ROTARY GUIDING TOOL AND TRANSMISSION DEVICE

Abstract

The present invention provides a rotary guiding tool, comprising: a power unit having an output shaft capable of outputting a torque and an offset driving portion capable of outputting a radial force and/or an axial force; a transmission shaft connected with the output shaft; a support shaft connected with the transmission shaft through a rotation structure, wherein a rotation axis of the rotation structure is perpendicular to an axis of the output shaft, the support shaft has an inner wall defining an accommodating cavity and a forward end and a rearward end formed at both ends of the accommodating cavity, a rotation center of the rotation structure is located in the accommodating cavity, and the rearward end of the support shaft is capable of being driven by the radial force output by the offset driving portion; and a drill bit having a drill bit tail end, wherein the drill bit and the forward end of the support shaft are connected to the drill bit tail end. According to the present invention, the rotary guiding tool may improve the whipstocking ability of the drilling tool, and reduce the energy consumption of driving the drilling tool.

Claims

1-10. (canceled)

11. A rotary guiding tool, wherein, comprising: a power unit having an output shaft capable of outputting a torque and an offset driving portion capable of outputting a radial force and/or an axial force; a transmission shaft connected with the output shaft; a support shaft connected with the transmission shaft through a rotation structure, a rotation axis of the rotation structure is perpendicular to an axis of the output shaft, the support shaft has an inner wall defining an accommodating cavity, and a forward end and a rearward end formed at both ends of the accommodating cavity, a rotation center of the rotation structure is located in the accommodating cavity, and the rearward end of the support shaft is capable of being driven by the radial force output by the offset driving portion; and a drill bit having a drill bit tail end, the drill bit and the forward end of the support shaft are connected to the drill bit tail end.

12. The rotary guiding tool of claim 11, wherein, the rotation structure comprises a rotation joint that forms a spherical pair with the support shaft, and a flexible member that passes through the rotation joint and is connected with the support shaft.

13. The rotary guiding tool of claim 12, wherein, the rotation joint comprises a first protrusion proximal to the forward end of the support shaft and having a first truncated spherical surface portion, the support shaft has a first groove, and the first groove and the first protrusion cooperate at the first truncated spherical surface portion to form a spherical pair.

14. The rotary guiding tool of claim 13, wherein, a surface hardness of the first groove is greater than a surface hardness of the first protrusion.

15. The rotary guiding tool of claim 13, wherein, the rotation joint further comprises a pair of connection keys arranged with a central axis of rotation of the transmission shaft as a symmetrical axis, the pair of connection keys are mounted on the rotation joint, and the support shaft is formed with a key slot cooperating with the connection keys; the connection key has a second protrusion, and a surface of the second protrusion is of a truncated cylindrical shape with a rotation axis of the rotation structure as a central axis.

16. The rotary guiding tool of claim 13, wherein, the rotation joint further comprises a third protrusion formed at an end, distal from the forward end of the support shaft, of the connection key, the third protrusion has a second truncated spherical surface portion that is concentric with the first truncated spherical surface portion, the support shaft has a third groove, and the third groove and the third protrusion cooperate at a second cross section spherical surface portion to form a spherical pair.

17. The rotary guiding tool of claim 14, wherein, the rotation joint further comprises a third protrusion formed at an end, distal from the forward end of the support shaft, of the connection key, the third protrusion has a second truncated spherical surface portion that is concentric with the first truncated spherical surface portion, the support shaft has a third groove, and the third groove and the third protrusion cooperate at a second cross section spherical surface portion to form a spherical pair.

18. The rotary guiding tool of claim 15, wherein, the rotation joint further comprises a third protrusion formed at an end, distal from the forward end of the support shaft, of the connection key, the third protrusion has a second truncated spherical surface portion that is concentric with the first truncated spherical surface portion, the support shaft has a third groove, and the third groove and the third protrusion cooperate at a second cross section spherical surface portion to form a spherical pair.

19. The rotary guiding tool of claim 12, wherein, an end of the flexible member is mounted on a fixed portion of the support shaft, the other end of the flexible member is supported by a support portion of the transmission shaft, and the rotation center of the rotation structure is located between the fixed portion and the support portion.

20. The rotary guiding tool of claim 13, wherein, an end of the flexible member is mounted on a fixed portion of the support shaft, the other end of the flexible member is supported by a support portion of the transmission shaft, and the rotation center of the rotation structure is located between the fixed portion and the support portion.

21. The rotary guiding tool of claim 14, wherein, an end of the flexible member is mounted on a fixed portion of the support shaft, the other end of the flexible member is supported by a support portion of the transmission shaft, and the rotation center of the rotation structure is located between the fixed portion and the support portion.

22. The rotary guiding tool of claim 15, wherein, an end of the flexible member is mounted on a fixed portion of the support shaft, the other end of the flexible member is supported by a support portion of the transmission shaft, and the rotation center of the rotation structure is located between the fixed portion and the support portion.

23. The rotary guiding tool of claim 11, wherein, further comprising an annular pressure balance portion connecting the inner wall of the support shaft and an outer wall of the transmission shaft, a portion of the inner wall of the support shaft, a portion of the outer wall of the transmission shaft and an inner surface of the pressure balance portion jointly define a medium cavity.

24. The rotary guiding tool of claim 12, wherein, further comprising an annular pressure balance portion connecting the inner wall of the support shaft and an outer wall of the transmission shaft, a portion of the inner wall of the support shaft, a portion of the outer wall of the transmission shaft and an inner surface of the pressure balance portion jointly define a medium cavity.

25. The rotary guiding tool of claim 13, wherein, further comprising an annular pressure balance portion connecting the inner wall of the support shaft and an outer wall of the transmission shaft, a portion of the inner wall of the support shaft, a portion of the outer wall of the transmission shaft and an inner surface of the pressure balance portion jointly define a medium cavity.

26. The rotary guiding tool of claim 14, wherein, further comprising an annular pressure balance portion connecting the inner wall of the support shaft and an outer wall of the transmission shaft, a portion of the inner wall of the support shaft, a portion of the outer wall of the transmission shaft and an inner surface of the pressure balance portion jointly define a medium cavity.

27. The rotary guiding tool of claim 15, wherein, further comprising an annular pressure balance portion connecting the inner wall of the support shaft and an outer wall of the transmission shaft, a portion of the inner wall of the support shaft, a portion of the outer wall of the transmission shaft and an inner surface of the pressure balance portion jointly define a medium cavity.

28. The rotary guiding tool of claim 11, wherein, a shortest distance between the rotation center and the drill bit tail end is not greater than 3.5 times of a maximum radial dimension of the support shaft.

29. A transmission device, separately connected to: a power unit having an output shaft capable of outputting a torque and an offset driving portion capable of outputting a radial force; a drill bit having a drill bit tail end; wherein, the transmission device comprises: a transmission shaft coaxially connected with the output shaft; a support shaft coaxially connected with the transmission shaft through a rotation structure, a rotation axis of the rotation structure is perpendicular to an axis of the output shaft, the support shaft has an accommodating cavity and a forward end and a rearward end formed at both ends of the accommodating cavity, a rotation center of the rotation structure is located in the accommodating cavity, and the rearward end of the support shaft is capable of being driven by the radial force output by the offset driving portion, and the forward end and the drill bit are coaxially connected to the drill bit tail end.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0047] The drawings described herein are intended to provide a further understanding of the invention, and are intended to be a part of this invention. The schematic embodiments of this invention and their descriptions are used to interpret this invention and do not constitute an undue limitation of this invention. In the drawings:

[0048] FIG. 1 depicts a structural composition schematic diagram of a rotary guiding tool according to an embodiment of the invention.

[0049] FIG. 2 depicts a structural composition schematic diagram of the transmission device of the rotary guiding tool according to an embodiment of the invention.

[0050] FIG. 3 depicts a structural schematic diagram of the transmission shaft of the rotary guiding tool according to an embodiment of the invention.

DETAIL DESCRIPTIONS OF EMBODIMENTS

[0051] In order to explain the overall concept of the present invention more clearly, the following detailed description is illustrated by way of example with reference to the attached drawings.

[0052] It should be noted that in the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described here. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0053] In addition, in the descriptions of the present invention, it should be understood that the terms, such as “center”, “upper”, “lower”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer”, “axial”, “radial”, “circumferential”, indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0054] In the present invention, unless otherwise clearly specified and limited, the terms, such as “installation”, “interconnection”, “connection”, “fixed” should be understood in a broad sense, for example, the connection may be a fixed connection, a detachable connection or an integrated connection; and the connection may be a direct connection or an indirect connection through an intermediate medium; and the connection may be the communication between two elements or the interaction between two elements. However, the indication of direct connection means that the connected two main bodies do not build a connection relationship through a transition structure, but are only connected through a connection structure to form a whole. The ordinary artisans concerned may understand the specific meaning of terms in this disclosure according to specific circumstance.

[0055] In the present invention, unless otherwise specified and defined, the first feature is “on” or “under” the second feature means that the first and second features may be in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, descriptions with reference to the terms, such as “one embodiment”, “some embodiments”, “examples”, “specific examples”, or “some examples”, mean that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present invention. In the present specification, the schematic representation of the above terms does not necessarily mean the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples.

[0056] As shown in FIG. 1, in an embodiment of the present invention, a structural schematic diagram of a down hole drilling tool assembly is described, wherein a rotary guiding tool comprises a drill bit 110, a transmission device 120 and a power unit 130. In addition, the assembly also includes an MWD unit 140 that cooperates with the rotary guiding tool.

[0057] For each part of the structure, the drill bit 110 is used for drilling, cutting and destroying the rock formation, and plays the role of rock breaking, and is directly connected with the transmission device 120; the power unit assembly 130 provides a driving force for the transmission device 120, and the driving force can be a radial or axial force and also provides a torque that drives the drill to rotate. The MWD unit 140 is a conventionally configured monitoring device that can measure and monitor well bore trajectory parameters and rotating guiding tool's working progress in a real time, and is equipped with a mud pulse generator or electromagnetic wave transmission unit to transmit the down hole useful information to the surface operating system.

[0058] FIG. 2 is a schematic diagram of the structural assembly of the transmission device 120. The transmission device comprises a transmission shaft and the support shaft, and the transmission shaft extends into the support shaft and the transmission shaft and the support shaft are connected by a rotation joint, which can transmit torque between the transmission shaft and the support shaft, and the transmission shaft and the support shaft can rotate relatively through the rotation joint, to change the direction of the drill bit to adjust the inclination and azimuth angles.

[0059] As shown in the figure, the support shaft includes an upper support shaft 1211 and a lower support shaft 1201. The lower support shaft 1201 is connected to the drill bit. The transmission shaft 1202 and the connection key 1203 are the main power transmission components, the shapes of which are shown in FIG. 3. The connection key 1203 will cooperate with the key slot formed in the lower support shaft 1201 and having the accommodating cavity to transmit torque, and the connection key will also cooperate with the key slot to form a rotating pair. As shown in the figure, the two pairs of connection keys are connected to the rotation joint of the front section of the transmission shaft through a hole column structure. When the lower support shaft rotates relative to one of the pairs of connection keys, a center shaft of the other pair of connection keys with a hole column connection structure is used as the rotation shaft. The center of the hole column connection of each connection key meets the rotation center of the rotation joint.

[0060] The transmission shaft 1202 is fixedly connected with the power unit through a threaded structure, so that it can withstand the torque and driving force provided by the power unit.

[0061] Jacking member 1204 and the flexible wear-resistant sleeve 1205 are used to seal and isolate the mud passage in the device from the outer annular mud passage. Meanwhile, the jacking member is fixedly connected to the lower support shaft, which can be regarded as a part of the support shaft, that is, one end of the flexible wear-resistant sleeve is fixedly connected to the support shaft. The other end of the flexible wear-resistant sleeve is supported on the inner hole of the transmission shaft and sealed by a sealing structure.

[0062] There is a spherical pair structure between the wear-resistant sleeve 1206 and the transmission shaft 1202, thereby forming a universal transmission node. The structure of the spherical pair is shown in the figure, including a front-end spherical pair and a rear-end spherical pair. Specifically, the rotation joint includes a first protrusion with a first truncated spherical surface portion proximal to the forward end of the support shaft. The support shaft has a first groove, and the first groove and the first protrusion cooperate at the first truncated spherical surface portion to form the front-end spherical pair. The rotation joint further includes a third protrusion formed at one end of the forward end of the connecting key distal from the support shaft. The third protrusion has a second truncated spherical surface portion that is concentric with the first truncated spherical surface portion. The support shaft has a third groove, and the third groove and the third protrusion cooperate at the second truncated spherical surface portion to form the rear-end spherical pair.

[0063] The anti-dropping member 1207 is mainly used to prevent the transmission device from separating from the drilling tool assembly during the lifting process of the rotary guiding tool. Specifically, it is to prevent the transmission shaft from separating from the support shaft.

[0064] The rotation joint is immersed in the closed hydraulic oil filled in the medium cavity. The hydraulic oil must be vacuumed before working. The oil circuit system has a sleeve-shaped pressure balance member 1208 with the two ends connected to the transmission shaft and the support shaft, respectively, which may be a high temperature resistant rubber member, but also can be a metal bellows or other type of balance structure. It can adaptively balance the external mud pressure to automatically adapt to the underground high temperature and high pressure environment.

[0065] The oil filling plugs 1209 and 1212 are used to seal the oil filling ports of the medium cavity containing the hydraulic oil, and the oil filling plugs 1209 and 1212 are removed after the tool is assembled. Then the external vacuum oil filling device is connected to complete the oil filling operation. The sealing members 1213 and 1214 are high-temperature static sealing structures, such as O-rings, to achieve a sealing function.

[0066] In the actual working process, for the upper support shaft 1211 and the power unit, the power unit applies a force to the upper support shaft 1211 through a suitable force application structure. This force can be a radial force or an axial force. The bias around the rotation structure is generated under the action of the force, so that a center line of the rotary guiding tool and an axis of the drilling tool assembly generate an offset angle. Meanwhile, under the action of the fulcrum, the force borne by the upper support shaft will be directly transmitted to the drill bit part through the lower support shaft, and finally the entire drill tool assembly will generate a whipstocking rate in a specified direction. Since the force-bearing part is only the transmission device, rather than the entire drill tool assembly, this type of rotary guiding structure reduces unnecessary energy consumption, and meanwhile the whipstocking ability will be improved.

[0067] The parts of the present invention that are not described in detail belong to the common knowledge of those skilled in the art.