (1).

2. A continuous drilling equivalent circulation density reduction control device according to claim 1, Features: Circulation chambers (14) are symmetrically fixed above and below the mud conveying pipe (1), and the circulation chambers (14) are connected to the main delivery holes through a joint pipe. A valve seat (13) is fixed below the mud conveying pipe (1), and the mud upward bypass hole is connected to the circulation chamber (14) located below through the valve seat (13).

3. A continuous drilling equivalent circulation density reduction control device according to claim 1, Features: The vibrating liquid guiding device (3) comprises: Upper fixing frame (31); A central shaft is rotatably mounted on the upper fixing frame (31), and a radial rod (32) is fixed below the central shaft; A driving motor (33) is arranged on the upper fixing frame (31), and an output end of the driving motor (33) is fixed to the central axis; A ring frame (34) is fixed above the water accumulation chamber (21), and a pressure plate is rotatably provided at one end of the radial rod (32), and the outer circumferential side wall of the pressure plate is in abutment with the inner wall of the ring frame (34); and The side springs (35) are arranged in a plurality of groups, and each of the side springs (35) is circumferentially distributed between the mud conveying pipe (1) and the water accumulation chamber (21).

4. A continuous drilling equivalent circulation density reduction control device according to claim 1, Features: Each main delivery hole in the mud delivery pipe (1) is covered with an elastic rubber cover (4), and the side wall of each main delivery hole is provided with an inlet hole (41) and a discharge hole. The inlet hole (41) is evenly injected with side surrounding water through a liquid pump, and the side wall of the main delivery hole is also provided with a plurality of embedded blocks (42).

5. A continuous drilling equivalent circulation density reduction control device according to claim 1, Features: A current collecting plate (28) is also rotatably arranged in the lower delivery seat (27).

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