A device is disclosed for facilitating the transport of an apparatus along an upward or a downward directed conduit or borehole. The device and method may for example have application in transporting an apparatus through a drill string which is being used to drill and upward or a downward directed borehole.
In many mining and civil engineering activities it is necessary to transport an apparatus or tool along a conduit such as a drill string or a borehole. Non limiting examples of such apparatus or tool include: an inner core barrel for a core drill; a greasing tool; and, a data logging system. The conduit or borehole can extend with a positive, neutral or negative gravity gradient. A borehole with a positive gravity gradient is one in which a toe of the borehole is at a vertical depth greater than a collar of the borehole; whereas a borehole with a negative gravity gradient is one where the toe of the hole is vertically above the collar of the hole. A neutral gravity gradient borehole is one that extends horizontally. With reference to the horizontal plane the negative gravity gradient borehole is one that is inclined above the horizontal travelling from the collar to the toe; whereas the positive gravity gradient borehole is one that is inclined below the horizontal travelling from the collar to the toe.
When it is necessary to transport an apparatus down a positive gravity gradient borehole is often possible to rely on gravity to provide the motive force. However when the borehole holds a volume of water or other liquid the speed of transport can be substantially reduced due to the need for the liquid to in effect flow between the outer surface of the descending apparatus and the surface of the borehole.
Of course when transporting an apparatus up a negative gradient borehole one must provide a force which continually acts on the apparatus to transport it toward the toe of the borehole and against the action of gravity. This can be achieved by attaching a plug like adapter to an up hole end of the apparatus and subsequently pumping water into the borehole to push the apparatus up the borehole. However the same plug like adapter is generally not suitable for use with the positive gravity gradient borehole because it reduces fluid bypass when descending and substantially increases the time taken to deliver the apparatus to the toe.
In one aspect there is disclosed a device for facilitating the transport of an apparatus along an upward or downward directed conduit or bore hole comprising:
a body having an upper body portion and a lower body portion which are coupled together and movable axially relative to each other;
a fluid flow path internal of the body selectively enabling fluid to flow through the body;
a first valve system located at a first end of the internal fluid flow path, the first valve system being operable by a pressure differential between a region external of the body and the internal fluid flow path;
a second valve system located at second end of the internal fluid flow path, the second valve system being operable by relative movement between the upper body portion and lower body portion; and
one or more openings at an end of the body downstream of the first valve system through which fluid can flow or fluid pressure can be communicated to an apparatus being transported by the device.
In a second aspect there is disclosed a device for facilitating the transport of an apparatus along an upward or downward directed conduit or bore hole comprising:
a body having a stem, an upper body portion and a lower body portion wherein the upper and lower body portions are coupled together by and at opposite ends of the stem and the upper and lower body portions are movable axially relative to each other;
the stem forming a fluid flow path internal of the body selectively enabling fluid to flow through the body;
a first valve system located at a first end of the internal fluid flow path, the first valve system being operable by a pressure differential between a region external of the body and the internal fluid flow path;
a second valve system located at second end of the internal fluid flow path, the second valve system being operable by relative movement between the upper body portion and lower body portion; and
one or more openings at an end of the body downstream of the first valve system through which fluid can flow or fluid pressure can be communicated to an apparatus being transported by the device.
In one embodiment the second valve system comprises one or more radial ports, and the second valve system is arranged to close the one or more radial ports and the upper and lower body portions are moved relatively toward each other, and arranged to open the one or more radial ports when the upper and lower and lower body portions are moved relatively away from each other.
In one embodiment the second valve system comprises a sleeve coupled to the upper body portion and slidably retained within the second body portion, the sleeve movable to an open location where the sleeve uncovers the one or more radial ports to allow a flow of liquid there through, and a close location where the sleeve covers the one or more radial ports to prevent a flow of liquid there through.
In one embodiment the first valve system comprises a valve member and the valve seat and wherein when the pressure differential is at a first level the valve member seats on one side of the valve seat to close the first valve system and when the pressure differential is at a second level greater than the first level the valve member is arranged to pass through the valve seat to an opposite side to open the first valve system enabling fluid to flow through the first valve system toward the one or more openings at the end of the body downstream of the first valve system.
In one embodiment the device comprises a sealing mechanism removably connectable to the body and arranged to form a liquid seal between the device and a conduit or borehole through which the device travels.
In one embodiment the sealing mechanism is disposed on the body at location between the first valve system and the second valve system.
In one embodiment when the pressure differential is at the second level liquid upstream of the sealing mechanism is able to flow into the internal flow path by passing the sealing mechanism.
In one embodiment when the pressure differential is at the second level and the second valve system is closed liquid upstream of the sealing mechanism is able to flow through the internal flow path bypassing the sealing mechanism and flowing or communicating fluid pressure through the one or more openings at the end of the body downstream of the first valve system.
Notwithstanding any other forms which may fall within the scope of the device as set forth in the Summary, specific embodiments will now be described, by way of example only, with reference to the covering drawings in which:
In the following discussion of the device 10, irrespective of the gradient of the drill sting, the term “downstream direction” with reference to a direction from a collar of a borehole in which the drill string is located to the toe of the borehole in which the drill string is located. Thus for a drill string having a drill bit at one end and connected to a machine at an opposite end the downstream direction is a direction toward the drill bit. The term “upstream direction” is the direction from the toe of the borehole in which the drill string is located toward the collar of the borehole. Thus the upstream direction is a direction away from the drill bit. The term “downhole end” or “downstream end” means the end of the drill string having the drill bit; and the term “up hole end” or “upstream end” means the end of the drill string distant the drill bit.
The device 10 can operate as a seal that can be selectively bypassed. When the device 10 is in a pump-in mode or configuration (which is depicted if
The device 10 also has an injection or bypass mode (shown in
The device 10 has a body 13 on which is mounted a sealing mechanism 14. The sealing mechanism 14 years in the form of annular washers 16a, and 16b (hereinafter referred to in general as “washers 16”). The washers 16 are provided with circumferential skirts or flaps 17 that are able to inflate or otherwise deflect outwardly in responses to upstream fluid pressure.
The body 13 is formed from several major components which are coupled together. These components include a stem 18, an upper body portion 20 and a body portion 22 which are coupled together by the stem 18. The upper and lower body portions 20 and 22 are axially movable relative to each other. A spear point 23 is connected to the upper body portion 20. A downhole end of the lower body portion 22 is provided with an externally threaded boss 24 which, with reference to
The upper body 20 is formed with a plurality of radially extending first ports 26. The first ports 26 lead to an internal axial passage 28. The up hole end of the stem 18 is connected to the internal axial passage 28. A valve seat 30 is retained in the stem 18 at an end adjacent the upper body 20. The valve seat 30 is configured to seat a valve member in the form of a ball 32.
The stem 18 is formed with a central axial passage 34 that extends from the valve seat 30 to a location inside of the lower body 22. A circumferential shoulder 35 is formed about the stem 18 intermediate of its length. The washers 16 which form the sealing mechanism 14 are retained between the shoulder 35 and the upper body 20.
The downhole end of the stem 18 is connected to a sleeve 36. The sleeve 36 has an axial passage 38 and is able to slide axially within the body 22. A cap 40 couples the stem 18 and the sleeve 36 to the body 22. The cap 40 is formed with a central passage 42 through which the stem 18 passes. The passage 42 has an increased inner diameter portion 44 creating an internal shoulder 46. A ring 48 is retained between the cap 40 and the lower body 22. The function of the ring 48 is to assist in centralisation of the device 10 within the drill string 12. The ring 48 can be replaced by unscrewing the lower body 22 from the cap 40.
The body 22 is formed with a plurality of radially extending second ports 50. The ports 50 lead to a central passage 52. An internal shoulder 53 is formed in the body 22 on a downhole side of the ports 50. A wall 54 extends across a downhole end of the passage 52. The wall 54 is formed with one or more, and in this case a plurality, of openings 56.
The device 10 has an internal flow path 58 (shown as a dashed line). Internal flow path 58 when opened allows fluid to bypass the sealing mechanism 14. The combination of the valve seat 30 and the valve ball 32 forms a first valve system 60. The first valve system 60 is located at a first end of the internal fluid flow path 58 and is operable by a pressure differential between a region external of the body 10 and the internal fluid flow path 58. For example, if the fluid pressure acting on the valve ball 32 from within the body 13 in the fluid flow path 58 is greater than the pressure of fluid acting on the valve ball 32 in a region between an outside of the body 13 on the inside of the drill string 12, then the first valve system 60 will be open with the ball 32 located off the seat 30. More generally, when the pressure differential is at a first level the valve member/ball 32 seats on the valve seat 30 to close the first valve system 60 and when the pressure differential is at a second level greater than the first level the valve member 34 is arranged to pass through the valve seat 30 to open the first valve system 60 enabling fluid to flow through the first valve system toward the openings 56.
The device 10 has a pump in mode or configuration shown in
The device 10 also has a freefall mode which shown in
The device 10 can be switched between the pump-in mode (
The operation of the device 10 will now be described in the context of being attached to the apparatus A which holds a supply of a flowable substance (not shown) and is being transported to a downhole end of the drill string 12 to inject the flowable substance in the region of a toe of a negative gravity gradient borehole.
Pump-in Mode. The ensemble of the device 10 with the attached apparatus A is inserted into an up hole end of the drill string 12. The device 10 is initially in the freefall mode shown in
A fluid such as water is now pumped into the drill string 12. The sealing mechanism 14 forms a substantial fluid seal against the inner circumferential surface of the drill string 12. The pressure of the water inflates the side skirts 17 enhancing the sealing effect against the inner circumferential surface of the drill string 12. While the water is unable to pass the sealing mechanism 14 it is able to flow into the first ports 26. The resultant water pressure pushes the valve ball 32 onto the valve seat 30 thereby closing the internal flow path 58. Additionally, if not already in this configuration, the water pressure will cause the stem 18 and sleeve 36 to slide in a downhole direction relative to the body 22 so that the sleeve 36 abuts the shoulder 53 closing the ports 50 for example as shown in
During this time the pressure of the water is maintained below the threshold pressure required to cause the valve 60 to open. Therefore the net effect of the water pressure is to push the device 10 and thus the connected apparatus A along within the drill string 12 toward the down hole end of the drill string 12 and the toe of the corresponding borehole. During this period no water or water pressure can be communicated through the openings 56 into the apparatus A.
Eventually a downhole end of the apparatus A, or alternately a landing shoulder (not shown) of the device 10 lands on a landing ring or other device (for example a drill bit) attached to or located within the drill string 12 halting any further travel of the device 10 and apparatus A down the drill string 12. This will be typically indicated to a drill rig operator by a decrease in flow rate of water into the drill string 12. The drill rig operator may now increase the water pressure to above the threshold pressure at which the valve mechanism 60 opens. At this pressure the valve ball 32 is forced or popped through the valve seat 30 and can travel through the body 13 landing on the wall 54. The configuration of the device 10 when in this condition is shown in
The internal flow path 58 is now open and water W (or other liquids such as drilling mud) is able to flow through the device 10 bypassing the sealing mechanism 14 and into an adjacent end of the A via the openings 56. Accordingly the fluid pressure can now operate the apparatus A to perform its intended function which in this example is to inject the flowable substance into the borehole.
Once a downhole operation has been performed by the apparatus A transported by the device 10 the ensemble can be retrieved by progressively reducing the fluid pressure allowing gravity to cause the device 10 and apparatus A to float down the drill string 12.
There are several retrieval scenarios available for the device 10 depending on the gradient of the borehole/drill string 12. If the gradient is positive to zero, i.e. for boreholes that extend vertically downwardly to those which are horizontal or include horizontal portions, retrieval is via a wire line and overshot that connect to the spear point 23. Reeling in the wireline will cause the stem 18 and the sleeve 36 to slide axially in the up hole direction within the cap 40 until it engages the internal shoulder 46. When this occurs the sleeve 36 uncovers the second ports 50 thereby effectively opening the second valve system 51. This configuration is shown in
A further optional feature that may be incorporated in the device 10 when used in negative gravity gradient boreholes is a latch system 70 an example of which is depicted in
The latch system 70 will interact with a latching shoulder (not shown) formed on an internal surface of the drill string 12. The latch system 70 may comprise a plurality of sprung latch dogs 72. The latching shoulder is located so that when the apparatus A engages a stop mechanism such as a drill bit at the downhole end of the string 12 the latch dogs 72 of the latch system 70 latches onto the latching shoulder. This has the effect of latching the entirety of the device 10 and the apparatus A at the downhole end of the drill string 12. Therefore if water pressure is reduced or shut off there is no risk of the device 10 and apparatus A sliding back down the drill string 12 in an uncontrolled manner without the knowledge of the drill operator which could otherwise cause significant damage to equipment and injury or death to an operator. A non-limiting example of one type of latching system 70 that can be used in this application is described in international publication number WO 2010096860 the contents of which is incorporated herein by way of reference.
When a latching system 70 is incorporated in the device 10 then an overshot on a wireline will be required to be pumped in drill string 12 to engage the spear point 140 to release the latching system enabling the retrieval of the device 10/apparatus A.
Free Fall Mode. The free fall mode shown in
Rapid Descent Mode. The rapid descent mode as shown in
The device 10 is described with reference to connection to and use with an apparatus A for delivering and injecting a flowable substance into a borehole. However the device 10 is not limited to such use. Rather the device 10 can be used to assist in the delivery and transport of in a downhole tool is equipment particularly when required to travel in a shallow or negative gravity gradient hole.
In the claims which follow, and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word “comprise” and variations such as “comprises” or “comprising” are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the method and system as disclosed herein.
Number | Date | Country | Kind |
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2016904356 | Oct 2016 | AU | national |
This application is a continuation of application Ser. No. 16/344,102 filed on Apr. 23, 2019 entitled DEVICE FOR FACILITATING THE TRANSPORT OF AN APPARATUS ALONG AN UPWARD OR A DOWNWARD DIRECTED CONDUIT OR BOREHOLE which is a national stage filing under 35 U.S.C. Section 371 of Patent Cooperation Treaty Application serial no. PCT/AU2017/051183 having an international filing date of Oct. 26, 2017 and claiming priority of Australian patent application serial no. 2016904356 filed on Oct. 26, 2016, the disclosures of which are incorporated herein by reference.
Number | Date | Country | |
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Parent | 16344102 | Apr 2019 | US |
Child | 17196541 | US |