CN210217667U - Fluid excitation type infinite circulation well-flushing tool - Google Patents
Fluid excitation type infinite circulation well-flushing tool Download PDFInfo
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- CN210217667U CN210217667U CN201920777043.9U CN201920777043U CN210217667U CN 210217667 U CN210217667 U CN 210217667U CN 201920777043 U CN201920777043 U CN 201920777043U CN 210217667 U CN210217667 U CN 210217667U
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Abstract
The utility model discloses a fluid excitation formula infinite circulation well-flushing tool, including a main section of thick bamboo, top connection, lower clutch, upper mandrel, lower dabber, piston, transposition spring, transposition piece and spacing component, through-hole and the other through-hole of upper mandrel have been seted up to the upper mandrel, blind hole and the other through-hole of lower dabber have been seted up to the lower dabber, have seted up transposition groove and piston by-pass hole on the piston, have seted up the water hole on the main section of thick bamboo, the piston can realize the switching of piston circumferential position through transposition groove and the cooperation of transposition piece, the piston can realize the axial position switching of piston through the cooperation with spacing component to realize the infinite circulation conversion of fluid passage, reaction rate is fast and receive the influence of well inclination little, has solved the problem that the number of times restriction, the needs repeatedly trip to bore reset valve of current circulating valve; compact structure, the mounted position is nimble, can adopt multiple deviational survey mode. The drilling efficiency is improved, and the drilling time is shortened.
Description
Technical Field
The invention belongs to the technical field of downhole tools of oil and gas drilling engineering, and particularly relates to an infinite circulation well-flushing tool which can be controlled by fluid pressure in the processes of well drilling and completion and well repairing and flushing operation.
Background
In the drilling process, the well leakage and overflow are common complex conditions in a well, during the conventional plugging and killing operation, large-particle plugging materials are easy to damage underground instruments, and meanwhile, in the drilling process, if a water hole of a drilling tool is plugged, bypass circulation needs to be quickly established to prevent complex accidents; in the drilling process of large-displacement deep wells and ultra-deep wells, a large amount of detritus beds are often deposited on the steady inclined section and the horizontal section of the deep well, the drilling tool is difficult to clean in time through a conventional small-size drilling tool circulation method, the drilling tool is possibly blocked or the well completion quality is influenced, and a certain turbulent flow is generated in a pump flushing mode under the normal condition, so that the cleaning of a shaft is facilitated. However, the pump speed requirements required for achieving turbulent flow conditions cannot be met for a mud motor and a measurement while drilling tool of a slim hole, and particularly, efficient cleaning of a shaft is difficult to achieve when a highly deviated well and a horizontal well are drilled. Drilling operators often use short lifts, well cleanout operations, bit replacement, and other cleaning operations to address such problems. These methods may be somewhat effective, but require significant time to trip, reducing production efficiency.
Prior patent CN106321013A (single ball throwing type infinite circulation valve, 2017.01.11) discloses a single ball throwing type infinite circulation valve, mainly comprising a housing, a valve piston, and an index control body. The shell is provided with the shell nozzle, and the valve piston and the transposition control main body are arranged in the shell to realize sliding along the axial direction of the shell. The shell, the valve piston and the transposition control main body are internally provided with through holes to form a fluid main flow passage, the valve piston blocks the shell nozzle at a downward valve position to block the communication between the main flow passage and the well annulus, and the valve piston loses the blockage of the shell nozzle at an upward valve position to ensure that fluid can be transferred to the well annulus through the shell nozzle along the main flow passage. The indexing control body has a control slot track coupled to a fixed pin to guide the valve piston to transition between a down position and an up position. The circulating valve is a liquid flow circulating valve which is selectively opened, solves the problems that the opening times of the existing circulating valve is limited, and the valve needs to be reset by repeatedly tripping the drill, improves the drilling efficiency and shortens the drilling time.
Prior patent CN207761600U (a downhole circulating well-flushing tool, 2018.08.24) discloses a downhole circulating well-flushing tool, which can realize free switching between circulating well-flushing and normal drilling operation by putting a switch assembly into use. Circulation overcoat and dabber adopt sliding fit's mode, regard as its state change over switch with the switch ware subassembly, when the dabber locking, circulation channel closes and to realize normal drilling operation, after throwing switch ware body and locking ball, circulation channel opens and to carry out automatic grout, in order to realize automatic well-flushing operation, only need adopt the mode of throwing the switch ware subassembly to realize the switching of normal drilling operation and well-flushing operation, the effectual production time that adopts the tripping operation to consume when having overcome current well-flushing operation, be favorable to the improvement of drilling efficiency.
The two patents achieve the purpose of switching the states of the tools by opening and closing the valve in an infinite circulation mode in different modes, but the infinite circulation valve used for pitching control has obvious defects as various pitching tools. Firstly, an accurate pitching technique is required, and the operation risk is increased due to the fact that the balls are thrown by mistake; secondly, the response speed of the ball-throwing switch is low, the drill column combination cannot be flexibly selected due to the influence of ball throwing, and only MWD (measurement while drilling) can be adopted in the inclination measurement process, so that mechanical inclination measurement cannot be carried out; thirdly, the complexity of the internal structure of the tool is improved due to the special design of the switching device controlled by the pitching, thereby reducing the reliability of the tool and improving the maintenance difficulty of the tool.
Disclosure of Invention
The invention aims to provide an infinite circulation well-flushing tool which utilizes fluid excitation to push a piston to change positions so as to realize the conversion of a fluid channel. The fluid excitation type circulation switch valve has high reaction speed and small influence by a well inclination angle, and the displacement is adjusted to enable the transposition piston to generate different axial displacements under the action of the displacement, so that the problems that the opening times of the conventional circulation valve is limited and the reset valve needs to be repeatedly tripped down are solved; compact structure, the mounted position is nimble, can adopt multiple deviational survey mode. The drilling efficiency is improved, and the drilling time is shortened.
The purpose of the invention is realized by the following technical scheme:
a fluid excitation type infinite circulation well washing tool comprises a main barrel, an upper joint connected with the main barrel through threads, a lower joint connected with the main barrel through threads, an upper mandrel fixed on the upper joint, a lower mandrel fixed on the lower joint, a piston installed inside the main barrel, a transposition spring installed between the lower mandrel and a piston assembly, a transposition member fixed on the main barrel and a limiting element, wherein a through hole and a through hole beside the upper mandrel are formed in the upper mandrel, a blind hole and a through hole beside the lower mandrel are formed in the lower mandrel, a transposition groove and a piston by-pass hole are formed in the piston, a water hole is formed in the main barrel, the piston can be matched with the transposition member through the transposition groove to realize the switching of the circumferential position of the piston, and the piston can be matched with the limiting element to realize the switching of the axial position of the piston.
Preferably, the engagement of the indexing slot with the indexing element provides at least two circumferential positions for the piston and the engagement of the piston with the stop element provides two axial positions for the piston.
Preferably, the upper mandrel bypass hole, the piston bypass hole and the water hole are aligned in at least one of a circumferential position of the piston and an axial position of the piston.
Preferably, the engagement of the indexing slot and the indexing element provides six circumferential positions for the piston, three of which are in simultaneous alignment with the piston bypass bore and the water bore.
As a preferable scheme: piston by pass hole the central axis and water hole the central axis all intersects with the main section of thick bamboo axis, just piston by pass hole the central axis and water hole the central axis is between 10 to 80 for main section of thick bamboo axis contained angle scope.
Preferably, the piston bypass hole is a cylindrical hole with a diameter ranging from 5mm to 35 mm; the water hole is a cylindrical hole, and the diameter of the water hole ranges from 5mm to 35 mm.
Preferably, the piston is a split type piston consisting of an upper piston body and a transposition piston body, the piston bypass hole is formed in the upper piston body, and the transposition groove is formed in the transposition piston body.
Preferably, the main cylinder is provided with an air hole, and the piston can be additionally provided with a buffer structure inside.
Preferably, sealing elements are arranged between the main cylinder and the piston, between the piston and the upper mandrel, and between the piston and the lower mandrel.
Compared with the prior art, the invention has the beneficial effects that:
(1) the infinite circulation well-flushing tool of the invention does not adopt ball-throwing control, but adopts a fluid excitation form to control the opening and closing of the circulation valve, has high reaction speed, small influence by the inclination angle of the well, flexible installation position and can adopt a plurality of inclination measuring modes;
(2) the problems that the opening times of the existing circulating valve are limited and the reset valve needs to be repeatedly tripped down are solved by adopting fluid excitation, enabling the transposition piston to generate different axial displacements and circumferential rotations under the action of displacement by adjusting the displacement of the pump and configuring a special transposition and resetting mechanism
(3) The design of the water spray holes with reverse inclination angles is adopted, and the purpose of positive and negative sand washing and well washing can be realized by matching with a sand washing tool, so that the sand washing and carrying capabilities can be provided;
(4) the upper mandrel and the lower mandrel are fixed relative to the main cylinder, transposition and bypass opening and closing are realized through circumferential rotation and axial movement of the piston, the mandrel does not have jamming, and the transposition structure is high in reliability;
(5) the pressure is sensitive, the opening and closing of the bypass are easy to control, and whether the working mode of the tool is bypassed or straight-through is easy to judge on the ground through the pressure state;
(6) the parts are few, the structure is compact, control mechanisms such as ball seats and switching devices do not need to be designed, and the processing, production and maintenance costs are reduced.
Description of the drawings:
FIG. 1 is a schematic structural diagram of the present invention.
Fig. 2 is a schematic diagram of an operating position in the through state according to an embodiment of the present invention.
FIG. 3 is a schematic diagram of an operating position in the bypass state according to an embodiment of the present invention.
Fig. 4 is a schematic structural diagram of a second embodiment of the present invention.
Fig. 5 is a schematic structural diagram of a transposition piston in the second embodiment of the invention.
Fig. 6 is a schematic structural diagram of a buffer structure in the second embodiment of the present invention, and schematic structural diagrams of the third embodiment and the fourth embodiment.
The specific implementation mode is as follows:
the following non-limiting examples serve to illustrate the invention.
The first embodiment is as follows:
as shown in figures 1 to 3, a fluid excitation type infinite circulation well-flushing tool comprises a main barrel (1), an upper joint (2) connected with the main barrel (1) through threads, a lower joint (3) connected with the main barrel (1) through threads, an upper mandrel (4) fixed on the upper joint (2), a lower mandrel (5) fixed on the lower joint (3), a piston (6) installed in the main barrel (1), a transposition spring (7) installed between the lower mandrel (5) and a piston assembly (5), a transposition piece (8) and a limiting element (9) fixed on the main barrel (1), a through hole (41), an upper mandrel side through hole (42) and a pressure hole (43) are formed on the upper mandrel (4), a blind hole (51) and a lower mandrel side through hole (52) are formed on the lower mandrel, a transposition groove (61) and a piston side through hole (62) are formed on the piston (6), seted up water hole (12) on the main drum (1), piston (6) accessible transposition groove (61) and transposition piece (8) cooperation realize the switching of piston (6) circumferential position, and the axial position switching of piston (6) is realized in the cooperation of piston (6) accessible and spacing component (9), transposition groove (61) with the cooperation of transposition piece (8) does piston (6) provide six circumferential position, on wherein three circumferential position piston by pass hole (62) and last mandrel by pass through-hole (42) and water hole (12) align simultaneously.
The fluid-excited infinite loop well-flushing tool described in this embodiment mainly includes two working states: a straight-through condition and a bypass (well-flushing) condition.
As shown in fig. 2, is the straight-through condition of the present well-flushing tool. Referring to fig. 1, in the pump-on state, the upper end face of the piston (6) is continuously acted by the liquid pressure led out by the upper mandrel pressure hole (43), at the moment, the shifting element (8) is positioned at the through position (shorter than the bypass position and lower than the bypass position) of the shifting groove (61) on the piston (6), and accordingly, the shifting spring (7) is in the through compression state. Limited by the transposition element (8) and the transposition groove (61), the piston bypass hole (62), the main cylinder water hole (12) and the upper mandrel bypass through hole (42) are mutually staggered in the circumferential direction; meanwhile, the piston bypass hole (62), the main cylinder water hole (12) and the upper mandrel bypass through hole (42) are mutually axially staggered under the limitation of the limiting element (9) and the lower end surface of the piston. At the moment, the piston bypass hole (62) is in a staggered state (in the circumferential direction and the axial direction) relative to the main cylindrical water hole (12) and the upper mandrel bypass hole (42), the bypass is closed, liquid flow can only flow out through the upper mandrel through hole (41), then flows into the lower mandrel through the lower mandrel bypass through hole (52), and finally flows out of the lower joint (3) through the lower mandrel blind hole (51), and the state is a through state of the tool.
As shown in figure 3, the well-flushing tool is in a straight-through state. Similarly, in the pump-on state, since the upper end surface of the piston (6) is continuously acted by the hydraulic pressure led out from the upper spindle pressure hole (43), the displacement element (8) is positioned at the bypass position (longer and higher than the straight-through position) of the displacement groove (61) on the piston (6), and accordingly, the displacement spring (7) is in the bypass compression state. Limited by the transposition element (8) and the transposition groove (61), the piston bypass hole (62), the main cylinder water hole (12) and the upper mandrel bypass through hole (42) are circumferentially aligned with each other; meanwhile, the piston bypass hole (62), the main cylinder water hole (12) and the upper mandrel bypass through hole (42) are axially aligned with each other under the restriction of the limiting element (9) and the lower end surface of the piston. Because piston by-pass hole (62) is (circumference and axial) alignment state for main section of thick bamboo water hole (12) and last dabber by-pass hole (42) this moment, the bypass is opened, and the liquid stream only can flow out through going up dabber by-pass hole (42), reaches main section of thick bamboo water hole (12) through piston by-pass hole (62) then, finally forms the jet stream, washes the wall of a well. This state is the bypass state of the tool.
Example two:
as shown in fig. 4 to 6, a fluid excitation type infinite circulation well-flushing tool comprises a main cylinder (1), an upper joint (2) connected with the main cylinder (1) through threads, a lower joint (3) connected with the main cylinder (1) through threads, an upper mandrel (4) fixed on the upper joint (2), a lower mandrel (5) fixed on the lower joint (3), a piston (6) installed inside the main cylinder (1), a transposition spring (7) installed between the lower mandrel (5) and the piston (6), a transposition member (8) and a limiting element (9) fixed on the main cylinder (1), wherein the upper mandrel (4) is provided with a through hole (41), an upper mandrel side through hole (42) and a pressure hole (43), the lower mandrel is provided with a blind hole (51) and a lower mandrel side through hole (52), the piston (6) is a split piston consisting of an upper piston body (63) and a transposition piston body (64), and the piston bypass hole (62) is arranged on the upper piston body (63), and the transposition groove (61) is arranged on the main cylinder (1) of the transposition piston body (64) and is provided with a water hole (12), as shown in figure 5. Piston (6) accessible transposition groove (61) and transposition piece (8) cooperation realize the switching of piston (6) circumferential position, and piston (6) accessible realizes the axial position switching of piston (6) with the cooperation of spacing component (9), transposition groove (61) with the cooperation of transposition piece (8) does piston (6) provide six circumferential position, on wherein three circumferential position piston by pass hole (62) and last mandrel by pass hole (42) and water hole (12) align simultaneously.
In the embodiment, the piston (6) is a split piston consisting of the upper piston body (63) and the transposition piston body (64), so that the processing difficulty and cost can be reduced, and meanwhile, the tool is easy to disassemble, assemble and maintain.
Furthermore, the main cylinder (1) is provided with an air hole (13), a buffer structure (65) can be additionally arranged in the piston (6), and the buffer structure (65) comprises a buffer spring (651), a buffer piston (652) and a spring retainer ring (653).
In this scheme, through set up buffer gear in that the piston is inside, can reduce the impact force of instrument switching in-process piston and the production down between the mandrel, can not only make the working process more stable, smooth, also can avoid reducing because the instrument life-span that the impact leads to.
Further, sealing elements are arranged between the main cylinder (1) and the piston (6), between the piston (6) and the upper mandrel (4), and between the piston (6) and the lower mandrel (5).
EXAMPLE III
As shown in fig. 6, the present embodiment is substantially the same as the second embodiment, and the difference is that: the central axis of the piston bypass hole (62) and the central axis of the water hole (12) are intersected with the axis of the main cylinder, and the central axis of the piston bypass hole (62) and the central axis of the water hole (12) form an included angle range of 20-80 degrees relative to the axis of the main cylinder.
Further, the central axis of the piston bypass hole (62) and the central axis of the water hole (12) form an included angle of 45 degrees relative to the axis of the main cylinder.
Example four
As shown in fig. 6, the present embodiment is substantially the same as the second embodiment, and the difference is that: the piston bypass hole (62) is a cylindrical hole, and the diameter range of the piston bypass hole is between 5mm and 35 mm; the water hole (12) is a cylindrical hole, and the diameter range of the water hole is between 5mm and 35 mm.
Further, the piston bypass hole (62) is a cylindrical hole, and the diameter of the piston bypass hole is 12 mm; the water hole (12) is a cylindrical hole with the diameter of 12 mm.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (9)
1. A fluid-excited endless loop well-flushing tool, comprising: the automatic piston switching device comprises a main barrel (1), an upper joint (2) connected with the main barrel (1) through threads, a lower joint (3) connected with the main barrel (1) through threads, an upper mandrel (4) fixed on the upper joint (2), a lower mandrel (5) fixed on the lower joint (3), a piston (6) installed inside the main barrel (1), a transposition spring (7) installed between the lower mandrel (5) and the piston (6), a transposition element (8) and a limiting element (9) fixed on the main barrel (1), a through hole (41), an upper mandrel side through hole (42) and a pressure hole (43) are formed in the upper mandrel (4), a blind hole (51) and a lower mandrel side through hole (52) are formed in the lower mandrel, a transposition groove (61) and a piston side through hole (62) are formed in the piston (6), a water hole (12) is formed in the main barrel (1), and the piston (6) can be matched with the transposition element (8) to realize the circumferential position switching of the piston (6) through the transposition groove (61) The axial position of the piston (6) can be switched by the piston (6) through the cooperation with the limiting element (9).
2. The fluid-excited endless loop well-flushing tool of claim 1, wherein: the cooperation of the transposition grooves (61) and the transposition elements (8) provides at least two circumferential working positions for the piston (6), and the cooperation of the piston (6) and the limiting element (9) provides two axial working positions for the piston (6).
3. The fluid-excited endless loop well-flushing tool of claim 1, wherein: the upper mandrel bypass opening (42), the piston bypass opening (62), and the water bore (12) are aligned in at least one piston circumferential position and one piston axial position.
4. The fluid-excited endless loop well-flushing tool of claim 1, wherein: the cooperation of the transposition grooves (61) and the transposition elements (8) provides six circumferential positions for the piston (6), and the piston bypass holes (62) are simultaneously aligned with the upper mandrel bypass through holes (42) and the water holes (12) at three of the circumferential positions.
5. The fluid-excited endless loop well-flushing tool of claim 1, wherein: the central axis of the piston bypass hole (62) and the central axis of the water hole (12) are intersected with the axis of the main cylinder, and the central axis of the piston bypass hole (62) and the central axis of the water hole (12) form an included angle range of 20-80 degrees relative to the axis of the main cylinder.
6. The fluid-excited endless loop well-flushing tool of claim 1, wherein: the piston bypass hole (62) is a cylindrical hole, and the diameter range of the piston bypass hole is between 5mm and 35 mm; the water hole (12) is a cylindrical hole, and the diameter range of the water hole is between 5mm and 35 mm.
7. The fluid-excited endless loop well-flushing tool of claim 1, wherein: the piston (6) is a split type piston consisting of an upper piston body (63) and a transposition piston body (64), the piston bypass hole (62) is formed in the upper piston body (63), and the transposition groove (61) is formed in the transposition piston body (64).
8. The fluid-excited endless loop well-flushing tool of claim 1, wherein: an air hole (13) is formed in the main cylinder (1), and a buffer structure (65) can be additionally arranged in the piston (6).
9. The fluid-excited endless loop well-flushing tool of claim 1, wherein: the transposition element (8) is a transposition pin fixed on the main barrel (1), and the limiting element (9) is a limiting pin fixed on the main barrel (1).
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| CN201920777043.9U CN210217667U (en) | 2019-05-28 | 2019-05-28 | Fluid excitation type infinite circulation well-flushing tool |
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| CN201920777043.9U CN210217667U (en) | 2019-05-28 | 2019-05-28 | Fluid excitation type infinite circulation well-flushing tool |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110056321A (en) * | 2019-05-28 | 2019-07-26 | 成都阿斯贝瑞科技有限公司 | A kind of fluid excitation formula Infinite Cyclic well-flushing tool and its application method |
| CN110067523A (en) * | 2019-05-28 | 2019-07-30 | 成都阿斯贝瑞科技有限公司 | A kind of fluid excitation formula Infinite Cyclic well-flushing tool |
-
2019
- 2019-05-28 CN CN201920777043.9U patent/CN210217667U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110056321A (en) * | 2019-05-28 | 2019-07-26 | 成都阿斯贝瑞科技有限公司 | A kind of fluid excitation formula Infinite Cyclic well-flushing tool and its application method |
| CN110067523A (en) * | 2019-05-28 | 2019-07-30 | 成都阿斯贝瑞科技有限公司 | A kind of fluid excitation formula Infinite Cyclic well-flushing tool |
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