A deep water steep slope opening device and method

Abstract

The application provides a deep water steep slope opening device and method. The deep water steep slope opening device comprises a sleeve, a truss, a sleeve holder and a floating platform, the end of the truss is provided with a through hole for the sleeve to pass through, the sleeve is arranged in the truss, the truss is hinged to the floating platform, and the sleeve is detachably provided with the sleeve holder for axially limiting the sleeve. The hinge type connection of the truss and the floating platform is established, the truss and the sleeve can be rotated along the shaft, the different angle drilling needs can be adapted, the sleeve is arranged in the truss and leans together with the truss, and the technical problems that the sleeve is bent and broken or cannot be fixed when drilling and opening the steep slope part under the deep water condition are solved.

Description

Technical Field

[0001] This invention relates to the field of drilling technology, and in particular to a device and method for drilling holes in deep water and steep slopes. Background Technology

[0002] In engineering, underwater drilling is frequently required for geological exploration or other engineering purposes. Underwater boreholes can be arranged as straight or inclined holes, depending on the needs. The current practice is to first lower a casing, then hammer the top of the casing to force the bottom into the overburden layer of a steep slope to secure it. Next, a drill string one level below the casing is inserted into the casing and lowered in for advance core drilling. After the advance reaches a certain depth (approximately 0.5m-1.0m), the drill string is pulled out, and the top of the casing is hammered again to drive the casing feet into the bottom of the hole. The drill string is then lowered a second time for core drilling, and this process is repeated until the casing feet penetrate the overburden layer. Finally, the drill string is lowered again to drill to the final hole depth.

[0003] Whether it is straight hole construction or inclined hole construction, hole opening is the basis of drilling. The hole opening must be at the predetermined elevation and position to ensure that the engineering design requirements are met.

[0004] For drilling on sloping land, whether it is a straight hole or an inclined hole, a hole slightly larger than the outer diameter of the casing can be dug on the slope manually or mechanically, and then the casing can be lowered into the hole to complete the drilling.

[0005] When drilling holes in the lower section of an underwater slope, if the hole opening is not deep from the water surface, mechanical or manual assistance can be used, such as using an underwater excavator or directly diving to dig out a hole larger than the outer diameter of the casing, and then lowering the casing into the hole to complete the drilling.

[0006] When the borehole is deep enough to be easily drilled, such as when it is located on the bank slope of a reservoir, drilling becomes extremely difficult. The steeper the slope, the greater the difficulty. Drilling cannot be completed without the ability to place the casing. If the water depth exceeds 60 meters, it becomes very difficult to complete the drilling using divers or other auxiliary methods.

[0007] In deep-water inclined hole construction, if the casing or drill bit is directly lowered to open the hole, the casing or drill bit will bend significantly or even break due to the limited rigidity of the casing or drill bit itself, making it impossible to open the hole at the predetermined position and thus preventing drilling.

[0008] In deep-water straight hole construction, if the casing or drill bit is directly lowered to open the hole, the drill bit or casing will slide down the slope under the action of gravity, making it impossible to open the hole at the predetermined elevation, and thus the drilling cannot be achieved. Summary of the Invention

[0009] The purpose of this invention is to provide a device and method for drilling holes on steep slopes in deep water, which solves the technical problem of casing bending and breaking or being unable to be fixed when drilling holes on steep slopes in deep water conditions.

[0010] The technical solution of the present invention is as follows: a deep-water steep slope drilling device includes a casing, a truss, a casing clamp and a floating platform. The end of the truss is provided with a through hole for the casing to pass through. The casing is disposed inside the truss. The truss is hinged to the floating platform. The casing clamp is detachably provided on the casing for axially limiting the casing.

[0011] In the above scheme, by establishing a hinged connection between the truss and the floating platform, the truss and casing can rotate along the axis to adapt to the drilling needs at different angles. Moreover, the casing is installed inside the truss and "lies at an angle" together with the truss, solving the technical problem of casing bending and breaking or being unable to be fixed when drilling in steep slopes under deep water conditions.

[0012] Preferably, the floating platform has a cavity open at one or both ends in the X direction, and the truss is hinged to the cavity and tilts and swings along the hinge point toward the open position of the cavity. The open cavity structure provides the maximum yaw angle for the truss to tilt.

[0013] Preferably, the deep-water steep-slope drilling device further includes a support plate, a bearing device, and a telescopic cylinder. The casing passes through the support plate, the lower end of the support plate is connected to the truss, and the upper end of the support plate is equipped with a casing clamp. The cylinder of the telescopic cylinder is connected to the support plate via the bearing device, and the telescopic rod of the telescopic cylinder is vertically connected to the floating platform. The telescopic cylinder provides compensation for the rise and fall of the truss and casing, adapting to changes in reservoir water level during drilling.

[0014] The telescopic cylinder is a hydraulic cylinder with a hydraulic lock to keep the installation height of the truss and sleeve stable and not change with water level.

[0015] Preferably, two telescopic cylinders are provided at each end of the bearing plate in the Y direction, and the cylinder barrels of the two telescopic cylinders at the same end are connected by a connecting plate; the bearing device is connected to the bearing plate and the connecting plate.

[0016] The two sets of telescopic cylinders are of the same specification and are connected by a connecting plate to ensure that the sleeve clamp can be supported and moved smoothly.

[0017] The bearing assembly includes a shaft, a bearing, and a bearing housing. A bearing housing is respectively disposed at the same end of the bearing plate and the connecting plate in the Y direction. Each bearing housing contains one bearing, and the shaft connects the two bearings. The bearing assembly has a total of two bearings, allowing for more flexible truss swing and enabling the bearing assembly to withstand larger radial loads.

[0018] Preferably, the sleeve holder includes a housing, slips, and a base. The housing has a V-shaped conical hole that is wider at the top and narrower at the bottom. Two slips are arranged opposite each other within the V-shaped conical hole. The sleeve passes between the two oppositely arranged slips. Both ends of the housing are mounted on top of the truss via the base. The slips are weight-bearing slips, arranged opposite each other within the V-shaped conical hole; the lower they fall, the more effective the clamping force.

[0019] Preferably, the floating platform includes a deck, steel beams, mounting bolts, and pontoons. The pontoons are located at both ends of the truss in the Y direction and extend along the X direction. A deck is located on the pontoons near the truss. Multiple steel beams are arranged along the X direction on the pontoons, and mounting bolts that can encircle the pontoons are provided on the steel beams. The steel beams near the truss are connected to the deck, and the steel beams away from the truss connect the pontoons at both ends in the Y direction.

[0020] Preferably, the truss includes uprights, horizontal bars, diagonal braces, flanges, foot spikes, and through holes. The uprights are arranged in a triangular pattern on the flanges, and both ends of the uprights are connected through the flanges. Each pair of uprights is connected by multiple horizontal bars, and each pair of horizontal bars is connected by diagonal braces. Multiple foot spikes are provided on the lower end face of the flange at the bottom of the truss.

[0021] The present invention also provides a method for drilling holes in deep water steep slopes, comprising:

[0022] 1) Obtain the location of the opening on the steep slope, then obtain the water depth H and borehole apex angle φ at the opening location, and calculate the horizontal distance D from the floating platform to the opening location and the vertical length L of the truss being lowered.

[0023] 2) Move the floating platform to a position at distance D and anchor it;

[0024] 3) Lower the truss at the location of the floating platform: Tie a steel wire rope to the lower part of the truss, and connect the other end of the steel wire rope to the hoist at the top of the steep slope; then assemble the remaining trusses section by section from this truss and lower them gradually until the length of the truss is equal to the vertical length L calculated in step 1), and then stop lowering the truss.

[0025] 4) Insert the casing into the truss, install a casing holder on the upper part of the casing, and lower the drill bit along the casing. The upper parts of the truss, casing and drill bit are all connected to the floating platform, and the lower parts are suspended in the water.

[0026] 5) Start the hoist and tighten the wire rope to lift the truss, so that the truss tilts relative to the floating platform in the direction of the steep slope until the truss contacts the steep slope and reaches the opening. Fix the truss on the steep slope.

[0027] 6) Start the drilling tool and complete the drilling.

[0028] This invention also provides another method for deep-water steep slope drilling, comprising:

[0029] 1) Obtain the location of the opening on the steep slope, then obtain the water depth H and borehole apex angle φ at the opening location, and calculate the horizontal distance D from the floating platform to the opening location and the vertical length L of the truss being lowered.

[0030] 2) Move the floating platform to a position at distance D and anchor it;

[0031] 3) Lower the truss at the location of the floating platform: Tie a steel wire rope to the lower part of the truss, and connect the other end of the steel wire rope to the hoist at the top of the steep slope; then assemble the remaining trusses section by section from this truss and lower them gradually until the length of the truss is equal to the vertical length L calculated in step 1), and then stop lowering the truss.

[0032] 4) Insert the sleeve into the truss, start the hoist to tighten the wire rope and lift the truss, so that the truss tilts relative to the floating platform in the direction of the steep slope until the truss contacts the steep slope and reaches the opening position, fix the truss on the steep slope; remove the sleeve clamp.

[0033] 5) Start the drill string to perform inclined drilling. After reaching a certain drilling depth, lift the drill string to drive the drill bit to grind the hole wall. Then lower the drill string and lift it again. Repeat this process several times to enlarge the hole diameter.

[0034] 6) Raise the drill bit to position it inside the casing, keep the bottom of the truss in the opening position, and move the floating platform a certain distance in the direction of the steep slope so that the truss gradually stands upright and the upper part extends out of the floating platform until the truss reaches directly above the opening position.

[0035] 7) Start the drilling tool and complete the drilling.

[0036] Whether drilling at an angle or a straight angle, the truss and casing in deep-water, steep-slope drilling methods possess heave compensation capabilities, adapting to minor water level fluctuations during drilling. When water level changes exceed the heave compensation range of the hydraulic cylinders, the truss can be adjusted by adding or removing sections to accommodate the water level changes. If the deviation between the drilling angle and the design angle is detected to be greater than the allowable deviation, the floating platform can be moved to adjust the truss angle to the design angle, providing greater flexibility.

[0037] Compared with related technologies, the beneficial effects of the present invention are as follows:

[0038] I. This invention enables safe and efficient inclined hole drilling on deep water and steep slopes, solving the problem in the prior art where the casing is easily bent or broken when drilling inclined holes on deep water and steep slopes.

[0039] II. This invention provides a method for "nesting" on steep slopes in deep water, which solves the problem in the prior art that when drilling straight holes on steep slopes in deep water, the water-proof sleeve slides down the slope and cannot take root, thus enabling straight hole drilling to be carried out smoothly on steep slopes in deep water.

[0040] Third, this invention provides a device and method for integrated heave compensation of truss and casing, which adapts to changes in reservoir water level during drilling, breaking through the current situation where only truss or casing can be compensated, making drilling safer and more efficient. Attached Figure Description

[0041] Figure 1 A schematic diagram of the deep-water steep slope opening device provided by the present invention;

[0042] Figure 2 This is a schematic diagram of the truss structure;

[0043] Figure 3 This is a schematic diagram of the bearing assembly.

[0044] Figure 4 A schematic diagram showing the installation of the bearing plate, sleeve clamp, telescopic cylinder, and bearing device, with the bearing plate and sleeve clamp in a horizontal position.

[0045] Figure 5 This is a cross-sectional schematic diagram of the outer shell and the slips in the casing clamp;

[0046] Figure 6 for Figure 4 A schematic diagram showing the bearing plate and sleeve holder in an inclined position;

[0047] Figure 7 This is a schematic diagram showing the state of the telescopic hydraulic cylinder when the water level rises.

[0048] Figure 8 This is a schematic diagram showing the state of the telescopic hydraulic cylinder when the water level drops.

[0049] Figure 9 Schematic diagram for calculating truss length and floating platform position;

[0050] Figure 10 A schematic diagram of the deep-water steep slope drilling device provided by the present invention for drilling inclined holes on a deep-water steep slope;

[0051] Figure 11 A schematic diagram of the plan layout for fixing a floating platform;

[0052] Figure 12 A schematic diagram (I) of the deep-water steep slope drilling device provided by the present invention for drilling straight holes on deep-water steep slopes;

[0053] Figure 13 A schematic diagram (II) of the deep-water steep slope drilling device provided by the present invention for drilling straight holes on deep-water steep slopes;

[0054] Figure 14 A schematic diagram (III) of the deep-water steep slope drilling device provided by the present invention for drilling straight holes on deep-water steep slopes;

[0055] In the attached diagram: 1. Casing; 2. Truss; 3. Telescopic cylinder; 4. Casing clamp; 5. Bearing assembly; 6. Support plate; 7. Floating platform; 8. Wire rope; 9. Hoist; 10. Drilling tool; 11. Winch; 12. Anchor rope; 13. Anchor pile;

[0056] 21. Upright pole; 22. Horizontal bar; 23. Diagonal brace; 24. Flange; 25. Foot nail; 26. Through hole; 31. Telescopic pole; 32. Cylinder; 33. Connecting plate; 34. Fastening bolt; 41. Outer shell; 42. Slip; 43. Base; 44. V-shaped tapered hole; 51. Shaft; 52. Bearing; 53. Bearing seat; 54. Bearing bolt; 55. Bearing nut; 61. Enclosure; 62. Cavity; 71. Deck; 72. Steel beam; 73. Mounting bolt; 74. Float box; 75. Cavity. Detailed Implementation

[0057] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. For ease of description, the terms "upper," "lower," "left," and "right" used below only indicate that they correspond to the upper, lower, left, and right directions in the accompanying drawings and do not limit the structure.

[0058] like Figure 1 As shown, the deep-water steep slope drilling device provided in this embodiment includes a casing 1, a truss 2, a telescopic cylinder 3, a casing clamp 4, a bearing device 5, a bearing plate 6, and a floating platform 7.

[0059] like Figure 1 , Figure 2 As shown, the truss 2 includes uprights 21, crossbars 22, diagonal braces 23, flanges 24, foot spikes 25, and through holes 26. The flange 24 is triangular, with triangular through holes 26 for the sleeve 1 to pass through. The uprights 21 are arranged in a triangular pattern on the flange 24, and both ends of the uprights 21 are connected through the flange 24. Thus, the truss 2 forms a triangular prism shape, which is lightweight, has high rigidity, good stability, and is not easily deformed.

[0060] The flange 24 can be designed in three specifications: first, an A flange 24 with foot spikes 25 located at the bottom of the lowest truss 2; second, a B flange 24 located at the joint of multiple trusses 2 in the middle; and third, a C flange 24 located at the top of the highest truss 2 (e.g., ...). Figure 1(As shown). The external dimensions of flanges A and B are both smaller than the internal opening size of cavity 62, allowing these two flange sizes to be lowered through cavity 62. The external dimensions of flange C are larger than the internal dimensions of cavity 62, allowing flange C to be fitted snugly against the upper surface of the bearing plate 6. Alternatively, truss 2 can be made in three specifications to facilitate installation. All three specifications are designed as standard sections. When multiple truss sections 2 are needed, the truss 2 with flange A 24 is used as the first truss section 2 and lowered from cavity 62. Then, truss sections 2 with flanges B 24 at both ends are assembled and lowered sequentially, connecting the two truss sections 2 with the assembled flanges B 24. Finally, the truss 2 with flange C 24 is lowered as the last truss section 2.

[0061] like Figure 2 As shown, each pair of uprights 21 is connected by multiple horizontal bars 22, and each pair of horizontal bars 22 is connected by diagonal braces 23, which are also connected to the uprights 21.

[0062] The foot spikes 25 are conical in shape, making it easy for the truss 2 to be inserted into rock crevices on steep slopes. A surveying instrument is mounted on the upper part of the truss 2, enabling real-time monitoring of the borehole angle. For example... Figure 11 As shown, manual or electric winches 11 are installed at the four corners of the floating platform 7. One end of the anchoring rope 12 is connected to the winch 11, and the other end is anchored to the banks of the reservoir via anchor piles 13. When the drilling angle deviation exceeds 0.5°, the angle of the truss 2 is adjusted to the design angle by moving the floating platform 7 by raising and lowering the anchoring rope 12 through the winches 11.

[0063] like Figure 1 As shown, the sleeve 1 is a watertight sleeve, which passes through the through hole 26 inside the truss 2. The sleeve 1 and the through hole 26 are clearance fit, so that when drilling in deep water and steep slopes, the sleeve 1 can "lie obliquely" in the inner cavity of the truss 2 together with the truss 2, avoiding the problem of the slender watertight sleeve 1 bending and breaking due to insufficient rigidity when it is tilted and only constrained at both ends.

[0064] like Figure 1 As shown, the floating platform 7 includes a deck 71, steel beams 72, mounting bolts 73, and pontoons 74. The pontoons 74 are located at both ends of the truss 2 in the Y direction and extend along the X direction. A cavity 75 is formed between the two pontoons 74. The deck 71 is mounted on the pontoons 74 closest to the truss 2. Multiple steel beams 72 are arranged along the X direction on the pontoons 74, and mounting bolts 73, which are selected as U-bolts, are mounted on the steel beams 72 to encircle the pontoons 74. The steel beams 72 closest to the truss 2 are connected to the deck 71, and the steel beams 72 furthest from the truss 2 connect the pontoons 74 at both ends in the Y direction. The steel beams 72 can be made of I-beams.

[0065] like Figure 1 , Figure 4 As shown, two telescopic cylinders 3 are installed at each end of the bearing plate 6 in the Y direction. The cylinder barrels 32 of the two telescopic cylinders 3 at the same end are connected as one unit by a connecting plate 33, ensuring that the casing clamp 4 between the float boxes 74 at both ends can be stably supported and moved. The end of the telescopic rod 31 of the telescopic cylinder 3 is connected to the deck 71 by a fastening bolt 34. The telescopic cylinder 3 can extend and retract vertically, realizing the length adjustment of the truss 2 when the water level changes during drilling. This allows the telescopic cylinder 3 to compensate for small changes in water level and prevent the casing 1 and truss 2 from being bent or lifted by the floating platform 7 due to water level changes during drilling on steep slopes.

[0066] like Figure 1 , Figure 7 As shown, when the water level rises, the floating platform 7 rises, and the telescopic rod 31 retracts, preventing the casing 1 and truss 2 from being pulled upwards by the floating platform 7. Figure 1 , Figure 8 As shown, when the water level drops, the floating platform 7 sinks, the telescopic rod 31 extends, and the sleeve 1 and truss 2 are not pressed down by the floating platform 7.

[0067] To ensure the stability of the height of the sleeve 1 and truss 2 after the telescopic rod 31 of the telescopic cylinder 3 is moved into place, in this embodiment, the telescopic cylinder 3 is a hydraulic cylinder with a hydraulic lock, and the water level compensation range and accuracy are 700mm±10mm. When the water level changes slightly, the telescopic rod 31 compensates for the water level; if the water level change exceeds the compensation range of the telescopic rod 31, the upper short truss 2 is added or removed to adapt to the water level change.

[0068] The bearing plate 6 has a vertically penetrating cavity 62 in its middle, and the cavity 62 is triangular. The bottom of the bearing plate 6 has a surrounding plate 61 that encloses the cavity 62. Both flange A 24 and flange B 24 can be lowered through the cavity 62. Flange C 24 is fixed to the bearing plate 6 with bolts.

[0069] like Figure 3 As shown, the bearing assembly 5 is symmetrically arranged at both ends of the bearing plate 6 in the Y direction, and is used to adjust the tilt angle of the truss 2. It includes a shaft 51, a bearing 52, a bearing seat 53, a bearing bolt 54, and a bearing nut 55. Figure 1 , Figure 3 , Figure 4As shown, a bearing seat 53 is respectively provided on the same end of the bearing plate 6 and the connecting plate 33 in the Y direction. That is, the two bearing seats 53 are respectively fixed to the bearing plate 6 or the connecting plate 33 by their respective bearing bolts 54 and bearing nuts 55. Each bearing seat 53 is equipped with a bearing 52, and the shaft 51 connects the two bearings 52. This realizes the hinged connection between the bearing plate 6 and the truss 2 and the cavity 75 of the floating platform 7 (e.g., Figure 6 (As shown).

[0070] The bearing 52 is a large deep groove ball bearing, which can withstand a large radial load. The bearing 52 can rotate the truss 2 and the sleeve 1 along the shaft 51 to adapt to drilling needs at different angles.

[0071] like Figure 1 As shown, the sleeve 1 is detachably equipped with a sleeve clamp 4 for axially limiting the sleeve 1. Figure 4 , Figure 5 As shown, the sleeve holder 4 includes a housing 41, a slip 42, and a base 43. The housing 41 has a V-shaped conical hole 44 that is larger at the top and smaller at the bottom. Two slips 42 are arranged opposite each other in the V-shaped conical hole 44. The sleeve 1 passes through the two oppositely arranged slips 42. The two ends of the housing 41 are mounted on the support plate 6 through the base 43 and bolts.

[0072] The slip 42 is a self-weight slip, with one end being an inclined surface adapted to the inclined wall of the V-shaped conical hole 44, and the other end being a semi-circle adapted to the outer wall of the sleeve 1. The two semi-circles enclose a circular space. As the self-weight slip 42 slides downwards, the space in the middle of the sleeve 1 decreases, thus clamping the sleeve 1.

[0073] This invention also provides a method for drilling holes on steep slopes in deep water, applicable to drilling inclined holes on steep slopes in deep water, comprising:

[0074] Step S1: Obtain the location of the opening on the steep slope, then measure the water depth H and borehole apex angle φ at the opening location, and calculate the horizontal distance D from the floating platform 7 to the opening location and the vertical length L of the truss 2 being lowered (e.g., ...). Figure 9 (as shown); where D=H·tanφ, L=H / cosφ.

[0075] The borehole apex angle φ is the angle between the borehole axis and the vertical line, also known as the borehole zenith angle.

[0076] The inclination was measured by an inclination measuring instrument installed on truss 2.

[0077] Step S2, move the floating platform 7 to a position at a distance from D, such as... Figure 11As shown, manual or electric winches 11 are installed at the four corners of the floating platform 7. One end of the anchoring rope 12 is connected to the winch 11, and the other end is anchored to the surrounding banks of the reservoir through anchor piles 13. The floating platform 7 is located diagonally above the designed borehole on a steep slope. Note that the casing clamp 4 is not installed on the floating platform 7 initially.

[0078] Step S3, lower truss 2 at the location of floating platform 7: as follows Figure 10 As shown, flange A 24 is fixed at the bottom of the first truss section 2, and a steel wire rope 8 is attached to the lower part of the truss section 2. The other end of the steel wire rope 8 is connected to the hoist 9 at the top of the steep slope. Starting from the first truss section 2, the remaining truss sections are assembled one by one and lowered gradually until the length of the truss section 2 is equal to the vertical length L calculated in step S1. Then, the lowering of the truss section 2 is stopped, and the last truss section 2 is fixed to the support plate 6. The hoist 9 can be a winch.

[0079] In step S4, the casing 1 is inserted into the truss 2. A casing holder 4 is installed on the upper part of the casing 1. The drill bit 10 is lowered along the casing 1. The drill bit 10 has a double-center reaming drill bit at the bottom, and the drill rod at the top of the drill bit 10 is suspended by a large hook. The upper parts of the truss 2, casing 1, and drill bit 10 are all connected to the floating platform 7, and the lower parts are suspended in the water.

[0080] Step S5: Start the hoist 9 to tighten the wire rope 8, lifting the truss 2 so that it swings relative to the floating platform 7 towards the steep slope. Since the vertical length L of the truss lowering is the length of the truss 2 in its inclined state when the inclined hole is being opened, when the truss 2 contacts the steep slope, it reaches the opening position. Insert the foot spikes 25 at the bottom of the truss 2 into the rock crevices of the steep slope (e.g.,...). Figure 10 (As shown).

[0081] Step S6: Start drilling with drill string 10. During drilling, truss 2, casing 1, and drill string 10 are all in an inclined state, with the upper part connected to the floating platform 7 and the lower part in contact with the predetermined hole position on the deep water steep slope. From the inside out, the sequence is drill string 10, water-proof casing 1, and truss 2. Truss 2 is inclined, drill string 10 is "lying obliquely" in water-proof casing 1, and water-proof casing 1 is "lying obliquely" in the inner cavity of truss 2. Ultimately, truss 2 bears the larger bending moment, thus preventing the slender water-proof casing 1 from bending and deforming in the inclined state. Drilling is completed.

[0082] This invention also provides another method for drilling holes on steep slopes in deep water, applicable to drilling straight holes on steep slopes in deep water, comprising:

[0083] Step S1: Obtain the location of the opening on the steep slope, then measure the water depth H and borehole apex angle φ at the opening location, and calculate the horizontal distance D from the floating platform 7 to the opening location and the vertical length L of the truss 2 being lowered (e.g., ...). Figure 9(as shown); where D=H·tanφ, L=H / cosφ.

[0084] Step S2, move the floating platform 7 to a position at a distance from D, such as... Figure 11 As shown, manual or electric winches 11 are installed at the four corners of the floating platform 7. One end of the anchoring rope 12 is connected to the winch 11, and the other end is anchored to the surrounding banks of the reservoir through anchor piles 13. The floating platform 7 is located diagonally above the designed borehole on a steep slope. Note that the casing clamp 4 is not installed on the floating platform 7 initially.

[0085] Step S3, lower truss 2 at the location of floating platform 7: as follows Figure 10 As shown, flange A 24 is fixed at the bottom of the first truss 2, and a steel wire rope 8 is tied to the lower part of the truss 2. The other end of the steel wire rope 8 is connected to the hoist 9 at the top of the steep slope. Then, starting from the first truss 2, the remaining trusses 2 are assembled section by section and lowered step by step until the length of the truss 2 is equal to the vertical length L calculated in step S1. Then, the lowering of the truss 2 is stopped, and the last truss 2 is fixed on the support plate 6.

[0086] Step S4: Insert the sleeve 1 into the truss 2, start the hoist 9 to tighten the wire rope 8, and lift the truss 2, causing the truss 2 to swing relative to the floating platform 7 towards the steep slope until the truss 2 contacts the steep slope, reaching the opening position, and fix the truss 2 on the steep slope; remove the sleeve clamp 4 (e.g., Figure 12 (As shown), so that the sleeve 1 is in a free state that can move up and down;

[0087] Step S5: Start drill string 10 and use a double-center reaming drill bit for low-pressure inclined drilling. After drilling to a certain depth, such as 0.3m-0.4m, lift drill string 10 to drive the drill bit to grind the hole wall. Lower drill string 10 again, and then lift drill string 10 again to drive the drill bit to grind the hole wall. Repeat this process several times to enlarge the hole diameter (e.g., ...). Figure 13 (as shown);

[0088] Step S6: Raise the drill string 10 so that the drill bit is inside the casing 1, keeping the bottom of the truss 2 stationary at the opening position, and move the floating platform 7 a certain distance towards the steep slope to reduce the borehole apex angle. The cylinder 32 of the telescopic cylinder 3 is lifted by the truss 2, and the upper part of the truss 2 extends out of the floating platform 2, compensating for the change in the length of the underwater truss 2. If the compensation capacity of the telescopic cylinder 3 is insufficient, the upper truss 2 needs to be disassembled. The upper part of the truss 2 should preferably be connected with short truss sections of 1m each. Continue the above operation with low-pressure inclined drilling, repeating this 2-3 times until the floating platform 7 reaches directly above the predetermined borehole position (as shown in the figure);

[0089] Step S7: Start the drilling tool 10 and drill a footing platform for the casing 1 near the predetermined hole position on the steep slope to complete the "nesting" work of drilling a straight hole in deep water steep slope (as shown in the figure); thereby solving the technical problem that the casing 1 slides down the slope and cannot take root when drilling a straight hole on a deep water steep slope, so that the casing 1 stands stably and vertically at the predetermined hole position.

[0090] In step S8, the drill string 10 is raised so that the drill bit is placed inside the casing 1, and the bottom of the casing 1 is placed on the aforementioned foot platform (as shown in the figure). Then the drill string 10 is started to drill a straight hole.

[0091] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A deep-water steep slope drilling device, comprising a casing (1), characterized in that, It also includes a truss (2), a sleeve clamp (4), a floating platform (7), a bearing plate (6), a bearing device (5), and a telescopic cylinder (3). The end of the truss (2) is provided with a through hole (26) for the sleeve (1) to pass through. The sleeve (1) is located inside the truss (2). The truss (2) is hinged to the floating platform (7). The sleeve clamp (4) for axially limiting the sleeve (1) is detachably provided on the sleeve (1). The floating platform (7) has a cavity (75) that is open at one or both ends in the X direction; the sleeve (1) passes through the support plate (6), the lower end of the support plate (6) is connected to the truss (2), the upper end of the support plate (6) is provided with the sleeve clamp (4), the cylinder of the telescopic cylinder (3) is connected to the support plate (6) through the bearing device (5), and the telescopic rod of the telescopic cylinder (3) is vertically connected to the floating platform (7); The bearing device (5) enables the bearing plate (6) and its connected truss (2) to tilt and swing relative to the floating platform (7) about a horizontal axis within the cavity (75). The telescopic cylinder (3) is used to change the relative position of the truss and the platform during the steep slope opening process to adapt to the change of the truss in the tilt angle.

2. The deep-water steep slope drilling device according to claim 1, characterized in that, Two telescopic cylinders (3) are provided at each end of the bearing plate (6) in the Y direction, and the cylinder barrels of the two telescopic cylinders (3) at the same end are connected by a connecting plate (33); the bearing device (5) is connected to the bearing plate (6) and the connecting plate (33).

3. The deep-water steep slope drilling device according to claim 2, characterized in that, The bearing device (5) includes a shaft (51), a bearing (52) and a bearing seat (53). A bearing seat (53) is respectively provided on the same end of the bearing plate (6) and the connecting plate (33) in the Y direction. Each bearing seat (53) is equipped with a bearing (52). The shaft (51) connects the two bearings (52).

4. The deep-water steep slope drilling device according to claim 1, characterized in that, The sleeve holder (4) includes a shell (41), a slip (42) and a base (43). The shell (41) has a V-shaped conical hole (44) that is larger at the top and smaller at the bottom. Two slips (42) are arranged opposite each other in the V-shaped conical hole (44). The sleeve (1) passes between the two oppositely arranged slips (42). The two ends of the shell (41) are mounted on the truss (2) through the base (43).

5. The deep-water steep slope drilling device according to claim 1, characterized in that, The floating platform (7) includes a deck (71), steel beams (72), mounting bolts (73), and pontoons (74). The pontoons (74) are located at both ends of the truss (2) in the Y direction and extend along the X direction. The deck (71) is located on the pontoons (74) near the truss (2). Multiple steel beams (72) are arranged along the X direction on the pontoons (74). Mounting bolts (73) that can encircle the pontoons (74) are provided on the steel beams (72). The steel beams (72) near the truss (2) are connected to the deck (71), and the steel beams (72) away from the truss (2) connect the pontoons (74) at both ends in the Y direction.

6. The deep-water steep slope drilling device according to claim 1, characterized in that, The truss (2) includes uprights (21), horizontal bars (22), diagonal braces (23), flanges (24), foot nails (25), and through holes (26). The uprights (21) are arranged in a triangular pattern on the flanges (24), and both ends of the uprights (21) are connected through the flanges (24). Each pair of uprights (21) is connected by multiple horizontal bars (22), and each pair of horizontal bars (22) is connected by diagonal braces (23). Multiple foot nails (25) are provided on the lower end face of the flanges (24) at the bottom of the truss (2).

7. A method for drilling holes in deep water on steep slopes, using the deep water steep slope drilling device as described in any one of claims 1-6, characterized in that, include: 1) Obtain the location of the opening on the steep slope, then obtain the water depth H and the borehole apex angle φ at the opening location, and calculate the horizontal distance D from the floating platform (7) to the opening location and the vertical length L of the truss (2) being lowered; 2) Move the floating platform (7) to a position at a distance of D and anchor it; 3) Lower the truss (2) at the location of the floating platform (7): Tie a steel wire rope (8) to the lower part of the truss (2), and connect the other end of the steel wire rope (8) to the hoist (9) at the top of the steep slope; then assemble the remaining trusses (2) section by section from the truss (2) and lower them gradually until the length of the truss (2) is equal to the vertical length L calculated in step 1), and then stop lowering the truss (2); 4) Insert the casing (1) into the truss (2), install the casing clamp (4) on the upper part of the casing (1), and lower the drill bit (10) along the casing (1). The upper parts of the truss (2), casing (1) and drill bit (10) are all connected to the floating platform (7), and the lower parts are suspended in the water. 5) Start the hoist (9) and tighten the wire rope (8) to lift the truss (2) so that the truss (2) is tilted relative to the floating platform (7) towards the steep slope until the truss (2) contacts the steep slope and reaches the opening. Fix the truss (2) on the steep slope. 6) Start the drill bit (10) to complete the drilling.

8. A method for drilling holes in deep water on steep slopes, using the deep water steep slope drilling device as described in any one of claims 1-6, characterized in that, include: 1) Obtain the location of the opening on the steep slope, then obtain the water depth H and the borehole apex angle φ at the opening location, and calculate the horizontal distance D from the floating platform (7) to the opening location and the vertical length L of the truss (2) being lowered; 2) Move the floating platform (7) to a position at a distance of D and anchor it; 3) Lower the truss (2) at the location of the floating platform (7): Tie a steel wire rope (8) to the lower part of the truss (2), and connect the other end of the steel wire rope (8) to the hoist (9) at the top of the steep slope; then assemble the remaining trusses (2) section by section from the truss (2) and lower them gradually until the length of the truss (2) is equal to the vertical length L calculated in step 1), and then stop lowering the truss (2); 4) Insert the sleeve (1) into the truss (2), start the hoist (9) to tighten the wire rope (8) and lift the truss (2) so that the truss (2) tilts relative to the floating platform (7) towards the steep slope until the truss (2) contacts the steep slope and reaches the opening part. Fix the truss (2) on the steep slope; remove the sleeve clamp (4). 5) Start the drill bit (10) to perform inclined drilling. After reaching a certain drilling depth, lift the drill bit (10) to drive the drill bit to grind the hole wall. Then lower the drill bit (10) and lift it up again. Repeat this process several times to enlarge the hole diameter. 6) Raise the drill bit (10) so that the drill bit is inside the casing (1), keep the bottom of the truss (2) in the opening position, move the floating platform (7) a certain distance in the direction of the steep slope, so that the truss (2) gradually stands upright and the upper part extends out of the floating platform (7) until the truss (2) reaches directly above the opening position. 7) Start the drill bit (10) to complete the drilling.

Images