Abstract
A bottom hole assembly comprising a downhole tool known as a cutting tool is provided for use within a subterranean well for severing tubulars. The cutting tool comprises a fluid source, a gas-driven rotatable motor and a cutting head including one or more cutters. The fluid source supplies pressurized fluid and thereby energy to the gas-driven rotatable motor which is disposed to generate thrust to set the gas-driven rotatable motor in motion. The cutting head is coupled to the gas-driven rotatable motor and rotates while cutting the tubular. The cutting tool can be deployed in a subterranean well by a variety of deployment methods, and the pressurized fluid may be supplied from a surface system, generated inside the cutting tool or bottom hole assembly, or input within the cutting tool or bottom hole assembly prior to deployment.
The invention further relates to associated methods.
Claims
1. A bottom hole assembly for cutting a pipe within a borehole that extends into a subterranean formation, wherein the bottom hole assembly comprises a holding tool for securing the bottom hole assembly to the pipe; and wherein the bottom hole assembly further comprises a cutting tool, and wherein the cutting tool comprises: a pressure chamber; a propellant; an igniter configured to ignite the propellant; a gas-driven rotatable motor comprising one or more fluid passages wherein each of the fluid passages are in fluid communication with an exterior of the bottom hole assembly; a mechanical cutting head coupled to the to the gas-driven rotatable motor; wherein the cutting tool is configured such that upon ignition of the propellant, a pressurized gas is developed in the pressure chamber which is received by the gas-driven rotatable motor, wherein the gas-driven rotatable motor is configured to generate a thrust rotating the motor by exhausting the pressurized gas from the pressure chamber via the one or more fluid passages in the gas-driven rotatable motor to the exterior of the bottom hole assembly.
2. A bottom hole assembly according to claim 1, wherein the holding tool is configured such that upon ignition of the propellant, the pressurized gas is received by the holding tool, thereby securing the bottom hole assembly to the pipe by activating the holding tool from a retracted position to an extended position against the pipe.
3. A bottom hole assembly according to claim 1, further comprising: a holding tool pressure chamber; a holding tool propellant; a holding tool igniter for igniting the holding tool propellant; wherein the holding tool is configured such that upon ignition of the holding tool propellant, the holding tool propellant generates a holding tool pressurized gas which is received by the holding tool pressure chamber thereby activating the holding tool from a retracted position to an extended position against the pipe.
4. A bottom hole assembly according to claim 2, wherein the holding tool is biased in the retracted position and arranged such that: when the holding tool receives the pressurized gas or the holding tool pressurized gas at a pressure at or above a holding tool set-point pressure, the holding tool is forced into the extended position against the pipe; and when the holding tool receives the pressurized gas or the holding tool pressurized gas at a pressure below the holding tool set-point pressure, the holding tool is in the retracted position or in a process of retracting.
5. A bottom hole assembly according to claim 1, wherein the gas-driven rotatable motor and thereby the mechanical cutting head are biased in a stationary position and arranged such that: when the gas-driven rotatable motor receives the pressurized gas at a pressure above a motor set-point pressure, the gas-driven rotatable motor rotates together with the mechanical cutting head; and when the gas-driven rotatable motor receives the pressurized gas at a pressure below the motor set-point pressure, the gas-driven rotatable motor and thereby the mechanical cutting head does not rotate or is in a process of stopping rotation.
6. A bottom hole assembly according to claim 1, wherein the mechanical cutting head comprises at least one cutter, and wherein the cutter is biased in a retracted position within a circumferential envelope of the cutting head and configured such that: when the gas-driven rotatable motor and the mechanical cutting head rotate, the at least one cutter is in an extended position against the pipe; and when the gas-driven rotatable motor and the mechanical cutting head do not rotate, the at least one cutter is in the retracted position or in the process of retracting.
7. A bottom hole assembly according to claim 1, wherein the mechanical cutting head comprises a cutter, and wherein the cutter is biased in a retracted position within a circumferential envelope of the cutting head, and configured such that: when pressurized gas from the pressure chamber applies a pressure to the cutter which is above a cutter set-point pressure, the cutter is in an extended position against the pipe; and when the pressurized gas from the pressure chamber applies a pressure to the cutter which is below the cutter set-point pressure, the at least one cutter is in the retracted position or in a process of retracting.
8. A bottom hole assembly according to claim 1, wherein the mechanical cutting head comprises at least one pivoted arm, wherein each arm is equipped with a cutter and biased in a retracted position within a circumferential envelope of the cutting head, such that: when the gas-driven rotatable motor and the mechanical cutting head rotate, the at least one pivoted arm is in an extended position against the pipe; and when the gas-driven rotatable motor and the mechanical cutting head do not rotate, the at least one pivoted arm is in the retracted position or in the process of retracting.
9. A bottom hole assembly according to claim 8, wherein the one or more pivoted arms are connected to a piston which is configured to move thereby extending the one or more pivoted arms, and wherein the pivoted arms and the piston are biased in a retracted position within the circumferential envelope of the cutting head, and configured such that: when the piston is subject to a pressurized gas above a piston set-point pressure, the one or more pivoted arms are in an extended position towards the pipe; and when the piston is subject to a pressurized gas below the piston set-point pressure, the one or more pivoted arms are in the retracted position or in the process of retracting and the cutters are not in contact with the pipe.
10. A bottom hole assembly according to claim 1, wherein each of the fluid passages in the gas-driven rotatable motor comprises a first portion in fluid communication with the pressure chamber and a second portion in fluid communication with the exterior, and wherein at least the second portion of the one or more fluid passages comprises a center axis and the second portions are spaced apart relative to any other second portion(s) of the other fluid passages, and wherein the center axis of the second portion of each of the one or more fluid passages and a longitudinal axis of the gas-driven rotatable motor are skew lines.
11. A bottom hole assembly according to claim 1, further comprising a gearbox located between the gas-driven rotatable motor and the mechanical cutting head, wherein the gearbox is configured to effectuate a change in a rotational speed of the mechanical cutting head relative to a rotational speed of the gas-driven rotatable motor.
12. A bottom hole assembly according to claim 1, comprising one or more valves for selectively controlling the flow of pressurized gas from the pressure chamber or a holding tool pressure chamber to any one of the following components: the holding tool, the gas-driven rotatable motor, and the mechanical cutting head, thereby controlling activation and de-activation of said component(s) at their respective set-point pressure and allowing and stopping the flow of pressurized gas to any of said components, and wherein the one or more valves is configured to be in communication with a controller controlling the operation of the one or more valves.
13. A method for cutting a pipe within a borehole using a bottom hole assembly according to claim 1, wherein the method comprises the following steps in sequence: selecting an amount of propellant based on in situ wellbore pressure and mass of tubular to be cut; deploying the bottom hole assembly at a given depth within the pipe; activating and setting the holding tool for securing the bottom hole assembly within the pipe; igniting the propellant using the igniter and thereby developing a pressurized gas in the pressure chamber; activating the gas-driven rotatable motor by providing the pressurized gas from the pressure chamber to the gas-driven rotatable motor and exhausting the pressurized gas from the gas-driven rotatable motor to an exterior of the bottom hole assembly, thereby rotating the gas-driven rotatable motor and the mechanical cutting head when the pressure in the pressure chamber is at or above a motor set-point pressure; cutting the pipe mechanically by rotation of the gas-driven rotatable motor and the mechanical cutting head; deactivating the rotation of the gas-driven rotatable motor and thereby the mechanical cutting head when the pressurized gas declines to a pressure below the motor set-point pressure due to exhausting the pressurized gas from the gas-driven rotatable motor to the exterior of the of the bottom hole assembly; deactivating the holding tool; pulling out the bottom hole assembly from the borehole.
14. The method according to claim 13, wherein the igniting step occurs prior to the step of activating and setting the holding tool, the method further comprising: utilizing the gas from the pressure chamber for activating and setting the holding tool when the pressurized gas in the pressure chamber is at or above a holding tool set-point pressure, and wherein deactivating the holding tool occurs when the pressure in the pressure chamber is below the holding tool set-point pressure.
15. The method according to claim 13 wherein the bottom hole assembly further comprises a holding tool pressure chamber, a holding tool propellant and an igniter for igniting the holding tool propellant; the method further comprising the steps of: igniting the holding tool propellant to develop a holding tool pressurized gas inside the holding tool pressure chamber-utilizing the gas from the holding tool pressure chamber for activating and setting the holding tool when the holding tool pressurized gas in the holding tool pressure chamber is at or above a holding tool set-point pressure, and wherein deactivating the holding tool occurs when the pressure in the holding tool pressure chamber is below the holding tool set-point pressure.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0143] Following drawings are appended to facilitate the understanding of the invention. The drawings show embodiments of the invention, which will now be described by way of example only, where:
[0144] FIG. 1 shows schematic of a cutting tool.
[0145] FIG. 2 shows a cross-sectional schematic of a subterranean well.
[0146] FIG. 3 shows a severed tubular.
[0147] FIG. 4 shows a bottom hole assembly within a subterranean well deployed by a fluid pipe.
[0148] FIG. 5A is a view of a cutting tool.
[0149] FIG. 5B is a cross-section view of the cutting tool of FIG. 5A, about line A-A.
[0150] FIG. 6 shows a bottom hole assembly within a subterranean well deployed by a wireline.
[0151] FIG. 7A is a view of a cutting tool including a propellant.
[0152] FIG. 7B is a cross-section view of the cutting tool of FIG. 7A about line B-B.
[0153] FIG. 8 is a cross-section of a cutting tool component, a pressure chamber.
[0154] FIG. 9A is cross-section of a cutting tool component, a gas-driven rotatable motor, about line C-C of FIG. 7B.
[0155] FIG. 9B is an isometric cross-section at 90 degrees of the gas-driven rotatable motor in FIG. 9A.
[0156] FIG. 10A is a side view of the gas-driven rotatable motor.
[0157] FIG. 10B is a cross-section of FIG. 10A about line D-D.
[0158] FIG. 11A is an example of cutting tool comprising a cutting head with cutters in the retracted position.
[0159] FIG. 11B is the cutting head with cutters in the extended position.
[0160] FIG. 12A is an alternate view of the cutting head with cutters in the extended position.
[0161] FIG. 12B is a cross-section of FIG. 12A about line E-E.
[0162] FIG. 13A is a view of a cutting tool including a valve comprising a valve plate, valve plate cover, valve actuator and a fluid communication through passage.
[0163] FIG. 13B is a cross-section view of the cutting tool of FIG. 13A about line G-G.
[0164] FIG. 14 shows schematic of a cutting tool, including two pressure chambers.
[0165] FIG. 15A is a view of a cutting tool including two valves and two pressure chambers.
[0166] FIG. 15B is a cross-section view of the cutting tool of FIG. 15A about line H-H.
[0167] FIG. 16A is a view of a cutting tool including a cutter actuation fluid passage.
[0168] FIG. 16B is a cross-section view of the cutting tool of FIG. 17A about line J-J.
[0169] FIG. 17 is a cross-sectional view about line K-K of FIG. 16B.
[0170] FIG. 18A is a schematic of a bottom hole assembly including a holding tool.
[0171] FIG. 18B shows FIG. 18A in a bottom hole assembly including a holding tool engaging the inner surface of a tubular within a subterranean well.
[0172] FIG. 19A is a bottom hole assembly including a holding tool.
[0173] FIG. 19B is a cross-section of FIG. 19A along line L-L.
[0174] FIG. 20A is a bottom hole assembly including a holding tool and a second pressure chamber.
[0175] FIG. 20B is a cross-section of FIG. 20A along line M-M.
[0176] FIG. 21 shows a schematic of a bottom hole assembly with a cutting tool and a gearbox.
[0177] FIG. 22A is a cutting tool including a gearbox.
[0178] FIG. 22B is a cross-section of FIG. 22A along line N-N.
[0179] FIG. 23A is an isometric view of a gearbox which may form part of the bottom hole assembly.
[0180] FIG. 23B is an alternate isometric view of the gearbox in FIG. 23A.
[0181] FIG. 24 is a schematic of a bottom hole assembly including a holding tool and a controller module.
[0182] FIG. 25A through 25F are schematics of steps for a method of use of a bottom hole assembly including a cutting tool.
[0183] FIG. 26 is signal schematic for a bottom hole assembly including a cutting tool.
[0184] FIG. 27A is a cross-section view of one embodiment of a cutting tool.
[0185] FIG. 27B is a cross-section view of FIG. 27A about line O-O.
[0186] FIG. 28 is a close-up view of an area P of FIG. 27A indicated by the dashed box labelled P on FIG. 27A.
[0187] FIG. 29 is one alternative embodiment of a pressure chamber including a gas-driven rotatable motor shaft with a fluid passage hole, a shaft recess, and a threaded end, which may form part of the bottom hole assembly
[0188] FIG. 30 is a cross-section view of one embodiment of a cutting tool with a through-shaft.
[0189] FIG. 31 is a cross-section partial view of an embodiment of a cutting tool with a gas-driven motor biasing mechanism.
[0190] FIG. 32 is a cross-section partial view of an embodiment of a cutting tool with pivoted arms and a pivoted arm biasing mechanism.
[0191] FIG. 33 is a chart of pressure vs. time; schematically showing various pressure set-points, step, and conditions, of the bottom hole assembly.
DETAILED DESCRIPTION OF PREFERENTIAL EMBODIMENTS
[0192] FIG. 1 shows a schematic of a cutting tool 10, including a pressure chamber 20, a gas-driven rotatable motor 40, and a cutting head 60. The cutting tool 10 may be used in a subterranean well 4 as shown in FIG. 2.
[0193] FIG. 2 is showing a cross-section schematic of a subterranean well 4 with several tubulars/pipes 6, where the inner tubular 6 is equipped with a packer 3.
[0194] FIG. 3 is showing a schematic of the preferred result from use of the cutting tool 10, a tubular 6 with a cut 11 therethrough.
[0195] FIG. 4 is a schematic of a bottom hole assembly 2 deployed by a fluid pipe 13 in a subterranean well 4 having a tubular 6 with an inner surface 9 and an uphole direction 8 and a downhole direction 7. The bottom hole assembly 2 is connected to surface and thereby deployed by a fluid pipe 13 through which the pressurized fluid 115 generated at surface may be supplied to the pressure chamber 20 of the cutting tool/bottom hole assembly. The fluid pipe 13 is connected at top connector 15 of the bottom hole assembly 2, which also includes the pressure chamber 20, a gas-driven rotatable motor 40, and a cutting head 60. A surface system 22 is located at surface.
[0196] FIG. 5A is showing a view of a cutting tool 10 connected to surface and thereby deployed by a fluid pipe 13; and includes a pressure chamber 20, a gas-driven rotatable motor 40, and a cutting head 60.
[0197] FIG. 5B is a cross-section view of the cutting tool 10 of FIG. 5A about line A-A. The pressure chamber 20 is in fluid communication with the fluid pipe 13 and thereby may receive the pressurized fluid 115. The pressure chamber 20 includes one or more fluid passage ports 30 at a lower end of the pressure chamber 20 and a toroidal fluid passage 31 connected thereto, which provides fluid communication to the gas-driven rotatable motor 40. An outer rotary seal 24 is disposed on the outside of the toroidal fluid passage 31 and an inner rotary seal 25 is disposed on the inside of the toroidal fluid passage 31, each functioning to maintain fluid communication from the pressure chamber 20 to the gas-driven rotatable motor 40. The gas-driven rotatable motor 40 rotates about an extended portion of the pressure chamber 20, e.g. a gas-driven rotatable motor shaft 41. The gas-driven rotatable motor 40 and the cutting head 60 rotate about the gas-driven rotatable motor shaft 41 on bearings 26. A bottom nut 63 retains the cutting head 60 to the gas-driven rotatable motor 40.
[0198] FIG. 6 is showing a schematic of a bottom hole assembly 2 deployed in a subterranean well 4 having a tubular 6 with an inner surface 9 and an uphole direction 8 and a downhole direction 7. The bottom hole assembly 2 is connected to surface and deployed by a wireline 5 connected at a top connector 15 and includes a pressure chamber 20, a gas-driven rotatable motor 40, and a cutting head 60. A surface system 22 is located at surface and in communication with the bottom hole assembly 2 via the wireline 5.
[0199] FIG. 7A is showing a view of a cutting tool 10 including a control module 80, a pressure chamber 20, a gas-driven rotatable motor 40 and a cutting head 60.
[0200] FIG. 7B is a cross-section view of the cutting tool 10 and the control module 80 of FIG. 7A about line B-B. In FIG. 7B a propellant 28, which is in fluid communication with the pressure chamber 20 via propellant gas passage 19, is shown. The propellant 28 is connected to an ignitor 21 which is in electrical communication via control wires 23 to controller 81 which resides inside the control module 80. When the ignitor 21 is activated by the controller 81, the propellant 28 starts generating pressurized fluid 115. The pressure chamber 20, in which the pressurized fluid 115 is generated by the propellant 28, is in fluid communication with the gas-driven rotatable motor 40 via one or more fluid passage ports 30 at a lower end of the pressure chamber 20, a toroidal fluid passage 31 connected thereto provides fluid communication to the gas-driven rotatable motor 40. An outer rotary seal 24 is disposed on the outside of the toroidal fluid passage 31 and an inner rotary seal 25 is disposed on the inside of the toroidal fluid passage 31, each functioning to maintain fluid communication from the pressure chamber 20 to the gas-driven rotatable motor 40, as the gas-driven rotatable motor 40 rotates about an extended portion of the pressure chamber 20, e.g. around a gas-driven rotatable motor shaft 41. The gas-driven rotatable motor 40 and the cutting head 60 rotate about the gas-driven rotatable motor shaft 41 on bearings 26. A bottom nut 63 retains the cutting head 60 to the fluid-powered motor 40.
[0201] FIG. 8 is showing a cutting tool 10 component, a pressure chamber 20, which includes a propellant holder 29 and the gas-driven rotatable motor shaft 41 with a gas-driven rotatable motor shaft threaded end 42. The pressure chamber 20 additionally includes one or more fluid passage ports 30 and half the toroidal fluid passage, 31A.
[0202] FIG. 9A is showing a cross-section of a cutting tool component, i.e. a gas-driven rotatable motor 40, about line C-C of FIG. 7B. The gas-driven rotatable motor 40 includes fluid passages 43 each comprising a first portion 37 (see FIG. 9B) and a second portion 38. Each first portion 37 may be in fluid communication with a fluid source in the form of a pressurized fluid 115, when the gas-driven rotatable motor is disposed within the cutting tool. The second portions 38 of each fluid passage 43 may be in fluid communication with a fluid exterior the circumferential envelope of the cutting tool (i.e. exterior to the bottom hole assembly). The centre axis 54 of the second portions 38 of the fluid passages 43 are spaced apart relative to the other second portions of the fluid passages 43; the centre axis 54 of the second portions 38 of the fluid passages 43 and the longitudinal axis 48 of the gas-driven rotatable motor are skew lines. The fluid passages 43 are disposed to receive pressurized fluid 115 from the pressure chamber 20 and by the generation of thrust created from exhausting pressurized fluid 115 from the fluid passages 43 and nozzles 45 (i.e. jetting), rotate about the long axis of the cutting tool 10. This setup renders possible rotation of the cutting head 60 by exhausting pressurized fluid out through the fluid passages 43 because the fluid passages 43 are arranged at an angle different from 90 degrees (i.e. non-radial direction) relative a borehole wall encircling the bottom hole assembly in the well 4. To generate thrust of the cutting tool 10 relative the borehole wall, the fluid passages should probably be as tangential as possible to the radius of the bottom hole assembly, for example oriented as indicated in FIG. 9A.
[0203] FIG. 9B is showing a cross-section 90 degrees of the gas-driven rotatable motor 40 in FIG. 9A, where the gas-driven rotatable motor 40 comprises one or more fluid passages 43 in fluid communication with a second half 31B of the toroidal fluid passage 31. The gas-driven rotatable motor 40, further includes a lowered extended portion, a cutting head shaft 46 on which the cutting head 60 is mounted and secured by a bottom nut 63.
[0204] FIG. 10A is showing an alternate view of the gas-driven rotatable motor 40.
[0205] FIG. 10B is a cross-section of FIG. 10A about line D-D in FIG. 10A further showing the one or more fluid passages 43 in fluid communication with a second half 31B of the toroidal fluid passage 31; and the cutting head shaft 46.
[0206] FIG. 11A is showing a cutting tool 10 component, a cutting head 60 with a through-hole 64 in which the cutting head shaft 46 (cutting head shaft 46 not shown in FIG. 11A, see e.g. FIG. 10B) is to be located. The cutters 62 are shown in the retracted position, i.e. in an initial position within a circumferential envelope of the cutting head.
[0207] FIG. 11B is the cutting head 60 with cutters 62 in the extended position, i.e. outside a circumferential envelope of the cutting head, disposed at the end of cutter pistons 61. The cutting head 60 comprises one or more cutters 62, and the cutting head 60 is coupled to and disposed to receive rotational power and thereby centrifugal force from the gas-driven rotatable motor 40, thereby providing energy to extend the cutter pistons 61 and the cutters 62 to create a cut in a tubular 6 surrounding the cutting tool 10.
[0208] FIG. 12A is showing an alternative view of the cutting head 60 with cutters 62 in the extended position.
[0209] FIG. 12B is a cross-section of FIG. 12A about line E-E. The cutter pistons 61 with cutters 62 are extended from the cutter piston chamber 65 due to the rotation of the cutting head 60, i.e. by centrifugal force resulting from rotation of the cutting head. A piston return spring 66 resides on an opposing side of the cutter piston 61 such that when rotation of the cutting head 60 ceases, the pistons 61 may be returned to the retracted position, i.e. to the initial position within a circumferential envelope of the cutting head, by the force of springs 66. Also shown in FIG. 12B is the through-hole 64 in which the cutting head shaft 46 may be located.
[0210] FIG. 13A is showing a view of a cutting tool 10.
[0211] FIG. 13B is a cross-section view of the cutting tool 10 of FIG. 13A about line G-G. A valve plate 50 resides inside pressure chamber 20 and a valve actuator 52 may selectively actuate a valve plate cover 51 to open and close fluid communication through passage 53 in the valve plate 50. In this way, pressurized fluid 115 within the pressure chamber 20 may be selectively provided to the fluid-powered motor 40. The valve actuator 52 is in electrical communication with the controller 80 within the control module 81 via control wires 23. The arrangement shown in FIG. 13B thereby provides a method of creating a second cut in a tubular 6 at a different location. The method comprising the steps of: deploying the bottom hole assembly 2 on wireline 5; positioning the bottom hole assembly 2 within a tubular 6 segment such that the cutting tool 10 is in a desired position to cut the desired section of tubular 6; delivering fluid to the gas-driven rotatable motor 40; rotating the cutting head 60 coupled thereto; cutting the tubular 6; activating the valve actuator 52 thereby putting valve plate cover 51 in a position to stop the flow of pressurized fluid 115 to the gas-driven rotatable motor 40; repositioning the bottom hole assembly 2 to a second position within the tubular 6; retracting valve plate cover 51 and delivering pressurized fluid 115 to the gas-driven rotatable motor 40; rotating the cutting head 60 coupled thereto; cutting the second cut 11 in the tubular 6.
[0212] In one embodiment as shown in FIG. 13B, the valve 49 comprises a valve actuator 52 disposed to actuate a valve plate cover 51 to selectively provide fluid communication through valve plate 50 via a fluid communication through-passage 53 therethrough.
[0213] FIG. 14 shows a schematic of a cutting tool 10, including a cutting head 60, a fluid-powered motor 40 and two pressure chambers 20.
[0214] FIG. 15A is showing a view of a cutting tool 10 with two pressure chambers, i.e. a first and second pressure chamber 20A, 20B.
[0215] FIG. 15B is a cross-section view of the cutting tool 10 of FIG. 15A about line H-H. The cutting tool 10 includes a first pressure chamber 20A including a valve plate 50A with a fluid communication through-passage 53A therethrough and an associated valve plate cover 51A that may be selectively opened and closed by the actuation of valve actuator 52A. The cutting tool 10 further includes a second pressure chamber 20B including a valve plate 50B with a fluid communication through-passage 53B therethrough and an associated valve plate cover 51B that may be selectively opened and closed by the actuation of valve actuator 52B. Each valve actuator 52A and 52B are in electrical communication with the controller 81 in the control module 80 via control wires 23A and 23B, respectively. In this manner, pressurized fluid 115 in pressure chamber 20A may be provided to the gas-driven rotatable motor 40 independently from the provision of pressurized fluid 115 within pressure chamber 20B.
[0216] FIG. 16A is showing a view of a cutting tool 10.
[0217] FIG. 16B is a cross-section view of the cutting tool 10 of FIG. 16A about line J-J in FIG. 16A. The cutting tool 10 includes a cutter actuation fluid passage 47 which establishes fluid communication between the pressure chamber 20 and the cutter piston chambers 65.
[0218] FIG. 17 is a cross-sectional view about line K-K of FIG. 16B. Cutter actuation fluid passage 47 is shown in fluid communication with cutter piston chambers 65 such that when pressurized fluid 115 is delivered from the pressure chamber 20 to the piston chambers 65 via the cutter actuation fluid passage 47, the cutter pistons 61 with cutters 62 are extended. When pressure within piston chambers 65 is depressurized in one way or another when the cut 11 is completed, piston return springs 66 may return the cutter pistons 61 to the retracted position, i.e. to the initial position within a circumferential envelope of the cutting head 60.
[0219] FIG. 18A is showing a schematic of a bottom hole assembly 2 including a cutting tool 10 and a holding tool 90 with holding linkages 91.
[0220] FIG. 18B shows the bottom hole assembly 2 of FIG. 18A deployed in a subterranean well 4 having a tubular 6 with an inner surface 9 and an uphole direction 8 and a downhole direction 7. The bottom hole assembly 2 is connected to surface by a wireline 5 at a top connector 15 and further includes a holding tool 90 with holding linkages 91 actuated to secure the bottom hole assembly 2 to the inner surface 9, a pressure chamber 20, a gas-driven rotatable motor 40 and a cutting head 60. Upon activation, the holding tool 90 engages the tubular 6 to the inner surface 9 of the tubular which is to be severed. In this manner, the wireline 5 is prevented from counter rotating during the cutting process, relative to the rotating components of the cutting tool 10, for example, the gas-driven rotatable motor 40 and the cutting head 60. The holding tool 90 additionally maintains the bottom hole assembly 2 at the desired longitudinal position within the subterranean well 4. A surface system 22 may be located at surface and in communication with the bottom hole assembly 2 via wireline 5.
[0221] FIG. 19A is showing a bottom hole assembly 2 including a cutting tool 10, holding tool 90 with holding linkages 91 and holding pads 92.
[0222] FIG. 19B is a cross-section of FIG. 19A along line L-L. Holding linkages 91 of the holding tool 90 are pinned at an uphole direction 8 of the holding tool 90. Additional holding linkages 91A are pinned to a holding tool actuation piston 94 at the downhole direction 7 of holding tool 90 with holding pads 92 connected therebetween. When pressurized fluid 115 within pressure chamber 20 is communicated through holding tool actuation passage 93 at a pressure sufficient to overcome the force of the holding tool return spring 95, holding tool actuation piston 94 is actuated in an uphole direction 8, thereby extending holding linkages 91 and 91A, and holding pads 92 radially thereby keeping the bottom hole assembly 2 in a fixed position versus the tubular 6 in a subterranean well 4. Thereby the pressurized fluid 115 in pressure chamber 20 may be used to actuate the holding tool 90 as described, and at the same time provide pressurized fluid 115 to the gas-driven rotatable motor 40.
[0223] FIG. 20A is showing a bottom hole assembly 2 including a holding tool 90 and a cutting tool 10 which contains two pressure chambers 20A and 20B.
[0224] FIG. 20B is a cross-section of FIG. 20A along line M-M in FIG. 20A. Pressure chamber 20A is in fluid communication with the gas-driven rotatable motor 40 while pressure chamber 20B is in fluid communication with the holding tool 90. In this manner, pressurized fluid 115 and thereby fluid power, is provided to the fluid-powered motor 40 and the holding tool 90 which may be independently controlled. Each pressure chamber 20A and 20B is provided with pressurized fluid 115 by the activation of ignitor 21 which ignites propellant 28. The activation of propellant 28 is controlled by control wires 23 in electrical communication with the controller 81 in the control module 80. Normally, pressure chamber 20B will be activated first to activate the holding tool 90, then pressure chamber 20A will be activated to activate the gas-driven rotatable motor 40 which then again puts the cutting head 60 in a rotation.
[0225] FIG. 21 is showing a schematic of a bottom hole assembly 2 including from top to bottom; a control module 80, a holding tool 90, a pressure chamber 20, a fluid-powered motor 40, a gearbox 100 and a cutting head 60.
[0226] FIG. 22A is showing a cutting tool 10 including a gearbox 100.
[0227] FIG. 22B is a cross-section of FIG. 22A along line N-N in FIG. 22A. The gearbox 100 is secured to the lower end of pressure chamber 20 by a gearbox housing 101. A gas-driven rotatable motor 40 includes an output pinion 69 which powers the gearbox. The gearbox includes an output shaft 105 which powers the cutting head 60. The gearbox housing 101 includes circumferential gearbox slots 102 which are aligned with the fluid passages 43. A solid shaft 96 is sealed to the lower end of the pressure chamber 20 with seal 97. The solid shaft 96 is disposed through the fluid-powered motor 40 and the gearbox 100 and secures the cutting head 60 to the gearbox output shaft 105.
[0228] FIGS. 23A and 23B are showing detailed views of the gearbox 100, including gearbox housing 100, ring gear 104, planetary gears 103, circumferential gearbox slots 102 and gearbox output shaft 105. The gearbox 100 may function to reduce or increase the rotational speed of the cutting head 60 relative to the gas-driven rotatable motor 40.
[0229] FIG. 24 is showing a schematic of a bottom hole assembly 2 including from top to bottom; a control module 80, a holding tool 90, a pressure chamber 20, a fluid-powered motor 40 and a cutting head 60. The components of the bottom hole assembly are the same as in FIG. 21 except that the bottom hole assembly 2 in FIG. 24 does not include a gearbox 100.
[0230] In FIG. 25A it is shown the bottom hole assembly 2 which is deployed by a wireline 5 inside a tubular 6 to a desired location within a subterranean well 4 with its cutters 62 in retracted position, i.e. an initial position within a circumferential envelope of the cutting head 60.
[0231] In FIG. 25B is shown the bottom hole assembly 2 at the same location in a subterranean well 4 with, the holding linkages 91 of holding tool 90 actuated to engage holding pads 92 to the inner surface 9 of tubular 6.
[0232] In FIG. 25C is shown the bottom hole assembly 2 at the same location in a subterranean well 4 with, the gas-driven rotatable motor 40 activated in a rotational motion, as indicated by the arrow A.
[0233] In FIG. 25D is shown the bottom hole assembly 2 at the same location in a subterranean well 4 with the gas-driven rotatable motor 40 and cutting head 60 in a rotational motion (as indicated by arrows A and B) causing the cutters 62 to be extended to cut the tubular 6, i.e. the cutters are outside a circumferential envelope of the cutting head 60.
[0234] In FIG. 25E is shown the bottom hole assembly 2 at the same location in a subterranean well 4 with gas-driven rotatable motor 40 and the cutting head 60 in a rotational motion causing the cutters 62 severing the tubular 6.
[0235] In FIG. 25F is shown the bottom hole assembly 2 at the same location in a subterranean well 4, the tubular 6 has been severed by a cut 11. The rotational motion of the gas-driven rotatable motor 40 and the cutting head 60 has stopped and the cutters 62 are in a retracted position, i.e. in an initial position within a circumferential envelope of the cutting head 60. The holding linkages 91 of holding tool 90 are de-actuated to disengage holding pads 92 from the inner surface 9 of tubular 6.
[0236] FIG. 26 is showing signal schematic for a bottom hole assembly 2 including a cutting tool 10 where an example of operation of the signal schematic will be described in the following in combination with some of the components described above. A propellant 28 is used to generate pressurized fluid 115 in a pressure chamber 20 as the fluid source. An ignitor 21 is in communication with, and may be controlled by, the controller 81. For possibly selectively controlling the flow of pressurized fluid 115 to the gas-driven rotatable motor 40, one or more valve actuators 52 to operate valve 49 may be in communication with, and may be controlled by, the controller 81 for opening and closing the delivery of pressurized fluid 115 to the gas-driven rotatable motor 40, for example. A pressure sensor 109 may be in communication with the controller 81 such that when pressure in a pressure chamber 20 is reduced below a predetermined pressure, the valve actuators 52 may be actuated to close the valve 49 or the cutting operation terminated. A speed sensor 108 may be in communication with the controller 81 as means to detect when a cut 11 in a downhole tubular 6 is complete. For example, while the cutting of a tubular 6 is in process, the speed sensor will communicate the rotational speed of the gas-driven rotatable motor 40 and possibly the cutting head 60 to the controller 81. When the cut 11 is complete, and the speed sensor detects an increase or a change in rotational speed of the gas-driven rotatable motor 40 and/or the cutting head 60, the controller 81 may function to stop the delivery of pressurized fluid 115 to the gas-driven rotatable motor 40 or end the cutting operation. A surface system/computing system 22 may be used to send signals from surface to the downhole controller 81 during a deployment of the bottom hole assembly 2. Additionally, the computing system may be used to pre-program the controller 81 prior to deployment in an operation where surface communication to and from the deployed bottom hole assembly 2 is unavailable. The controller 81 may be an analog circuit or digital processor, such as an application specific integrated circuit (ASIC) or array of field-programmable gate arrays (FPGAs). Accordingly, embodiments may implement any one or more aspects of control logic in the controller 81 that is on-board the cutting tool 10 or in a computing system/surface system 22 that is in data communication with the controller 81. The computing system/surface system 22 may be located at the surface to provide a user-interface for monitoring and controlling the operation of the cutting tool 10 and may be in data communication with the controller 81 over the wireline 5. The control module 80 may receive electrical power through a wireline 5 but it may receive some or all its electrical power from a battery within the bottom hole assembly 2. When receiving electrical power, the controller 81 may activate the ignitor 21 or valve actuator 52 or other electromechanical or electrohydraulic components within the bottom hole assembly 2 based on a timer, or other set parameters and inputs from within the bottom hole assembly 2, the surrounding well environment or by input from the surface system 22.
[0237] FIG. 27A is showing a view of a cutting tool 10 including a pressure chamber 20, a gas-driven rotatable motor 40 and cutting head 60. Gas-driven rotatable motor 40 is disposed to rotate relative to pressure chamber 20 on gas-driven rotatable motor shaft 41 and about bearings 26. Rotary seals 25 facilitate fluid communication from the pressure chamber 20 to the gas-driven rotatable motor 40.
[0238] FIG. 27B is a cross-section of FIG. 27A along line O-O showing the fluid passage port 30 from the pressure chamber 20 being in fluid communication with the fluid passages 43, each comprising a first portion 37 and a second portion 38.
[0239] In FIG. 28 it is shown an enlarged section of details in the area marked P in FIG. 27A, which shows that fluid passage port 30 from pressure chamber 20 having fluid communication through fluid passage hole 32 with annular space 33 caused by shaft recess 39. When the pressurized fluid 115 exits from the pressure chamber 20 and passes into annular space 33 it flows into the fluid passages 43, showing that the pressure chamber 20 is fluidically connected to gas-driven rotatable fluid passages 43 which are disposed to exhaust gas, thereby creating rotational motion of the gas-driven rotatable motor 40.
[0240] FIG. 29 shows a component of cutting tool 10, a pressure chamber 20, equipped with propellant holder 29 at the top. At the bottom of pressure chamber 20, pressurized fluid 115 can exit through fluid passage port 30 into fluid passage hole 32. Below pressure chamber 20 is shown gas-driven rotatable motor shaft 41, shaft recess 39 in detail and threaded end 42 of fluid-powered motor shaft 41.
[0241] FIG. 30 is showing a cross-section of a cutting tool 10 including a gearbox 100. The sun gear 106 of gearbox 100 is integral with through-shaft 107 which is secured to the lower end of a pressure chamber 20 and the lower end of bottom nut 63. Gearbox housing 101 is integral with ring gear 104 and secured to gas-driven rotatable motor 40. The ring gear 104 is thereby driven by rotation of the gas-driven rotatable motor 40 which in turn drives planetary gears 103 and planetary carrier 110 connected thereto. Gearbox output shaft 105 is integral to planetary carrier 110 and coupled to cutting head 60, such that rotational energy may be transferred from output shaft 105 to cutting head 60.
[0242] FIG. 31 is showing a view of a portion of a cutting tool 10 including a pressure chamber 20, a gas-driven rotatable motor 40 and a gas-driven rotatable motor biasing mechanism, a spring-loaded clutch 111. Gas-driven rotatable motor 40 is disposed to rotate relative to pressure chamber 20 on gas-driven rotatable motor shaft 41 and about bearings 26. Rotary seals 24 and 25 facilitate pressurized gas 115 communication from the pressure chamber 20 to the gas-driven rotatable motor 40.
[0243] Pressurized fluid 115 travels into fluid passage port 30 and exits through fluid passage holes 32 and into annular space 33. From annular space 33, fluid is exhausted from the cutting tool via, first portion 37 and second portion 38 of fluid passages 43. At the same time, pressurized fluid 115 travels through lower bearing 26 and applies pressure to clutch plate 71 at interface 70. Clutch spring 72 applies a force to the clutch plate 71 and against spring nut 73 which is fixed to gas-driven rotatable motor shaft 41, and when the pressurized fluid 115 is at a pressure sufficient to overcome the spring force, i.e. at or above the gas-driven rotatable motor set-point pressure, the clutch plate 71 is disengaged from the gas-driven rotatable motor 40 allowing the exhausted fluid to generate a thrust and thereby rotate the gas-driven rotatable motor 40. When pressurized fluid 115 is at a pressure insufficient to overcome the spring force, i.e. at a pressure below the gas-driven rotatable motor set-point pressure, the clutch plate 71 is engaged to the gas-driven rotatable motor 40 and it does not rotate or is in the process of stopping rotation. The gas-driven rotatable motor 40 is integral with ring gear 104 of gearbox 100, while sun gear 106 is integral with gas-driven rotatable motor shaft 41, such that when the gas-driven rotatable motor 40 rotates, the planetary carrier 110 with gearbox output shaft 105 rotates. A cutting head (not shown) may be secured to the output shaft 105 to receive the rotational power from the shaft and for use in a downhole pipe cutting operation.
[0244] FIG. 32 is showing a view of a portion of a cutting tool 10 including a pressure chamber (not shown), a gas-driven rotatable motor 40 a gearbox 100 and a cutting head 60. As shown, FIG. 32 is a cross-section partial view of an embodiment of a cutting tool with pivoted arms and a pivoted arm biasing mechanism. Pressurized fluid 115 travels into fluid passage port 30 from the pressure chamber and into pivoted arm piston chamber 78 and applies pressure to piston 76. When pressurized fluid 115 is at a pressure sufficient to overcome the spring force of pivoted arm return spring 77, i.e. at or above the piston set-point pressure, one or more pivoted arms 75 with cutters 62 attached thereto, may be extended towards the pipe the cutting tool 10 is deployed within; and when the piston 76 is subject to a pressurized gas 115 below the piston set-point pressure, the one or more pivoted arms 75 are in the retracted position or in a process of retracting, and the cutters 62 are not in contact with the pipe.
[0245] FIG. 33 is a chart of pressure vs. time; schematically showing various pressure set-points, steps, and conditions, of the bottom hole assembly. Pressure is increasing on the Y-axis and Time in increasing on the X-axis. At step “A” the propellant is ignited while exposed to wellbore pressure (the lowest horizontal line) and the pressure in the pressure chamber is pressurizing (condition I). Near time “2”, the holding tool is activated, step “B”, when pressurized gas is at the holding tool set-point pressure (the middle of the three horizontal lines). The bottom hole assembly is secured to the tubing and the pressure chamber is further pressurizing (condition II). Near time “2.5” the gas-driven motor is activated, step “C”, upon reaching the gas-driven motor set-point pressure. The pressure chamber is further pressurizing, the bottom hole assembly is secured to the tubing and the gas-driven motor is rotating; the cutting tool cutting with a cutting head attached thereto (condition III). At time “3” peak pressure in the pressure chamber is reached. Once peak pressure is achieved, due to the continued exhausting of the pressurized gas from the bottom hole assembly, the pressure of the pressurized gas begins to reduce. The pressure chamber de-pressurizing, the bottom hole assembly is secured to the tubing and the gas-driven motor is rotating; the cutting tool cutting with a cutting head attached thereto (condition IV). The pressure in the pressure chamber then reached the gas-driven motor setpoint pressure just after time “4”, step “E”, and once the pressure falls below the gas-driven motor set-point pressure, the gas-driven motor is stopped or is then in the process of stopping to rotate. The bottom hole assembly is secured to the tubing and the pressure chamber is further de-pressurizing, (condition V). The pressure in the pressure chamber then reaches the holding tool setpoint pressure at time “5”, step “F”, and once the pressure falls below the holding tool set-point pressure, the holding tool is de-activated or is in the process of de-activated from engagement with the tubing. The bottom hole assembly is further de-pressurizing, (condition VI) and continues to do so until the pressure in the pressure chamber is equalized to the wellbore pressure at time “6”, step “G”, and indicated by the lowest horizontal line. It should be noted that the time references indicated in the chart are for illustration purposes only and not indication of actual time during the operation of the bottom hole assembly.
[0246] In the preceding description, various aspects of a bottom hole assembly according to the invention have been described with reference to the illustrative embodiments. However, this description is not intended to be construed in a limiting sense. Various modifications and variations of the illustrative embodiment, as well as other embodiments of the system, which are apparent to persons skilled in the art, are deemed to lie within the scope of the present invention as defined by the following claims.
