Device and method for measuring angle of working surface of drilling tool

Abstract

FIELD: drilling tools.SUBSTANCE: group of inventions relates to a device and method for measuring the angle of inclination of the working surface of a drilling tool. The device for measuring the angle of inclination of the working surface of a drilling tool comprises an outer cylinder, a coded disk, a valve block and a gravity-type orientation sensor. The outer cylinder is configured to rotate synchronously with the drill bit. The coded disc is rigidly located inside the outer cylinder and has several coded holes passing axially through the coded disc and located in the circumferential direction. The valve block is configured to rotate coaxially relative to the coded disk and to open and close various coded openings from said coded openings in various rotation positions relative to the coded disk. The gravity-type orientation sensor is configured to rotate within the outer cylinder and is connected to the valve block. The centre of gravity of the specified sensor does not coincide with the axis of rotation of the valve block. The gravity-type orientation sensor is configured to actuate the valve block for synchronous rotation around the axis of rotation of the valve block, so that said sensor can maintain the orientation of the valve block relative to the axis of rotation of the valve block under the action of gravity. The inner wall of the outer cylinder has several mounting grooves located along the circumferential direction and extending in the axial direction. The coded disk has several mounting teeth that correspond one-to-one to the specified mounting grooves. The coded disk is secured inside the outer cylinder by inserting said mounting teeth into said mounting grooves.EFFECT: solving the problem of failure of the measuring instrument during drilling under high temperature conditions encountered during deep and ultra-deep well drilling and geothermal resource development.19 cl, 29 dwg

Description

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] This application is based on and claims priority from Chinese Patent Applications Nos. 202310050113.1, 202310050112.7, 202310050117.X, 202310050115.0, 202310050118.4 and 202310050119.9, filed on February 1, 2023, the contents of which are incorporated herein by reference in their entirety.TECHNICAL FIELD

[0002] The present invention relates to the field of drilling oil and gas wells, in particular to a device for measuring the working surface of a drilling tool and a measurement method using the device for measuring the working surface of a drilling tool. BACKGROUND

[0003] With the development of oil and gas exploration and development and the focus on deep and ultra-deep well drilling technology, exploration volumes are currently growing, and the proportion of deep wells in total well completions is increasing year by year. Multi-well drilling depths exceed 8,000 m, and the measured bottomhole temperature in most cases exceeds 200°C. In some areas, the geothermal gradient is high (3.3~3.82°C / 100m), causing deep well drilling temperatures to be high, and the projected bottomhole temperature exceeds 230°C.However, during deep-well construction, whether using a high-temperature rotary pulse MWD (downhole measurement while drilling) system or an existing drilling company's high-temperature pulse MWD, these drilling tools are essentially electronic components. Their actual allowable temperature is generally below 180°C, and the instrument data is unstable. They do not function properly under operating conditions where the bottomhole temperature is excessively high, which seriously impacts the drilling structures. Therefore, oil and gas exploration and development are faced with the challenge of directional drilling in ultra-high-temperature formations.

[0004] The development and exploitation of hot dry rock resources is rapidly developing. Currently, the temperature of hot dry rock, which is favorable for development in related fields, exceeds 200°C, and directional well construction is often used. Therefore, deep and ultra-deep well drilling, as well as the development and exploitation of hot dry rock resources, are faced with the problem of the ineffectiveness of existing drilling measurement tools in high-temperature conditions.

[0005] There are several patents or patent applications known in the art that disclose various devices and methods for measuring the inclination angle of the working surface of a drilling tool. For example, Chinese Patent Application CN 114427433 A discloses a device for measuring the working surface of a downhole equipment based on mechanical pressure adjustment. The device for measuring the working surface of a downhole equipment has an outer cylinder; an encoded mechanism is housed in the outer cylinder and comprises an encoded disk and a valve block, the encoded disk is fixed in the outer cylinder and has throttling holes, and the valve block can rotate relative to the encoded disk and close a part of the throttling holes; the lower end of the mechanical energy-sensitive device is connected to the valve block, and the mechanical energy-sensitive device maintains its position under the action of gravity;when the outer cylinder rotates, the coded disk also begins to rotate and the mechanical energy sensitive device ensures that the valve block is held in one position under the action of gravity, so that the valve block continuously opens and closes the various throttling holes of the coded disk, thereby generating pressure wave signals by which the position of the working surface of the tool in question can be determined. ESSENCE OF THE INVENTION;

[0006] In view of the above technical problem, the object of the present invention is to provide a device for measuring the working surface of a drilling tool, which uses a purely mechanical structure that can operate normally under high temperature conditions.

[0007] The present invention also provides a measurement method using a device for measuring the working surface of a drilling tool that can operate normally under high temperature conditions.

[0008] In one aspect of the present invention, a device for measuring the working surface of a drilling tool is provided, intended for connection with a drill bit, wherein the device for measuring the working surface of a drilling tool comprises: an outer cylinder configured to rotate synchronously with the drill bit, a coded disk rigidly mounted inside the outer cylinder and having a plurality of coded openings passing in the axial direction through the coded disk and located in the circumferential direction, a valve block configured to coaxially rotate relative to the coded disk and open and close various coded openings from said coded openings in different positions of rotation relative to the coded disk, and a gravity-type orientation sensor mounted with the possibility of rotation inside the outer cylinder and connected to the valve block,wherein the center of gravity of said sensor does not coincide with the axis of rotation of the valve block, and the sensor itself is designed with the possibility of activating the valve block for synchronous rotation around the axis of rotation of the valve block, so that said sensor ensures the possibility of maintaining the orientation of the valve block relative to the axis of rotation of the valve block under the action of gravity.

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

[0010] In some embodiments, the gravity-type orientation sensor comprises a rotary shaft connected to a valve block, wherein the outer wall of the rotary shaft has an eccentric weight block, as a result of which the axis of rotation of said sensor does not coincide with the center of gravity.

[0011] In some embodiments, both ends of the rotary shaft are connected to the outer cylinder through a bearing, wherein the outer cylinder has a bearing seat assembly inside for installing a bearing, wherein the bearing seat assembly has several first flow holes, uniformly spaced in the circumferential direction, so that these holes are located circumferentially outside the bearing.

[0012] In some embodiments, the outer cylinder additionally has a retaining ring on the inside, rigidly connected to the bearing seat assembly, wherein the retaining ring is located on one side of said assembly away from the eccentric weight block, wherein the retaining ring has several second flow holes corresponding to the first flow holes, wherein said second flow holes are uniformly distributed in the circumferential direction, and the size of their cross-section is larger than that of the first flow holes.

[0013] In some embodiments, the bearing seat assembly has a radial bearing and a thrust bearing inside, wherein the thrust bearing is located closer to the eccentric weight block than the radial bearing, and the bearing retaining ring is located between the thrust bearing and the radial bearing.

[0014] In some embodiments, an upper connector is located at one end of the outer cylinder away from the drill bit, and a fairing is located at one end of the rotary shaft away from the drill bit, wherein one end of the fairing away from the rotary shaft is formed in the form of a spherical surface, and a channel for drilling fluid is formed between the fairing and the upper connector.

[0015] In some embodiments, the gravity-type orientation sensor has a mandrel assembly comprising a rotary shaft and an eccentric weight block rigidly fixed to the rotary shaft, wherein the eccentric weight block allows the center of gravity of the gravity-type orientation sensor to deviate from the axis of rotation of the rotary shaft.

[0016] In some embodiments, the gravity-type orientation sensor has a mandrel assembly containing a rotary shaft, a protective shell coaxially placed on the rotary shaft, and an eccentric weight block rigidly fixed on the rotary shaft, wherein the eccentric weight block is located between the rotary shaft and the protective shell and allows the center of gravity of the unbalanced sensor to deviate from the axis of rotation of the rotary shaft.

[0017] In some embodiments, an annular blind end is located on the inner side of the end of the protective shell, against which the end of the eccentric weight block rests in the axial direction, wherein the annular blind end has several mounting pins for connection with the eccentric weight block, and said several mounting pins are uniformly spaced in the circumferential direction.

[0018] In some embodiments, the rotary shaft has two cover plates coaxially located, respectively, at both ends of the eccentric weight block, and the outer ends of the cover plates axially protrude in the direction of the eccentric weight block, so that the outer wall of the eccentric weight block radially abuts the cover plates, and the cover plates axially abut the annular blind end of the protective shell, preventing the disconnection of the mounting pin.

[0019] In some embodiments, the eccentric weight block comprises two half-cylinders of equal volumes enclosing the rotary shaft, one of which is made of a first material and the other of a second material, wherein the density of the second material is greater than the density of the first material.

[0020] In some embodiments, the rotary shaft has two cover plates coaxially located, respectively, at both ends of the eccentric weight block, and the outer ends of the cover plates axially extend toward the eccentric weight block, so that the outer wall of the eccentric weight block radially abuts against the cover plate.

[0021] In some embodiments, the rotary shaft has a second projection for interacting with the cover plate, wherein the cover plate is coaxially mounted on the second projection by means of a second flat key located near the eccentric weight block.

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

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

[0024] In some embodiments, each block of eccentric weights corresponds to one of the clamping blocks, which are strip-shaped and extend along the generatrix of the rotary shaft.

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

[0026] In some embodiments, the clamping block is rigidly connected to the rotary shaft by means of a bolted connection or made as a single unit.

[0027] In some embodiments, the device for measuring the working surface of a drilling tool comprises several gravity-type orientation sensors connected to each other via a mandrel connector, wherein a straight line passing through the centers of gravity of said gravity-type orientation sensors is parallel to the axes of rotation of said sensors.

[0028] In some embodiments, the mandrel connector comprises a coupling connection and a polished rod connection, a gear transmission for mating locking, located at one end, where the coupling connection and the polished rod connection are connected to each other, a positioning cylinder located at the edge of the coupling connection, and a positioning rod for locking with the positioning cylinder, located at the edge of the polished rod connection.

[0029] In some embodiments, the coupling connection and the polished rod connection have a cylindrical shape, and the gear transmission comprises several first engaging teeth located on the end surface of the coupling connection in the circumferential direction, and second engaging teeth located on the end surface of the polished rod connection in the circumferential direction.

[0030] In some embodiments, the shape of the gap between adjacent first engaging teeth corresponds to the shape of the second engaging teeth.

[0031] In some embodiments, the number of first and second teeth is three.

[0032] In some embodiments, the portions of the first engaging teeth and the second engaging teeth have a fan-shaped shape, wherein the fan-shaped angles of the first engaging teeth and the second engaging teeth are 60 degrees.

[0033] In some embodiments, a stepped hole is located at one end of the coupling and polished rod connection away from the gear transmission for connection to the rotary shaft.

[0034] In some embodiments, the positioning cylinder is rigidly connected to the coupling connection via a first connecting block, and the positioning rod is rigidly connected to the polished rod connection via a second connecting block.

[0035] In some embodiments, the wall of the positioning cylinder has an open groove that extends along the direction of the generatrix and through which the second connecting block passes.

[0036] In some embodiments, a device for measuring the working surface of a drilling tool comprises a pulse generator comprising a first housing, a coded disk and a valve block, wherein the first housing is part of an outer cylinder.

[0037] In some embodiments, the inner wall of the outer cylinder has several mounting grooves located in the circumferential direction and extending in the axial direction, and the coded disk has several mounting teeth that mutually correspond to said mounting grooves, wherein the coded disk is secured inside the outer cylinder by inserting said mounting teeth into said mounting grooves.

[0038] In some embodiments, the outer cylinder additionally has a keyed sleeve and a locking ring inside, the outer wall of the keyed sleeve has several mounting teeth that mutually correspond to the specified several mounting grooves, one end of the coded disk rests against the end of the mounting groove, the other end of the coded disk rests against the keyed sleeve, the locking ring is located at one end of the keyed sleeve away from the coded disk with a stop, while the locking ring is rigidly connected to the outer cylinder.

[0039] In some embodiments, a wear-resistant column is coaxially located on the end of the coded disk, and a wear-resistant groove is located on the axis of rotation of the valve block for mating rotation with the wear-resistant column.

[0040] In some embodiments, the valve block connects the gravity-type orientation sensor through the gravity valve stem and the valve stem coupling, wherein the gravity valve stem is configured to move in the axial direction relative to the valve stem coupling, and an elastic element is installed between the gravity valve stem and the valve stem coupling.

[0041] In some embodiments, the valve block is rigidly connected to the gravity valve stem, wherein one end of the valve stem coupling adjacent to the gravity valve stem has a stepped opening with a first section and a second section, wherein the second section of the opening is located inside the first section of the opening, and the cross-sectional size of the first section of the opening is larger than the cross-sectional size of the second section of the opening, wherein the first section of the opening is connected to the gravity valve stem by means of a flat key, and the elastic element includes a spring located in the second section of the opening, wherein both ends of the spring abut, respectively, against the gravity valve stem and the valve stem coupling.

[0042] In some embodiments, one end of the valve stem coupling remote from the gravity valve stem has a square hole for connecting to a gravity-type orientation sensor, and the valve stem coupling has a threaded hole extending in the radial direction and intersecting with the square hole.

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

[0044] In some embodiments, the gravity-type orientation sensor comprises a second housing, a mandrel assembly coaxially and rotatably located in the second housing and configured in such a way that the center of gravity does not coincide with the axis of rotation and there is an annular space between the mandrel assembly and the second housing, and a bearing seat assembly located in the second housing, wherein the bearing seat assembly is located at both ends of the mandrel assembly, wherein the bearing seat assembly has a first flow hole extending radially.

[0045] In some embodiments, the bearing seat assembly has a stepped bore inside for installing the bearing, wherein one open end of the stepped bore faces the mandrel assembly.

[0046] In some embodiments, both ends of the mandrel assembly have a sealing plate that engages the bearing seat assembly to seal the stepped bore of the bearing seat assembly, thereby protecting the bearing in that assembly.

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

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

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

[0050] In some embodiments, a retaining ring is rigidly mounted at one end of the bearing seat assembly away from the mandrel assembly, and the retaining ring is rigidly connected to the second housing.

[0051] In some embodiments, a second flow hole is located on the retaining ring, corresponding to the first flow hole and radially passing through the retaining ring.

[0052] In some embodiments, the second flow hole is fan-shaped, and the 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 the upper end of the mandrel assembly has an internal spherical roller bearing, and the bearing seat assembly at the lower end of the mandrel assembly has an internal radial bearing and a thrust bearing.

[0054] In another aspect of the present invention, a method is provided for measuring the inclination angle of a drilling tool using a device for measuring the inclination angle of the working surface of a drilling tool, made in accordance with any of the embodiments described above. The method includes the following steps: connecting the device for measuring the inclination angle of the working surface of a drilling tool to a set of drilling tools and calibrating a directional curve sub of the set of drilling tools with the device for measuring the inclination angle of the working surface of a drilling tool, and then lowering into the well; pumping for circulation and maintaining a stable working volume at a constant set value; driving the drilling tool by one revolution so that the coded disk rotates by one revolution relative to the valve block to obtain a pressure pulse signal;collecting and analyzing a pressure pulse signal, determining the angle between the lower side of the borehole inclination and the reference plane of the drilling tool in order to perform a measurement of the current angle of the working surface of the tool; further rotating the rotating drilling tool during one revolution and performing a re-check of the measurements; and rotating the drilling tool to rotate the working surface of the tool to a predetermined position in accordance with the measurement result.

[0055] In some embodiments, the method for measuring the working surface of a drilling tool further includes the following steps: calculating the pressure pulse and the design parameters of the coded disk according to the diaphragm flow theory; calculating the eccentric moment, bearing friction and friction of the coded disk of the gravity-type orientation sensor for different shapes, lengths and materials; modeling the dynamic response of the gravity-type orientation sensor and modeling the pressure pulse waveform to select the optimal coding of the coded disk.

[0056] Compared with the prior art, the advantages of the present invention are as follows.

[0057] The present invention uses a purely mechanical structure to replace a measurement-while-drilling tool for measuring the working surface of a tool using an electronic element in the prior art, so that the temperature it can withstand is much higher than that of the known measurement-while-drilling tool using an electronic element, so as to overcome the problem that the measurement-while-drilling tool in the related art cannot work normally under high temperature conditions.

[0058] A coded disk constructed in accordance with the present invention rotates with the drill bit. Multiple coded holes are arranged around the circumference of the coded disk, and a valve block overlapping the coded holes always faces the downhole inclination under the action of a gravity-type orientation sensor. This allows the valve block to rotate relative to the coded holes and generate various pressure pulses. The pressure pulse can be used to judge the inclination angle of the tool's working surface, allowing for correction of the drilling direction. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0060] Fig. 1 is a schematic view of a device for measuring the working surface of a drilling tool, made in accordance with some embodiments of the present invention;

[0061] Fig. 2 is a schematic view of a pulse generator constructed in accordance with some embodiments of the present invention;

[0062] Fig. 3a is a schematic view of an encoded disc constructed in accordance with some embodiments of the present invention;

[0063] Fig. 3b is a schematic view of an encoded disc constructed in accordance with some embodiments of the present invention;

[0064] Fig. 3c is a schematic view of an encoded disc constructed in accordance with some embodiments of the present invention;

[0065] Fig. 4a is a schematic front view of a valve block structure constructed in accordance with some embodiments of the present invention;

[0066] Fig. 4b is a schematic left view of a valve block structure constructed in accordance with some embodiments of the present invention;

[0067] Fig. 4c is a schematic left view of a valve block structure constructed in accordance with other embodiments of the present invention;

[0068] Fig. 5 is a schematic structural view of a first housing constructed in accordance with some embodiments of the present invention;

[0069] Fig. 6 is a schematic sectional view of a keyway bushing constructed in accordance with some embodiments of the present invention;

[0070] Fig. 7 is a schematic view of a gravity valve stem constructed in accordance with some embodiments of the present invention;

[0071] Fig. 8 is a schematic view of a valve stem connection constructed in accordance with some embodiments of the present invention;

[0072] Fig. 9 is a schematic view of the internal structure of a gravity-type attitude sensor constructed in accordance with some embodiments of the present invention;

[0073] Fig. 10 is a schematic view of a rotary shaft and a clamping unit of a gravity-type orientation sensor constructed in accordance with some embodiments of the present invention;

[0074] Fig. 11 is a schematic view of a rotary shaft and a clamping unit of a gravity-type orientation sensor constructed in accordance with other embodiments of the present invention;

[0075] Fig. 12a is a schematic sectional view of an eccentric weight block constructed in accordance with some embodiments of the present invention;

[0076] Fig. 12b is a schematic view of an end surface of an eccentric weight block constructed in accordance with some embodiments of the present invention;

[0077] Fig. 13 is a schematic view of a gravity-type orientation sensor constructed in accordance with some embodiments of the present invention;

[0078] Fig. 14a is a schematic side view of a cover plate constructed in accordance with some embodiments of the present invention;

[0079] Fig. 14b is a schematic sectional view of an eccentric weight block constructed in accordance with some embodiments of the present invention;

[0080] Fig. 15a is a schematic sectional view of a protective shell constructed in accordance with some embodiments of the present invention;

[0081] Fig. 15b is a schematic side view of a protective shell constructed in accordance with some embodiments of the present invention;

[0082] Fig. 16 is a schematic view of a connecting structure between the rotary shaft and the second housing, made in accordance with some embodiments of the present invention;

[0083] Fig. 17a is a schematic view of the end surface of a first bearing seat constructed in accordance with some embodiments of the present invention;

[0084] Fig. 17b is a schematic cross-sectional view of a first bearing seat constructed in accordance with some embodiments of the present invention;

[0085] Fig. 18a is a schematic view of the end surface of a retaining ring made in accordance with some embodiments of the present invention;

[0086] Fig. 18b is a schematic cross-sectional view of a retaining ring structure constructed in accordance with some embodiments of the present invention;

[0087] Fig. 19a is a schematic view of the end surface of a second bearing seat constructed in accordance with some embodiments of the present invention;

[0088] Fig. 19b is a schematic sectional view of a second bearing seat structure constructed in accordance with some embodiments of the present invention;

[0089] Fig. 20a is a schematic view of a three-dimensional structure of a sealing plate constructed in accordance with some embodiments of the present invention;

[0090] Fig. 20b is a schematic sectional view of a sealing plate structure constructed in accordance with some embodiments of the present invention;

[0091] Fig. 21a is a schematic view of an end surface of a sealing cover plate constructed in accordance with some embodiments of the present invention;

[0092] Fig. 21b is a schematic sectional view of a sealing cover plate structure constructed in accordance with some embodiments of the present invention;

[0093] Fig. 22 is a schematic view of a mandrel connector constructed in accordance with some embodiments of the present invention;

[0094] Fig. 23a is a schematic perspective view of a coupling joint and a positioning cylinder constructed in accordance with some embodiments of the present invention;

[0095] Fig. 23b is a schematic sectional view of a coupling structure and a positioning cylinder constructed in accordance with some embodiments of the present invention;

[0096] Fig. 24a is a schematic perspective view of the connection of a polished rod and a positioning rod constructed in accordance with some embodiments of the present invention;

[0097] Fig. 24b is a schematic cross-sectional view of the connection structures of the polished rod and the positioning rod, made in accordance with some embodiments of the present invention;

[0098] Fig. 25 is a schematic structural view of a positioning cylinder constructed in accordance with some embodiments of the present invention;

[0099] Fig. 26 is a schematic structural view of a positioning rod formed in accordance with some embodiments of the present invention;

[00100] Fig. 27a is a schematic view of an end surface of a fairing formed in accordance with some embodiments of the present invention;

[00101] Fig. 27b is a schematic sectional view of a fairing structure formed in accordance with some embodiments of the present invention;

[00102] Fig. 28 is a schematic view of a pressure pulse signal, according to one of some embodiments of the present invention;

[00103] Fig. 29 is a schematic structural view of a coded aperture formed in accordance with some embodiments of the present invention.

[00104] In the drawings: 10. outer cylinder; 1. pulse generator; 11. coded disk; 111. coded aperture; 112. first projection; 113. first installation tooth; 12.valve block; 121. cylindrical joint; 122. fan-shaped locking part; 123. pin joint; 13. key bushing; 131. second mounting tooth; 14. retaining ring; 15. wear-resistant column; 16. wear-resistant groove; 17. gravity valve stem; 171. first flat key; 172. connecting groove; 173. first keyway; 18. valve stem coupling; 181. first square hole; 182. first stepped hole; 1821. first large-diameter section; 1822. first small-diameter section; 1823. second keyway; 183. first threaded hole; 19. spring; 101. first housing; 1011. mounting groove; 2. gravity-type orientation sensor; 21. rotary shaft; 211. first through hole; 22. eccentric weight block; 221. clamping groove; 222. first half-cylinder; 223. second half-cylinder; 23. clamping block; 231. first screw; 24. cover plate; 241. second screw; 243. first mounting hole; 244. third mountinghole; 245. second large diameter section; 246. second small diameter section; 25. second projection; 26. second flat key; 27. bearing seat unit; 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. retaining ring; 281. second flow hole; 29. ​​protective shell; 291. second mounting hole; 292. dowel pin; 293. annular blind cover plate; 102. second housing; 3. mandrel connector; 31. coupling joint; 311. first engaging tooth; 312. first square hole; 313. first round hole; 32. polished rod connection; 321. second engaging tooth; 33. positioning cylinder; 331. open groove;332. first connecting block; 34. positioning rod; 341. second connecting block; 35. gear transmission; 4. upper connector; 5. fairing; 6. drill bit; 61. centralizer; 71. sealing plate; 711. third sealing ring; 72. sealing cover plate; 100. device for measuring the working surface of the drilling tool; 200. mandrel unit; 200'. mandrel unit.

[00105] In this application, all the attached drawings, which are schematic accompanying drawings, are used only to illustrate the principles of the invention and are not to scale. DETAILED DESCRIPTION

[00106] The present invention is presented below based on the accompanying drawings.

[00107] It should be noted that in this application, the direction approaching the wellhead of the present invention after descent into the well is described as “up”, “top” or similar terms, i.e. the right side of Fig. 1, while the direction away from the wellhead is described as “down”, “bottom” orsimilar terms, that is, the left side of Fig. 1. They are not used to define the absolute positions of the parts involved, but may vary depending on specific conditions.

[00108] Fig. 1 shows the structure of a device 100 for measuring the working surface of a drilling tool made in accordance with an embodiment of the present invention. As shown in Fig. 1, in order to clearly show the general structure of the device 100 for measuring the working surface of a drilling tool, this device 100 in Fig. 1 is divided into upper and lower parts, and the connection between the upper and lower parts is shown in Fig. 1 by an arrow along the center line. 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 close to the wellhead.

[00109] Fig. 2 is a schematic view of a pulse generator made in accordance with some embodiments of the presentinventions. As shown in Figs. 1 and 2, in one aspect of an embodiment of the present invention, a device 100 for measuring the working surface of a drilling tool is presented. The device 100, mounted above a drill bit, comprises an outer cylinder 10, a coded disk 11, a valve block 12 and a gravity-type orientation sensor 2. The outer cylinder 10 rotates synchronously with the drill bit, the coded disk 11 is located coaxially and rigidly inside the outer cylinder 10, and several coded holes 111 of different sizes are uniformly distributed around the circumference of the coded disk 11. The valve block 12 is located coaxially with the disk 11 with the possibility of rotation, wherein the valve block 12 is configured to at least partially cover at least one coded hole 111 during rotation, but leaves at least another coded hole 111 free. The center of gravity of the sensor 2 does not coincide with the axis of rotation of the valve block 12, thereforeblock 12 under the action of gravity always faces in one direction.

[00110] In some embodiments of the present invention, the device 100 includes a pulse generator 1 and a gravity-type orientation sensor 2 connected in series. In this embodiment, the pulse generator 1 is located coaxially above the drill bit (not shown in Fig. 1), and the sensor 2 is located coaxially above the pulse generator 1. The sensor 2 and the pulse generator 1 interact with each other during rotation of the drill bit to generate a pulse signal.

[00111] In particular, 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 rigidly located inside the first housing 101, wherein the disk 11 has a plurality of evenly spaced coded holes 111 of different sizes extending in the circumferential direction, that is, the coded disk 11 has a plurality of codedopenings 111 axially passing through the disc 11 and distributed in the circumferential direction, and the valve block 12 is coaxially and rotatably connected to the coded disc 11, wherein the valve block 12 is configured to at least partially cover at least one coded opening 111 during rotation, but at least another coded opening 111 remains free. That is, the valve block 12 can rotate coaxially relative to the disc 11 and open and close different openings 111 among the openings 111 in different rotation positions relative to the coded disc 11.

[00112] As shown in Fig. 2, in some embodiments, the first body 101 has a cylindrical shape, and it is easy to understand that the first body 101 is part of the outer cylinder 10 of the device 100. The upper and lower ends of the first body 101 have, respectively, internal and external threads, so that the lower end of the first body 101 is connected to the centralizer 61 of the outerthread, and the drill bit 6 is rigidly fixed to the lower end of the centralizer 61. The specific designs of the drill bit 6 and the centralizer 61 are known and are not described in detail here. With this method of connection, the first housing 101 of the pulse generator 1 can rotate together with the drill bit 6 during operation.

[00113] As shown in Figs. 1 and 2, in some embodiments, the coded disk 11 is coaxially and rigidly located inside the first housing 101, and the coded holes 111 of different sizes are uniformly distributed on the disk 11 in the circumferential direction, and the holes 111 pass through the disk 11, that is, the holes 111 are located at equal angular intervals on the disk 11 in the circumferential direction, and the cross-sectional sizes of the coded holes are different. The coded disk 11 is provided with a valve block 12, located coaxially and with the possibility of rotation, which is capable of at least partially overlapping the coded ones during the process of rotation relative to the disk 11openings 111 and maintain at least one coded opening 111 in an unclosed state. Due to this design, during the process of bypassing the disk 11 by the drilling fluid, the valve block 12 rotates relative to the disk 11, changing the size of the diameter of the disk 11 in such a way that the drilling fluid generates different pulse signals.

[00114] To ensure the rotation of the valve block 12 relative to the coded disk 11, in some embodiments, the valve block 12 is rigidly connected to a gravity-type orientation sensor 2, that is, the sensor 2 is rotatably mounted in the outer cylinder 10 and connected to the valve block 12. The center of gravity of the sensor 2 does not coincide with the axis of rotation of the valve block 12. Thus, under the action of gravity, the center of gravity of the sensor 2 always faces the lower side of the wellbore inclination, that is, the sensor 2 can drive the valve block 12 to synchronously rotate around the axis of rotation of the valve block 12, so that the sensor 2 canto drive the valve block 12 to rotate synchronously around the axis of rotation of the block 12, so that the block 12 maintains its orientation relative to its axis of rotation under the action of gravity. With this design, during the rotation of the disk 11 together with the drill bit, the coded holes 111 of different sizes can interact with the flowing drilling fluid, generating pulse oscillations with alternate locking of the block 12. In accordance with the present invention, when the pulse oscillations change, the hole 111 corresponding to the pulse shape causing the change in the signal shape is simply rotated in the direction smaller than the zenith angle of the wellbore, which makes it possible to determine the current angle of inclination of the working surface of the tool by analyzing the pulse wave. In addition, the pulse generator 1, made in accordance with the invention, can also reduce friction and resistance during the drilling process.

[00115] In some related fields of technology, the disk 11 is fixed in the outercylinder 10 with screws, and the drill bit 6 may generate strong vibration during the working process, so that it is likely that the disk 11 located near the drill bit 6 will not behave stably, and the local connection method with screws is prone to causing stress concentration, which increases the risk that the disk 11 will deform or weaken, which will affect the reliability of the detection result.

[00116] In some embodiments of the present invention, the inner wall of the outer cylinder 10 comprises a plurality of mounting grooves arranged in the circumferential direction and extending in the axial direction, wherein the coded disk 11 has a plurality of mounting teeth that mutually correspond to said mounting grooves, wherein the coded disk 11 is fixed inside the outer cylinder 10 by inserting said mounting teeth into said mounting grooves. One end of the coded disk 11 may abut against the end of the mounting groove 1011by means of the mounting teeth 113. In this way, the disk 11 can be securely fixed in the outer cylinder 10 so that it can maintain its mounting position relative to the outer cylinder 10 even in the case of strong vibration.

[00117] In some embodiments of the present invention, as shown in Fig. 2 and 5, three mounting grooves 1011 arranged axially are uniformly distributed in the circumferential direction along the inner wall of the first housing 101. The lower end of the mounting groove 1011 (one end adjacent to the drill bit 6) is closed, and the upper end is open.

[00118] As shown in Fig. 2, 3a, 3b and 3c, in some embodiments, the coded disk 11 is made in the form of a solid cylinder, and its outer diameter coincides with the inner diameter of the first housing 101. The three first mounting teeth 113 are uniformly distributed along the circumference of the edge of the disk 11. The cross-sectional shape of the first mounting tooth 113 corresponds to the shape of the mounting groove 1011. The codedThe disk 11 can be slidably mounted in the mounting groove 1011 of the first housing 101 by means of the first mounting teeth 113 so as to be mounted in the first housing 101 from top to bottom in the axial direction.

[00119] Inside the first housing 101, a keyway sleeve 13 and a retaining ring 14 are coaxially arranged. As shown in Fig. 6, in some embodiments, the keyway sleeve 13 has a cylindrical shape, and the outer diameter of the cylindrical shape coincides with the inner diameter of the first housing 101. The outer wall of the sleeve 13 has several mounting teeth that mutually correspond to the mounting grooves. As shown in Fig. 6, three second mounting teeth 131 are uniformly arranged on the outer cylindrical surface of the sleeve 13 in the circumferential direction, and the cross-sectional shape of the second mounting teeth 131 corresponds to the cross-sectional shape of the mounting groove 1011. As described above, the coded disk 11 is installed in the first housing 101from top to bottom in the axial direction until the first mounting teeth 113 of the coded disk 11 rest against the lower end surface of the mounting groove 1011, at which point the coded disk 11 is installed in place. Then the sleeve 13 is installed in the first housing 101 from top to bottom in the axial direction until the lower end surface of the sleeve 13 rests against the upper end surface of the disk 11, at which point the sleeve 13 is installed in place. Finally, a retaining ring 14 is installed on the upper part of the sleeve 13. As shown in Fig. 2, the contact ends of the ring 14 and the sleeve 13 are made in the form of two-step cylindrical steps matched with each other.

[00120] It is easy to understand that, although in the embodiments shown there are three mounting grooves 1011, three first mounting teeth 113 and three second mounting teeth 131, the number of mounting grooves 1011, first mounting teeth 113 and second mounting teeth 131 can be selectedby a person skilled in the art in accordance with real conditions. All these changes are within the scope of the invention.

[00121] In some embodiments, the internal thread at the upper end of the first body 101 is made conical, expanding upward. Such a design, on the one hand, ensures ease of installation of the coded disk 11, the keyway sleeve 13 and the locking ring 14. On the other hand, after the threaded connection with the first body 101, the upper downhole tool can rest against the ring 14 in the axial direction, ensuring axial fixation of the disk 11 by the sleeve 13.

[00122] In accordance with the present invention, as shown in Fig. 2, 3a, 3b and 3c, in some embodiments, to facilitate the processing of the contact surface for mating with the valve block 12, at one end of the coded disk 11, a first projection 112 is coaxially located, protruding outward, for contact with the valve block 12, and the coded holes 111 are uniformly located in positionfirst projection 112 in the circumferential direction. Coaxially on one side of the disk 11 near the valve block 12, a wear-resistant column 15 is arranged for coaxial and rotary interaction with the valve block 12. In particular, the wear-resistant column 15 in this embodiment is a PDC composite sheet embedded in the first projection 112 of the coded disk 11 for interaction with the valve block 12, which reduces wear and reduces the coefficient of friction during relative rotation, providing smoother interaction. The wear-resistant column 15 in this embodiment is not limited to a PDC composite sheet, and other wear-resistant and lubricating materials can be used.

[00123] The coded disc 11 and the valve block 12 are constantly wearing out during operation, and the PDC composite sheet installed between the coded disc 11 and the valve block 12 may also wear out, so the disc 11, the valve block 12 and the PDC composite sheet require replacement or technicalmaintenance. Thus, the integrated fastening structure of the coded disk 11, realized by means of the locking ring 14 and the key sleeve 13, provides more convenient installation and removal of the disk 11, the valve block 12 and the PDC composite sheet. Moreover, the function of positioning the coded disk 11 by the locking ring 14 and the key sleeve 13 in the axial direction is combined with the function of positioning the mounting teeth of the disk 11 and the mounting groove 1011 on the inner wall of the first housing 101 in the circumferential and radial directions, due to which the coded disk 11 and the first housing 101 are more stably and securely fixed in the circumferential, axial and radial directions, which contributes to obtaining a more accurate measurement result by the device for measuring the working surface of the drilling tool. As shown in Fig. 4a, 4b and 4c, in some embodiments, the valve block 12 has a cylindrical connection 121 of a cylindrical shape and a fan-shapedA fan-shaped locking portion 122. The circumferential center of the cylindrical connection 121 coincides with the circumferential center of the fan-shaped locking portion. Among them, a wear-resistant groove 16 for rotary connection with the wear-resistant column 15 is located on the central axis of the cylindrical connection 121. Thanks to this design, the valve block 12 can be installed together with the wear-resistant column 15 through the wear-resistant groove 16, forming a rotary pair. In this case, after connecting the valve block 12 with the wear-resistant column 15 through the wear-resistant groove 16, the end surface of the valve block 12 is in frictional contact with the first protrusion 112 of the coded disk 11. In particular, the radius of the fan-shaped blocking part 122 of the valve block 12 is equal to the radius of the first protrusion 112. The accuracy of processing the contact surface between the fan-shaped blocking part 122 and the first protrusion 112 is controlled in such a way that they both rotate relative to each other, whileThe fan-shaped locking portion 122 can lock the coded hole 111.

[00124] In this embodiment, the fan-shaped locking portion 122 simultaneously locks one at most coded hole 111. In particular, in the case where there are n coded holes 111, the 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 fan-shaped angle of the locking portion 122 is equal to the fan-shaped angle N of the coded hole 111.

[00125] In some embodiments, the number of coded holes 111 is six, the internal 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, i.e. 4N degrees. To ensure that each coded hole 111 has different dimensions with the same fan-shaped angleN, the present invention provides three different embodiments shown in Fig. 3a, 3b and 3c. In the embodiments shown in Fig. 3a and 3b, the coded openings 111 have an elliptical shape of different sizes, and in the embodiment shown in Fig. 3c, the coded openings 111 have a circular shape of different sizes, wherein, for the same fan-shaped angle, the closer the openings 111 are located to the center of the circumference of the coded disk 11, the smaller their size. Therefore, the distance between these openings 111 and the center of the circumference of the coded disk 11 is adjusted in such a way that the fan-shaped angles of the openings 111 of different sizes occupying the disk 11 are equal.

[00126] It is easy to understand that, although in the presented embodiments there are six coded holes 111, the fan-shaped angle of the valve block 12 is equal to the angle of one coded hole 111, and the number of holes 111 and the fan-shaped angle of the valve block 12 can be selected by a person skilled in the art.

[00127] In this embodiment, the coded holes 111 are coded according to the law of 1, 2 and 3 in ascending sequence, so that the coded holes 111 on the entire coded disk 11 are coded as "3, 2, 1, 3, 1, 2" and fed back to the signal receiving software, and the resulting pressure fluctuation curve is shown in Fig. 28.

[00128] According to the present invention, in some embodiments, the pulse generator 1 further comprises a gravity valve stem 17 and a valve stem coupling 18. As shown in Fig. 4b and 4c, in some embodiments, the pin connection 123 is coaxially and rigidly located on one side of the cylindrical connection 121 of the valve block 12, away from the coded disk 11. In this case, as shown in Fig. 7, in some embodiments, the lower end of the stem 17 of the gravity valve hasa connecting groove 172 for rigidly connecting with the pin connection 123. Among them, Fig. 4b and 4c show two different embodiments of the pin connection 123. In the embodiment shown in Fig. 4b, the pin connection 123 has a cylindrical shape. In this embodiment, the pin connection 123 is rigidly connected to the stem 17 of the gravity valve by means of an interference fit. In the embodiment shown in Fig. 4c, the pin connection 123 has a conical shape. In this embodiment, the pin connection 123 is rigidly connected to the stem 17 of the gravity valve by means of a pin. The upper end of the stem 17 of the gravity valve has a first keyway 173.

[00129] As shown in Fig. 8, in some embodiments, the lower end of the connecting sleeve 18 of the valve stem has a first stepped hole 182, wherein the first stepped hole 182 is designed as a secondary stepped hole. The first section 1821 of large diameterEnglish: the first stepped hole 182 is located outside the first small diameter section 1822, and the first large diameter section 1821 of the first stepped hole 182 has a second keyway 1823. As shown in Fig. 2, the first large diameter section 1821 of the first stepped hole 182 is connected to the upper end of the gravity valve stem 17 by means of a first flat key 171, and the first flat key 171 is installed in the first keyway 173 and the second keyway 1823 in such a way that when transmitting torque, they can both move in the axial direction relative to each other within a certain range. The first small diameter section 1822 of the first stepped hole 182 has a spring 19 inside, both ends of which abut, respectively, against the gravity valve stem 17 and the connecting sleeve 18 of the valve stem.

[00130] In other words, the valve stem coupling 18 has a stepped hole which is located at one endthe connecting sleeve 18 of the valve stem, but is not necessarily adjacent to the stem 17 of the gravity valve. The stepped opening has a first section and a second section, wherein the second section of the opening is located inside the first section, and the transverse dimension of the first section of the opening is larger than the second section of the opening. The first section of the opening is connected to the stem 17 of the gravity valve by means of a flat key, and the section with a larger diameter of the stepped opening is located outside and is connected to the stem 17 of the gravity valve by means of a plug. The elastic element is a spring 19 located in the second section of the opening, both ends of which rest, respectively, against the stem 17 of the gravity valve and the connecting sleeve 18 of the valve stem, that is, the spring 19 is located in the section with a smaller diameter of the stepped opening, wherein both ends of the spring 19 rest, respectively, against the stem 17 of the gravity valve and the connecting sleeve 18 of the valve stem. In comparison with

[00131] A first square hole 181 is located at the position of the central axis at the upper end of the valve stem coupling 18, and a square rotary shaft 21 is located at the corresponding end of the first square hole 181, so that both are connected to each other to transmit torque. To transmit torque, the first square hole 181 can be axially connected to the sensor 2. The upper end of the valve stem coupling 18 has a first threaded hole 183 in the radial direction, intersecting with the first square hole 181. A through hole can be located on the square part of the rotary shaft 21.a screw hole, wherein the position of the valve stem coupling 18 corresponds to the first square hole 181, for passing in the radial direction. After the square portion of the rotary shaft 21 is inserted into the first square hole 181, a screw can also be installed for passing in the radial direction so that a bolt (not shown) passes through the first threaded hole 183, and the bolt passes through the connecting element of the sensor 2, which ensures a stronger connection between them.

[00132] Due to the presence of the gravity valve stem 17 and the valve stem coupling 18, the valve block 12 is connected to the gravity-type orientation sensor 2, and at the same time, the spring 19 is located between the gravity valve stem 17 and the valve stem coupling 18 so as to create a certain downward force on the valve block 12, so that the valve block 12 is preloaded and is in closecontact with the first protrusion 112 of the coded disk 11. That is, the valve block 12 and the gravity-type orientation sensor 2 are connected via the gravity valve stem 17 and the valve stem coupling 18, wherein the gravity valve stem 17 can move relative to the valve stem coupling 18 in the axial direction, while the spring 19 is not limited to a coaxial arrangement between the gravity valve stem 17 and the valve stem coupling 18.

[00133] As shown in Fig. 9 and 16, in some embodiments, the gravity-type orientation sensor 2 is equipped with a mandrel assembly 200 containing a rotary shaft 21 and an eccentric weight block 22 rigidly fixed to the rotary shaft 21. In this case, the eccentric weight block shifts the center of gravity of the mandrel assembly 200 from the axis of rotation of the rotary shaft 21. The sensor 2 contains a second housing 102 in the form of a hollow sleeve, and the mandrel assembly 200 is mounted with the possibility of rotation inside the second housing 102 usingbearing seat assembly 27 located at both ends. In addition to being used as a drilling measurement tool in this embodiment, the mandrel assembly 200 in this embodiment can also serve as a stable platform requiring stabilization of the center of gravity, such as a rotary drilling rig and a vertical drilling tool.

[00134] As shown in FIG. 9 and 16, in some embodiments, the sensor 2 has a mandrel assembly 200' that contains a rotary shaft 21, a protective shell 29 and an eccentric weight block 22, wherein the protective shell 29 is coaxially placed on the rotary shaft 21, and the eccentric weight block 22 is rigidly mounted on the rotary shaft 21. The eccentric weight block 22 is located between the rotary shaft 21 and the protective shell 29, wherein the eccentric weight block 22 allows the center of gravity of the mandrel assembly 200 to deviate from the axis of rotation of the rotary shaft 21. The gravity-type orientation sensor 2comprises a second housing 102 in the form of a hollow sleeve, and a mandrel assembly 200 is rotatably mounted in the second housing 102 by a bearing seat assembly 27 located at both ends. In this embodiment, the mandrel assembly 200 has a purely mechanical structure to achieve the effect of stabilizing the imbalance. In addition to being used as a drilling measurement tool in this embodiment, the mandrel assembly 200 in this embodiment can also serve as a stable platform requiring stabilization of the center of gravity, such as in a rotary drilling rig and a vertical drilling tool.

[00135] According to the present invention, the structure of the gravity-type orientation sensor 2 is shown in Fig. 9. In some embodiments, the sensor 2 mainly comprises a rotary shaft 21 coaxially and rotatably located in an outer cylinder 10, and an eccentric weight block 22 rigidly fixed to the rotary shaft 21.In particular, as shown in Fig. 12a and Fig. 12b, the eccentric weight block 22 comprises two half-cylinders of the same volume, enclosing the rotary shaft 21, one of which is made of a first material and the other of a second material, wherein the density of the second material is greater than the density of the first material. That is, the eccentric weight block 22 comprises first and second half-cylinders 222 and 223 of the same volume, wherein the first and second half-cylinders 222 and 223 enclose the rotary shaft 21, forming a rigid connecting structure. One of the eccentric weight blocks 22 is made of a low-density and low-weight material, for example, plastic and a light alloy. The other eccentric weight block 22 is made of a high-density and high-weight material, for example, a high-density alloy or a lead bar. In this embodiment, the two eccentric weight blocks 22 have the same volume, but are made of materials of different densities, so that the center of gravitythe entire structure formed by the two eccentric weight blocks 22 does not coincide with its centroid. In other words, after the eccentric weight block 22 is rigidly connected to the rotary shaft 21, the center of gravity of the entire structure can deviate from the axis of rotation of the rotary shaft 21, so that the gravity-oriented part of this whole is directed under the action of gravity towards the lower side of the inclination of the wellbore.

[00136] In some embodiments, the outer wall of the rotary shaft 21 has a clamping block 23 located axially and protruding outward, so that the clamping block 23 is rigidly connected to the rotary shaft by means of a bolted connection, including, but not limited to, a rigid connection to the rotary shaft 21 by means of a first screw 231. In addition, an integral assembly method can be used, in which the clamping block 23 and the rotary shaft 21 represent a single structure, which facilitates mechanical processing by casting. That is, the clamping block 23 is rigidlyconnected to the rotary shaft 21 by means of a bolted connection or forming as a single unit.

[00137] The inner wall of the eccentric weight block 22 has a clamping groove 221 for clamping with the clamping block 23. When two eccentric weight blocks 22 surround the rotary shaft 21, the clamping groove 221 of the eccentric weight block 22 is clamped by the clamping block 23, so that the eccentric weight blocks 22 cannot move relative to the rotary shaft 21 in a circumferential or axial direction.

[00138] In the present description, two designs of the clamping block 23 are presented. As shown in Fig. 10, in some embodiments, the clamping block 23 has a multi-segment configuration. In this embodiment, the clamping block 23 consists of three parts, including, among other things, three parts of the same length, uniformly located in the axial direction on the outer wall of the rotary shaft 21, that is, located at intervals in the axial direction. As shown in Fig. 11, the clampingThe block 23 can also be arranged as a solid part in the form of a strip located on the outer wall of the rotary shaft 21 in the axial direction, that is, the clamping block is arranged in the form of a strip in the direction of the continuation of the generatrix of the rotary shaft 21. In these two arrangements, the outer wall of the rotary shaft 21 has a countersunk groove of a recessed shape that corresponds to the shape of the clamping block 23, so that the clamping block 23 is mounted on the rotary shaft 21 with a limitation and secured with the first screw 231. In particular, the first screw 231 is a countersunk head screw in order 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, there are two eccentric weight blocks 22, each of which corresponds to one clamping block 23.

[00139] In some embodiments, in order to avoid stress concentration, the clamping block 23 can be made of a cylindrical shape (not shown in the drawing). Accordingly,a recessed countersunk groove on the rotary shaft 21 for installing the clamping block 23 is formed in the shape of an arc corresponding to the shape of the clamping block 23. In this case, the clamping groove 221 on the inner side of the eccentric weight block 22 is also formed in the shape of an arc corresponding to the shape of the clamping block 23.

[00140] According to the present invention, a cover plate 24 is installed at both ends of the eccentric weight block 22, so that the outer end of the cover plate 24 projects in an axial direction in the direction of the eccentric weight block 22. As shown in Fig. 9 and 10, in some embodiments, a second projection 25 is located coaxially in a corresponding position of the rotary shaft 21 where the cover plate 24 is installed, that is, the second projection 25 is located at both ends of the rotary shaft 21 corresponding to the eccentric weight block 22. The second projection 25 can, on the one hand, axially install the block 22 of eccentric weights, and on the other hand, providea mounting base for mounting the cover plate 24.

[00141] In particular, the cover plate 24 has an annular shape and is coaxially mounted on the second projection 25 by means of a clearance fit. In this case, the cover plate 24 and the second projection 25 are connected by a second flat key 26, wherein the cover plate 24 and the eccentric weight block 22 are rigidly connected by screws passing axially (not shown in the drawing). A keyway for mounting the second flat key 26 is located on one side of the cover plate 24 and the second projection 25 adjacent to the eccentric weight block 22. After installing the cover plate 24 on the second projection 25 by means of the second flat key 26, one axial end of the second flat key 26 rests against the cover plate 24 and the second projection 25, and the other end rests against the eccentric weight block 22, thereby preventing the second flat key 26 from exiting the keyway. As shown in Fig. 10, the keyway for installing the second flatThe keys 26 and the clamping block 23 are located in the same direction of the generatrix of the rotary shaft 21. In this field of technology, it is necessary that the eccentric weight block, the projection and the cover plate interact with each other to ensure fixation without disengagement, which places high demands on the accuracy of the mating of the eccentric weight block, the projection and the cover plate. In some embodiments, the second projection 25 prevents axial movement of the eccentric weight block 22, and the cover plate 24 is rigidly connected to the eccentric weight block 22 so that they interact with each other without disengagement, which can reduce the accuracy of processing and assembly.

[00142] In some embodiments, the axial thickness of the cover plate 24 is less than the thickness of the second projection 25. In particular, the cover plate 24 is connected to the second projection 25 by means of a second flat key 26, and after the cover plate 24 is rigidly connected to the block 22eccentric weights by screws arranged in the axial direction, one axial end of the cover plate 24 is flush with one end of the second protrusion 25 and abuts against the eccentric weight block 22. Since the axial thickness of the cover plate 24 is smaller than the thickness of the second protrusion 25, the other axial end of the cover plate 24 is within the axial thickness of the second protrusion 25. With this structure, when the gravity type orientation sensor 2 is connected to other parts, it is possible to avoid the cover plate 24 from touching and being pressed against other parts, generating friction that affects the imbalance effect. In one specific embodiment, the distance from one side of the cover plate 24 from the eccentric weight block 22 to one side of the second protrusion 25 from the eccentric weight block 22 is 0.5~3 mm.

[00143] As shown in Fig. 9, in some embodiments, the edge of the cover plate 24 reaches one side of the block 22eccentric weights, and at the same time, a step is located on the end edge of the eccentric weight block 22, which corresponds to the projection of the cover plate 24. With this arrangement, the cover plate 24 can radially limit the eccentric weight block 22. As shown in Fig. 13, 14a and 14b, where the edge of the cover plate 24 reaches one side of the eccentric weight block 22, the cover plate 24 comprises a second 245 section of large diameter and a second section 246 of small diameter, wherein the section where the cover plate 24 interacts with the second projection 25 is the second section 246 of small diameter, and the section where the cover plate 24 radially rests against the eccentric weight block 22 is the second section 245 of large diameter. Six first mounting holes 243, which are located on the same radius, are distributed along the wall of the covering plate 24, corresponding to the second section 246 of small diameter in the circumferential direction, wherein the innerthe 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 has a second screw 241 on the inside, by means of which the cover plate 24 is rigidly connected to the eccentric weight block 22.

[00144] As shown in Fig. 14a, in some embodiments, three third mounting holes 244 are uniformly located in the circumferential direction on the wall of the plate corresponding to the small diameter section of the cover plate 24, and the angle between two adjacent third mounting holes 244 is 120 degrees, and the angle between the third mounting hole 244 and the first mounting hole 243 closest to it is 30 degrees. In case of using a multi-section unbalance device, the three third mounting holes 244 are used to connect other parts to the gravity-oriented device. Specifically

[00145] It is easy to understand that, although in the illustrated embodiments there are six first mounting holes 243 and three third mounting holes 244, the number of first mounting holes 243 and third mounting holes 244 can be selected by a person skilled in the art in accordance with actual conditions. All these changes are within the scope of the present invention.

[00146] The outer side at the border of the second large diameter section 245 and the second small diameter section 246 of the cover plate 24 is rounded to reduce fluid resistance and facilitate the flow of drilling fluid through the sensor 2.

[00147] In some embodiments, a protective shell 29 is also installed on the outer side of the eccentric weight block 22, as shown in Fig. 9. The protective shell 29 is a thin cylindrical shell, and both ends of the protective shell 29 in the axial direction rest against the edge sections of the two coveringplates 24, passing along one side of the block 22 of eccentric weights. The protective shell 29 prevents abrasion and wear of the block 22 of eccentric weights by solid particles in the wall of the well or circulating drilling mud during underground work, thereby extending the service life.

[00148] As shown in Fig. 9, in some embodiments, between the protective shell 29 and the second body 102 there is an annular space that ensures circulation of the drilling mud. The outer side of the border of the second section 245 of large diameter and the second section 246 of small diameter of the covering plate 24 is made rounded, which reduces fluid resistance and facilitates its passage through the sensor 2.

[00149] As shown in Fig. 15a and 15b, in some embodiments, the protective shell 29 has two semi-cylindrical structures with annular blind ends 293. The annular blind end 293 has three evenly spaced axial second mounting holes 291 for interaction withwith a mounting pin 292, that is, the inner angle between two adjacent second mounting holes 291 is 60 degrees. As shown in Fig. 13, the mounting pin 292 can pass through the second mounting hole 291 and enter the eccentric weight block 22. The wall of the large diameter section of the cover plate 24 axially abuts the annular blind end 293, preventing the pin 292 from being disconnected.

[00150] According to the present invention, the distances from the two second projections 25 to the end of the rotary shaft 21 are designated in Fig. 9 as L1 and L2, respectively. In this embodiment, the length L1 is longer than the length L2. It is easy to understand that the lengths L1 and L2 can be set according to actual needs. In addition, the lengths L1 and L2 can be set according to the type of well equipment connected to both ends of the rotary shaft 21.

[00151] As shown in Fig. 1, 9 and 10, in some embodiments, the upper and lower endsThe rotary shaft 21 is made square, and the sensor 2 is connected to the pulse generator 1 to jointly form part of the device 100 for measuring the working surface of a drilling tool. During operation, torque transmission is required between the sensor 2 and the pulse generator 1. Therefore, the upper and lower ends of the rotary shaft 21 in this embodiment are made square, which allows torque to be transmitted after their connection.

[00152] In some embodiments, as shown in Fig. 10, the lower end of the rotary shaft 21 is made square, and the cross-sectional shape of the square corresponds to the shape of the first square hole 181 in the upper end of the coupling 18 of the valve stem of the pulse generator 1 of the present invention, interacting with the first threaded hole 183, forming a through hole through which a bolt passes. Thanks to this design, the lower end of the rotary shaft 21 can be inserted into the upper end of the coupling 18valve stem, so that they both are connected to each other for transmitting torque. During operation, under the action of gravity generated by the sensor 2, one gravity-oriented side of the two eccentric weight blocks 22 is always directed towards the lower side of the wellbore inclination, and the rotary shaft 21 is fixed with the valve block 12 in the circumferential direction through the connecting sleeve 18 of the valve stem and the stem 17 of the gravity valve. Due to this design, when the coded disk 11 rotates together with the outer cylinder 10, the rigid connection of the valve block 12 with the sensor 2 in the circumferential direction makes it possible for the valve block 12 to rotate relative to the coded disk 11 in the circumferential direction, which ensures sequential interaction of the valve block 12 with the coded holes 111 of different sizes to generate regular pulses.

[00153] In some embodiments, the square end of the rotary shaft 21 is additionallyhas a first through hole 211 located in the radial direction. After the square end of the rotary shaft 21 is inserted into the first square hole 181 of the valve stem coupling 18, the central axis of the first through hole 211 coincides with the axis of the first threaded hole 183 located radially on the valve stem coupling 18, wherein the rotary shaft 21 and the valve stem coupling 18 can be fixed in the axial direction by means of a threaded connection.

[00154] According to the present invention, as shown in Fig. 16, in some embodiments, the sensor 2 further comprises a second housing 102, and the rotary shaft 21 is mounted in the second housing 102 with the possibility of rotation by means of a bearing connection. It is easy to understand that the second housing 102 is part of the outer cylinder 10 of the device 100 for measuring the working surface of a drilling tool. As shown in Fig. 1, when connecting the pulse generator 1 to the sensor2 the first housing 101 of the pulse generator 1 and the second housing 102 of the sensor 2 are connected to each other by means of a screw connection, so that the first housing 101 and the second housing 102 together form part of the outer cylinder 10 of the device 100 for measuring the working surface of a drilling tool.

[00155] In some embodiments, the bearing seat assembly 27 is coaxially and rigidly located inside the second housing 102. In particular, the bearing seat assembly 27 comprises a first bearing seat 2701 and a second bearing seat 2702 for connection, respectively, to the upper and lower ends of the rotary shaft 21.

[00156] In Fig. 17a and 17b show the design of the first bearing seat 2701 located on the upper end of the rotary shaft 21. In some embodiments, the bearing seat assembly 27 has an internal stepped hole for installing the bearing, wherein one open end of the stepped hole faces the mandrel assembly 200.The bearing seat assembly 27 at the upper end of the mandrel assembly 200 is equipped with a spherical roller bearing, and the bearing seat assembly 27 at the lower end of the mandrel assembly 200 is equipped with a radial bearing and a thrust bearing. A stepped hole is located along the central axis of the first bearing seat 2701, wherein the part with a small diameter of the stepped hole is intended for installation on the rotary shaft 21, and the part with a large diameter of the stepped hole is the first part 2703 of the bearing mount for installing the bearing. In this embodiment, a spherical roller bearing of model No. 22206 is installed in the first part 2703 of the bearing mount.

[00157] The mating surface of the sealing plate 71 and the bearing seat assembly 27 has sealing rings that are designed with the possibility of coaxial rotation and a hermetically sealed connection with each other. That is, the mating surface of the sealing plate 71 and the seat unit 27The bearing has a sealing ring that is configured to rotate coaxially and be sealed. The first sealing ring 2704 is coaxially secured to the end face of the first bearing seat 2701 facing the cover plate 24, wherein the size of the first sealing ring 2704 is larger than the size of the first bearing seat 2703. The sealing plate 71 is coaxially secured to the end face of the cover plate 24 facing the first bearing seat 2701, wherein the sealing plate 71 interacts with the bearing seat assembly 27, sealing the stepped opening of the bearing seat assembly 27, protecting the bearing in this assembly. As shown in Fig. 20a and 20b, the sealing plate 71 is formed as a single ring, and three countersunk holes, evenly spaced along the edges of the sealing plate 71 along the circumference, correspond to the three third mounting holes 244 of the cover plate 24, so thatThe sealing plate 71 and the cover plates 24 are rigidly and hermetically connected by a bolted connection. The mating surface of the sealing plate 71 and the bearing seat assembly 27 has sealing rings that are configured to rotate coaxially and are hermetically connected to each other, wherein the size of the sealing ring is larger than the size of the stepped hole of the bearing seat assembly. A third sealing ring 711 is coaxially fixed to the end of the sealing plate 71 facing the first bearing seat 2701, wherein the third sealing ring 711 and the first sealing ring 2704 of the first bearing seat 2701 are in a dynamic sealing connection that ensures their sleeve connection with each other. Due to this arrangement, the bearing in the first seat 2701 is sealed and protected, preventing liquid from entering it.

[00158] At the same time, the first flow holes 271 are evenly distributed in the circumferentialin the direction of the first bearing seat 2701 with the ability to pass through the first bearing seat 2701, as a flow channel for drilling fluid. The first flow holes 271 are located along the periphery of the first sealing ring 2704, that is, the size of the circle surrounded by the first flow holes 271 is larger than that of the first sealing ring 2704, which prevents drilling fluid from entering the first flow holes 271 into the first sealing ring 2704. In this embodiment, the first bearing seat 2701 has three first flow holes 271, and the internal angle between adjacent first flow holes 271 is 120 degrees. The first flow hole 271 is fan-shaped, wherein both ends of the first flow hole 271 along the circumference have a semicircular shape, and the internal angle between the centers of the semicircles at both ends of the first flow hole 271 is N2 degrees.

[00159] Fig. 19a and 19b show the structure of the second bearing seat 2702 located on the lower end of the rotary shaft 21. In some embodiments, the structure of the second bearing seat 2702 is similar to the structure of the first bearing seat 2701, except that the mounting portion 2705 of the second bearing seat 2702 is a stepped hole, the small diameter portion of which is used to install the radial bearing 274 with the model number NJ206E, and the large diameter portion of which is used to install 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.

[00160] Similar to the design of the first bearing seat 2701, the second sealing ring 2706 is coaxially secured to the end of the second bearing seat 2702 facing the cover plate 24, and the size of the secondsealing ring 2706 is larger than the size of the mounting portion 2705 of the second bearing. Similarly, the cover plate 24 adjacent to the second bearing seat 2702 is also rigidly sealed by the sealing plate 71, so that the third sealing ring 711 and the second sealing ring 2706 of the sealing plate 71 are in a dynamic sealing connection, so that they form a sleeve connection with each other, thereby sealing the bearing in the second bearing seat 2702.

[00161] As shown in Fig. 16, in some embodiments, a retaining ring 273 is additionally provided between the thrust bearing 272 and the radial bearing 274.

[00162] According to the present invention, as shown in Fig. 16, in some embodiments, the inner wall at the lower end of the second housing 102 has a step, and after the rotary shaft 21 is installed on the second housing 102, the lower end of the second bearing seat 2702abuts against a 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 on the lower end of the rotary shaft 21. The sealing plate 71 on 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 locking ring 28 is rigidly located at one end of the bearing seat assembly 27 away from the mandrel assembly 200, and the locking ring 28 is rigidly connected to the second housing 102. In this embodiment, the locking ring 28 is rigidly mounted on the upper end of the first bearing seat 2701, and the cylindrical side surface of the locking ring 28 is rigidly connected to the inner wall of the second housing 102.

[00163] The design of the retaining ring 28 is shown in Fig. 18a and 18b. In some embodiments, the retaining ring 28 has a second flow hole 281,corresponding to the first flow hole 271 passing radially through the retaining ring 28, wherein the size of the second flow hole 281 is larger than that of the first flow hole 271. Here, the dimensions may 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 fan-shaped, and the fan-shaped angle of the second flow hole 281 is larger than that of the first flow hole 271. The retaining ring 28 has second flow holes 281 uniformly spaced in the circumferential direction, wherein 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 the shape of the first flow hole 271, but the difference is that the internal angle between the centers of the semicircles at both axial ends of the second flow hole 281 isN1 degrees, where N1> N2. For example, in this embodiment, the internal angle between the centers of the semicircles at both ends of the circumference of the first flow hole 271 is 60 degrees, and the internal angle between the centers of the semicircles at both ends of the circumference of the second flow hole 281 is 70 degrees. By setting the ratio of the sizes between the first flow hole 271 and the second flow hole 281, it is possible to achieve a gradual change in the flow rate along the direction of the fluid flow, which will reduce losses caused by an abrupt change in flow rate.

[00164] The retaining ring 28 has an internal stepped hole. With this arrangement, the edge of the retaining ring 28 is thicker than the intermediate portion, and the second flow hole 281 is located on the thin portion of the retaining ring 28. In this case, the thin portion of the retaining ring 28 is used to secure the fairing 5. The specific design of the fairing 5 is shown below. The flat end of the retaining ring 28comes into contact with the first bearing seat 2701, and the retaining ring 28 is fixed on the first bearing seat 2701 with four M4 screws evenly spaced around the circumference such that the four screws are located on the inner side of the circumference surrounded by the second through-hole 281.

[00165] In addition to creating the effect of fixing the first bearing seat 2701, the retaining ring 28 can also form a dynamic sealing connection with the rotary shaft 21, thereby further enhancing the sealing protection of the bearing in the first bearing seat 2701.

[00166] 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 does not need to be fixed with the retaining ring 28 like the first bearing seat 2701. In one particular embodiment, the sealing cover plate 72 is rigidly sealed on the end of the secondbearing seat 2702 away from the eccentric weight block 22. The structure of the sealing cover plate 72 is shown in Fig. 21a and 21b, and the sealing cover plate 72 is made integrally annular and is hermetically and coaxially put on the rotary shaft 21. In this case, the sealing cover plate 72 is rigidly connected to the second bearing seat 2702 by means of four M4 screws equally spaced along the circumference. As shown in Fig. 16, the diameter of the sealing cover plate 72 is smaller than the diameter of the circle surrounded by the first flow holes 271. Therefore, after the sealing cover plate 72 is rigidly connected to the second bearing seat 2702, the sealing cover plate 72 cannot block the first flow hole 271 of the second bearing seat 2702.

[00167] In accordance with the present invention, it is possible to sequentially use several orientation sensors 2gravity type. When used sequentially, the line connecting the centers of gravity of several gravity-type orientation sensors 2 is parallel to 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 several sensors 2 is parallel to the axes of rotation of said several sensors 2, and the heavier blocks 22 of the eccentric weights are located on one side, which makes it possible to superimpose the effect of the imbalance of several sensors 2, thereby enhancing the effect of the gravitational effect. Said several sensors 2 can be connected via the mandrel connector 3.

[00168] Fig. 22 shows the design of the mandrel connector 3 made in accordance with the present invention. In some embodiments, the mandrel connector 3 serves as part of the device 100 for detecting the working surface of a drilling tool for connecting the sensors 2. The mandrel connector 3 comprises a sleeve connection 31 and a polished connection 32rods connected to each other in a cylindrical shape, wherein the positioning cylinder 33 is rigidly fixed to the outer wall of the coupling joint 31 in the axial direction, and the positioning rod 34 is rigidly fixed to the outer wall of the polished rod joint 32 in the axial direction. In this case, when the coupling joint 31 is connected to the polished rod joint 32, the positioning rod 34 and the positioning cylinder 33 are connected to each other by means of a gear transmission 35 located on their end surfaces. The positioning rod 34 and the positioning cylinder 33 are connected to each other jointly to ensure directional positioning. The coupling joint 31 and the polished rod joint 32 are connected to each other to transmit torque.

[00169] In some embodiments, as shown in Fig. 23a and 23b, the first engaging teeth 311 are evenly spaced at one end of the coupling 31 along the circumference, forminggear transmission 35 of coupling connection 31. In this embodiment, there are three first engaging teeth 311, wherein the cross-section of one first engaging tooth 311 has a fan-shaped form. The angle of the fan-shaped cross-section of one first engaging tooth 311 is 60 degrees, and the gap angle between two adjacent first engaging teeth 311 is also 60 degrees.

[00170] At the other end of coupling connection 31, a stepped hole is made. The section of the stepped hole closest to the first engaging teeth 311 has a small diameter and is a first square hole 312, made in the shape of a square, which can be plugged by a square structure at the end of rotary shaft 21 for transmitting torque. The large diameter section of the stepped hole inside the coupling joint 31 is a first circular hole 313 made in the form of a cylinder, which can be plugged with a cylindrical structure onend of rotary shaft 21. In this case, first circular hole 313 is a circumscribed circle of first square hole 312.

[00171] Positioning cylinder 33 has a cylindrical shape, and its wall has an open groove 331 extending along the generatrix. That is, the cylinder wall of positioning cylinder 33 has an open groove 331 through which the second connecting block 341 passes along the generatrix. The generatrix on which the open groove 331 is located, the central axis of positioning cylinder 33 and the central axis of coupling connection 31 are in the same plane, and open groove 331 serves for passage of second connecting block 341. The position in which positioning cylinder 33 is rigidly connected to coupling connection 31 corresponds to the gap between two adjacent first engaging teeth 311.

[00172] As shown in Fig. 24a and Fig. 24b, in some embodiments, at intervals at one end of the polished rod connection 32 in the circumferential directionseveral second engaging teeth 321 are uniformly arranged, since the gear transmission 35 of the connection 32 of the polished rod, that is, the gear transmission 35 for the conjugate engagement, is located at one end, where the coupling connection 31 and the connection 32 of the polished rod are connected to each other. The gear transmission 35 comprises several first engaging teeth 311, located on the end surface of the coupling connection 31 in the circumferential direction, and several second engaging teeth 321, located on the end surface of the connection 32 of the polished rod in the circumferential direction, that is, the said several first engaging teeth 311 are uniformly arranged on the end surface of the coupling connection 31 in the circumferential direction, and the second engaging teeth 321 are uniformly arranged on the end surface of the connection 32 of the polished rod in the circumferential direction. In particular, since the function of the second engaging teeth 321 is to engage with the first engaging teethteeth 311 and the transmission of torque, the shape of the second engaging teeth 321 corresponds to the shape of the gap between two adjacent first engaging teeth 311. In this embodiment, since the first engaging teeth 311 and the gap between them have the same shape, there are also three second engaging teeth 321 with the same shape as the first engaging teeth 311, which are also made fan-shaped, and the fan-shaped angle of the second engaging teeth 321 is 60 degrees, that is, the fan-shaped angle of the second engaging teeth 321 is 60 degrees.

[00173] At one end of the coupling connection 31 and the connection 32 of the polished rod, away from the gear transmission 35, a stepped hole is made for connection with the rotary shaft 21, wherein the large diameter section of the stepped hole has a circular shape corresponding to the rotary shaft 21, and the small diameter section of the stepped hole has a square shape corresponding to the rotary shaft 21, wherein the roundthe hole is a circle described around a square hole. The shape of the stepped hole is similar to the shape of the stepped hole inside the coupling joint 31, which is not described in detail here.

[00174] The positioning rod 34 has a cylindrical shape, and one end thereof, intended for installation in the positioning cylinder 33, has a hemispherical shape, which is convenient for installation. The connection point of the positioning rod 34 with the connection 32 of the polished rod is located on the second engaging teeth 321. Due to this design, after the positioning rod 34 is installed in the positioning cylinder 33, the first engaging teeth 311 accurately engage with the second engaging teeth 321.

[00175] As shown in Fig. 22, in some embodiments, after the coupling connection 31 is plugged with the polished rod connection 32, one end of the positioning cylinder 33, located near the polished rod connection 32, extends beyondlimits of the length range of this connection 32 in its direction. One end of the positioning rod 34, located near the coupling connection 31, protrudes in the direction of the coupling connection 31, but the end of the positioning rod 34 is still within the length range of the coupling connection 31.

[00176] According to Figs. 25 and 26, in some embodiments, the positioning cylinder 33 is rigidly connected to the coupling connection 31 by means of a first connecting block 332. In particular, the positioning cylinder 33 is rigidly connected to the first connecting block 332 by welding, and the first connecting block 332 is rigidly connected to the coupling connection 31 by welding.

[00177] The positioning rod 34 is rigidly connected to the connection 32 of the polished rod by means of the second connecting block 341. In particular, the positioning rod 34 is rigidly connected to the second connecting block 341 by welding, and the second connecting block 341 is rigidly connected to the connection 32polished rod by welding. The cross-sectional shape of the second connecting block 341 corresponds to the shape of the open groove 331 on the positioning cylinder 33.

[00178] As shown in Fig. 1, in some embodiments, after several gravity-type orientation sensors 2 are connected in series, an upper connector 4 is located at the upper end of the second body 102 of the sensor 2. The upper connector 4 is designed as a conventional drill joint that uses conventional threaded connections of drilling tools or special threaded connections for screw drilling tools used in the prior art and mainly provides for connecting a combination of drilling tools. In this case, the upper end of the sensor 2 has a fairing 5 connected by a screw connection. The specific design of the fairing 5 is shown in Figs. 27a and 27b. In some embodiments, the fairing 5 has a generally cylindrical shape, and at one end thereofa flange is located for a rigid connection with the retaining ring 28 of the sensor 2. The threaded hole in the flange is made with a countersink and corresponds to the threaded hole in the retaining ring 28 and the threaded hole in the first seat 2701 of the bearing.

[00179] The diameter of the flange of the fairing 5 is less than or equal to the diameter of the thin part of the retaining ring 28. In one preferred embodiment, the diameter of the flange of the fairing 5 is equal to the diameter of the thin part of the retaining ring 28. Thus, after installing the fairing 5 on the retaining ring 28, the flange of the fairing 5 can be inserted into the retaining ring 28, which allows for quick assembly of the structure and increases its stability.

[00180] Inside one of the ends of the fairing 5, where the flange is located, there is a cylindrical blind hole with one end for accommodating the rotary shaft 21, and the length and diameter of the cylindrical blind hole are greater than the corresponding size of the rotary shaft 21 in order to leave enough space forinstallation.

[00181] One of the ends of the fairing 5, remote from the flange, is made in the shape of a sphere. Between the upper connector 4 and the fairing 5, an annular flow channel is formed, which mainly provides a direction for the flow of drilling mud. The spherical shape at the end of the fairing 5 contributes to a more efficient flow of drilling mud.

[00182] In another aspect of the present invention, a measuring method is provided using a device 100 for measuring the working surface of a drilling tool. The method includes the following steps:

[00183] connecting the device for measuring the working surface of a drilling tool to a drilling tool assembly and calibrating the directional curve sub of the drilling tool assembly with the device for measuring the working surface of a drilling tool, and then lowering it into the well;

[00184] pumping for circulation and maintaining a stable working volume at a constant certain value, that is, maintaining a stableworking volume at a constant predetermined value;

[00185] driving the drilling tool to rotate by one revolution so that the coded disk rotates by one revolution relative to the valve block to obtain a pressure pulse signal, that is, generating regular pressure pulse signals, and collecting and analyzing the pressure pulse signal, estimating the angle between the lower side of the borehole inclination and the reference plane of the drilling tool, so as to realize the measurement of the current angle of the working surface of the tool;

[00186] further forcibly rotating the drilling tool by one revolution, that is, rotating the drilling tool clockwise by another revolution, and performing a recheck of the measurements;

[00187] correctly rotating the drilling tool to force the working surface of the tool to rotate to a predetermined position in accordance with the measurement result.

[00188] In other embodiments, the measuring method usingThe device 100 further includes the following steps:

[00189] designing the coded hole 111 on the coded disk 11 in accordance with the diaphragm flow theory, that is, designing the pressure pulse and the design parameters of the coded disk 11 in accordance with the diaphragm flow theory.

[00190] The torque of the sensor 2, the frictional resistance of each bearing and the frictional resistance of the coded disk 11 are calculated to form a theoretical calculation system for the drive torque and the frictional moment, that is, calculating the eccentric torque, the frictional resistance of the bearing and the frictional resistance of the coded disk of the gravity-type orientation sensor under different shapes, different lengths and different materials.

[00191] The device for measuring the working surface of the drilling tool is simulated using the simulation software, and the rationality of the theoretical calculations is checked in steps S6-S8, that is,modeling the dynamic response of the gravity-type orientation sensor and modeling the pressure pulse shape to select the optimal encoding of the coded disk.

[00192] Specific steps of the method for measuring the angle of a drilling tool using a device for measuring the working surface of a drilling tool in some embodiments are given below:

[00193] 1) According to the theory of flow through an orifice, the design of pressure pulses and the design parameters of the coded disk 11 in the pulse generator 1 are completed, and theoretical calculations of the waveform parameters are obtained to form a set of coded measurement methods,

[00194] where the empirical formula of the flow through an orifice is shown as follows:

[00195] in the formula:ΔP: pressure difference between both sides of the hole, bar;ρ: density of the fluid, g / cm 3 ;q: flow rate through the orifice, l / min;C d: flow coefficient;d: flow orifice diameter, mm.

[00196] From the formula it can be seen that the pressure difference ΔP between both sides of the orifice and the flow rate q, the diameter d of the flow orifice, the density ρ of the fluid and the coefficient C d flow are directly related, with the pressure difference ΔP between both sides of the orifice and the flow rate q and density ρ of the fluid being defined quantities, and the flow coefficient Cd is usually determined experimentally, and only reference values ​​are provided when used. In the case where the fluid flow is fully compressed (1>7d), when the Reynolds coefficient Re≤10 5 , C d =0.964*Re -0,05 When Re>10 5 , C d can be considered a constant value with a value satisfying condition C d=0.6~0.62. When the fluid flow is not fully compressed, its flow coefficient satisfies the condition of Cd≈0.7~0.8.

[00197] Based on the empirical formula of the flow through the orifice, the initial design solution of the disk 11 can be realized by determining the initial design size of each coded orifice 111.

[00198] 2) Depending on the material, shape and length of the sensor 2, its torque is calculated, and the calculation of the frictional resistance of each bearing and the frictional resistance of the coded disk is supplemented by a theoretical system for calculating the torque and frictional moment. This part of the theoretical calculation is the prior art, and the calculations can be performed by referring to Physics Terminology (2nd edition) of China Science Publishing House.

[00199] 3) The dynamic response of the eccentric weight block 22 and the pressure pulse shape of the pulse generator 1 are simulated using commercial simulation software such as ADAMS and ANSYS to check the rationality of the theoretical calculation.

[00200] 4) For processing and assembling the entire set of equipment, as well as connecting the set of drilling tools, it is preferable to use optimal coding.

[00201] 5) After completing the calibration of the directional curved sub (not shown in the drawing) using the device 100, the drilling tool is lowered into a directional or horizontal well. For calibrating the directional curved sub using the device 100, reference may be made to the process of calibrating an existing directional curved sub using an existing measuring device.

[00202] 6) Pumping is performed for circulation and a stable working volume is maintained at a constant certain value.

[00203] 7) The rotary table (not shown in the drawing) is rotated clockwise by the wellhead operation, and the device 100 is rotated by one revolution, wherein the prior art is the driving of the rotary table, which will not be described in detail here.

[00204] 8) Since the valve block 12 is always stabilized on the lower side of the wellbore inclination, and the first body 101 of the pulse generator 1 drives the coded disk 11 in the circumferential direction, this causes the valve block 12 to rotate relative to the coded disk 11. The valve block 12 sequentially closes various coded openings 111 of the coded disk 11. In the case of a constant flow rate, a change in the throttling area can lead to a change in the pressure in the equipment, forming a regular pulse pressure signal. As shown in Fig.28 and 29, depending on the aperture of the coded hole 111, they are coded as 1, 2 and 3 in ascending sequence. If one coded disk 11 is coded as 321312, the size of the coded hole 111 sequentially corresponds to the size "large, medium, small, large, small and medium". When the coded disk 11 is rotated, the valve block 12 sequentially closes six coded holes 111: "large, medium, small, large, small and medium", obtaining a pressure pulse curve with amplitudes "high, medium, low, high, low, medium", respectively. Thus, according to this rule, it is possible to estimate the value of the current angle of the front surface of the tool. The abscissa in Fig. 28 corresponds to degrees from 0 to 360 degrees on the coded disk 11 shown in Fig. 29.For a specific method for calculating the angle of the working surface of a tool, reference may be made to Patent No. CN 110374581 B entitled ULTRA-HIGH-TEMPERATURE MECHANICAL ORIENTING DEVICE FOR MEASURING THE WORKING SURFACE OF A TOOL AND A METHOD OF DESIGNING THEREOF.

[00205] 9) The pressure pulse signal is fed back to the wellhead signal acquisition and monitoring system by measuring the pressure fluctuations in the riser.

[00206] 10) The angle between the lower side of the wellbore inclination and the reference plane of the drilling tool is estimated by analyzing the waveform and phase to realize the measurement of the current angle of the working surface of the tool.

[00207] 11) The device 100 is rotated clockwise for another revolution to perform a repeat control measurement.

[00208] 12) The device 100 is rotated accordingly, causing the working surface of the instrument to move to a given position in accordance with the measurement result.

[00209] With reference to the content of the previously described embodiments, in one aspect of the present invention a pulse generator is provided. The pulse generator comprises:

[00210] a first housing;

[00211] an encoded disk coaxially and rigidly located inside the first housing, wherein on the encoded disk a plurality of encoded openings of different sizes are uniformly distributed, passing through the encoded disk in the circumferential direction;

[00212] a valve block configured to be coaxially and rotary connected to the encoded disk, wherein the valve block is configured to at least partially cover at least one encoded opening during rotation, but at the same time leaves at least another encoded opening free.

[00213] The device in this embodiment can serve as a mechanical measuring tool for directional drilling, generating a pressure pulse signal and providing its subsequent analysis of the position of the working surface of the tool, which makes it possible to eliminate the use of electronic elements and ensure the operation of the measuring tool for directional drilling in high-temperature conditions. In addition, the device can serve as a tool and equipment for reducing friction and resistance during directional drilling, and also provide vibration of pressure pulses.

[00214] In some embodiments, the valve block is connected to a gravity-type orientation sensor, wherein the center of gravity of the gravity-type orientation sensor does not coincide with the axis of rotation of the valve block, so that the valve block always faces in one direction under the action of gravity.

[00215] In some embodiments, the first housing further has a keyed sleeve and a locking 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 keyed sleeve, wherein the locking ring abuts against one end of the keyed sleeve away from the coded disk, and the locking ring is rigidly connected to the first housing.

[00216] In some embodiments, on the inner wall of the first housing in the circumferential direction, several mounting grooves are uniformly distributed, extending in the axial direction, and mounting teeth, which are in one-to-one correspondence with said mounting grooves, are located on the coded disk and the outer wall of the keyed sleeve, wherein one end of the coded disk abuts against the end of the mounting groove through the mounting tooth.

[00217] In some embodiments, a wear-resistant column is coaxially located on the end of the coded disk, and a wear-resistant groove is located on the axis of rotation of the valve block, mated with the wear-resistant column with the possibility of rotation.

[00218] In some embodiments, the valve block is connected to a gravity-type orientation sensor through a gravity valve stem and a valve stem coupling, wherein a spring is coaxially located between the gravity valve stem and the valve stem coupling.

[00219] In some embodiments, the valve block is rigidly connected to the gravity valve stem, at one end of the valve stem coupling there is a stepped hole, wherein a large diameter section of the stepped hole is located on the outer side and is connected to the gravity valve stem by means of a plug, a spring is located in a small diameter section of the stepped hole, and both ends of the spring abut, respectively, against the gravity valve stem and the valve stem coupling.

[00220] In some embodiments, one end of the valve stem coupling, remote from the gravity valve stem, has a square hole for connection to a gravity-type orientation sensor, wherein the valve stem coupling has a threaded hole extending in the radial direction so that the threaded hole intersects with the square hole.

[00221] In some embodiments, the fan-shaped angles of the coded holes are equal, and the fan-shaped angle of a coded hole of n coded holes is 360° / (2n).

[00222] In some embodiments, the valve blocks are fan-shaped, and the inclination angle of the valve block is equal to the inclination angle of the coded hole.

[00223] With reference to the content of the previously described embodiments, in one aspect of the present invention, a mandrel assembly is provided for a gravity-type orientation sensor. The mandrel assembly includes a rotary shaft, a protective shell coaxially placed on the rotary shaft, an eccentric weight block rigidly fixed on the rotary shaft, wherein the eccentric weight block is located between the rotary shaft and the protective shell and is configured to provide a deviation of the center of gravity of the mandrel assembly from the axis of rotation of the rotary shaft.

[00224] This embodiment is a mandrel assembly for a gravity-based orientation sensor for a mechanical directional drilling tool, which utilizes a purely mechanical design to achieve a stable gravity-based effect. The mandrel assembly can serve not only as a measuring instrument and drilling device, but also as a stable platform requiring stabilization of the center of gravity, such as in a rotary drilling rig and a vertical drilling tool. This design eliminates the need for an electronic element, thereby improving high-temperature resistance.

[00225] In some embodiments, an annular blind end is located on the inner side of the end of the protective shell, and the end of the eccentric weight block axially abuts against the annular blind end, and several mounting pins are uniformly arranged on the annular blind end for connection with the eccentric weight block in the circumferential direction.

[00226] In some embodiments, the rotary shaft has two coaxially arranged cover plates located, respectively, at both ends of the eccentric weight block, and the outer ends of the cover plates axially protrude toward 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, preventing the mounting pin from being disconnected.

[00227] In some embodiments, the rotary shaft has a second projection for interacting with the cover plate, and the cover plate is coaxially mounted on the second projection by means of a second flat key located near the eccentric weight block.

[00228] In some embodiments, the thickness of the cover plate is less than the thickness of the second projection.

[00229] In some embodiments, the eccentric weight block contains two semi-cylindrical shapes with the same volume that rigidly cover the outer wall of the rotary shaft, wherein one of the two semi-cylindrical eccentric weight blocks is made of a high-density material, and the other is made of a low-density material.

[00230] In some embodiments, the clamping block is rigidly connected to the outer wall of the rotary shaft, and the eccentric weight block has a clamping groove for clamping with the clamping block; each eccentric weight block corresponds to one of the clamping blocks in the form of a strip and located along the generatrix of the rotary shaft.

[00231] In some embodiments, the clamping blocks are divided into three sections of equal length and are uniformly located on the outer wall of the rotary shaft.

[00232] In some embodiments, the clamping block is rigidly connected to the rotary shaft using a bolted connection.

[00233] In some embodiments, the clamping block is rigidly connected to the rotary shaft in an integral manner.

[00234] With reference to the content of the previously described embodiments, in one aspect of the present invention, a mandrel assembly for a gravity-type orientation sensor is provided.The mandrel assembly comprises:

[00235] a rotary shaft; and

[00236] an eccentric weight block rigidly fixed to the rotary shaft, wherein the eccentric weight block allows the center of gravity of the mandrel assembly to deviate from the axis of rotation of the rotary shaft.

[00237] This embodiment provides a mandrel assembly for a gravity-based orientation sensor for a mechanical directional drilling tool that uses a purely mechanical design to achieve a stable gravity-based effect. The mandrel assembly can serve not only as a tool and a measuring device during drilling, but also as a stable platform requiring stabilization of the center of gravity, such as in a rotary drilling rig and a vertical drilling tool.

[00238] In some embodiments, the eccentric weight block contains two semi-cylindrical shapes with the same volume that rigidly embrace the outer wall of the rotary shaft, wherein one of the two semi-cylindrical eccentric weight blocks is made of a high-density material, and the other is made of a low-density material.

[00239] In some embodiments, the clamping block is rigidly connected to the outer wall of the rotary shaft, and the eccentric weight block has a clamping groove for clamping with the clamping block.

[00240] In some embodiments, each of the eccentric weight blocks corresponds to one of the clamping blocks that are strip-shaped and located along the generatrix of the rotary shaft.

[00241] In some embodiments, the clamping blocks are divided into three sections of the same length and are uniformly located on the outer wall of the rotary shaft.

[00242] In some embodiments, the clamping block is rigidly connected to the rotary shaft using a bolted connection.

[00243] In some embodiments, the clamping block is integrally connected to the rotary shaft.

[00244] In some embodiments, the rotary shaft has two coaxially arranged cover plates located at both ends of the eccentric weight block, respectively, and the outer ends of the cover plates extend axially in the direction of the eccentric weight block, so that the outer wall of the eccentric weight block radially abuts the cover plate.

[00245] In some embodiments, the rotary shaft has a second projection for interacting with the cover plate, and the cover plate is coaxially mounted on the second projection by means of a second flat key located near the eccentric weight block.

[00246] In some embodiments, the thickness of the cover plate is less than the thickness of the second projection.

[00247] With reference to the content of the embodiments described earlier, in one aspect of the invention there is a mandrel connector for connecting to the rotary shafts of two adjacent gravity-type orientation sensors, including a coupling connection and a polished rod connection, wherein at one end, where the coupling connection and the polished rod connection are connected to each other, a gear transmission for a mating connection is located, a positioning cylinder is located at the edge of the coupling connection, and a positioning rod for connecting with the positioning cylinder is located at the edge of the polished rod connection.

[00248] In this embodiment, a gravity-type orientation sensor for a mechanical directional drilling tool is proposed. It makes it possible to place and connect two purely mechanical gravity-type orientation sensors, and to transmit torque.In this case, the mandrel assembly is connected to the second housing through the bearing seat assembly, which ensures the circulation of drilling fluid in the annular space between the mandrel assembly and the second housing, while simultaneously protecting the bearing in the bearing seat assembly and providing the necessary sealing. This embodiment can serve not only as a tool and a measuring device during the drilling process, but also as a stable platform requiring stabilization of the center of gravity, for example, in a rotary drilling rig and a vertical drilling tool.

[00249] In some embodiments, the coupling connection and the polished rod connection have a cylindrical shape, and the gear transmission contains several first engaging teeth uniformly spaced on the end surface of the coupling connection, and several second engaging teeth uniformly spaced on the end surface of the polished rod connection in the circumferential direction.

[00250] In some embodiments, the shape of the gap between adjacent first engaging teeth matches the shape of the second engaging teeth.

[00251] In some embodiments, the number of first and second teeth is three.

[00252] In some embodiments, the cross-sections of the first engaging teeth and the second engaging teeth are fan-shaped, and the fan-shaped angles of the first engaging teeth and the second engaging teeth are 60 degrees.

[00253] In some embodiments, at one end of the coupling connection and the polished rod connection, away from the gear transmission, a stepped hole is located for connection with the rotary shaft.

[00254] In some embodiments, a portion of the stepped hole with a large diameter is formed as a round hole corresponding to the rotary shaft, and a portion of the stepped hole with a small diameter is formed as a square hole corresponding to the rotary shaft.

[00255] In some embodiments, the circular hole is a circumscribed circle of a square hole.

[00256] In some embodiments, the positioning cylinder is rigidly connected to the coupling connection via a first connecting block, and the positioning rod is rigidly connected to the polished rod connection via a second connecting block.

[00257] In some embodiments, the wall of the positioning cylinder has an open groove through which the second connecting block passes along the generatrix.

[00258] With reference to the content of the previously described embodiments, in one aspect of the present invention, a gravity-type orientation sensor is provided.A gravity-type orientation sensor comprises a second housing, a mandrel assembly coaxially and rotatably mounted in the second housing, wherein the mandrel assembly is designed in such a way that the center of gravity does not coincide with the axis of rotation, and between the mandrel assembly and the second housing there is an annular space; a bearing seat assembly located in the second housing, wherein the bearing seat assembly is located at both ends of the mandrel assembly, and the bearing seat assembly has a first flow hole that extends radially.

[00259] In this embodiment, a gravity-type orientation sensor is proposed for a mechanical directional drilling tool that uses a purely mechanical design to achieve a stable gravity-oriented effect.A gravity-type orientation sensor is connected to the second housing via a bearing seat assembly, which ensures circulation of drilling fluid in the annular space between the mandrel assembly and the second housing, while simultaneously protecting the bearing in the bearing seat assembly and providing the necessary sealing. This embodiment can serve not only as a tool and a measuring device during drilling, but also as a stable platform requiring stabilization of the center of gravity, for example, for a rotary drilling rig and a vertical drilling tool.

[00260] In some embodiments, the bearing seat assembly has a stepped bore inside for mounting a bearing, and one open end of the stepped bore faces the mandrel assembly.

[00261] In some embodiments, both ends of the mandrel assembly have a sealing plate that cooperates with the bearing seat assembly to seal the stepped bore of the bearing seat assembly, thereby protecting the bearing in the bearing seat assembly.

[00262] In some embodiments, a sealing ring is located on a mating surface of the sealing plate and the bearing seat assembly, coaxially rotating so as to create a seal with each other, and the size of the sealing ring is larger than the size of the stepped bore of the bearing seat assembly.

[00263] In some embodiments, the number of first flow holes is three, and they are evenly spaced on the bearing seat assembly around the circumference, and the size of the circumference surrounded by the first flow holes is larger than that of the sealing ring.

[00264] In some embodiments, the first flow hole is fan-shaped.

[00265] In some embodiments, the retaining ring is rigidly mounted on one end of the bearing seat assembly away from the mandrel assembly, and the retaining ring is rigidly connected to the second housing.

[00266] In some embodiments, a second flow hole corresponding to the first flow hole is located on the retaining ring 28 for radially passing through the retaining ring.

[00267] In some embodiments, the second flow hole is fan-shaped, and the fan-shaped angle of the second flow hole is greater than that of the first flow hole.

[00268] In some embodiments, the bearing seat assembly at the upper end of the mandrel assembly has an inner spherical roller bearing, and the bearing seat assembly at the lower end of the mandrel assembly has an inner radial bearing and a thrust bearing.

[00269] With reference to the content of the previously described embodiments, in one aspect of the present invention, a device for measuring the working surface of a drilling tool, mounted above a drill bit, is proposed.The said device comprises:

[00270] an outer cylinder configured to rotate synchronously with a drill bit;

[00271] a coded disk coaxially and rigidly located inside a first housing, wherein several coded openings of different sizes are uniformly arranged on the coded disk in a circumferential direction, passing through the coded disk;

[00272] a valve block configured to be coaxially and rotaryly connected to the coded disk, wherein the valve block is configured to at least partially cover at least one coded opening during rotation, but leaves at least another coded opening free;

[00273] a gravity-type orientation sensor connected to the valve block, wherein the center of gravity of the said sensor does not coincide with the axis of rotation of the valve block, so that the valve block always faces in one direction under the action of gravity.

[00274] The present invention utilizes a purely mechanical structure to replace a while-drilling measurement tool for measuring the working surface of the tool using an electronic element constructed in accordance with the prior art, so that its permissible temperature is significantly higher than that of a while-drilling measurement tool using an electronic element constructed in accordance with the prior art, thereby overcoming the problem of incorrect operation of the while-drilling measurement tool under high temperature conditions.Moreover, the coded disk rotates together with the drill bit, several coded holes are arranged around the circumference of the coded disk, and the valve block blocking the coded holes always faces the lower side of the borehole inclination under the action of the gravity-type orientation sensor, which allows the valve block to rotate relative to the coded holes and generate various pressure pulses. The pressure pulse can be used to determine the angle of inclination of the working surface of the tool, which allows for the correction of the drilling direction.

[00275] In some embodiments, the gravity-type orientation sensor comprises a rotary shaft connected to the valve block, and the outer wall of the rotary shaft has a block of eccentric weights, as a result of which the axis of rotation of the gravity-type orientation sensor does not coincide with the center of gravity.

[00276] In some embodiments, a device for measuring the working surface of a drilling tool comprises several gravity-type orientation sensors connected to each other via a mandrel connector, and a straight line passing through the center of gravity of said sensors is parallel to the axis of rotation of said sensors.

[00277] In some embodiments, the outer cylinder further has a keyed sleeve and a locking ring inside, several mounting grooves that are located in the axial direction and are uniformly distributed on the inner wall of the outer cylinder in the circumferential direction, wherein the coded disk and the outer wall of the keyed sleeve have several mounting teeth that mutually correspond to the mounting grooves in a one-to-one manner, wherein one end of the coded disk rests against the end of the mounting groove by means of the mounting teeth, and the other end of the coded disk rests against the keyed sleeve, the locking ring is located with the possibility of abutment on one end of the keyed sleeve away from the coded disk, and the locking ring is rigidly connected to the outer cylinder.

[00278] In some embodiments, a wear-resistant column is coaxially located on the end of the coded disk, and a wear-resistant groove is located on the axis of rotation of the valve block, mated with the wear-resistant column with the possibility of rotation.

[00279] In some embodiments, the valve block is connected to a gravity-type orientation sensor through a gravity valve stem and a valve stem coupling, wherein a spring is coaxially located between the gravity valve stem and the valve stem coupling.

[00280] In some embodiments, the valve block is rigidly connected to the gravity valve stem, a stepped hole is located at one end of the valve stem coupling, a large diameter section of the stepped hole is located on the outside and is connected to the gravity valve stem by means of a plug, a spring is located in a small diameter section of the stepped hole, and both ends of the spring abut, respectively, against the gravity valve stem and the valve stem coupling.

[00281] In some embodiments, one end of the valve stem connection remote from the gravity valve stem has a square hole for connection to a gravity-type orientation sensor, and the valve stem connection has a threaded hole extending in a radial direction so that the threaded hole intersects with the square hole.

[00282] In some embodiments, the fan-shaped angles of the coded holes are equal, and the fan-shaped angles of the 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.

[00283] In some embodiments, the eccentric weight block comprises two half-cylinders with equal volumes that enclose the rotary shaft, one of which is made of a low-density material and the other of a high-density material.

[00284] In some embodiments, the clamping block is rigidly connected to the outer wall of the rotary shaft, and the eccentric weight block has a clamping groove for clamping with the clamping block.

[00285] In some embodiments, the rotary shaft has two coaxially arranged cover plates located, respectively, at both ends of the eccentric weight block, and the outer ends of the cover plates axially extend in the direction of the eccentric weight block, so that the outer wall of the eccentric weight block radially abuts against the cover plate.

[00286] In some embodiments, the rotary shaft has a second projection for interacting with the cover plate, and the cover plate is coaxially mounted on the second projection by means of a second flat key located near the eccentric weight block.

[00287] In some embodiments, both ends of the rotary shaft are connected to the outer cylinder via a bearing, wherein the outer cylinder has a bearing seat assembly inside for mounting a bearing, wherein a plurality of first flow holes are uniformly distributed on the bearing seat assembly in a circumferential direction, so that the first flow holes are located circumferentially outside the bearing.

[00288] In some embodiments, the outer cylinder further has a retaining ring on the inside, rigidly connected to the bearing seat assembly, so that the retaining ring is located on one side of the bearing seat assembly away from the eccentric weight block, wherein a plurality of second flow holes corresponding to the first flow holes are uniformly distributed on the retaining ring in a circumferential direction, and the dimensions of the second flow holes are larger than the dimensions of the first flow holes.

[00289] In some embodiments, the bearing seat assembly has a radial bearing and a thrust bearing inside, wherein the thrust bearing is located closer to the eccentric weight block than the radial bearing, and a bearing retaining ring is located between the thrust bearing and the radial bearing.

[00290] In some embodiments, the mandrel connector includes a coupling connection and a polished rod connection, a gear transmission for mating locking is located at one end, where the coupling connection and the polished rod connection are connected to each other, a positioning cylinder is located at the edge of the coupling connection, and a positioning rod for locking with the positioning cylinder is located at the edge of the polished rod connection.

[00291] In some embodiments, the upper connector is formed at one end of the outer cylinder remote from the drill bit, and the fairing is mounted at one end of the rotary shaft remote from the drill bit, wherein one end of the fairing remote from the rotary shaft is formed in the form of a spherical surface, and a channel for drilling mud is formed between the fairing and the upper connector.

[00292] In one aspect of the present invention, a method for measuring the inclination angle of a drilling tool is provided using the previously described device for measuring the inclination angle of the working surface of a drilling tool. The method includes the following steps:

[00293] S1. Coded holes on the coded disk are designed in accordance with the diaphragm flow theory;

[00294] S2.The torque of the gravity-type orientation sensor, the frictional resistance of each bearing and the frictional resistance of the coded disk are calculated to form a theoretical system for calculating the torque and the frictional moment;

[00295] S3. The device for measuring the working surface of the drilling tool is simulated using the simulation software, and the rationality of the theoretical calculations at steps S1 and S2 is checked;

[00296] S4. The device for measuring the working surface of the drilling tool is connected to the drilling tool set, and the directional curve sub of the drilling tool set is calibrated using the device for measuring the working surface of the drilling tool to perform lowering into the well;

[00297] S5. Pumping is performed to circulate and maintain a stable working volume at a certain constant value.

[00298] S6.The drilling tool is driven to rotate by one revolution so that the coded disk rotates by one revolution relative to the valve block to obtain regular pressure pulse signals;

[00299] the pressure pulse signals are collected and analyzed, and the angle between the lower side of the borehole inclination and the reference plane of the drilling tool is estimated to realize the measurement of the current angle of the working surface of the tool;

[00300] S7. The drilling tool is rotated clockwise by another revolution to perform a repeated control measurement;

[00301] S8. The drilling tool is rotated properly so that its working surface moves to a predetermined position in accordance with the measurement result.

[00302] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and cannot be construed as indicating or implying relative importance or implicitly indicating the number of the specified technical characteristics. Accordingly, the characteristics identified as "first" and "second" may include one or more of these characteristics, explicitly or implicitly. In the description of the present invention, the term "multiple" means two or more, unless otherwise specifically stated.

[00303] In the present description, unless otherwise specified, the terms "installed," "attached to," "connected to," and "fastened" should be understood in a broad sense, such as "may be rigidly connected, removably 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 within two elements. Those skilled in the art will understand the specific meanings of the above-described terms in the present description depending on the specific circumstances.

[00304] In the present description, terms referring to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" mean that the particular features, structures, materials, or characteristics described in connection with a given embodiment or example are included in at least one embodiment or example of the present invention. In the present description, schematic expressions of the terms described above do not necessarily refer to the same embodiment or example. Moreover, the particular features, structures, materials, or characteristics may be combined in any one or more embodiments or examples as appropriate. Finally, it should be noted that the foregoing is only a preferred embodiment of the present invention and does not impose any limitations on the present invention.Although the present invention has been described in detail with reference to previously described embodiments, those skilled in the art may modify the technical solution set forth in the above-described embodiments or replace some technical characteristics with equivalent ones. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention shall be included within the scope of legal protection of the present invention.

Claims

1. A device for measuring the angle of inclination of the working surface of a drilling tool, intended for connection with a drill bit, wherein said device comprises: an outer cylinder (10) designed to rotate synchronously with the drill bit, a coded disk (11) rigidly located inside the outer cylinder (10) and having several coded holes (111) passing in the axial direction through the coded disk (11) and located in the circumferential direction, a valve block (12) configured to rotate coaxially relative to the coded disk (11) and to open and close various coded openings (111) of said coded openings (111) in different rotation positions relative to the coded disk (11), and a gravity-type orientation sensor (2) rotatably located inside the outer cylinder (10) and connected to the valve block (12), wherein the center of gravity of said sensor (2) does not coincide with the axis of rotation of the valve block (12), and the gravity-type orientation sensor (2) is configured to actuate the valve block (12) for synchronous rotation around the axis of rotation of the valve block (12), so that said sensor (2) ensures the possibility of maintaining the orientation of the valve block (12) relative to the axis of rotation of the valve block (12) under the action of gravity, wherein the inner wall of the outer cylinder (10) has several mounting grooves located along the circumferential direction and extending in the axial direction, the coded disk (11) has several mounting teeth that mutually correspond to said mounting grooves in a one-to-one manner, and the coded disk (11) is secured inside the outer cylinder (10) by inserting said mounting teeth into said mounting grooves.

2. The device according to claim 1, in which the gravity-type orientation sensor (2) comprises a rotary shaft (21) connected to a valve block (12), wherein the outer wall of the rotary shaft (21) has a block (22) of eccentric weights, due to which the axis of rotation of said sensor (2) does not coincide with its center of gravity.

3. The device according to claim 2, in which both ends of the rotary shaft (21) are connected to the outer cylinder (10) via a bearing, wherein the outer cylinder (10) has inside it a bearing seat assembly (27) for installing a bearing, wherein the bearing seat assembly (27) has several first flow holes (271) evenly spaced in the circumferential direction, so that the first flow holes (271) are located circumferentially outside the bearing.

4. The device according to claim 3, in which the outer cylinder (10) additionally has a retaining ring (28) inside, rigidly connected to the bearing seat assembly (27), wherein the retaining ring (28) is located on one side of the bearing seat assembly (27) away from the eccentric weight block (22) and has several second flow holes (281) corresponding to the first flow holes (271), wherein said second flow holes (281) are uniformly distributed in the circumferential direction and the size of their cross-section is larger than that of the first flow holes (271).

5. A device according to any one of paragraphs 2-4, in which the rotary shaft (21) has two cover plates (24) located coaxially, respectively, at both ends of the block (22) of eccentric weights, and the outer ends of the cover plates (24) axially extend in the direction of the block (22) of eccentric weights so that the outer wall of the block (22) of eccentric weights radially abuts against the cover plate (24).

6. The device according to claim 5, in which the rotary shaft (21) has a second projection (25) for interaction with the cover plate (24), wherein the cover plate (24) is coaxially placed on the second projection (25) by means of a second flat key (26) located near the block (22) of eccentric weights.

7. A device according to any one of paragraphs 2-6, in which a clamping block (23) is rigidly connected to the outer wall of the rotary shaft (21), and the block (22) of eccentric weights has a clamping groove for clamping with the clamping block (23).

8. A device according to any one of paragraphs 1-7, comprising several gravity-type orientation sensors (2), connected to each other by means of a mandrel connector (3), wherein a straight line passing through the centers of gravity of said sensors (2) is parallel to the axes of rotation of said sensors (2).

9. The device according to claim 8, in which the connector (3) of the mandrel comprises a coupling connection (31) and a connection (32) of the polished rod, and at one end, where the coupling connection (31) and the connection (32) of the polished rod are connected to each other, a gear transmission (35) for a mating connection is located, at the edge of the coupling connection (31) a positioning cylinder (33) is located, and at the edge of the connection (32) of the polished rod a positioning rod (34) is located for connection with the positioning cylinder (33).

10. The device according to claim 9, in which the coupling connection (31) and the connection (32) of the polished rod have a cylindrical shape, and the gear transmission (35) contains several first engaging teeth (311) located on the end surface of the coupling connection (31) in the circumferential direction, and second engaging teeth located on the end surface of the connection (32) of the polished rod in the circumferential direction.

11. A device according to any one of paragraphs 9, 10, in which at one end of the coupling connection (31) and the connection (32) of the polished rod at a distance from the gear transmission (35) there is a stepped hole for connection with the rotary shaft (21).

12. The device according to any one of paragraphs. 9-11, in which the positioning cylinder (33) is rigidly connected to the coupling connection (31) via the first connecting block (332), and the positioning rod (34) is rigidly connected to the polished rod (32) via the second connecting block (341).

13. The device according to claim 12, in which the cylindrical wall of the positioning cylinder (33) has an open groove (331) which runs along the direction of the generatrix and through which the second connecting block (341) passes.

14. The device according to claim 1, in which the outer cylinder (10) additionally has a keyed sleeve (13) and a locking ring (14) inside, wherein the outer wall of the keyed sleeve (13) has several mounting teeth that mutually correspond one-to-one to the said mounting grooves, and one end of the coded disk (11) rests against the end of the mounting groove, and the other end of the coded disk (11) rests against the keyed sleeve (13), wherein the locking ring (14) is located with an abutment at one end of the keyed sleeve (13) away from the coded disk (11) and is rigidly connected to the outer cylinder (10).

15. A device according to any one of paragraphs 1-14, in which a wear-resistant column (15) is coaxially located on the end of the coded disk (11), and a wear-resistant groove (16) is located on the axis of rotation of the valve block (12), intended for conjugate rotation with the wear-resistant column (15).

16. A device according to any one of paragraphs 1-15, in which the valve block (12) is connected to the gravity-type orientation sensor (2) via the gravity valve stem (17) and the valve stem coupling (18), wherein the gravity valve stem (17) is configured to move in the axial direction relative to the valve stem coupling (18), and an elastic element is located between the gravity valve stem (17) and the valve stem coupling (18).

17. The device according to claim 16, in which the valve block (12) is rigidly connected to the stem (17) of the gravity valve, one end of the connecting sleeve (18) of the valve stem, adjacent to the stem (17) of the gravity valve, has a stepped opening, having a first section and a second section, wherein the second section of the opening is located inside the first section of the opening, and the cross-sectional size of the first section of the opening is larger than that of the second section of the opening, wherein the first section of the opening is connected to the stem (17) of the gravity valve through a flat key, and the elastic element comprises a spring (19) located in the second section of the opening, wherein both ends of the spring (19) rest, respectively, against the stem (17) of the gravity valve and the connecting sleeve (18) of the valve stem.

18. A method for measuring the angle of inclination of the working surface of a drilling tool using a device for measuring the angle of inclination of the working surface of a drilling tool, which is intended for connection with a drill bit and comprises: an outer cylinder (10) designed to rotate synchronously with the drill bit, a coded disk (11) rigidly located inside the outer cylinder (10) and having several coded holes (111) passing in the axial direction through the coded disk (11) and located in the circumferential direction, a valve block (12) configured to rotate coaxially relative to the coded disk (11) and to open and close various coded openings (111) of said coded openings (111) in different rotation positions relative to the coded disk (11), and a gravity-type orientation sensor (2) rotatably located inside the outer cylinder (10) and connected to the valve block (12), wherein the center of gravity of said sensor (2) does not coincide with the axis of rotation of the valve block (12), and the gravity-type orientation sensor (2) is configured to actuate the valve block (12) for synchronous rotation around the axis of rotation of the valve block (12), so that said sensor (2) ensures the possibility of maintaining the orientation of the valve block (12) relative to the axis of rotation of the valve block (12) under the action of gravity, wherein the inner wall of the outer cylinder (10) has several mounting grooves located along the circumferential direction and extending in the axial direction, the coded disk (11) has several mounting teeth that mutually correspond to said mounting grooves in a one-to-one manner, and the coded disk (11) is secured inside the outer cylinder (10) by inserting said mounting teeth into said mounting grooves, wherein the said method includes the following steps: connecting the said device to the drilling tool complex and calibrating the directional curve sub of the drilling tool complex using the said device, and then lowering it into the well; pumping for circulation and maintaining a stable working volume at a constant set value; causing the drilling tool to rotate one revolution so that the coded disk rotates one revolution relative to the valve block to obtain a pressure pulse signal; collecting and analyzing the pressure pulse signal, estimating the angle between the bottom of the borehole inclination and the reference plane of the drilling tool in order to measure the current angle of the working surface of the tool; ensuring that the drilling tool continues to rotate one revolution and that the measurements are rechecked; and rotation of the drilling tool, ensuring rotation of the working surface of the tool to a given position in accordance with the measurement result.

19. The method according to paragraph 18, further comprising the following steps: calculation of pressure impulse and design parameters of the coded disk according to the theory of diaphragm flow; calculation of eccentric moment, bearing friction and coded disk friction of a gravity-type attitude sensor for different shapes, lengths and materials; and Modeling the dynamic response of a gravity-type orientation sensor and modeling the pressure pulse shape to select the optimal encoding of the coded disk.

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