Drilling tool face measuring apparatus and measuring method

Abstract

A drilling tool face measuring apparatus, for connection with a drill bit, includes: an outer cylinder configured to rotate synchronously with the drill bit; a coded disk fixedly arranged inside the outer cylinder and including a plurality of coded holes; a valve block configured to rotate coaxially, and open and close different coded holes at various rotational positions; and an gravity-oriented sensor rotatably arranged inside the outer cylinder and connected to the valve block, wherein a center of gravity of the gravity-oriented sensor does not coincide with an axis of rotation of the valve block, and the gravity-oriented sensor is configured to drive the valve block to rotate synchronously about the axis of rotation of the valve block, so that the gravity-oriented sensor causes the valve block to maintain an orientation. A method for measuring a drilling tool angle uses the drilling tool face measuring apparatus.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is based on and claims priority to China Patent Application No. 202310050113.1, 202310050112.7, 202310050117.X, 202310050115.0, 202310050118.4 and 202310050119.9 filed on Feb. 1, 2023, the disclosures of which are incorporated by reference herein in their entireties.TECHNICAL FIELD

[0002] The present disclosure belongs to the field of oil and gas drilling technology, in particular to a drilling tool face measuring apparatus and a measuring method using the drilling tool face measuring apparatus.BACKGROUND

[0003] With the development of oil-gas exploration and development and the emphasis on deep well and ultra-deep well drilling technology, the explorations of deep well and ultra-deep well are increasing at present, and the proportion of deep wells in completion wells is increasing every year. The multi-well drilling depth is more than 8000 m, and the measured bottom-hole temperature is mostly above 200° C. In some areas, the geothermal gradient is high (3.3-3.82° C. / 100 m), the deep well drilling temperature is high, and the design predicted bottom-hole temperature is above 230° C. However, during the process of deep well construction, no matter whether the high-temperature rotation pulse MWD or the high-temperature pulse MWD of the existing drilling company is used, since these drilling tools are mostly in the structural form of an electronic element, the actual tolerance temperature is mostly below 180° C., and the instrument data is unstable and fail to work normally under the working condition that the bottom-hole temperature is too high, which causes a serious influence on drilling construction. Therefore, the exploration and development of oil and gas resources is encountered with the problem of directional drilling in ultra-high temperature strata.

[0004] The development and utilization of hot dry rock resources are developing rapidly. At present, the temperature of hot dry rock resources with a favorable development effect in the related art is above 200° C., and directional well construction is often used.

[0005] Therefore, the drilling work of deep well and ultra-deep well as well as the development and utilization of dry hot rock resources, are both encountered with the problem that the existing measurement-while-drilling tools fail to work normally under high-temperature working conditions.SUMMARY

[0006] In view of the technical problem described above, the present disclosure aims to propose a drilling tool face measuring apparatus, which uses a purely mechanical structure, which can work normally under high-temperature working conditions.

[0007] The present disclosure also provides a measuring method using the drilling tool face measuring apparatus, which can work normally under high-temperature working conditions.

[0008] In one aspect of the present disclosure, a drilling tool face measuring apparatus for connection with a drill bit is provided, wherein the drilling tool face measuring apparatus includes: an outer cylinder configured to rotate synchronously with the drill bit; a coded disk fixedly arranged inside the outer cylinder and having a plurality of coded holes axially penetrating through the coded disk and arranged in a circumferential direction; a valve block configured to rotate coaxially relative to the coded disk, and open and close different coded holes among the plurality of coded holes at various rotational positions relative to the coded disk; and a gravity-oriented sensor rotatably arranged inside the outer cylinder and connected to the valve block, wherein a center of gravity of the gravity-oriented sensor does not coincide with an axis of rotation of the valve block, and the gravity-oriented sensor is configured to drive the valve block to rotate synchronously about the axis of rotation of the valve block, so that the gravity-oriented sensor causes the valve block to maintain an orientation relative to the axis of rotation of the valve block under action of gravity.

[0009] In some embodiments, the plurality of coded holes are arranged at equal angular intervals on the coded disk along a circumferential direction, and cross-sectional dimensions of the plurality of coded holes are different.

[0010] In some embodiments, the gravity-oriented sensor includes a rotary shaft connected with the valve block, and an outer wall of the rotary shaft is provided with an eccentric weight block, which causes that the axis of rotation of the gravity-oriented sensor does not coincide with the center of gravity.

[0011] In some embodiments, both ends of the rotary shaft are connected with the outer cylinder through a bearing, and the outer cylinder is internally provided with a bearing seat assembly for mounting the bearing, and the bearing seat assembly is provided with a plurality of first flow holes uniformly arranged in a circumferential direction, so that the first flow holes are located circumferentially outside the bearing.

[0012] In some embodiments, the outer cylinder is further internally provided with a fixing ring fixedly connected with the bearing seat assembly, the fixing ring is arranged on one side of the bearing seat assembly away from the eccentric weight block, and the fixing ring is provided with a plurality of second flow holes corresponding to the first flow holes, the plurality of second flow holes are uniformly arranged in a circumferential direction, and a cross-sectional dimension of the second flow holes are larger than that of the first flow holes.

[0013] In some embodiments, the bearing seat assembly is internally provided with a radial bearing and a thrust bearing, the thrust bearing is closer to the eccentric weight block than the radial bearing, and a bearing retaining ring is arranged between the thrust bearing and the radial bearing.

[0014] In some embodiments, an upper connector is arranged at one end of the outer cylinder away from the drill bit, and a fairing cap is arranged at one end of the rotary shaft away from the drill bit, one end of the fairing cap away from the rotary shaft is provided to be a spherical surface, and a drilling fluid channel is formed between the fairing cap and the upper connector.

[0015] In some embodiments, the gravity-oriented sensor is provided with a mandrel assembly including: a rotary shaft; and an eccentric weight block fixedly arranged on the rotary shaft, wherein the eccentric weight block causes the center of gravity of the gravity-oriented sensor to deviate from an axis of rotation of the rotary shaft.

[0016] In some embodiments, the gravity-oriented sensor is provided with a mandrel assembly including: a rotary shaft; a protective shell coaxially sleeved on the rotary shaft; and an eccentric weight block fixedly arranged on the rotary shaft, wherein the eccentric weight block is arranged between the rotary shaft and the protective shell, and the eccentric weight block causes the center of gravity of the unbalanced sensor to deviate from an axis of rotation of the rotary shaft.

[0017] In some embodiments, an annular blind end is arranged at an inner side of an end of the protective shell, an end of the eccentric weight block axially abuts against the annular blind end, and the annular blind end is provided with a plurality of mounting pins for connection with the eccentric weight block, the plurality of mounting pins are uniformly arranged in a circumferential direction.

[0018] In some embodiments, the rotary shaft is coaxially provided with two cover plates arranged at both ends of the eccentric weight block respectively, and outer ends of the cover plates axially extend towards the eccentric weight block, so that an outer wall of the eccentric weight block radially abuts against the cover plates, and the cover plates axially abut against the annular blind end of the protective shell to prevent the mounting pins from disengagement.

[0019] In some embodiments, the eccentric weight block includes two semi-cylinders with equal volumes enclosing the rotary shaft, one of which is formed of a first material, and the other is formed of a second material, and a density of the second material is greater than that of the first material.

[0020] In some embodiments, the rotary shaft is coaxially provided with two cover plates arranged at both ends of the eccentric weight block respectively, and outer ends of the cover plates axially extend towards the eccentric weight block, so that an outer wall of the eccentric weight block radially abuts against the cover plate.

[0021] In some embodiments, the rotary shaft is provided with a second boss for cooperating with the cover plate, the cover plate is coaxially sleeved on the second boss through a second flat key located proximate to the eccentric weight block.

[0022] In some embodiments, a thickness of the cover plate is less than that of the second boss.

[0023] In some embodiments, a clamping block is fixedly connected to the outer wall of the rotary shaft, and the eccentric weight block is provided with a clamping groove for clamping with the clamping block.

[0024] In some embodiments, each of the eccentric weight blocks corresponds to one of the clamping blocks presenting a strip shape and extending along a generatrix of the rotary shaft.

[0025] In some embodiments, the clamping blocks are divided into three sections with an equal length and arranged on the outer wall of the rotary shaft at intervals along an axial direction.

[0026] In some embodiments, the clamping block is fixedly connected with the rotary shaft by means of bolt connection or integral formation.

[0027] In some embodiments, the drilling tool face measuring apparatus includes a plurality of gravity-oriented sensors connected with each other through a mandrel connector, and a straight line passing through centers of gravity of the plurality of gravity-oriented sensors is parallel to axes of rotation of the plurality of gravity-oriented sensors.

[0028] In some embodiments, the mandrel connector includes a sleeve joint and a polish rod joint, a ring gear for mated plugging is arranged at one end where the sleeve joint and the polish rod joint are connected with each other, a positioning cylinder is arranged at an edge of the sleeve joint, and a positioning rod for plugging with the positioning cylinder is arranged at an edge of the polish rod joint.

[0029] In some embodiments, the sleeve joint and the polish rod joint are in a cylindrical shape, and the ring gear includes a plurality of first meshing teeth arranged on an end face of the sleeve joint in a circumferential direction and a second meshing teeth arranged at an end face of the polish rod joint in a circumferential direction.

[0030] In some embodiments, a shape of a gap between adjacent first meshing teeth matches a shape of the second meshing teeth.

[0031] In some embodiments, the numbers of the first meshing teeth and the second meshing teeth are both three.

[0032] In some embodiments, sections of the first meshing teeth and the second meshing teeth are fan-shaped, and fan-shaped angles of the first meshing teeth and the second meshing teeth are 60 degrees.

[0033] In some embodiments, a stepped hole for connection with the rotary shaft is arranged at one end of the sleeve joint and the polish rod joint away from the ring gear.

[0034] In some embodiments, the positioning cylinder is fixedly connected with the sleeve joint through a first connection block, and the positioning rod is fixedly connected with the polish rod joint through a second connection block.

[0035] In some embodiments, the cylinder wall of the positioning cylinder is provided with an open slot which extends along a generatrix direction and through which the second connection block passes.

[0036] In some embodiments, the drilling tool face measuring apparatus includes: a pulse generator including: a first housing, the coded disk and the valve block; wherein the first housing is a part of the outer cylinder.

[0037] In some embodiments, an inner wall of the outer cylinder is provided with a plurality of mounting grooves arranged along a circumferential direction and extending along an axial direction, the coded disk is provided with a plurality of mounting teeth in one-to-one correspondence with the plurality of mounting grooves, and the coded disk is fixed inside the outer cylinder by embedding the plurality of mounting teeth into the plurality of mounting grooves.

[0038] In some embodiments, the outer cylinder is further internally provided with a key sleeve and a retaining ring, an outer wall of the key sleeve is provided with a plurality of mounting teeth in one-to-one correspondence with the plurality of mounting grooves, one end of the coded disk abuts against an end of the mounting grooves, the other end of the coded disk abuts against the key sleeve, the retaining ring is arranged at one end of the key sleeve away from the coded disk in an abutting manner, and the retaining ring is fixedly connected with the outer cylinder.

[0039] In some embodiments, a wear-resistant column is coaxially arranged at an end face of the coded disk, and a wear-resistant groove for mated rotationally with the wear-resistant column is arranged at the axis of rotation of the valve block.

[0040] 3 In some embodiments, the valve block connects the gravity-oriented sensor through a gravity valve stem and a valve stem joint, the gravity valve stem is movable along an axial direction relative to the valve stem joint, and an elastic member is provided between the gravity valve stem and the valve stem joint.

[0041] In some embodiments, the valve block is fixedly connected with the gravity valve stem, one end of the valve stem joint adjacent to the gravity valve stem is provided with a stepped hole having a first hole section and a second hole section, the second hole section is located inside the first hole section, and a cross-sectional dimension of the first hole section is larger than that of the second hole section, the first hole section is connected with the gravity valve stem through a flat key, and the elastic member includes a spring arranged in the second hole section, and both ends of the spring abut against the gravity valve stem and the valve stem joint respectively.

[0042] In some embodiments, one end of the valve stem joint away from the gravity valve stem is provided with a square hole for connection with the gravity-oriented sensor, and the valve stem joint is provided with a threaded hole penetrating along a radial direction, and the threaded hole intersects with the square hole.

[0043] In some embodiments, fan-shaped angles of the coded holes are equal, and a fan-shaped angle of a coded hole of n coded holes is 360° / (2n), and the valve blocks are fan-shaped, and an angle of a valve block of the valve blocks is equal to the fan-shaped angle of the coded hole.

[0044] In some embodiments, the gravity-oriented sensor includes: a second housing; a mandrel assembly coaxially and rotatably arranged in the second housing, wherein the mandrel assembly is configured such that the center of gravity does not coincide with the axis of rotation, and an annular space is provided between the mandrel assembly and the second housing; and a bearing seat assembly arranged in the second housing, wherein the bearing seat assembly is arranged at both ends of the mandrel assembly, and the bearing seat assembly is provided with a first flow hole penetrating radially.

[0045] In some embodiments, the bearing seat assembly is internally provided with a stepped hole for mounting a bearing, and one open end of the stepped hole faces towards the mandrel assembly.

[0046] In some embodiments, both ends of the mandrel assembly are provided with a sealing plate cooperating with the bearing seat assembly to seal the stepped hole of the bearing seat assembly, thereby protecting a bearing in the bearing seat assembly.

[0047] In some embodiments, a sealing ring configured to coaxially rotate and seal is arranged on a mating surface of the sealing plate and the bearing seat assembly, and a size of the sealing ring is larger than that of the stepped hole of the bearing seat assembly.

[0048] In some embodiments, the number of the first flow holes is three, the first flow holes are uniformly arranged on the bearing seat assembly in a circumferential direction, and a size of a circle surrounded by the first flow holes is larger than that of the sealing ring.

[0049] In some embodiments, the first flow hole is provided fan-shaped.

[0050] In some embodiments, a fixing ring is fixedly arranged at one end of the bearing seat assembly away from the mandrel assembly, and the fixing ring is fixedly connected with the second housing.

[0051] In some embodiments, a second flow hole corresponding to the first flow hole is arranged on the fixing ring to radially penetrate through the fixing ring.

[0052] In some embodiments, the second flow hole is provided fan-shaped, and a fan-shaped angle of the second flow hole is larger than that of the first flow hole.

[0053] In some embodiments, the bearing seat assembly at an upper end of the mandrel assembly is internally provided with a spherical roller bearing, and the bearing seat assembly at an lower end of the mandrel assembly is internally provided with a radial bearing and a thrust bearing.

[0054] In another aspect of the present disclosure, a method for measuring a drilling tool angle by using the drilling tool face measuring apparatus according to any one of the above-described embodiments is provided. The method includes the following steps: connecting the drilling tool face measuring apparatus with a drilling tool combination, and calibrating a directional bent sub of the drilling tool combination with the drilling tool face measuring apparatus and then performing running in hole; pumping for circulation, and maintaining a stable displacement at a constant predetermined value; driving the drilling tool to rotate for one turn, so that the coded disk rotates for one turn relative to the valve block to obtain a pressure pulse signal; collecting and analyzing the pressure pulse signal, judging an included angle between a lower side of a wellbore inclination and a reference plane of the drilling tool, so as to implement measuring a current tool face angle; causing the rotary drilling tool to continue to rotate for one turn, and performing double check measurement; and rotating the drilling tool to cause the tool face swing to a specified position according to a measurement result.

[0055] In some embodiments, the drilling tool face measuring method further includes the following steps: designing a pressure pulse and structural parameters of the coded disk according to the orifice flow theory; calculating an eccentric torque, a bearing friction and a coded disk friction of the gravity-oriented sensor under different shapes, different lengths and different materials; and simulating a dynamics response of the gravity-oriented sensor, and simulating a waveform of the pressure pulse, so as to select an optimal coding of the coded disk.

[0056] Compared with the related art, the advantages of the present application are as follows.

[0057] The present disclosure uses a purely mechanical structure to replace the measurement-while-drilling tool for measuring the tool face using an electronic element in the prior art, so that its endurable temperature is much higher than that of the measurement-while-drilling tool using an electronic element in the prior art, so as to overcome the problem that the measurement-while-drilling tool in the related art fail to work normally under high-temperature working conditions.

[0058] The coded disk of the present disclosure rotates along with the drill bit, a plurality of coded holes are circumferentially arranged on the coded disk, and the valve block for blocking the coded holes always faces towards the lower side of the wellbore inclination under the action of the gravity-oriented sensor, so that the valve block can rotate relative to the coded holes and generate different pressure pulses. According to the pressure pulse, it is possible to judge the angle of the tool face, so as to adjust the drilling direction.BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The present invention will be described below with reference to the accompanying drawings.

[0060] FIG. 1 is a schematic view of a drilling tool face measuring apparatus according to some embodiments of the present disclosure;

[0061] FIG. 2 is a schematic view of a pulse generator according to some embodiments of the present disclosure;

[0062] FIG. 3a is a schematic view of a coded disk according to some embodiments of the present disclosure;

[0063] FIG. 3b is a schematic view of a coded disk according to some embodiments of the present disclosure;

[0064] FIG. 3c is a schematic view of a coded disk according to some embodiments of the present disclosure;

[0065] FIG. 4a is a schematic view of a front view structure of a valve block according to some embodiments of the present disclosure;

[0066] FIG. 4b is a schematic view of a left view structure of a valve block according to some embodiments of the present disclosure;

[0067] FIG. 4c is a schematic view of a left view structure of a valve block according to other embodiments of the present disclosure;

[0068] FIG. 5 is a schematic structural view of a first housing according to some embodiments of the present disclosure;

[0069] FIG. 6 is a schematic cross-sectional view of a key sleeve according to some embodiments of the present disclosure;

[0070] FIG. 7 is a schematic view of a gravity valve stem according to some embodiments of the present disclosure;

[0071] FIG. 8 is a schematic view of a valve stem joint according to some embodiments of the present disclosure;

[0072] FIG. 9 is a schematic view of an internal structure of a gravity-oriented sensor according to some embodiments of the present disclosure;

[0073] FIG. 10 is a schematic view of a rotary shaft and a clamping block of a gravity-oriented sensor according to some embodiments of the present disclosure;

[0074] FIG. 11 is a schematic view of a rotary shaft and a clamping block of a gravity-oriented sensor according to other embodiments of the present disclosure;

[0075] FIG. 12a is a schematic cross-sectional view of an eccentric weight block according to some embodiments of the present disclosure;

[0076] FIG. 12b is a schematic view of an end surface of an eccentric weight block according to some embodiments of the present disclosure;

[0077] FIG. 13 is a schematic view of a gravity-oriented sensor according to some embodiments of the present disclosure;

[0078] FIG. 14a is a schematic side view of a cover plate according to some embodiments of the present disclosure;

[0079] FIG. 14b is a schematic cross-sectional view of an eccentric weight block according to some embodiments of the present disclosure;

[0080] FIG. 15a is a schematic sectional view of a protective shell according to some embodiments of the present disclosure;

[0081] FIG. 15b is a schematic side view of a protective shell according to some embodiments of the present disclosure;

[0082] FIG. 16 is a schematic view of a connection structure between a rotary shaft and a second housing according to some embodiments of the present disclosure;

[0083] FIG. 17a is a schematic view of an end surface of a first bearing seat according to some embodiments of the present disclosure;

[0084] FIG. 17b is a schematic view of a sectional structure of a first bearing seat according to some embodiments of the present disclosure;

[0085] FIG. 18a is a schematic view of an end surface of a fixing ring according to some embodiments of the present disclosure;

[0086] FIG. 18b is a schematic view of a sectional structure of a fixing ring according to some embodiments of the present disclosure;

[0087] FIG. 19a is a schematic view of an end surface of a second bearing seat according to some embodiments of the present disclosure;

[0088] FIG. 19b is a schematic view of a sectional structure of a second bearing seat according to some embodiments of the present disclosure;

[0089] FIG. 20a is a schematic view of a three-dimensional structure of a sealing plate according to some embodiments of the present disclosure;

[0090] FIG. 20b is a schematic view of a sectional structure of a sealing plate according to some embodiments of the present disclosure;

[0091] FIG. 21a is a schematic view of an end surface of a sealing cover according to some embodiments of the present disclosure;

[0092] FIG. 21b is a schematic view of a sectional structure of a sealing cover according to some embodiments of the present disclosure;

[0093] FIG. 22 is a schematic view of a mandrel connector according to some embodiments of the present disclosure;

[0094] FIG. 23a is a schematic perspective view of a sleeve joint and a positioning cylinder according to some embodiments of the present disclosure;

[0095] FIG. 23b is a schematic view of a sectional structure of a sleeve joint and a positioning cylinder according to some embodiments of the present disclosure;

[0096] FIG. 24a is a schematic perspective view of a polish rod joint and a positioning rod according to some embodiments of the present disclosure;

[0097] FIG. 24b is a schematic view of sectional structures of a polish rod joint and a positioning rod according to some embodiments of the present disclosure;

[0098] FIG. 25 is a schematic structural view of a positioning cylinder according to some embodiments of the present disclosure;

[0099] FIG. 26 is a schematic structural view of a positioning rod according to some embodiments of the present disclosure;

[0100] FIG. 27a is a schematic view of an end surface of a fairing cap according to some embodiments of the present disclosure;

[0101] FIG. 27b is a schematic view of a sectional structure of a fairing cap according to some embodiments of the present disclosure;

[0102] FIG. 28 is a schematic view of a pressure pulse signal according to one of some embodiments of the present disclosure;

[0103] FIG. 29 is a schematic structural view of a coded hole according to some embodiments of the present disclosure.

[0104] In the figures: 10. outer cylinder;

[0105] 1. pulse generator; 11. coded disk; 111. coded hole; 112. first boss; 113. first mounting tooth; 12. valve block; 121. cylindrical connection; 122. fan-shaped blocking portion; 123. pin connection; 13. key sleeve; 131. second mounting tooth; 14. retaining ring; 15. wear-resistant column; 16. wear-resistant groove; 17. gravity valve stem; 171. first flat key; 172. connection slot; 173. first keyway; 18. valve stem joint; 181. first square hole; 182. first stepped hole; 1821. first large diameter portion; 1822. first small diameter portion; 1823. second keyway; 183. first threaded hole; 19. spring; 101. first housing; 1011. mounting groove; 2. gravity-oriented sensor; 21. rotary shaft; 211. first through hole; 22. eccentric weight block; 221. clamping groove; 222. first semi-cylinder; 223. second semi-cylinder; 23. clamping block; 231. first screw; 24. cover plate; 241. second screw; 243. first mounting hole; 244. third mounting hole; 245. second large diameter portion; 246. second small diameter portion; 25. second boss; 26. second flat key; 27. bearing seat assembly; 2701. first bearing seat; 2702. second bearing seat; 2703. first bearing mounting portion; 2704. first sealing ring; 2705. second bearing mounting portion; 2706. second sealing ring; 271. first flow hole; 272. thrust bearing; 273. bearing retaining ring; 274. radial bearing; 28. fixing ring; 281. second flow hole; 29. protective shell; 291. second mounting hole; 292. mounting pin; 293. annular blind end; 102. second housing;

[0106] 3. mandrel connector; 31. sleeve joint; 311. first meshing tooth; 312. first square hole; 313. first round hole; 32. polish rod joint; 321. second meshing tooth; 33. positioning cylinder; 331. open slot; 332. first connection block; 34. positioning rod; 341. second connection block; 35. ring gear;

[0107] 4. upper connector;

[0108] 5. fairing cap;

[0109] 6. drill bit; 61. centralizer;

[0110] 71. sealing plate; 711. third sealing ring;

[0111] 72. sealing cover;

[0112] 100. drilling tool face measuring apparatus;

[0113] 200. mandrel assembly; 200′. mandrel assembly.

[0114] In the present application, all the accompanying drawings which are schematic accompanying drawings, are only used to illustrate the principles of the present invention, and are not drawn to actual scale.DETAILED DESCRIPTION

[0115] The present disclosure will be introduced below by way of the accompanying drawings.

[0116] It is to be noted that, in the present application, the direction proximate to the wellhead of the present disclosure after running in hole is described as “up”, “top” or similar terms, that is, the right side of FIG. 1, while the direction away from the wellhead is described as “down”, “bottom” or similar terms, that is, the left side of FIG. 1. They are not used to limit the absolute positions of the parts involved, but may vary according to specific conditions.

[0117] FIG. 1 shows the structure of a drilling tool face measuring apparatus 100 according to the embodiment of the present disclosure. As shown in FIG. 1, in order to enable the diagram to clearly present an overall structure of the drilling tool face measuring apparatus 100, the drilling tool face measuring apparatus 100 in FIG. 1 is divided into an upper portion and a lower portion, and the connection relationship between the upper portion and the lower portion is shown by the center line arrow in FIG. 1. The left side of the lower half in FIG. 1 is away from the wellhead for connection with the drill bit, and the right side of the upper half in FIG. 1 is proximate to the wellhead.

[0118] FIG. 2 is a schematic view of a pulse generator according to some embodiments of the present disclosure. Referring to FIGS. 1 and 2, in one aspect of the embodiment of the present disclosure, a drilling tool face measuring apparatus 100 is provided. The drilling tool face measuring apparatus 100 which is connected above the drill bit, includes an outer cylinder 10, a coded disk 11, a valve block 12 and a gravity-oriented sensor 2. The outer cylinder 10 rotates synchronously with the drill bit, the coded disk 11 is coaxially and fixedly arranged inside the outer cylinder 10, and a plurality of coded holes 111 with different sizes are uniformly arranged on the coded disk 11 along a circumferential direction. The valve block 12 is coaxially and rotatably connected with the coded disk 11, and the valve block 12 is configured to at least partially block at least one coded hole 111 during the rotation, but keeps at least another coded hole 111 clear. The center of gravity of the gravity-oriented sensor 2 does not coincide with the axis of rotation of the valve block 12, so that the valve block 12 always faces towards one direction under the action of gravity.

[0119] In some embodiments according to the present disclosure, the drilling tool face measuring apparatus 100 includes a pulse generator 1 and a gravity-oriented sensor 2, which are connected in series with each other. In this embodiment, the pulse generator 1 is coaxially arranged above the drill bit (not shown in FIG. 1), and the gravity-oriented sensor 2 is coaxially arranged above the pulse generator 1. The gravity-oriented sensor 2 and the pulse generator 1 cooperate with each other to generate a pulse signal during the rotation process of the drill bit.

[0120] Specifically, as shown in FIG. 2, in some embodiments, the pulse generator 1 includes a first housing 101, a coded disk 11, and a valve block 12. The coded disk is coaxially and fixedly arranged inside the first housing 101, and the coded disk 11 is uniformly provided with a plurality of coded holes 111 with different sizes to penetrate along a circumferential direction, that is, the coded disk 11 has a plurality of coded holes 111 axially penetrating through the coded disk 11 and distributed along a circumferential direction, and the valve block 12 is coaxially and rotatably connected with the coded disk 11, and the valve block 12 is configured to at least partially block at least one coded hole 111 during the rotation, but at least another coded hole 111 is clear. That is, the valve block 12 can rotate coaxially relative to the coded disk 11, and open and close different coded holes 111 among the plurality of coded holes 111 at various rotational positions relative to the coded disk 11.

[0121] As shown in FIG. 2, in some embodiments, the first housing 101 is in a cylindrical shape, and it is easily understood that the first housing 101 is a part of the outer cylinder 10 of the drilling tool face measuring apparatus 100. The upper and lower ends of the first housing 101 are provided with internal threads and external threads respectively, so that the lower end of the first housing 101 is connected with a centralizer 61 through external threads, and a drill bit 6 is fixedly arranged at the lower end of the centralizer 61. The specific structures of the drill bit 6 and the centralizer 61 are the prior art, which will not be described in detail here. In this connection method, the first housing 101 of the pulse generator 1 can rotate together with the drill bit 6 during the operation process.

[0122] Referring to FIGS. 1 and 2, in some embodiments, a coded disk 11 is coaxially and fixedly arranged inside the first housing 101, and a plurality of coded holes 111 with different sizes are uniformly distributed on the coded disk 11 along a circumferential direction, the plurality of coded holes 111 penetrate through the coded disk 11, that is, a plurality of coded holes 111 are arranged at equal angular intervals on the coded disk 11 along a circumferential direction, and the cross-sectional dimensions of the coded holes are different. The coded disk 11 is coaxially and rotatably provided with a valve block 12 capable of at least partially blocking the coded holes 111 and keeping at least one coded hole 111 in a clear state during the process of rotating relative to the coded disk 11. By way of this arrangement, during the process that the drilling fluid bypasses the coded disk 11, the valve block 12 rotates relative to the coded disk 11 to change a diameter dimension of the coded disk 11 so that the drilling fluid generates different pulse signals.

[0123] In order to enable the valve block 12 to rotate relative to the coded disk 11, in some embodiments, the valve block 12 is fixedly connected with the gravity-oriented sensor 2, that is, the gravity-oriented sensor 2 is rotatably arranged in the outer cylinder 10 and connected with the valve block 12. The center of gravity of the gravity-oriented sensor 2 is provided to be non-coincident with the axis of rotation of the valve block 12. Thus, under the action of gravity, the center of gravity of the gravity-oriented sensor 2 always faces towards the lower side of the wellbore inclination, that is, the gravity-oriented sensor 2 can drive the valve block 12 to rotate synchronously about the axis of rotation of the valve block 12, so that the gravity-oriented sensor 2 can drive the valve block 12 to rotate synchronously about the axis of rotation of the valve block 12, so as to cause the valve block 12 to maintain the orientation relative to the axis of rotation of the valve block 12 under the action of gravity. Under this arrangement, during the process of rotating the coded disk 11 along with the drill bit, the coded holes 111 with different sizes can cooperate with the flowing drilling fluid to generate a pulse fluctuation under the alternate blocking of the valve block 12. According to the present disclosure, when the pulse fluctuation changes, the coded hole 111 corresponding to the pulse waveform that causes a waveform change just rotates to the lower side of the wellbore inclination, so that the current tool face angle can be obtained by analyzing the pulse wave. In addition, the pulse generator 1 of the present disclosure can also produce the effect of reducing the friction and lessening the resistance during the drilling process.

[0124] In some related arts, the coded disk 11 is fixed in the outer cylinder 10 by screws, and the drill bit 6 can generate great vibration during the working process, so that it is likely that the coded disk 11 proximate to the drill bit 6 is not stable, and the local connection method of screw connection is prone to cause stress concentration, which increases the risk that the coded disk 11 is deformed or loosened, so as to affect the reliability of the detection result.

[0125] In some embodiments of the present disclosure, the inner wall of the outer cylinder 10 includes a plurality of mounting grooves arranged along a circumferential direction and extending along an axial direction, the coded disk 11 is provided with a plurality of mounting teeth into one-to-one correspondence with the plurality of mounting grooves, and the coded disk 11 is fixed inside the outer cylinder 10 by embedding the plurality of mounting teeth into the plurality of mounting grooves. One end of the coded disk 11 can abut against the end of the mounting groove 1011 through the mounting teeth 113. In this way, the coded disk 11 can be stably mounted in the outer cylinder 10, so that the coded disk 11 can still maintain its mounting position relative to the outer cylinder 10 in the case of great vibration.

[0126] In some embodiments of the present disclosure, as shown in FIGS. 2 and 5, three mounting grooves 1011 axially arranged are uniformly distributed on the inner wall of the first housing 101 along a circumferential direction. The lower end of the mounting groove 1011 (one end proximate to the drill bit 6) is enclosed and the upper end is clear.

[0127] As shown in FIGS. 2, 3a, 3b and 3c, in some embodiments, the coded disk 11 is integrally cylindrical, and the outer diameter of the cylinder matches the inner diameter of the first housing 101. Three first mounting teeth 113 are uniformly distributed on the edge of the coded disk 11 along a circumferential direction. The cross-sectional shape of the first mounting tooth 113 matches that of the mounting groove 1011. The coded disk 11 can be slidably fitted with the mounting groove 1011 of the first housing 101 through the first mounting teeth 113, so as to be mounted into the first housing 101 from top to bottom along an axial direction.

[0128] A key sleeve 13 and a retaining ring 14 are coaxially arranged inside the first housing 101. As shown in FIG. 6, in some embodiments, the key sleeve 13 integrally presents a cylindrical shape, and the outer diameter of the cylindrical shape matches the inner diameter of the first housing 101. The outer wall of the key sleeve 13 is provided with a plurality of mounting teeth into one-to-one correspondence with the plurality of mounting grooves. Referring to FIG. 6, three second mounting teeth 131 are uniformly arranged on the outer cylindrical surface of the key sleeve 13 along a circumferential direction, and the cross-sectional shape of the second mounting teeth 131 matches that of the mounting groove 1011. As described above, the coded disk 11 is mounted into the first housing 101 from top to bottom along an axial direction until the first mounting teeth 113 of the coded disk 11 abut against the lower end face of the mounting groove 1011, and at this time the coded disk 11 is mounted in place. Then, the key sleeve 13 is mounted into the first housing 101 from top to bottom along an axial direction until the lower end face of the key sleeve 13 abuts against the upper end face of the coded disk 11, and at this time the key sleeve 13 is mounted in place. Finally, the retaining ring 14 is mounted on the upper portion of the key sleeve 13. As shown in FIG. 2, the contact ends of the retaining ring 14 and the key sleeve 13 are provided to be two-stage cylindrical steps matched with each other.

[0129] It is easy to understand that although three mounting grooves 1011, three first mounting teeth 113 and three second mounting teeth 131 are provided in the illustrated embodiments, the numbers of the mounting grooves 1011, the first mounting teeth 113 and the second mounting teeth 131 can be appropriately selected by those skilled in the art as needed in actual conditions. These changes are all within the scope of the present disclosure.

[0130] In some embodiments, the internal threads at the upper end of the first housing 101 are provided to be a conical shape that expands upward. By way of this arrangement, on the one hand, it is convenient to mount the coded disk 11, the key sleeve 13 and the retaining ring 14. On the other hand, after threaded connection with the first housing 101, the upper downhole tool can axially abut against the retaining ring 14, so that the coded disk 11 is axially fixed by the key sleeve 13.

[0131] According to the present disclosure, as shown in FIGS. 2, 3a, 3b and 3c, in some embodiments, in order to facilitate machining a contact surface for mating with the valve block 12, a first boss 112 protruding outward is coaxially arranged at one end of the coded disk 11 for contacting with the valve block 12, and a plurality of coded holes 111 are uniformly arranged at the position of the first boss 112 along a circumferential direction. A wear-resistant column 15 is coaxially arranged on one side of the coded disk 11 proximate to the valve block 12, for coaxially and rotatably cooperating with the valve block 12. Specifically, the wear-resistant column 15 in this embodiment is a PDC composite sheet, which is embedded in the first boss 112 of the coded disk 11 to cooperate with the valve block 12, so as to lessen the wear and reduce the friction coefficient during the relative rotation process, so that both of them cooperate more smoothly. The wear-resistant column 15 is not limited to the PDC composite sheet in this embodiment, and other wear-resistant and lubricating materials can also be used.

[0132] The coded disk 11 and the valve block 12 are continuously worn during use, and the PDC composite sheet embedded between the coded disk 11 and the valve block 12 can also be worn off, so that the coded disk 11, the valve block 12 and the PDC composite sheet are present with a need for replacement or maintenance. Therefore, the embedded mounting structure of the coded disk 11 realized by the retaining ring 14 and the key sleeve 13 can make it more convenient to install and remove the coded disk 11, the valve block 12 and the PDC composite sheet. Moreover, the positioning function of the coded disk 11 by the retaining ring 14 and the key sleeve 13 along an axial direction is combined with the positioning function of the mounting teeth of the coded disk 11 and the mounting groove 1011 on the inner wall of the first housing 101 along circumferential and radial directions, so that the coded disk 11 and the first housing 101 are more stably and reliably fixed along circumferential, axial and radial directions, which is beneficial for the drilling tool face measuring apparatus to obtaining a more accurate detection result. As shown in FIGS. 4a, 4b and 4c, in some embodiments, the valve block 12 includes a cylindrical connection 121 in a cylindrical shape and a fan-shaped blocking portion 122 in a fan shape. The center of circle of the cylindrical connection 121 coincides with that of the fan-shaped blocking portion. Among them, a wear-resistant groove 16 for rotary fit with the wear-resistant column 15 is provided at a central axis of the cylindrical connection 121. By way of this arrangement, the valve block 12 can be plugged with the wear-resistant column 15 through the wear-resistant groove 16 to form a rotary pair. Meanwhile, after the valve block 12 is connected with the wear-resistant column 15 through the wear-resistant groove 16, the end face of the valve block 12 is in frictional contact with the first boss 112 of the coded disk 11. Specifically, the radius of the fan-shaped blocking portion 122 of the valve block 12 is equal to that of the first boss 112. The machining accuracy of the contact surface between the fan-shaped blocking portion 122 and the first boss 112 is controlled so that both of them rotate relatively while the fan-shaped blocking portion 122 can block the coded hole 111.

[0133] In this embodiment, the fan-shaped blocking portion 122 at most blocks one coded hole 111 at the same time. Specifically, in the case where n coded holes 111 are provided, the included angle between adjacent coded holes 111 is 360 / n degrees, and the fan-shaped angle of each coded hole 111 is N=360° / (2n). The angle of the fan-shaped blocking portion 122 is equal to the fan-shaped angle N of the coded hole 111.

[0134] In some embodiments, the number of the coded holes 111 is set to six, the included angle between two adjacent coded holes 111 is 60 degrees, and the fan-shaped angle N of each coded hole 111 is 30 degrees. The adjacent angle of the first mounting teeth 113 is 120 degrees, that is, 4N degrees. In order to set each coded hole 111 to be in different sizes when each coded hole 111 has the same fan-shaped angle N, the present disclosure provides three different embodiments as shown in FIGS. 3a, 3b and 3c. In the embodiments shown in FIGS. 3a and 3b, the coded holes 111 are elliptical in different sizes, and in the embodiment shown in FIG. 3c, the coded holes 111 are circular in different sizes, wherein under the same fan-shaped angle, the closer the coded holes 111 are to the center of circle of the coded disk 11, the smaller the size thereof will be. Therefore, the distance between these coded holes 111 and the center of circle of the coded disk 11 is adjusted so that the fan-shaped angles of the coded holes 111 with different sizes occupying the coded disk 11 are equal.

[0135] It is easy to understand that although six coded holes 111 are provided in the illustrated embodiments, the fan-shaped angle of the valve block 12 is equal to that of one coded hole 111, and the number of the coded holes 111 and the fan-shaped angle of the valve block 12 can be appropriately selected by those skilled in the art as needed in actual conditions. These changes are all within the scope of the present disclosure.

[0136] In this embodiment, the coded holes 111 are encoded according to the law of 1, 2 and 3 in an ascending sequence, so that the coded holes 111 on the whole coded disk 11 are coded as “3, 2, 1, 3, 1, 2”, and fed back to the signal receiving software, and the received pressure fluctuation curve is shown in FIG. 28.

[0137] According to the present disclosure, in some embodiments, the pulse generator 1 further includes a gravity valve stem 17 and a valve stem joint 18. As shown in FIGS. 4b and 4c, in some embodiments, a pin connection 123 is coaxially and fixedly arranged on one side of the cylindrical connection 121 of the valve block 12 away from the coded disk 11. Meanwhile, as shown in FIG. 7, in some embodiments, the lower end of the gravity valve stem 17 is provided with a connection slot 172 for fixed connection with the pin connection 123. Among them, FIGS. 4b and 4c show two different embodiments of the pin connection 123. In the embodiment shown in FIG. 4b, the pin connection 123 is cylindrical. In this embodiment, the pin connection 123 is fixedly connected with the gravity valve stem 17 by way of interference connection. In the embodiment shown in FIG. 4c, the pin connection 123 has a conical shape. In this embodiment, the pin connection part 123 is fixedly connected with the gravity valve stem 17 by way of pin connection. The upper end of the gravity valve stem 17 is provided with a first keyway 173.

[0138] As shown in FIG. 8, in some embodiments, the lower end of the valve stem joint 18 is provided with a first stepped hole 182, and the first stepped hole 182 is provided as a secondary stepped hole. The first large diameter portion 1821 of the first stepped hole 182 is located outside the first small diameter portion 1822, and the first large diameter portion 1821 of the first stepped hole 182 is provided with a second keyway 1823. As shown inFIG. 2, the first large diameter portion 1821 of the first stepped hole 182 is connected with the upper end of the gravity valve stem 17 through the first flat key 171, and the first flat key 171 is mounted in the first keyway 173 and the second keyway 1823, so that both of them can move axially relative to each other within a certain range while torque is transferred. The first small diameter portion 1822 of the first stepped hole 182 is internally provided with a spring 19, both ends of which abut against the gravity valve stem 17 and the valve stem joint 18 respectively.

[0139] In other words, the valve stem joint 18 is provided with a stepped hole, the stepped hole is located at one end of the valve stem joint 18 but not limited to be adjacent to the gravity valve stem 17. The stepped hole has a first hole section and a second hole section, wherein the second hole section is located inside the first hole section, and the cross-sectional dimension of the first hole section is larger than that of the second hole section. The first hole section is connected with the gravity valve stem 17 through a flat key, and the large diameter portion of the stepped hole is located on the outer side, and connected with the gravity valve stem 17 by way of plugging. The elastic member includes a spring 19 which is arranged in the second hole section and both ends of which abut against the gravity valve stem 17 and the valve stem joint 18 respectively, that is, the spring 19 is arranged in the small diameter portion of the stepped hole, and both ends of the spring 19 abut against the gravity valve stem 17 and the valve stem joint 18 respectively. Compared with the related art that the spring is sleeved on the shaft, a stepped hole is provided so that it is possible to prevent the valve stem from circumferential rotation and axial movement. Since the spring is not required to be sleeved on the mandrel, and the mandrel is not required to be set in an excessively long length, so that it is possible to reduce the processing and assembling requirements for the spring and the mandrel.

[0140] A first square hole 181 is arranged at the position of the central axis at the upper end of the valve stem joint 18, and a square rotary shaft 21 is arranged at a corresponding end of the first square hole 181, so that both of them are plugged with each other to transfer torque. The first square hole 181 can be axially plugged with the gravity-oriented sensor 2 to transfer torque. The upper end of the valve stem joint 18 is radially provided with a first threaded hole 183 intersecting with the first square hole 181. A through hole through which a screw can pass can be arranged at the square portion of the rotary shaft 21 and the position of the valve stem joint 18 corresponding to the first square hole 181 to penetrate along a radial direction. After the square portion of the rotary shaft 21 is plugged into the first square hole 181, a screw can also be provided to penetrate along a radial direction so that a bolt (not shown) is provided to penetrate through the first threaded hole 183 and the bolt passes through a connection member of the gravity-oriented sensor 2, which enables a more solid connection therebetween.

[0141] By providing the gravity valve stem 17 and the valve stem joint 18, the valve block 12 is connected with the gravity-oriented sensor 2, and at the same time, the spring 19 is arranged between the gravity valve stem 17 and the valve stem joint 18 so as to generate a certain downward thrust on the valve block 12, so that the valve block 12 is preloaded so as to be in close contact with the first boss 112 of the coded disk 11. That is, the valve block 12 and the gravity-oriented sensor 2 are connected through the gravity valve stem 17 and the valve stem joint 18, and the gravity valve stem 17 is movable relative to the valve stem joint 18 along an axial direction, and the spring 19 is not limited to being arranged coaxially between the gravity valve stem 17 and the valve stem joint 18.

[0142] As shown in FIGS. 9 and 16, in some embodiments, the gravity-oriented sensor 2 is provided with a mandrel assembly 200, which includes a rotary shaft 21 and an eccentric weight block 22 fixedly arranged on the rotary shaft 21, wherein the eccentric weight block causes the center of gravity of the mandrel assembly 200 to deviate from the axis of rotation of the rotary shaft 21. The gravity-oriented sensor 2 includes a second housing 102 in the shape of a hollow sleeve, and the mandrel assembly 200 is rotatably arranged inside the second housing 102 through the bearing seat assembly 27 arranged at both ends. In addition to this purpose as a drilling measuring tool in this embodiment, the mandrel assembly 200 in this embodiment can also serve as a stable platform that needs to stabilize the center of gravity, such as a rotary navigator drilling studio and a vertical drilling tool.

[0143] As shown in FIGS. 9 and 16, in some embodiments, the gravity-oriented sensor 2 is provided with a mandrel assembly 200′, which includes a rotary shaft 21, a protective shell 29 and an eccentric weight block 22, wherein the protective shell 29 is coaxially sleeved on the rotary shaft 21, and the eccentric weight block 22 is fixedly arranged on the rotary shaft 21. The eccentric weight block 22 is arranged between the rotary shaft 21 and the protective shell 29, and the eccentric weight block 22 causes the center of gravity of the mandrel assembly 200 to deviate from the axis of rotation of the rotary shaft 21. The gravity-oriented sensor 2 includes a second housing 102 in the shape of a hollow sleeve, and the mandrel assembly 200 is rotatably arranged in the second housing 102 through the bearing seat assembly 27 arranged at both ends. The mandrel assembly 200 in this embodiment uses a purely mechanical structure to achieve the effect of stabilizing the unbalance. In addition to this purpose as a drilling measuring tool in this embodiment, the mandrel assembly 200 in this embodiment can also serve as a stable platform that needs to stabilize the center of gravity, such as a rotary navigator drilling studio and a vertical drilling tool.

[0144] According to the present disclosure, the structure of the gravity-oriented sensor 2 is shown in FIG. 9. In some embodiments, the gravity-oriented sensor 2 mainly includes a rotary shaft 21 coaxially and rotatably arranged in the outer cylinder 10 and an eccentric weight block 22 fixedly arranged on the rotary shaft 21. Specifically, as shown in FIG. 12a and FIG. 12b, the eccentric weight block 22 includes two semi-cylinders with the same volume enclosing the rotary shaft 21, one of which is formed of a first material, and the other of which is formed of a second material, wherein the density of the second material is greater than that of the first material. That is, the eccentric weight block 22 includes first and second semi-cylinders 222 and 223 with the same volume and the first and second semi-cylinders 222 and 223 enclose the rotary shaft 21 to form a fixed connection structure. One of the eccentric weight blocks 22 is formed of a material with low density and small mass, for example, plastic and light alloy. The other eccentric weight block 22 is formed of a material with high density and large mass, for example, high-density alloy or lead block. In this embodiment, the two eccentric weight blocks 22 have the same volume, but are formed of different densities of materials respectively, so that the center of gravity of the whole formed by the two eccentric weight blocks 22 is not at its centroid position. In other words, after the eccentric weight block 22 is fixedly connected with the rotary shaft 21, the center of gravity of the whole can deviate from the axis of rotation of the rotary shaft 21, so that the gravity-oriented portion of this whole is directed to the lower side of the wellbore inclination under the action of gravity.

[0145] In some embodiments, the outer wall of the rotary shaft 21 is provided with a clamping block 23 axially arranged and protruding outwards, such that the clamping block 23 is fixedly connected with the rotary shaft by way of bolt connection, including but not limited to fixedly connected with the rotary shaft 21 through the first screw 231. In addition, an integral arrangement method can also be used so that the clamping block 23 and the rotary shaft 21 are provided to be an integral structure, which facilitates machining using a casting method. That is, the clamping block 23 is fixedly connected with the rotary shaft 21 by way of bolt connection or integral formation.

[0146] The inner wall of the eccentric weight block 22 is provided with a clamping groove 221 for clamping with the clamping block 23. When two eccentric weight blocks 22 enclose the rotary shaft 21, the clamping groove 221 of the eccentric weight block 22 is clamped with the clamping block 23, so that the eccentric weight blocks 22 cannot move relative to the rotary shaft 21 along a circumferential direction or an axial direction.

[0147] The present disclosure provides two structures for the clamping block 23. As shown in FIG. 10, in some embodiments, the clamping block 23 is arranged with multi-segment configuration. In this embodiment, the clamping block 23 is in three sections, including but not limited to three sections with the same length, which are uniformly arranged on the outer wall of the rotary shaft 21 along an axial direction, that is, arranged at intervals along an axial direction. As shown in FIG. 11, the clamping block 23 can also be arranged in a whole section of a strip shape, arranged on the outer wall of the rotary shaft 21 along an axial direction, that is, the clamping block is arranged in a strip shape along a generatrix extension direction of the rotary shaft 21. In these two arrangements, the outer wall of the rotary shaft 21 is provided with a countersunk groove in a recessed shape which matches the clamping block 23, so that the clamping block 23 is limitedly mounted on the rotary shaft 21 and fixed by the first screw 231. Specifically, the first screw 231 is a countersunk head screw, so as to avoid the influence of the first screw 231 on the installation of the eccentric weight block 22. It is easy to understand that, in this embodiment, two eccentric weight blocks 22 are provided, each of which corresponds to one clamping block 23.

[0148] In some embodiments, in order to avoid stress concentration, the clamping block 23 can also be provided in a cylindrical shape (not shown in the figure). Correspondingly, the recessed countersunk groove on the rotary shaft 21 for mounting the clamping block 23 is provided in an arc shape conforming to the shape of the clamping block 23. At the same time, the clamping groove 221 on the inner side of the eccentric weight block 22 is also provided in an arc shape conforming to the shape of the clamping block 23.

[0149] According to the present disclosure, a cover plate 24 is provided at both ends of the eccentric weight block 22, so that the outer end of the cover plate 24 extends axially towards the direction of the eccentric weight block 22. As shown in FIGS. 9 and 10, in some embodiments, a second boss 25 is coaxially arranged at a corresponding position of the rotary shaft 21 where the cover plate 24 is mounted, that is, the second boss 25 is arranged at both ends of the rotary shaft 21 corresponding to the eccentric weight block 22. The second boss 25 can axially position the eccentric weight block 22 on the one hand, and provides an installation basis for the installation of the cover plate 24 on the other hand.

[0150] Specifically, the cover plate 24 is annular and coaxially sleeved on the second boss 25 by way of clearance fit. Meanwhile, the cover plate 24 and the second boss 25 are connected by the second flat key 26, and the cover plate 24 and the eccentric weight block 22 are fixedly connected by screws that are axially arranged (not shown in the figure). The keyway for mounting the second flat key 26 is arranged on one side of the cover plate 24 and the second boss 25 proximate to the eccentric weight block 22. After the cover plate 24 is mounted on the second boss 25 through the second flat key 26, one axial end of the second flat key 26 abuts against the cover plate 24 and the second boss 25, and the other end abuts against the eccentric weight block 22, thereby preventing the second flat key 26 from disengagement from the keyway. As shown in FIG. 10, the keyway for mounting the second flat key 26 and the clamping block 23 are located in the same generatrix direction of the rotary shaft 21. In the related art, it is necessary that the eccentric weight block, the boss and the cover plate cooperate with each other to realize the fixation without disengagement, which has high requirements for the matching accuracy of the eccentric weight block, the boss and the cover plate. In some embodiments, the second boss 25 prevents axial motion of the eccentric weight block 22, and the cover plate 24 is fixedly connected with the eccentric weight block 22 so that both of them cooperate with each other without disengagement, which can reduce the machining and assembling accuracy.

[0151] In some embodiments, the axial thickness of the cover plate 24 is less than that of the second boss 25. Specifically, the cover plate 24 is connected with the second boss 25 through the second flat key 26, and after the cover plate 24 is fixedly connected with the eccentric weight block 22 by screws that are axially arranged, one axial end of the cover plate 24 is flush with one end of the second boss 25 and abuts against the eccentric weight block 22. Since the axial thickness of the cover plate 24 is less than that of the second boss 25, the other axial end of the cover plate 24 is within the axial thickness of the second boss 25. Under this arrangement, when the gravity-oriented sensor 2 is connected with other parts, it is possible to avoid that the cover plate 24 is in contact with and pressed against other parts to generate friction, which has an influence on the unbalance effect. In one specific embodiment, the distance from one side of the cover plate 24 away from the eccentric weight block 22 to one side of the second boss 25 away from the eccentric weight block 22 is 0.5-3 mm.

[0152] As shown in FIG. 9, in some embodiments, the edge of the cover plate 24 extends to one side of the eccentric weight block 22, and at the same time, a step that is fit with an extension edge of the cover plate 24 is arranged at the end edge of the eccentric weight block 22. With this arrangement, the cover plate 24 can radially limit the eccentric weight block 22. As shown in FIGS. 13, 14a and 14b, after the edge of the cover plate 24 extends to one side of the eccentric weight block 22, the cover plate 24 includes a second large diameter portion 245 and a second small diameter portion 246, wherein the portion where the cover plate 24 cooperates with the second boss 25 is the second small diameter portion 246, and the portion where the cover plate 24 radially abuts against the eccentric weight block 22 is the second large diameter portion 245. Six first mounting holes 243 that are radially arranged are distributed on the plate wall of the cover plate 24 corresponding to the second small diameter portion 246 along a circumferential direction, and the included angle between two adjacent first mounting holes 243 is 60 degrees. The first mounting hole 243 is a countersunk hole, and the first mounting hole 243 is internally provided with a second screw 241, through which the cover plate 24 is fixedly connected with the eccentric weight block 22.

[0153] As shown in FIG. 14a, in some embodiments, three third mounting holes 244 are uniformly arranged on the plate wall corresponding to the small diameter portion of the cover plate 24 along a circumferential direction, and the included angle between two adjacent third mounting holes 244 is 120 degrees, and the included angle between the third mounting hole 244 and the first mounting hole 243 that is closest thereto is 30 degrees. In the case where a multi-section unbalance apparatus is used, three third mounting holes 244 are used for connection with a gravity-oriented apparatus of other sections. For the specific connection structure, please see the following description.

[0154] It is easy to understand that, although six first mounting holes 243 and three third mounting holes 244 are provided in the illustrated embodiments, the numbers of the first mounting holes 243 and the third mounting holes 244 can also be appropriately selected by those skilled in the art as needed in actual conditions. These changes are all within the scope of the present disclosure.

[0155] The outer side at the boundary position of the second large diameter portion 245 and the second small diameter portion 246 of the cover plate 24 is rounded, so as to reduce the fluid resistance and facilitate the drilling fluid to flow through the gravity-oriented sensor 2.

[0156] In some embodiments, a protective shell 29 is also sleeved on the outer side of the eccentric weight block 22, as shown in FIG. 9. The protective shell 29 is a cylindrical thin shell structure, and both ends of the protective shell 29 axially abut against the edge portions of the two cover plates 24 extending to one side of the eccentric weight block 22. The protective shell 29 avoids that the eccentric weight block 22 is scoured and worn by hard particles in the borehole wall or the circulated drilling fluid during the underground operation, thereby prolonging the service life.

[0157] Referring to FIG. 9, in some embodiments, an annular space is present between the protective shell 29 and the second housing 102, which enables circulation of the drilling fluid. The outer side of the boundary position of the second large diameter portion 245 and the second small diameter portion 246 of the cover plate 24 is rounded, so as to reduce the fluid resistance and facilitate the drilling fluid to flow through the gravity-oriented sensor 2.

[0158] As shown in FIGS. 15a and 15b, in some embodiments, the protective shell 29 has two semi-cylindrical structures with annular blind ends 293. Among them, the annular blind end 293 is uniformly provided with three axial second mounting holes 291 for cooperating with the mounting pin 292, that is, the included angle between two adjacent second mounting holes 291 is 60 degrees. As shown in FIG. 13, the mounting pin 292 can penetrate through the second mounting hole 291 and enter the eccentric weight block 22. The plate wall of the large diameter portion of the cover plate 24 axially abuts against the annular blind end 293 to prevent the mounting pin 292 from disengagement.

[0159] According to the present disclosure, the distances from the two second bosses 25 to the end of the rotary shaft 21 are denoted as L1 and L2 in FIG. 9 respectively. In this embodiment, the length of L1 is greater than the length of L2. It is easy to understand that, the lengths of L1 and L2 can be set according to actual needs. Further, the lengths of L1 and L2 can be set according to the downhole tools connected at both ends of the rotary shaft 21.

[0160] Referring to FIGS. 1, 9 and 10, in some embodiments, the upper and lower ends of the rotary shaft 21 are provided to be square, and the gravity-oriented sensor 2 is connected with the pulse generator 1 to jointly constitute a part of the drilling tool face measuring apparatus 100. During the working process, torque is required to be transferred between the gravity-oriented sensor 2 and the pulse generator 1. Therefore, the upper and lower ends of the rotary shaft 21 in this embodiment are provided to be a square that can transfer torque after both of them are connected.

[0161] In some embodiments, as shown in FIG. 10, the lower end of the rotary shaft 21 is provided to be a square, and the cross-sectional shape of the square matches the shape of the first square hole 181 at the upper end of the valve stem joint 18 of the pulse generator 1 of the present disclosure, so as to cooperate with the first threaded hole 183 to form the through hole through which the bolt passes. By way of this arrangement, the lower end of the rotary shaft 21 can be inserted into the upper end of the valve stem joint 18, so that both of them are connected with each other to transfer torque. During the working process, under the action of gravity of the gravity-oriented sensor 2, one gravity-oriented side of the two eccentric weight blocks 22 is always directed to the lower side of the wellbore inclination, and the rotary shaft 21 is fixed with the valve block 12 through the valve stem joint 18 and the gravity valve stem 17 in a circumferential direction. By way of this arrangement, when the coded disk 11 rotates along with the outer cylinder 10, the fixed connection of the valve block 12 with the gravity-oriented sensor 2 along a circumferential direction allows that the valve block 12 can rotate relative to the coded disk 11 in a circumferential direction, so that the valve block 12 sequentially cooperates with the coded holes 111 with different sizes to form regular pulses.

[0162] In some embodiments, the square end of the rotary shaft 21 is further provided with a first through hole 211 arranged along a radial direction. After the square end of the rotary shaft 21 is inserted into the first square hole 181 of the valve stem joint 18, the central axis of the first through hole 211 coincides with that of the first threaded hole 183 radially arranged on the valve stem joint 18, and the rotary shaft 21 and the valve stem joint 18 can be axially fixed by screwing therethrough.

[0163] According to the present disclosure, as shown in FIG. 16, in some embodiments, the gravity-oriented sensor 2 further includes a second housing 102, and the rotary shaft 21 is rotatably arranged in the second housing 102 by way of bearing connection. It is easy to understand that, the second housing 102 is a part of the outer cylinder 10 of the drilling tool face measuring apparatus 100. As shown in FIG. 1, when the pulse generator 1 is connected with the gravity-oriented sensor 2, the first housing 101 of the pulse generator 1 and the second housing 102 of the gravity-oriented sensor 2 are connected with each other by means of screw connection, so that the first housing 101 and the second housing 102 jointly constitute a part of the outer cylinder 10 of the drilling tool face measuring apparatus 100.

[0164] In some embodiments, a bearing seat assembly 27 is coaxially and fixedly arranged inside the second housing 102. Specifically, the bearing seat assembly 27 includes a first bearing seat 2701 and a second bearing seat 2702, for connection with the upper and lower ends of the rotary shaft 21 respectively.

[0165] FIGS. 17a and 17b show the structure of the first bearing seat 2701 arranged at the upper end of the rotary shaft 21. In some embodiments, the bearing seat assembly 27 is internally provided with a stepped hole for mounting the bearing, and one open end of the stepped hole faces towards the mandrel assembly 200. The bearing seat assembly 27 at the upper end of the mandrel assembly 200 is internally provided with a spherical roller bearing, and the bearing seat assembly 27 at the lower end of the mandrel assembly 200 is internally provided with a radial bearing and a thrust bearing. A stepped hole is arranged at the central axis of the first bearing seat 2701, the small diameter portion of the stepped hole is configured to be fittingly mounted the rotary shaft 21, and the large diameter portion of the stepped hole is the first bearing mounting portion 2703 for mounting a bearing. In this embodiment, a spherical roller bearing with the model number 22206 is mounted in the first bearing mounting portion 2703.

[0166] The mating surface of the sealing plate 71 and the bearing seat assembly 27 is provided with sealing rings that are coaxially rotatable and sealed with each other, that is, the mating surface of the sealing plate 71 and the bearing seat assembly 27 is provided with a sealing ring that is coaxially rotatable and sealed. A first sealing ring 2704 is coaxially fixed at the end face of the first bearing seat 2701 facing towards the cover plate 24, and the size of the first sealing ring 2704 is greater than that of the first bearing mounting portion 2703. A sealing plate 71 is coaxially fixed at the end face of the cover plate 24 facing towards the first bearing seat 2701, and the sealing plate 71 cooperates with the bearing seat assembly 27 to seal the stepped hole of the bearing seat assembly 27, so as to protect a bearing in the bearing seat assembly. As shown in FIGS. 20a and 20b, the sealing plate 71 is integrally annular, and three countersunk holes which are uniformly arranged at the edge position of the sealing plate 71 along a circumferential direction correspond to the three third mounting holes 244 of the cover plate 24 respectively, so that the sealing plate 71 and the cover plate 24 are fixedly and sealingly connected by means of bolt connection. The mating surface of the sealing plate 71 and the bearing seat assembly 27 is provided with sealing rings that are coaxially rotatable and sealed with each other, and the size of the sealing ring is greater than that of the stepped hole of the bearing seat assembly. A third sealing ring 711 is coaxially fixed on the end face of the sealing plate 71 facing towards the first bearing seat 2701, and the third sealing ring 711 and the first sealing ring 2704 of the first bearing seat 2701 are in dynamic sealing connection that they are sleeved with each other. By way of this arrangement, the bearing in the first bearing seat 2701 is sealed and protected to prevent fluid from entering the bearing.

[0167] At the same time, a plurality of first flow holes 271 are uniformly arranged to penetrate through the first bearing seat 2701 along a circumferential direction of the first bearing seat 2701, as a flow passage of the drilling fluid. The first flow holes 271 are located at the periphery of the first sealing ring 2704, that is, the size of a circle surrounded by a plurality of first flow holes 271 is larger than that of the first sealing ring 2704, thereby avoiding that the drilling fluid in the first flow holes 271 enters the first sealing ring 2704. In this embodiment, the first bearing seat 2701 is provided with three first flow holes 271, and the included angle between adjacent first flow holes 271 is 120 degrees. The first flow hole 271 is provided to be fan-shaped, and both ends of the first flow hole 271 along a circumferential direction are in a semicircular shape, and the included angle between the centers of semi-circles at both ends of the first flow hole 271 is N2 degrees.

[0168] FIGS. 19a and 19b show the structure of the second bearing seat 2702 arranged at the lower end of the rotary shaft 21. In some embodiments, the structure of the second bearing seat 2702 is similar to that of the first bearing seat 2701, except that the second bearing mounting portion 2705 of the second bearing seat 2702 is a stepped hole, the small diameter portion of which is used for mounting the radial bearing 274 with the model number NJ206E, and the large diameter portion of which is used for mounting the thrust bearing 272 with the model number 51406. Among them, the thrust bearing 272 is closer to the eccentric weight block 22 than the radial bearing 274.

[0169] Similar to the structure of the first bearing seat 2701, a second sealing ring 2706 is coaxially fixed at the end face of the second bearing seat2702 facing towards the cover plate 24, and the size of the second sealing ring 2706 is larger than that of the second bearing mounting portion 2705. Similarly, the cover plate 24 proximate to the second bearing seat 2702 is also fixedly sealed with a sealing plate 71, so that the third sealing ring 711 and the second sealing ring 2706 of the sealing plate 71 are in dynamic sealing connection that they are sleeved with each other, thereby sealing a bearing in the second bearing seat 2702.

[0170] As shown in FIG. 16, in some embodiments, a bearing retaining ring 273 is further provided between the thrust bearing 272 and the radial bearing 274.

[0171] According to the present disclosure, as shown in FIG. 16, in some embodiments, the inner wall at the lower end of the second housing 102 is provided with a step, and after the rotary shaft 21 is mounted on the second housing 102, the lower end of the second bearing seat 2702 abuts against the step on the inner wall of the second housing 102. The upper end of the second bearing seat 2702 abuts against the sealing plate 71 at the lower end of the rotary shaft 21. The sealing plate 71 at the upper end of the rotary shaft 21 abuts against the first bearing seat 2701. In order to fix the first bearing seat 2701 with the second housing 102, a fixing ring 28 is fixedly arranged at one end of the bearing seat assembly 27 away from the mandrel assembly 200, the fixing ring 28 is fixedly connected with the second housing 102. In this embodiment, the fixing ring 28 is fixedly arranged at the upper end of the first bearing seat 2701, and the cylindrical side surface of the fixing ring 28 is fixedly connected with the inner wall of the second housing 102.

[0172] The structure of the fixing ring 28 is shown in FIGS. 18a and 18b. In some embodiments, the fixing ring 28 is provided with a second flow hole 281 corresponding to the first flow hole 271 to extend radially through the fixing ring 28, and the size of the second flow hole 281 is larger than that of the first flow hole 271. Here, the sizes can be the cross-sectional dimensions of the second flow hole 281 and the first flow hole 271. In some embodiments, the second flow hole 281 is provided to be fan-shaped, and the fan-shaped angle of the second flow hole 281 is greater than that of the first flow hole 271. The fixing ring 28 is provided with a plurality of second flow holes 281 uniformly arranged along a circumferential direction, and each second flow hole 281 is in one-to-one correspondence with each first flow hole 271. The shape of the second flow hole 281 is similar to that of the first flow hole 271, but the difference is that the included angle between the centers of semicircles at both axial ends of the second flow hole 281 is N1 degrees, where N1>N2. For example, in this embodiment, the included angle between the centers of semicircles at both circumferential ends of the first flow hole 271 is 60 degrees, and the included angle between the centers of semicircles at both circumferential ends of the second flow hole 281 is 70 degrees. By setting the dimension relationship between the first flow hole 271 and the second flow hole 281, a gradual flow change can be formed along the fluid flow direction, so as to reduce the loss due to sudden flow change.

[0173] The fixing ring 28 is internally provided with a stepped hole. Under this arrangement, the edge position of the fixing ring 28 is thicker than the intermediate position, and the second flow hole 281 is arranged at a thin portion of the fixing ring 28. At the same time, the thin portion of the fixing ring 28 is used for mounting the fairing cap 5. For the specific structure of the fairing cap 5, please see the following. The planar end of the fixing ring 28 is in contact with the first bearing seat 2701, and the fixing ring 28 is fixed to the first bearing seat 2701 by four M4 screws that are uniformly arranged along a circumferential direction, so that the four screws are arranged at the inner side of the circle surrounded by the second flow hole 281.

[0174] In addition to producing the effect of fixing the first bearing seat 2701, the fixing ring 28 can also form a dynamic sealing connection relationship with the rotary shaft 21, thereby further strengthening the sealing protection of a bearing in the first bearing seat 2701. Since the lower end of the second bearing seat 2702 abuts against a step on the inner wall of the second housing 102, the second bearing seat 2702 is not required to be fixed like the first bearing seat 2701 using the fixing ring 28. In one specific embodiment, a sealing cover 72 is fixedly sealed at the end face of the second bearing seat 2702 away from the eccentric weight block 22. The structure of the sealing cover 72 is shown in FIGS. 21a and 21b, and the sealing cover 72 is integrally annular and sealingly and coaxially sleeved on the rotary shaft 21. Meanwhile, the sealing cover 72 is fixedly connected with the second bearing seat 2702 through four M4 screws uniformly arranged along a circumferential direction. As shown in FIG. 16, the diameter of the sealing cover 72 is less than that of a circle surrounded by a plurality of first flow holes 271. Therefore, after the sealing cover 72 is fixedly connected with the second bearing seat 2702, the sealing cover 72 can not block the first flow hole 271 of the second bearing seat 2702.

[0175] According to the present disclosure, a plurality of gravity-oriented sensors 2 can be used in series. During use in series, the connecting line of the centers of gravity of the plurality of gravity-oriented sensors 2 is parallel with the central axis of the rotary shaft 21, that is, the straight line of the mandrel connector 3 passing through the centers of gravity of the plurality of gravity-oriented sensors 2 is parallel with the axes of rotation of the plurality of gravity-oriented sensors 2, and heavier eccentric weight blocks 22 are all located at the same side, so that it is possible to superimpose the unbalance effect of the plurality of gravity-oriented sensors 2, thereby enhancing the gravity-oriented effect. The plurality of gravity-oriented sensors 2 can be connected through the mandrel connector 3.

[0176] FIG. 22 shows the structure of the mandrel connector 3 of the present disclosure. In some embodiments, the mandrel connector 3 serves as a part of the drilling tool face detection apparatus 100 for connection among the plurality of gravity-oriented sensors 2. The mandrel connector 3 includes a sleeve joint 31 and a polish rod joint 32 plugged with each other in a cylindrical shape, wherein a positioning cylinder 33 is fixedly arranged on the outer wall of the sleeve joint 31 along an axial direction, and a positioning rod 34 is fixedly arranged on the outer wall of the polish rod joint 32 along an axial direction. At the same time when the sleeve joint 31 is plugged with the polish rod joint 32, the positioning rod 34 and the positioning cylinder 33 are plugged with each other through the ring gear 35 arranged on the end faces thereof. The positioning rod 34 and the positioning cylinder 33 are plugged with each other in cooperation, for directional positioning. The sleeve joint 31 and the polish rod joint 32 are plugged with each other for transferring torque.

[0177] In some embodiments, as shown in FIGS. 23a and 23b, a plurality of first meshing teeth 311 are uniformly arranged at intervals at one end of the sleeve joint 31 along a circumferential direction, as a ring gear 35 of the sleeve joint 31. In this embodiment, there are three first meshing teeth 311, and the cross-sectional shape of a single first meshing tooth 311 is fan-shaped. The angle of the fan-shaped cross-section of the single first meshing tooth 311 is 60 degrees, and the gap angle between two adjacent first meshing teeth 311 is also 60 degrees.

[0178] A stepped hole is provided in the other end of the sleeve joint 31, the portion of the stepped hole proximate to the first meshing teeth 311 is a small diameter portion, which is a first square hole 312 provided to be a square that can be plugged with a square structure at the end of the rotary shaft 21, so as to transfer torque. The large diameter portion of the stepped hole inside the sleeve joint 31 is a first circular hole 313, which is provided to be a cylindrical shape that can be plugged with the cylindrical structure at the end of the rotary shaft 21. Among them, the first circular hole 313 is a circumscribed circle of the first square hole 312.

[0179] The positioning cylinder 33 has a cylindrical shape as a whole, and the cylinder wall of the positioning cylinder 33 is provided with an open slot 331 along a generatrix direction, that is, the cylinder wall of the positioning cylinder 33 is provided with an open slot 331 through which the second connection block 341 passes along a generatrix direction. The generatrix where the opening slot 331 is located, the central axis of the positioning cylinder 33 and the central axis of the sleeve joint 31 are in the same plane, and the opening slot 331 is used for the second connection block 341 to pass therethrough. The position where the positioning cylinder 33 is fixedly connected with the sleeve joint 31 is located at the position corresponding to the gap between two adjacent first meshing teeth 311.

[0180] As shown in FIG. 24a and FIG. 24b, in some embodiments, a plurality of second meshing teeth 321 are uniformly arranged at intervals at one end of the polish rod joint 32 along a circumferential direction, as the ring gear 35 of the polish rod joint 32, that is, the ring gear 35 for mated plugging is arranged at one end where the sleeve joint 31 and the polish rod joint 32 are connected with each other. The ring gear 35 includes a plurality of first meshing teeth 311 arranged at the end face of the sleeve joint 31 along a circumferential direction and a plurality of second meshing teeth 321 arranged at the end face of the polish rod joint 32 along a circumferential direction, that is, the plurality of first meshing teeth 311 are uniformly arranged at the end face of the sleeve joint 31 along a circumferential direction and the second meshing teeth 321 are uniformly arranged at the end face of the polish rod joint 32 along a circumferential direction. Specifically, since the function of the second meshing teeth 321 is to mesh with the first meshing teeth 311 and transfer torque, the shape of the second meshing teeth 321 matches the shape of the gap between two adjacent first meshing teeth 311. In this embodiment, since the first meshing teeth 311 and the gap therebetween have the same shape, there are also three second meshing teeth 321 with the same shape as the first meshing teeth 311, which is also provided to be fan-shaped, and the fan-shaped angle of the second meshing teeth 321 is 60 degrees, that is, the fan-shaped angle of the second meshing teeth 321 is 60 degrees. A stepped hole for connection with the rotary shaft 21 is provided at one end of the sleeve joint 31 and the polish rod joint 32 away from the ring gear 35, the large diameter portion of the stepped holes is provided to be a round hole corresponding to the rotary shaft 21, and the small diameter portion of the stepped holes is provided to be a square hole corresponding to the rotary shaft 21, wherein the round hole is a circumscribed circle of the square hole. The shape of the stepped hole is similar to that of the stepped hole inside the sleeve joint 31, which will not be described in detail here.

[0181] The positioning rod 34 is provided to be a cylindrical shape, and one end of the positioning rod 34 for plugging into the positioning cylinder 33 is provided to be a hemispherical shape, which is convenient for plugging. The position where the positioning rod 34 is connected with the polish rod joint 32 is located on the second meshing teeth 321. By way of this arrangement, after the positioning rod 34 is plugged with the positioning cylinder 33, the first meshing teeth 311 is exactly plugged with the second meshing teeth 321.

[0182] As shown in FIG. 22, in some embodiments, after the sleeve joint 31 is plugged with the polish rod joint 32, one end of the positioning cylinder 33 proximate to the polish rod joint 32 extends beyond a length range of the polish rod joint 32 towards the direction of the polish rod joint 32. One end of the positioning rod 34 proximate to the sleeve joint 31 extends towards the sleeve joint 31, but the end of the positioning rod 34 is still within the length range of the sleeve joint 31.

[0183] In conjunction with FIGS. 25 and 26, in some embodiments, the positioning cylinder 33 is fixedly connected with the sleeve joint 31 through the first connection block 332. Specifically, the positioning cylinder 33 is fixedly connected with the first connection block 332 by way of welding, and the first connection block 332 is fixedly connected with the sleeve joint 31 by way of welding.

[0184] The positioning rod 34 is fixedly connected with the polish rod joint 32 through the second connection block 341. Specifically, the positioning rod 34 is fixedly connected with the second connection block 341 by way of welding, and the second connection block 341 is fixedly connected with the polish rod joint 32 by way of welding. The cross-sectional shape of the second connection block 341 matches that of the opening groove 331 on the positioning cylinder 33.

[0185] As shown in FIG. 1, in some embodiments, after a plurality of gravity-oriented sensors 2 are connected in series, an upper connector 4 is arranged at the upper end of the second housing 102 of the gravity-oriented sensor 2 at the uppermost end. The upper connector 4 is in the form of a conventional drilling joint, which uses conventional tool joint threads or special joint threads for a screw drilling tool connected with each other in the prior art, and mainly produces the effect of connecting a drilling tool combination. At the same time, the upper end of the gravity-oriented sensor 2 is provided with a fairing cap 5 by way of screw connection. The specific structure of the fairing cap 5 is shown in FIGS. 27a and 27b. In some embodiments, the fairing cap 5 has a cylindrical shape as a whole, and a flange for fixed connection with the fixing ring 28 of the gravity-oriented sensor 2 is arranged at one end of the fairing cap 5. The threaded hole in the flange is provided to be a countersunk hole, and the threaded hole in the flange correspond to the threaded hole in the fixing ring 28 and the threaded hole in the first bearing seat 2701.

[0186] The diameter of the flange of the fairing cap 5 is less than or equal to that of the thin portion of the fixing ring 28. In one preferred embodiment, the diameter of the flange of the fairing cap 5 is equal to that of the thin portion of the fixing ring 28. Therefore, after the fairing cap 5 is mounted on the fixing ring 28, the flange of the fairing cap 5 can be embedded into the fixing ring 28, which can be rapidly mounted and make the structure more stable.

[0187] A cylindrical blind hole with one end for accommodating the rotary shaft 21 is arranged inside one end of the fairing cap 5 where the flange is arranged, and the length and diameter of the cylindrical blind hole are larger than the corresponding size of the rotary shaft 21, so as to leave enough space for installation.

[0188] One end of the fairing cap 5 away from the flange is provided to be a spherical structure. An annular flow channel is formed between the upper connector 4 and the fairing cap 5, which mainly produce the effect of leading the drilling fluid. The spherical structure at the end of the fairing cap 5 is more conducive to the flow of the drilling fluid.

[0189] In another aspect of the present disclosure, a measuring method using the drilling tool face measuring apparatus 100 is provided. The method includes the following steps:

[0190] connecting the drilling tool face measuring apparatus with a drilling tool combination, and calibrating a directional bent sub of the drilling tool combination with the drilling tool face measuring apparatus and then performing running in hole;

[0191] pumping for circulation, and maintaining a stable displacement at a constant certain value, that is, maintaining a stable displacement at a constant predetermined value;

[0192] driving the drilling tool to rotate for one turn, so that the coded disk rotates for one turn relative to the valve block to obtain a pressure pulse signal, that is, forming regular pressure pulse signals, and collecting and analyzing the pressure pulse signal, judging an included angle between a lower side of a wellbore inclination and a reference plane of the drilling tool, so as to implement measuring a current tool face angle;

[0193] causing the rotary drilling tool to continue to rotate for one turn, that is, rotating the drilling tool clockwisely for another turn, and performing double check measurement;

[0194] properly rotating the drilling tool to cause the tool face to swing to a specified position according to a measurement result.

[0195] In other embodiments, the measuring method using the drilling tool face measuring apparatus 100 further includes the following steps:

[0196] designing the coded hole 111 on the coded disk 11 according to the orifice flow theory, that is, designing a pressure pulse and structural parameters of the coded disk 11 according to the orifice flow theory.

[0197] The torque of the gravity-oriented sensor 2, the friction resistance of each bearing and the friction resistance of the coded disk 11 are calculated to form a theoretical calculation system of the driving torque and the friction torque, that is, calculating an eccentric torque, a bearing friction resistance and a coded disk friction resistance of the gravity-oriented sensor under different shapes, different lengths and different materials.

[0198] The drilling tool face measuring apparatus is simulated using a simulation software, and the rationality of theoretical calculations in Steps S6-S8 is verified, that is, simulating a dynamics response of the gravity-oriented sensor, and simulating a waveform of the pressure pulse, so as to select an optimal coding of the coded disk.

[0199] The specific steps of the method for measuring an angle of the drilling tool by using the drilling tool face measuring apparatus in some embodiments are given as follows:

[0200] 1) According to the orifice flow theory, the design of pressure pulses and structural parameters of the coded disk 11 in the pulse generator 1 is completed, and theoretical waveform parameters are obtained by theoretical calculation to form a set of measurement encoded methods,

[0201] wherein, the empirical formula of orifice flow is shown as follows:Δ⁢P=8*ρ*q2Cd2*π2*d4in the formula:

[0203] ΔP: a pressure difference between both sides of the orifice, bar;

[0204] ρ: a density of a fluid medium, g / cm3;

[0205] q: flow volume of an orifice, L / min;

[0206] Cd: a flow coefficient;

[0207] d: a flow aperture, mm.

[0208] It can be seen from the formula that, the pressure difference between both sides of the orifice ΔP and the flow volume q, the flow aperture d, the fluid density ρ and the flow coefficient Cd are directly related, wherein the pressure difference between both sides of the orifice ΔP, the flow volume q and the fluid density ρ are certain values, but the flow coefficient Cd is generally determined according to experiments, and only reference values are given during use. In the case where the liquid flow is completely contracted (l>7d), when the Reynolds coefficient Re≤105, Cd=0.964*Re−0.05. When Re>105, Cd can be regarded as a constant, with a value satisfying Cd=0.6-0.62. When the liquid flow is incompletely contracted, its flow coefficient satisfies Cd≈0.7-0.8.

[0209] According to the empirical formula of orifice flow, the initial design of the solution of the coded disk 11 can be realized to determine the initial design size of each coded hole 111.

[0210] 2) According to the material, shape and length of the gravity-oriented sensor 2, the calculation of its torque, as well as the calculation of the friction resistance of each bearing and the friction resistance of the coded disk are completed to form a theoretical calculation system of a driving torque and a friction torque. This part of theoretical calculation process is the prior art, and calculation can be made by referring to the content in Physics Terminology (2nd Edition), China Science Publishing House.

[0211] 3) The dynamics response of the eccentric weight block 22 and the pressure pulse waveform of the pulse generator 1 are simulated using commercial simulation software such as ADAMS and ANSYS, to verify the rationality of theoretical calculation.

[0212] 4) An optimal coding is preferred to machine and assemble a whole set of equipment, and connect a drilling tool combination.

[0213] 5) After the calibration of the directional bent sub (not shown in the figure) with the drilling tool face measuring apparatus 100 is completed, the drilling tool run in hole in the directional well or the horizontal well. For the calibration process of the directional bend sub with the drilling tool face measuring apparatus 100, reference can be made to the calibration process of the existing directional bend sub with the existing measuring apparatus.

[0214] 6) Pump for circulation, and maintain a stable displacement at a constant certain value.

[0215] 7) The turntable (not shown in the figure) is driven to rotate clockwisely by a wellhead operation, and the drilling tool face measuring apparatus 100 is driven to rotate for one turn, wherein it is the prior art to drive the turntable, which will not be described in detail here.

[0216] 8) Since the valve block 12 is always stabilized at the low side of the wellbore inclination, and the first housing 101 of the pulse generator 1 rotates to drive the coded disk 11 to rotate along a circumferential direction, which results in that the valve block 12 rotates relative to the coded disk 11. The valve block 12 blocks different coded holes 111 of the coded disk 11 sequentially. In the case of a constant flow, the change of the throttling area can lead to the variation of the pressure in the equipment, so as to form regular pressure pulse signal. As shown in FIGS. 28 and 29, according to the aperture of the coded hole 111, the apertures are encoded as 1, 2 and 3 in an ascending sequence. If one coded disk 11 is encoded as 321312, the size of the coded hole 111 is “large, medium, small, large, small and medium” sequentially. When the coded disk 11 rotates, the valve block 12 blocks the six coded holes 111“large, medium, small, large, small and medium” sequentially to obtain the pressure pulse signal curve with the waveform amplitudes which are “high, medium, low, high, low, medium” respectively. Accordingly, a value of a current tool face angle can be judged according to this rule.

[0217] The abscissa in FIG. 28 corresponds to the degree from 0 to 360 degrees on the coded disk 11 in FIG. 29. For the specific calculation method of the tool face angle, reference can be made to the patent with the Patent No. CN110374581B, the invention tile of which is SUPERHIGH-TEMPERATURE MECHANICAL ORIENTING TOOL FACE MEASURING DEVICE AND DESIGN METHOD THEREOF.

[0218] 9) The pressure pulse signal is fed back to the wellhead signal acquisition and monitoring system by means of pressure fluctuation of the riser.

[0219] 10) An included angle between a lower side of a wellbore inclination and a reference plane of the drilling tool is judged by waveform and phase analysis, so as to implement measuring a current tool face angle.

[0220] 11) The drilling tool face measuring apparatus 100 is rotated clockwisely for another turn to perform double check measurement.

[0221] 12) The drilling tool face measuring apparatus 100 is properly rotated to cause the tool face to swing to a specified position according to a measurement result.

[0222] Referring to the content of the embodiments described previously, in one aspect of the present disclosure, a pulse generator is provided.

[0223] The pulse generator includes:

[0224] a first housing;

[0225] a coded disk coaxially and fixedly arranged inside the first housing, wherein a plurality of coded holes with different sizes are uniformly arranged on the coded disk to penetrate through the coded disk along a circumferential direction;

[0226] a valve block arranged to be coaxially and rotatably connected with the coded disk, wherein the valve block is configured to at least partially block at least one coded hole during the rotation, but keep at least another coded hole clear.

[0227] The apparatus in this embodiment can serve as a mechanical directional drilling measuring tool to generate a pressure pulse signal and provide a pressure pulse signal for subsequent tool face position analysis, so as to avoid the use of electronic elements and enable the directional drilling measuring tool to work in a high-temperature environment. In addition, the apparatus can also serve as a tool and equipment to reduce the friction and lessen the resistance during the directional drilling process, and provide pressure pulse vibration for the same.

[0228] In some embodiments, the valve block is connected with a gravity-oriented sensor, wherein the center of gravity of the gravity-oriented sensor does not coincide with the axis of rotation of the valve block, so that the valve block always faces towards one direction under the action of gravity.

[0229] In some embodiments, the first housing is further provided with a key sleeve and a retaining ring, wherein one end of the coded disk axially abuts against the inner wall of the first housing, and the other end of the coded disk abuts against the key sleeve, and the retaining ring abuts against one end of the key sleeve away from the coded disk, and the retaining ring is fixedly connected with the first housing.

[0230] In some embodiments, a plurality of mounting grooves that are axially arranged are uniformly distributed on the inner wall of the first housing along a circumferential direction, and mounting teeth into one-to-one correspondence with the plurality of mounting grooves are arranged on the coded disk and the outer wall of the key sleeve, and one end of the coded disk abuts against the end of the mounting groove through the mounting tooth.

[0231] In some embodiments, a wear-resistant column is coaxially arranged at the end face of the coded disk, and a wear-resistant groove for mated rotationally with the wear-resistant column is arranged at the axis of rotation of the valve block.

[0232] In some embodiments, the valve block is connected with the gravity-oriented sensor through a gravity valve stem and a valve stem joint, wherein a spring is coaxially arranged between the gravity valve stem and the valve stem joint.

[0233] In some embodiments, the valve block is fixedly connected with the gravity valve stem, a stepped hole is arranged at one end of the valve stem joint, the large diameter portion of the stepped hole is located at the outer side and connected with the gravity valve stem by way of plugging, the spring is arranged in the small diameter portion of the stepped hole, and both ends of the spring abut against the gravity valve stem and the valve stem joint respectively.

[0234] In some embodiments, one end of the valve stem joint away from the gravity valve stem is provided with a square hole for connection with the gravity-oriented sensor, and the valve stem joint is provided with a threaded hole penetrating along a radial direction, so that the threaded hole intersects with the square hole.

[0235] In some embodiments, the fan-shaped angles of the coded holes are equal, and a fan-shaped angle of a coded hole of n coded holes is 360° / (2n).

[0236] In some embodiments, the valve blocks are fan-shaped, and an angle of a valve block of the valve blocks is equal to the fan-shaped angle of the coded hole.

[0237] Referring to the content of the embodiments described previously, in one aspect of the present disclosure, a mandrel assembly for a gravity-oriented sensor is provided. The mandrel assembly includes a rotary shaft; a protective shell coaxially sleeved on the rotary shaft; an eccentric weight block fixedly arranged on the rotary shaft, wherein the eccentric weight block is arranged between the rotary shaft and the protective shell, and the eccentric weight block causes the center of gravity of the mandrel assembly to deviate from the axis of rotation of the rotary shaft.

[0238] This embodiment provides a mandrel assembly for a gravity-oriented sensor for a mechanical directional drilling tool, which uses a purely mechanical structure to achieve the stably gravity-oriented effect. The mandrel assembly can not only serve as a drilling measuring tool and instrument, but also serve as a stable platform that needs to stabilize the center of gravity, such as a rotary navigator drilling studio and a vertical drilling tool. This embodiment avoids the use of an electronic element, thereby improving an endurable working temperature.

[0239] In some embodiments, an annular blind end is arranged at the inner side of the end of the protective shell, the end of the eccentric weight block axially abuts against the annular blind end, and a plurality of mounting pins for connection with the eccentric weight block are uniformly arranged on the annular blind end along a circumferential direction.

[0240] In some embodiments, the rotary shaft is coaxially provided with two cover plates arranged at both ends of the eccentric weight block respectively, and the outer ends of the cover plates axially extend towards the eccentric weight block, so that the outer wall of the eccentric weight block radially abuts against the cover plate, and the cover plate axially abuts against the annular blind end of the protective shell to prevent the mounting pin from disengagement.

[0241] In some embodiments, the rotary shaft is provided with a second boss for cooperating with the cover plate, and the cover plate is coaxially sleeved on the second boss through a second flat key located proximate to the eccentric weight block.

[0242] In some embodiments, the thickness of the cover plate is less than that of the second boss.

[0243] In some embodiments, the eccentric weight block includes two semi-cylindrical shapes with the same volume, which fixedly enclose the outer wall of the rotary shaft, wherein one of the two semi-cylindrical eccentric weight blocks is formed of a high-density material and the other is formed of a low-density material.

[0244] In some embodiments, a clamping block is fixedly connected to the outer wall of the rotary shaft, and the eccentric weight block is provided with a clamping groove for clamping with the clamping block; each of the eccentric weight blocks corresponds to one of the clamping blocks presenting a strip shape and arranged along a generatrix of the rotary shaft.

[0245] In some embodiments, the clamping blocks are divided into three sections with equal length and uniformly arranged on the outer wall of the rotary shaft.

[0246] In some embodiments, the clamping block is fixedly connected with the rotary shaft by means of bolt connection.

[0247] In some embodiments, the clamping block is fixedly connected with the rotary shaft by means of integral formation.

[0248] Referring to the content of the embodiments described previously, in one aspect of the present disclosure, a mandrel assembly for a gravity-oriented sensor is provided. The mandrel assembly includes:

[0249] a rotary shaft; and

[0250] an eccentric weight block fixedly arranged on the rotary shaft, wherein the eccentric weight block causes the center of gravity of the mandrel assembly to deviate from the axis of rotation of the rotary shaft.

[0251] This embodiment provides a mandrel assembly for a gravity-oriented sensor for a mechanical directional drilling tool, which uses a purely mechanical structure to achieve the stably gravity-oriented effect. The mandrel assembly can not only serve as a drilling measuring tool and instrument, but also serve as a stable platform that needs to stabilize the center of gravity, such as a rotary navigator drilling studio and a vertical drilling tool.

[0252] In some embodiments, the eccentric weight block includes two semi-cylindrical shapes with the same volume, which fixedly enclose the outer wall of the rotary shaft, wherein one of the two semi-cylindrical eccentric weight blocks is formed of a high-density material and the other is formed of a low-density material.

[0253] In some embodiments, a clamping block is fixedly connected to the outer wall of the rotary shaft, and the eccentric weight block is provided with a clamping groove for clamping with the clamping block. In some embodiments, each of the eccentric weight blocks corresponds to one of the clamping blocks presenting a strip shape and arranged along a generatrix of the rotary shaft.

[0254] In some embodiments, the clamping blocks are divided into three sections with equal length and uniformly arranged on the outer wall of the rotary shaft.

[0255] In some embodiments, the clamping block is fixedly connected with the rotary shaft by means of bolt connection.

[0256] In some embodiments, the clamping block is fixedly connected with the rotary shaft by means of integral formation.

[0257] In some embodiments, the rotary shaft is coaxially provided with two cover plates arranged at both ends of the eccentric weight block respectively, and the outer ends of the cover plates axially extend towards the direction of the eccentric weight block, so that the outer wall of the eccentric weight block radially abuts against the cover plate.

[0258] In some embodiments, the rotary shaft is provided with a second boss for cooperating with the cover plate, and the cover plate is coaxially sleeved on the second boss through a second flat key located proximate to the eccentric weight block.

[0259] In some embodiments, the thickness of the cover plate is less than that of the second boss.

[0260] Referring to the content of the embodiments described previously, in one aspect of the disclosure, a mandrel connector is provided for connection with the rotary shafts of two adjacent gravity-oriented sensors, including a sleeve joint and a polish rod joint, wherein a ring gear for mated plugging is arranged at one end where the sleeve joint and the polish rod joint are connected with each other, a positioning cylinder is arranged at the edge of the sleeve joint, and a positioning rod for plugging with the positioning cylinder is arranged at the edge of the polish rod joint.

[0261] This embodiment provides a gravity-oriented sensor for a mechanical directional drilling tool, which enables two purely mechanical gravity-oriented sensors to be positioned and connected with each other and transfer torque, and the mandrel assembly is connected with the second housing through the bearing seat assembly, so that it is possible to ensure that the annular space between the mandrel assembly and the second housing circulates the drilling fluid, and at the same time protect a bearing in the bearing seat assembly and present a favorable sealing property. This embodiment can not only serve as a drilling measuring tool and instrument, but also serve as a stable platform that needs to stabilize the center of gravity, such as a rotary navigator drilling studio and a vertical drilling tool.

[0262] In some embodiments, the sleeve joint and the polish rod joint are in a cylindrical shape, and the ring gear includes a plurality of first meshing teeth uniformly arranged on the end face of the sleeve joint and a plurality of second meshing teeth uniformly arranged on the end face of the polish rod joint along a circumferential direction.

[0263] In some embodiments, the shape of the gap between the adjacent first meshing teeth matches the shape of the second meshing teeth.

[0264] In some embodiments, the numbers of the first meshing teeth and the second meshing teeth are both three.

[0265] In some embodiments, the cross-sections of the first meshing teeth and the second meshing teeth are fan-shaped, and the fan-shaped angles of the first meshing teeth and the second meshing teeth are 60 degrees.

[0266] In some embodiments, a stepped hole for connection with the rotary shaft is arranged at one end of the sleeve joint and the polish rod joint away from the ring gear.

[0267] In some embodiments, the large diameter portion of the stepped holes is provided to be a round hole corresponding to the rotary shaft, and the small diameter portion of the stepped holes is provided to be a square hole corresponding to the rotary shaft.

[0268] In some embodiments, the round hole is a circumscribed circle of the square hole.

[0269] In some embodiments, the positioning cylinder is fixedly connected with the sleeve joint through a first connection block, and the positioning rod is fixedly connected with the polish rod joint through a second connection block.

[0270] In some embodiments, the cylinder wall of the positioning cylinder is provided with an open slot through which the second connection block passes along a generatrix direction.

[0271] Referring to the content of the embodiments described previously, in one aspect of the present disclosure, a gravity-oriented sensor is provided. The gravity-oriented sensor includes: a second housing; a mandrel assembly coaxially and rotatably arranged in the second housing, wherein the mandrel assembly is configured such that the center of gravity does not coincide with the axis of rotation, and an annular space is provided between the mandrel assembly and the second housing; a bearing seat assembly arranged in the second housing, wherein the bearing seat assembly is arranged at both ends of the mandrel assembly, and the bearing seat assembly is provided with a first flow hole penetrating radially.

[0272] This embodiment provides a gravity-oriented sensor for a mechanical directional drilling tool, which uses a purely mechanical structure to achieve the stably gravity-oriented effect. The gravity-oriented sensor is connected with the second housing through the bearing seat assembly, so that it is possible to ensure that the annular space between the mandrel assembly and the second housing circulates the drilling fluid, and at the same time protect a bearing in the bearing seat assembly and present a favorable sealing property. This embodiment can not only serve as a drilling measuring tool and instrument, but also serve as a stable platform that needs to stabilize the center of gravity, such as a rotary navigator drilling studio and a vertical drilling tool.

[0273] In some embodiments, the bearing seat assembly is internally provided with a stepped hole for mounting a bearing, and one open end of the stepped hole faces towards the mandrel assembly.

[0274] In some embodiments, both ends of the mandrel assembly are provided with a sealing plate cooperating with the bearing seat assembly to seal the stepped hole of the bearing seat assembly, thereby protecting a bearing in the bearing seat assembly.

[0275] In some embodiments, a sealing ring coaxially rotating and sealing with each other is arranged on a mating surface of the sealing plate and the bearing seat assembly, and the size of the sealing ring is larger than that of the stepped hole of the bearing seat assembly.

[0276] In some embodiments, the number of the first flow holes is three, which are uniformly arranged on the bearing seat assembly along a circumferential direction, and the size of a circle surrounded by the first flow holes is larger than that of the sealing ring.

[0277] In some embodiments, the first flow hole is provided to be fan-shaped. In some embodiments, a fixing ring is fixedly arranged at one end of the bearing seat assembly away from the mandrel assembly, and the fixing ring is fixedly connected with the second housing.

[0278] In some embodiments, a second flow hole corresponding to the first flow hole is arranged on the fixing ring 28 to radially penetrate through the fixing ring.

[0279] In some embodiments, the second flow hole is provided to be fan-shaped, and the fan-shaped angle of the second flow hole is larger than that of the first flow hole.

[0280] In some embodiments, the bearing seat assembly at the upper end of the mandrel assembly is internally provided with a spherical roller bearing, and the bearing seat assembly at the lower end of the mandrel assembly is internally provided with a radial bearing and a thrust bearing.

[0281] Referring to the content of the embodiments described previously, in one aspect of the present disclosure, a drilling tool face measuring apparatus is provided, which is connected above a drill bit. The drilling tool face measuring apparatus includes:

[0282] an outer cylinder configured to rotate synchronously with the drill bit;

[0283] a coded disk coaxially and fixedly arranged inside the first housing, wherein a plurality of coded holes with different sizes are uniformly arranged on the coded disk along a circumferential direction to penetrate through the coded disk;

[0284] a valve block arranged to be coaxially and rotatably connected with the coded disk, wherein the valve block is configured to at least partially block at least one coded hole during the rotation, but keep at least another coded hole clear;

[0285] a gravity-oriented sensor connected with the valve block, wherein the center of gravity of the gravity-oriented sensor does not coincide with the axis of rotation of the valve block, so that the valve block always faces towards one direction under the action of gravity.

[0286] The present disclosure uses a purely mechanical structure to replace the measurement-while-drilling tool for measuring the tool face using an electronic element in the prior art, so that its endurable temperature is much higher than that of the measurement-while-drilling tool using an electronic element in the prior art, so as to overcome the problem that the measurement-while-drilling tool in the related art fail to work normally under high-temperature working conditions. Moreover, the coded disk rotates along with the drill bit, a plurality of coded holes are circumferentially arranged on the coded disk, and the valve block for blocking the coded holes always faces towards the lower side of the wellbore inclination under the action of the gravity-oriented sensor, so that the valve block can rotate relative to the coded holes and generate different pressure pulses. According to the pressure pulse, it is possible to judge the angle of the tool face, so as to adjust the drilling direction.

[0287] In some embodiments, the gravity-oriented sensor includes a rotary shaft connected with the valve block, and the outer wall of the rotary shaft is provided with an eccentric weight block, which causes that the axis of rotation of the gravity-oriented sensor does not coincide with the center of gravity.

[0288] In some embodiments, the drilling tool face measuring apparatus includes a plurality of gravity-oriented sensors connected with each other through a mandrel connector, and a straight line passing through the centers of gravity of the plurality of gravity-oriented sensors is parallel to the axes of rotation of the plurality of gravity-oriented sensors.

[0289] In some embodiments, the outer cylinder is further internally provided with a key sleeve and a retaining ring, a plurality of mounting grooves that are axially arranged are uniformly distributed on the inner wall of the outer cylinder along a circumferential direction, the coded disk and the outer wall of the key sleeve are provided with a plurality of mounting teeth in one-to-one correspondence with the plurality of mounting grooves, one end of the coded disk abuts against the end of the mounting groove through the mounting teeth, the other end of the coded disk abuts against the key sleeve, the retaining ring is abuttingly arranged at one end of the key sleeve away from the coded disk, and the retaining ring is fixedly connected with the outer cylinder.

[0290] In some embodiments, a wear-resistant column is coaxially arranged at the end face of the coded disk, and a wear-resistant groove for mated rotationally with the wear-resistant column is arranged at the axis of rotation of the valve block.

[0291] In some embodiments, the valve block is connected with the gravity-oriented sensor through a gravity valve stem and a valve stem joint, wherein a spring is coaxially arranged between the gravity valve stem and the valve stem joint.

[0292] In some embodiments, the valve block is fixedly connected with the gravity valve stem, a stepped hole is arranged at one end of the valve stem joint, the large diameter portion of the stepped hole is located at the outer side and connected with the gravity valve stem by way of plugging, the spring is arranged in the small diameter portion of the stepped hole, and both ends of the spring abut against the gravity valve stem and the valve stem joint respectively.

[0293] In some embodiments, one end of the valve stem joint away from the gravity valve stem is provided with a square hole for connection with the gravity-oriented sensor, and the valve stem joint is provided with a threaded hole penetrating along a radial direction, so that the threaded hole intersects with the square hole.

[0294] In some embodiments, the fan-shaped angles of the coded holes are equal, and the fan-shaped angles of n coded holes are 360° / (2n), and the valve blocks are fan-shaped, and the angles of the valve blocks are equal to the fan-shaped angles of the coded holes.

[0295] In some embodiments, the eccentric weight block includes two semi-cylinders with equal volumes enclosing the rotary shaft, one of which is formed of a low-density material, and the other is formed of a high-density material.

[0296] In some embodiments, a clamping block is fixedly connected to the outer wall of the rotary shaft, and the eccentric weight block is provided with a clamping groove for clamping with the clamping block.

[0297] In some embodiments, the rotary shaft is coaxially provided with two cover plates arranged at both ends of the eccentric weight block respectively, and the outer ends of the cover plates axially extend towards the direction of the eccentric weight block, so that the outer wall of the eccentric weight block radially abuts against the cover plate.

[0298] In some embodiments, the rotary shaft is provided with a second boss for cooperating with the cover plate, and the cover plate is coaxially sleeved on the second boss through a second flat key located proximate to the eccentric weight block.

[0299] In some embodiments, both ends of the rotary shaft are connected with the outer cylinder through a bearing, and the outer cylinder is internally provided with a bearing seat assembly for mounting a bearing, and a plurality of first flow holes are uniformly arranged on the bearing seat assembly along a circumferential direction, so that the first flow holes are located circumferentially outside the bearing.

[0300] In some embodiments, the outer cylinder is further internally provided with a fixing ring fixedly connected with the bearing seat assembly, so that the fixing ring is arranged on one side of the bearing seat assembly away from the eccentric weight block, and a plurality of second flow holes corresponding to the first flow holes are uniformly arranged on the fixing ring along a circumferential direction, and the dimensions of the second flow holes are larger than the first flow holes.

[0301] In some embodiments, the bearing seat assembly is internally provided with a radial bearing and a thrust bearing, the thrust bearing is closer to the eccentric weight block than the radial bearing, and a bearing retaining ring is arranged between the thrust bearing and the radial bearing.

[0302] In some embodiments, the mandrel connector includes a sleeve joint and a polish rod joint, a ring gear for mated plugging is arranged at one end where the sleeve joint and the polish rod joint are connected with each other, a positioning cylinder is arranged at the edge of the sleeve joint, and a positioning rod for plugging with the positioning cylinder is arranged at the edge of the polish rod joint.

[0303] In some embodiments, an upper connector is provided at one end of the outer cylinder away from the drill bit, and a fairing cap is provided at one end of the rotary shaft away from the drill bit, one end of the fairing cap away from the rotary shaft is provided to be a spherical surface, and a drilling fluid channel is formed between the fairing cap and the upper connector.

[0304] In one aspect of the present disclosure, a method for measuring a drilling tool angle by using the drilling tool face measuring apparatus described previously is provided. The method includes the following steps:

[0305] S1. The coded holes on the coded disk are designed according to the orifice flow theory;

[0306] S2. The torque of the gravity-oriented sensor, the friction resistance of each bearing and the friction resistance of the coded disk are calculated to form a theoretical calculation system of the driving torque and the friction torque;

[0307] S3. The drilling tool face measuring apparatus is simulated by using the simulation software, and the rationality of theoretical calculations in Step S1 and Step S2 is verified;

[0308] S4. The drilling tool face measuring apparatus is connected with a drilling tool combination, and a directional bent sub of the drilling tool combination is calibrated with the drilling tool face measuring apparatus to perform running in hole;

[0309] S5. Pump for circulation, and maintain a stable displacement at a constant certain value.

[0310] S6. The drilling tool is driven to rotate for one turn, so that the coded disk rotates for one turn relative to the valve block to obtain regular pressure pulse signals;

[0311] the pressure pulse signals are collected and analyzed, and an included angle between a lower side of a wellbore inclination and a reference plane of the drilling tool is judged so as to implement measuring a current tool face angle;

[0312] S7. The drilling tool is rotated clockwisely for another turn to perform double check measurement;

[0313] S8. The drilling tool is properly rotated to cause the tool face to swing to a specified position according to a measurement result.

[0314] In the description of the present disclosure, it should be understood that, the terms “first” and “second” are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined as “first” and “second” may include one or more of these features explicitly or implicitly.

[0315] In the description of the present disclosure, “a plurality of” means two or more, unless otherwise specifically defined.

[0316] In the present disclosure, unless otherwise specified and limited, the terms “mounted”, “connected to”, “connected with” and “fixed” should be broadly understood, and for example, may be fixedly connected or detachably connected or integrally connected; may be mechanically connected or electrically connected; may be directly connected or indirectly connected through an intermediate medium, and may be communication inside two elements. For those skilled in the art, the specific meanings of the above-described terms in the present disclosure may be understood according to specific conditions.

[0317] In the description of this specification, descriptions referring to the terms such as “one embodiment”, “some embodiments”, “examples”, “specific examples” or “some examples” mean that specific features, structures, materials or characteristics described in connection with this embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic expressions of the above-described terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0318] Finally, it should be noted that, the above is only the preferred embodiment of the present disclosure, and does not constitute any restriction on the present disclosure. Although the present disclosure has been described in detail with reference to the embodiments described previously, it is still possible for those skilled in the art to modify the technical solution recited in the embodiments described previously or to replace some of the technical features with equivalents. Any modification, equivalent substitution, improvement and the like made within the spirit and principles of the present disclosure should be included in the protection scope of the present disclosure.

Claims

1. A drilling tool face measuring apparatus for connection with a drill bit, wherein the drilling tool face measuring apparatus comprises:an outer cylinder (10) configured to rotate synchronously with the drill bit;a coded disk (11) fixedly arranged inside the outer cylinder (10) and having a plurality of coded holes (111) axially penetrating through the coded disk (11) and arranged in a circumferential direction;a valve block (12) configured to rotate coaxially relative to the coded disk (11), and open and close different coded holes (111) among the plurality of coded holes (111) at various rotational positions relative to the coded disk (11); anda gravity-oriented sensor (2) rotatably arranged inside the outer cylinder (10) and connected to the valve block (12), wherein a center of gravity of the gravity-oriented sensor (2) does not coincide with an axis of rotation of the valve block (12), and the gravity-oriented sensor (2) is configured to drive the valve block (12) to rotate synchronously about the axis of rotation of the valve block (12), so that the gravity-oriented sensor (2) causes the valve block (12) to maintain an orientation relative to the axis of rotation of the valve block (12) under action of gravity.

2. (canceled)3. The drilling tool face measuring apparatus according to claim 1,wherein the gravity-oriented sensor (2) comprises a rotary shaft (21) connected with the valve block (12), and an outer wall of the rotary shaft (21) is provided with an eccentric weight block (22), which causes that the axis of rotation of the gravity-oriented sensor (2) does not coincide with the center of gravity.

4. The drilling tool face measuring apparatus according to claim 3, wherein both ends of the rotary shaft (21) are connected with the outer cylinder (10) through a bearing, and the outer cylinder (10) is internally provided with a bearing seat assembly (27) for mounting the bearing, and the bearing seat assembly (27) is provided with a plurality of first flow holes (271) uniformly arranged in a circumferential direction, so that the first flow holes (271) are located circumferentially outside the bearing.

5. The drilling tool face measuring apparatus according to claim 4, wherein the outer cylinder (10) is further internally provided with a fixing ring (28) fixedly connected with the bearing seat assembly (27), the fixing ring (28) is arranged on one side of the bearing seat assembly (27) away from the eccentric weight block (22), and the fixing ring (28) is provided with a plurality of second flow holes (281) corresponding to the first flow holes (271), the plurality of second flow holes (281) are uniformly arranged in a circumferential direction, and a cross-sectional dimension of the second flow holes (281) are larger than that of the first flow holes (271).6-12. (canceled)13. The drilling tool face measuring apparatus according to claim 3, wherein the rotary shaft (21) is coaxially provided with two cover plates (24) arranged at both ends of the eccentric weight block (22) respectively, and outer ends of the cover plates (24) axially extend towards the eccentric weight block (22), so that an outer wall of the eccentric weight block (22) radially abuts against the cover plate (24).

14. The drilling tool face measuring apparatus according to claim 13, wherein the rotary shaft (21) is provided with a second boss (25) for cooperating with the cover plate (24), the cover plate (24) is coaxially sleeved on the second boss (25) through a second flat key (26) located proximate to the eccentric weight block (22).

15. (canceled)16. The drilling tool face measuring apparatus according to claim 3, wherein a clamping block (23) is fixedly connected to the outer wall of the rotary shaft (21), and the eccentric weight block (22) is provided with a clamping groove for clamping with the clamping block (23).17-19. (canceled)20. The drilling tool face measuring apparatus according to claim 1, wherein the drilling tool face measuring apparatus comprises a plurality of gravity-oriented sensors (2) connected with each other through a mandrel connector (3), and a straight line passing through centers of gravity of the plurality of gravity-oriented sensors (2) is parallel to axes of rotation of the plurality of gravity-oriented sensors (2).

21. The drilling tool face measuring apparatus according to claim 20, wherein the mandrel connector (3) comprises a sleeve joint (31) and a polish rod joint (32), a ring gear (35) for mated plugging is arranged at one end where the sleeve joint (31) and the polish rod joint (32) are connected with each other, a positioning cylinder (33) is arranged at an edge of the sleeve joint (31), and a positioning rod (34) for plugging with the positioning cylinder (33) is arranged at an edge of the polish rod joint (32).

22. The drilling tool face measuring apparatus according to claim 21, wherein the sleeve joint (31) and the polish rod joint (32) are in a cylindrical shape, and the ring gear (35) comprises a plurality of first meshing teeth (311) arranged on an end face of the sleeve joint (31) in a circumferential direction and a second meshing teeth arranged at an end face of the polish rod joint (32) in a circumferential direction.23-25. (canceled)26. The drilling tool face measuring apparatus according to claim 21, wherein a stepped hole for connection with the rotary shaft (21) is arranged at one end of the sleeve joint (31) and the polish rod joint (32) away from the ring gear (35).

27. The drilling tool face measuring apparatus according to claim 21, wherein the positioning cylinder (33) is fixedly connected with the sleeve joint (31) through a first connection block (332), and the positioning rod (34) is fixedly connected with the polish rod joint (32) through a second connection block (341).

28. The drilling tool face measuring apparatus according to claim 27, wherein the cylinder wall of the positioning cylinder (33) is provided with an open slot (331) which extends along a generatrix direction and through which the second connection block (341) passes.

29. (canceled)30. The drilling tool face measuring apparatus according to claim 1, wherein an inner wall of the outer cylinder (10) is provided with a plurality of mounting grooves arranged along a circumferential direction and extending along an axial direction, the coded disk (11) is provided with a plurality of mounting teeth in one-to-one correspondence with the plurality of mounting grooves, and the coded disk (11) is fixed inside the outer cylinder (10) by embedding the plurality of mounting teeth into the plurality of mounting grooves.

31. The drilling tool face measuring apparatus according to claim 30, wherein the outer cylinder (10) is further internally provided with a key sleeve (13) and a retaining ring (14), an outer wall of the key sleeve (13) is provided with a plurality of mounting teeth in one-to-one correspondence with the plurality of mounting grooves, one end of the coded disk (11) abuts against an end of the mounting grooves, the other end of the coded disk (11) abuts against the key sleeve (13), the retaining ring (14) is arranged at one end of the key sleeve (13) away from the coded disk (11) in an abutting manner, and the retaining ring (14) is fixedly connected with the outer cylinder (10).

32. The drilling tool face measuring apparatus according to claim 1, wherein a wear-resistant column (15) is coaxially arranged at an end face of the coded disk (11), and a wear-resistant groove (16) for mated rotationally with the wear-resistant column (15) is arranged at the axis of rotation of the valve block (12).

33. The drilling tool face measuring apparatus according to claim 1, wherein the valve block (12) connects the gravity-oriented sensor (2) through a gravity valve stem (17) and a valve stem joint (18), the gravity valve stem (17) is movable along an axial direction relative to the valve stem joint (18), and an elastic member is provided between the gravity valve stem (17) and the valve stem joint (18).

34. The drilling tool face measuring apparatus according to claim 33, wherein the valve block (12) is fixedly connected with the gravity valve stem (17), one end of the valve stem joint (18) adjacent to the gravity valve stem (17) is provided with a stepped hole having a first hole section and a second hole section, the second hole section is located inside the first hole section, and a cross-sectional dimension of the first hole section is larger than that of the second hole section, the first hole section is connected with the gravity valve stem (17) through a flat key, and the elastic member comprises a spring (19) arranged in the second hole section, and both ends of the spring (19) abut against the gravity valve stem (17) and the valve stem joint (18) respectively.35-46. (canceled)47. A method for measuring a drilling tool angle by using the drilling tool face measuring apparatus according to claim 1, comprising the following steps:connecting the drilling tool face measuring apparatus with a drilling tool combination, and calibrating a directional bent sub of the drilling tool combination with the drilling tool face measuring apparatus and then performing running in hole;pumping for circulation, and maintaining a stable displacement at a constant predetermined value;driving the drilling tool to rotate for one turn, so that the coded disk rotates for one turn relative to the valve block to obtain a pressure pulse signal;collecting and analyzing the pressure pulse signal, judging an included angle between a lower side of a wellbore inclination and a reference plane of the drilling tool, so as to implement measuring a current tool face angle;causing the rotary drilling tool to continue to rotate for one turn, and performing double check measurement; androtating the drilling tool to cause the tool face to swing to a specified position according to a measurement result.

48. The drilling tool face measuring method according to claim 47, further comprising the following steps:designing a pressure pulse and structural parameters of the coded disk according to the orifice flow theory;calculating an eccentric torque, a bearing friction and a coded disk friction of the gravity-oriented sensor under different shapes, different lengths and different materials; andsimulating a dynamics response of the gravity-oriented sensor, and simulating a waveform of the pressure pulse, so as to select an optimal coding of the coded disk.

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