A method of offshore push-the-bit pipe following drilling

Abstract

The application discloses a kind of offshore inner drive type follow pipe drilling technical method, it is related to follow pipe drilling field, including outer drilling tool assembly and inner drilling tool assembly, the inner drilling tool assembly is arranged in the inside of outer drilling tool assembly, and axis coincides with each other, the outer drilling tool assembly is from bottom to top by casing head, casing and casing hanger, the inner drilling tool assembly is from bottom to top by inner drilling head, flow joint, screw motor, drill pipe, casing hanger running tool composition.The inner drilling tool of the application drives casing head rotation, the drilling quality of cutting is better, the casing is more smooth, and the follow pipe efficiency is higher, the inner drilling tool of drilling tool combination does not exceed casing bottom, there is no telescopic movable part, and follow pipe drilling can be quickly unlocked and separated after completion, without the risk of failure.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of pipe following drilling, in particular to a sea internal driving pipe following drilling technology method. BACKGROUND

[0002] Pipe following drilling is a high-efficiency drilling process in which casing is simultaneously lowered during drilling, thereby reducing the number of tripping operations. Meanwhile, this method is suitable for drilling holes prone to wall collapse and diameter reduction, preventing the occurrence of situations in which the casing cannot be lowered or is blocked after the hole is drilled.

[0003] Conventional pipe following drilling usually adopts the method of leading drilling with an inner drilling tool, the inner drilling tool exceeds the bottom of the casing by a long distance, and a long drilling pocket needs to be left, an eccentric reamer or a hydraulic telescopic reamer is used for reaming drilling, and the passability of the inner drilling tool and the reamer in the casing also needs to be considered. The eccentric reamer has a small reaming diameter and poor drilling tool stability, resulting in poor drilling quality and low pipe following drilling efficiency. The hydraulic telescopic reamer has a complex mechanical structure and poor reliability, and the cutting blades cannot be retracted due to mud and sand blocking.

[0004] The existing pipe following drilling method adopts the conventional drilling method of drilling a hole first and then lowering a casing, the hole is cut by a leading drilling tool, the casing does not rotate and has no cutting ability, the quality of the hole drilled by the leading reaming drilling is not high, the friction between the casing and the hole is large, resulting in serious drag pressure and low footage efficiency; the reamer adopts a hydraulic telescopic reamer, the mud content of the seabed stratum is high, and sometimes it is accompanied by gravel, which easily causes the reaming cutting blades to be blocked during drilling, resulting in the inability to be retracted, and the inability to pass through the inside of the casing, causing the risk of failure of the inner and outer drilling tools to be released; the existing casing hanging and feeding tool is connected with the suspension joint through the reverse rotation locking and forward rotation unlocking mode, and there is a risk of release when the drilling rod is forward rotated in advance, therefore the drilling rod and the casing cannot be rotated during the pipe following drilling process, and once the drilling is stuck, the casing cannot be released by rotating the casing; the suction effect during the tripping process easily causes the hole wall to collapse, and it is difficult for the casing to re-enter the hole, and the casing is easily blocked or cannot be lowered into place. SUMMARY

[0005] Therefore, the present application aims to provide a sea internal driving pipe following drilling technology method to solve the technical problems of the existing pipe following drilling method, i.e., the suction effect during the tripping process easily causes the hole wall to collapse, and it is difficult for the casing to re-enter the hole.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solution: a sea internal driving pipe following drilling tool, comprising an outer drilling tool assembly and an inner drilling tool assembly, the inner drilling tool assembly is arranged inside the outer drilling tool assembly, and the axes thereof coincide with each other, the outer drilling tool assembly is composed of a casing drill bit, a casing and a casing hanger from bottom to top, and the inner drilling tool assembly is composed of an inner drill bit, a flow divider, a screw motor, a drill rod and a casing hanging and feeding tool from bottom to top.

[0007] By adopting the technical scheme, the inner drilling tool drives the casing drill bit to rotate, the drilling quality is good, the casing is smoothly lowered, the pipe following efficiency is high, the inner drilling tool does not exceed the bottom of the casing, there is no telescopic movable part, and the pipe following drilling is completed to quickly realize the unlocking and separation, and there is no risk of failure.

[0008] The application further provides that the total length of the outer drilling tool assembly and the inner drilling tool assembly is matched.

[0009] By adopting the technical scheme, the outer drilling tool assembly and the inner drilling tool assembly can be connected.

[0010] The application further provides that the casing drill bit is sequentially composed of an outer rotary cutting head, an outer fixed joint, a ball bearing and a torque transmission pin from outside to inside.

[0011] By adopting the technical scheme, the outer rotary cutting head can be driven by the inner drill bit to move, and the torque transmission pin is made of brass or other cuttable materials.

[0012] The application further provides that the outer rotary cutting head and the outer fixed joint are connected through the ball bearing, and the outer fixed joint and the casing are connected through threads.

[0013] By adopting the technical scheme, the outer rotary cutting head can rotate.

[0014] The application further provides that the casing hanging and feeding tool is composed of a feeding body, an axial locking pin, an inner sliding sleeve and a shearing pin.

[0015] By adopting the technical scheme, when the inner drilling tool assembly is assembled, the inner drill bit, the flow distribution joint, the screw motor, the drill pipe with a fixed length are sequentially connected from bottom to top, and the casing hanging and feeding tool is connected at the uppermost part.

[0016] The application further provides that the feeding body is externally provided with an outer hexagon, the casing hanging is internally provided with an inner hexagon, the outer hexagon and the inner hexagon are matched with each other, the feeding body is circumferentially provided with a plurality of axial locking pins, the casing hanging is internally provided with a W ring groove, and the axial locking pins are matched with the W ring groove.

[0017] By adopting the technical scheme, the casing hanging and feeding tool enters the inside of the casing hanging, the outer hexagon is matched with the inner hexagon, the axial locking pins are matched with the W ring groove, the inner drill bit enters the inside of the casing drill bit, and the torque transmission key groove of the inner drill bit is matched with the torque transmission pin of the casing drill bit.

[0018] A sea inner driving pipe following drilling method comprises the following steps:

[0019] Step one: the outer drilling tool assembly is assembled, the casing bit is assembled in advance, and the casing bit is clamped on the drilling machine rotary table, the upper casing is connected in sequence, the casing extends into the seawater, the length of the casing reaches the expected length, the uppermost casing is connected to the casing hanger, and the casing hanger is fixed on the drilling ship deck wellhead;

[0020] Step two: the inner drilling tool assembly is assembled, the inner bit, the flow divider, the screw motor, the fixed-length drill pipe are connected in sequence from bottom to top, the uppermost casing hanger feeding tool is connected, the inner sleeve and the shear pin are not installed, the casing hanger feeding tool enters the inside of the casing hanger, the outer six sides cooperate with the inner six sides, the axial locking pin corresponds to the W ring groove position, and the inner bit enters the casing bit, and the inner bit circumferential torque key groove cooperates with the casing bit torque pin. Then the inner sleeve is put into the feeding tool, the inner sleeve extrudes the axial locking pin, the axial locking pin engages the W ring groove, and after locking is completed, a plurality of shear pins are put into the outer part of the feeding body in the circumferential direction, the inner sleeve is axially fixed in the inner part of the feeding body, and after installation is completed, the sealing plug is screwed outside the shear pin. As the drilling depth increases, the ship-borne drilling machine continuously adds the drill pipe;

[0021] Step three: after the drilling tool assembly is completed, the casing hanger is connected to the drill pipe, the whole drilling tool assembly is lowered into the water until the drill bit contacts the seabed mud surface, at this time the mud pump is started to deliver mud into the drilling tool, the mud is delivered into the screw motor through the drill pipe, the casing hanger feeding tool, the intermediate connecting drill pipe, the mud drives the screw motor to work, the screw motor drives the lower flow divider and the inner bit to rotate, the inner bit drives the casing bit to rotate through the circumferential torque pin, and the inner and outer bits rotate simultaneously to cut the formation and drill.

[0022] Step four: until drilling to the specified depth, the casing hanger approaches the mud surface, or the casing hanger enters the inside of the wellhead head placed in the early stage, the casing is lowered and the drilling is stopped, the pump is stopped, the hanging weight is measured, the uppermost drill pipe is disconnected, the steel ball is put in, the upper drill pipe is reconnected, the mud pump is started, the mud pump pressure of the ship-borne drilling machine is observed, the pressure suddenly decreases after the pressure suddenly increases to the specified pressure, at this time it is judged that the feeding tool is unlocked, the pump is stopped, the upper drill pipe is lifted 1-2m, and it is observed whether the hanging weight is reduced. The reduced value is close to the weight of the outer drilling tool assembly in water, it is judged that the inner and outer drilling tools are successfully unlocked, the inner bit is separated from the casing bit, the casing hanger feeding tool is separated from the casing hanger, and the inner drilling tool assembly is lifted and recovered.

[0023] Step five: the next level small specification drilling tool assembly is assembled, enters the seabed borehole, and is slowly lowered to the vicinity of the casing bit. When the bottom is contacted, the hanging weight can be observed to be reduced, at this time the drill bit contacts the protruding torque pin in the casing bit, the mud pump is started and the drilling tool is rotated, the drill bit cuts the protruding torque pin, the torque pin is brass or other cuttable material, the drill bit quickly cuts it off, and the next level drilling is continued after cutting.

[0024] In summary, the present application has the following advantages:

[0025] The present application has better drilling quality by rotating the inner drilling tool driving the casing drill bit, and the casing is more smoothly lowered and the pipe following efficiency is higher;

[0026] The present application has no telescopic movable part by adopting the inner drilling tool of the drilling tool combination not exceeding the bottom of the casing, and the unlocking and separation can be quickly realized after the pipe following drilling is completed, without the risk of failure to release;

[0027] The present application adopts the casing hanging running tool capable of transmitting torque, and can bear higher torque by the ball unlocking mode, without worrying about the problem of early unlocking caused by reverse torque of the drilling tool, in addition, the drilling machine can drive the casing to rotate together through the drill pipe, together with the bottom power driven rotation to form a composite rotation, reducing the risk of pipe following casing drilling jam. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is a pipe following drilling tool combination assembly drawing of the present application;

[0029] Figure 2 It is a pipe following drilling tool combination sectional view of the present application;

[0030] Figure 3 It is an outer pipe assembly assembly drawing of the present application;

[0031] Figure 4 It is an outer pipe assembly sectional view of the present application;

[0032] Figure 5 It is an inner drilling tool assembly appearance drawing of the present application;

[0033] Figure 6 It is an inner drilling tool assembly sectional view of the present application;

[0034] Figure 7 It is a casing drill bit appearance drawing of the present application;

[0035] Figure 8 It is a casing drill bit sectional view of the present application;

[0036] Figure 9 It is an inner drill bit appearance drawing of the present application;

[0037] Figure 10 It is a casing hanging appearance drawing of the present application;

[0038] Figure 11 It is a casing hanging sectional view of the present application;

[0039] Figure 12 It is a casing hanging running tool appearance drawing of the present application;

[0040] Figure 13 It is a casing hanging running tool locking state sectional view of the present application;

[0041] Figure 14 This is a cross-sectional view of the casing inserting tool of the present invention in the unlocked state.

[0042] In the diagram: 1. External drill assembly; 2. Internal drill assembly; 11. Casing bit; 12. Casing; 13. Casing hanger; 21. Internal drill bit; 22. Diverter; 23. Screw motor; 24. Drill pipe; 25. Casing hanger feed tool; 111. External rotary cutting head; 112. External fixed joint; 113. Ball bearing; 114. Torque transmission pin; 221. Torque transmission keyway; 131. W-ring groove; 132. Internal hexagon; 2551. External hexagon; 251. Feed body; 252. Axial locking pin; 253. Internal sliding sleeve; 254. Shear pin; 255. Steel ball; 2531. Unlocking ring groove. Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0044] The embodiments of the present invention will now be described.

[0045] A type of offshore internal drive casing drilling tool, such as Figures 1-14 As shown, the assembly includes an outer drill bit assembly 1 and an inner drill bit assembly 2. The inner drill bit assembly 2 is located inside the outer drill bit assembly 1, and their axes coincide. The outer drill bit assembly 1 consists of a casing drill bit 11, a casing 12, and a casing hanger 13 from bottom to top. The inner drill bit assembly 2 consists of an inner drill bit 21, a flow divider 22, a screw motor 23, a drill rod 24, and a casing hanger feed tool 25 from bottom to top. The length of the inner drill bit assembly 2 matches the length of the outer drill bit assembly 1, ensuring that several torque transmission keyways 221 on the circumference of the inner drill bit mate with the torque transmission pins 114 of the casing drill bit 11. When the casing is engaged, the casing insertion tool 25 enters the casing holder 13. The axial locking pin 252 can be pushed out by the inner sliding sleeve 253. When locked, the inner sliding sleeve is fixed to the fixed position of the insertion body 251 by the shear pin 254. When unlocking, a steel ball 255 is inserted into it. Under the action of mud pressure, a downward pressure is generated to shear the shear pin 254. The inner sliding sleeve 253 moves down and the inner sliding sleeve 253 unlocks the annular groove 2531 corresponding to the axial locking pin 252. At this time, the inner drill bit 21 is lifted, and the axial locking pin 252 can be squeezed into the body of the hanger to realize the unlocking.

[0046] Please see Figure 1, the outer rotary cutting head 111, the outer fixed joint 112, the ball bearing 113 and the torque transmission pin 114 are sequentially arranged from the outside to the inside, the outer fixed joint 112 is connected with the upper sleeve 12 through threads, and the outer fixed joint 112 does not rotate, the torque transmission pin 114 protrudes from the inner wall of the outer rotary cutting head 111 and cooperates with the torque transmission key groove 221 of the inner drill bit 21, and the outer rotary cutting head can be driven to rotate by the inner drill bit 21, and the torque transmission pin 114 is made of brass or other cuttable materials.

[0047] Please refer to Figure 1 , the outer rotary cutting head 111 is connected with the outer fixed joint 112 through the ball bearing, and the outer fixed joint 112 is connected with the sleeve 12 through threads, so that the outer rotary cutting head 111 can rotate.

[0048] Please refer to Figure 2 , the casing hanger running-in tool 25 is composed of a running-in body 251, an axial locking pin 252, an inner sliding sleeve 253 and a shearing pin 254, and the inner drill assembly 2 is sequentially connected from bottom to top when assembled, that is, the inner drill bit 21, the flow divider joint 22, the screw motor 23, the drill pipe 24 with a fixed length and the casing hanger running-in tool 25 which is not locked at the uppermost part.

[0049] Please refer to Figure 2 , the running-in body 251 is externally provided with an outer hexagon 2551, the casing hanger 13 is internally provided with an inner hexagon 132, the outer hexagon 2551 cooperates with the inner hexagon 132, the running-in body 251 is circumferentially provided with a plurality of axial locking pins 252, the casing hanger 13 is internally provided with a W-shaped ring groove 131, the axial locking pin 252 cooperates with the W-shaped ring groove 131, the casing hanger running-in tool 25 enters the inside of the casing hanger 13, the outer hexagon 2551 cooperates with the inner hexagon 132, the axial locking pin 252 corresponds to the position of the W-shaped ring groove 131, at the same time, the inner drill bit 21 enters the inside of the casing drill bit 11, and the circumferential torque transmission key groove 221 of the inner drill bit 21 cooperates with the torque transmission pin 114 of the casing drill bit 11.

[0050] A method for offshore inner drive pipe following drilling, comprising the following steps:

[0051] Step one: assemble the outer drill assembly, the casing drill bit is assembled in advance, clamped on the rotary table of the drilling machine, sequentially connected with the upper sleeve, the casing extends into the sea water, and the length of the casing reaches the expected running-in length, the uppermost casing is connected with the casing hanger, and the casing hanger is fixed on the wellhead on the deck of the drilling ship;

[0052] Step two: the inner drilling tool assembly is assembled from bottom to top, sequentially connecting the inner drill bit, the flow divider, the screw motor, the drill pipe of a certain length, and the upper part of the casing hanger running tool, which is the inner sliding sleeve and the shear pin, which is not installed. The casing hanger running tool enters the inside of the casing hanger, the outer six sides cooperate with the inner six sides, the axial locking pin corresponds to the W ring groove position, at the same time, the inner drill bit enters the casing drill bit, and the inner drill bit circumferential torque key groove cooperates with the casing drill bit torque pin. Then, the inner sliding sleeve is placed in the running tool, the inner sliding sleeve extrudes the axial locking pin, the axial locking pin engages the W ring groove, and after locking is completed, a plurality of shear pins are placed in the circumferential direction outside the running tool, the inner sliding sleeve is axially fixed inside the running tool, and after installation is completed, the sealing plug is screwed outside the shear pin. As the drilling depth increases, the ship-borne drilling machine continuously adds drill pipes, the screw motor has a centralizer to ensure that it is centered inside the casing and reduce vibration during rotation.

[0053] Step three: after the drilling tool assembly is completed, the upper part of the casing hanger is connected to the drill pipe, and the entire drilling tool assembly is lowered into the water until the drill bit contacts the seabed mud surface. At this time, the mud pump is started to deliver mud into the drilling tool. The mud passes through the drill pipe, the casing hanger running tool, the intermediate connecting drill pipe, and enters the screw motor. The mud drives the screw motor to work, and the screw motor drives the lower flow divider and the inner drill bit to rotate. The inner drill bit drives the casing drill bit to rotate through the circumferential torque pin, and the inner and outer drill bits rotate simultaneously to cut the formation and drill. The flow divider can divide the drilling fluid to flush the annulus between the inner drill bit and the casing drill bit, preventing mud and sand from blocking the annulus.

[0054] Step four: until drilling to the specified depth, the casing hanger approaches the mud surface, or the casing hanger enters the wellhead placed in the early stage. The casing is lowered and the drilling is stopped. The pump is stopped, the hanging weight is measured, the uppermost drill pipe is disconnected, the steel ball is put in, the upper drill pipe is reconnected, the mud pump is started, and the ship-borne drilling machine mud pump pressure is observed. When the pressure suddenly decreases after increasing to the specified pressure, it is determined that the running tool is unlocked. Stop the pump, raise the upper drill pipe 1-2m, and observe whether the hanging weight decreases. If the decrease value is close to the weight of the outer drilling tool assembly in water, it is determined that the inner and outer drilling tools are successfully unlocked, the inner drill bit is separated from the casing drill bit, the casing hanger running tool is separated from the casing hanger, and the inner drilling tool assembly is retrieved by raising the drill.

[0055] Step five: assemble the next level of small-scale drilling tool assembly, enter the seabed borehole, and slowly lower it to the vicinity of the casing drill bit. When the bottom is reached, the hanging weight can be observed to decrease. At this time, the drill bit contacts the protruding torque pin inside the casing drill bit. Start the mud pump and rotate the drill. The drill bit cuts off the protruding torque pin, which is made of brass or other cuttable materials. After cutting, the next level of drilling is continued.

[0056] Although the embodiments of the present application have been shown and described, the specific embodiments are merely exemplary and are not to be construed as limiting the present application, and the described specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner, and those skilled in the art can make modifications, replacements and variations to the embodiments without creative contribution after reading the specification, and as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A marine internal-drive casing drilling tool, comprising an outer drill string assembly (1) and an inner drill string assembly (2), wherein the inner drill string assembly (2) is disposed inside the outer drill string assembly (1) and their axes coincide, characterized in that: The external drill assembly (1) consists of a casing drill bit (11), casing (12), and casing hanger (13) from bottom to top. The internal drill assembly (2) consists of an internal drill bit (21), a flow divider (22), a screw motor (23), a drill rod (24), and a casing hanger feed tool (25) from bottom to top. The casing drill bit (11) consists of an outer rotary cutting head (111), an outer fixed joint (112), a ball bearing (113), and a torque transmission pin (114) from the outside to the inside. The casing hanger feed tool (25) consists of a feed body ( The device consists of an axial locking pin (251), an inner sliding sleeve (253), and a shearing pin (254). The outer hexagon (2551) is provided on the outside of the feeding body (251), and the inner hexagon (132) is provided inside the sleeve hanger (13). The outer hexagon (2551) and the inner hexagon (132) cooperate with each other. Several axial locking pins (252) are arranged around the circumference of the feeding body (251). The sleeve hanger (13) is provided with a W-ring groove (131), and the axial locking pin (252) cooperates with the W-ring groove (131).

2. The offshore internal drive casing drilling tool according to claim 1, characterized in that: The total lengths of the external drill assembly (1) and the internal drill assembly (2) are matched.

3. The offshore internal drive casing drilling tool according to claim 2, characterized in that: The external rotary cutting head (111) is connected to the external fixed joint (112) by ball bearings, and the external fixed joint (112) is connected to the sleeve (12) by threads.

4. A method for offshore internal-drive casing drilling, employing an offshore internal-drive casing drilling tool as described in any one of claims 1-3, characterized in that: Includes the following steps: Step 1: Assembly of external drilling tools. The casing drill bit is assembled in advance and clamped on the drilling rig turntable. The upper casing is connected in sequence. The casing extends into the seawater. After the casing length reaches the expected length, the uppermost casing is connected to the casing hanger, which is fixed to the wellhead on the deck of the drilling vessel. Step 2: Internal drill assembly. From bottom to top, connect the internal drill bit, shunt connector, screw motor, and fixed-length drill rod. At the top, connect the unlocked casing hook feed tool (i.e., the internal sliding sleeve and shear pin are not installed). The casing hook feed tool enters the casing hook, with the outer six-way fitting the inner six-way fitting. The axial locking pin corresponds to the W-ring groove position. At the same time, the internal drill bit enters the casing drill bit, and the circumferential torque transmission keyway of the internal drill bit engages with the torque transmission pin of the casing drill bit. Then, place the internal sliding sleeve into the feed tool. The internal sliding sleeve pushes out the axial locking pin, and the axial locking pin engages with the W-ring groove. After locking, place several shear pins in the circumferential direction outside the feed body to axially fix the internal sliding sleeve inside the feed body. After installation, screw sealing plugs into the outside of the shear pins. As the drilling depth increases, the shipborne drilling rig continuously adds drill rods. Step 3: After the drill string assembly is completed, connect the drill pipe to the upper part of the casing hanger and lower the entire drill string assembly into the water until the drill bit contacts the seabed mud surface. At this time, start the mud pump to deliver mud into the drill string. The mud is fed into the tool through the drill pipe, casing hanger, and intermediate connecting drill pipe, and enters the screw motor. The mud drives the screw motor to work. The screw motor drives the lower distribution connector and the inner drill bit to rotate. The inner drill bit drives the casing drill bit to rotate through several circumferential torque transmission pins. The inner and outer drill bits rotate simultaneously to cut the formation and drill. Step 4: Continue drilling until the specified depth is reached, the casing hanger is close to the mud surface, or the casing hanger enters the previously placed wellhead. Once the casing is in place, stop drilling and stop the pump. Measure the suspended weight, remove the uppermost drill pipe, insert the steel ball, reconnect the upper drill pipe, start the mud pump, and observe the mud pump pressure on the shipboard drilling rig. If the pressure suddenly increases to the set pressure and then suddenly decreases, it indicates that the delivery tool has been unlocked. Stop the pump, raise the upper drill pipe 1-2m, and observe whether the suspended weight has decreased. If the decrease is close to the weight of the outer drilling tool assembly in the water, it indicates that the inner and outer drilling tools have been successfully unlocked. The inner drill bit and the casing drill bit are separated, the casing hanger delivery tool is separated from the casing hanger, and the drill string is lifted to retrieve the inner drilling tool assembly. Step 5: Assemble the next stage of small-sized drill string assembly, enter the subsea borehole, and slowly lower it to the vicinity of the casing drill bit. After touching the bottom, observe the decrease in suspended weight. At this time, the drill bit contacts the protruding torque transmission pin inside the casing drill bit. Start the mud pump and rotate the drill string. The drill bit cuts the protruding torque transmission pin. The torque transmission pin is made of brass or other machinable material. The drill bit quickly removes it. After removal, continue drilling to the next stage.

5. The offshore internal drive casing drilling method according to claim 4, characterized in that: In step two, the screw motor is equipped with a centralizer.

6. The offshore internal drive casing drilling method according to claim 4, characterized in that: In step three, the diversion connector can divert drilling fluid to flush the annular gap between the inner drill bit and the casing drill bit.

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