The present application is a U.S. National Stage patent application of International Patent Application No. PCT/US2013/026881, filed on Feb. 20, 2013, the benefit of which is claimed and the disclosure of which is incorporated herein by reference in its entirety.
The present invention relates generally to pressure responsive tools and, more specifically, to a pressure responsive downhole tool having an operating valve element that can remain open when annulus pressure is relieved.
Conventional tester valves utilize annulus pressure to operate a valve element, such as a ball valve, where application of predetermined annulus pressure can be utilized to open the valve element while reduction of the annulus pressure can be utilized to close the valve element. One drawback to such a system is that the valve element will not remain in an open position when the annulus pressure is reduced. For certain downhole activities, however, it is desirable to hold a tester valve in such a “lock open” configuration once annulus pressure is reduced.
More recent tester valves employ mechanisms to lock open the valve element when annulus pressure is reduced. Specifically, a movable slotted sleeve is utilized to index the position of an actuation arm so that the actuation arm will not force the valve element to a closed position when the annulus pressure is relieved. While such systems may be functionally satisfactory, the systems utilized to apply the motivation force to move the slotted sleeve are complicated and often require operating pressures to activate the lock open feature that are significantly higher than the normal annulus pressure. For example, normal operating annulus pressures utilized with tester valves are typically in the range of 1200 psi, whereas annulus pressures of 2500 psi are required to operate lock-open features of certain prior art tester valves. Persons of ordinary skill in the art will appreciate that use of such high pressures with systems as described can adversely impact other components of the downhole mechanism, such as rupture disks, or system components with lower pressure ratings.
Accordingly, in view of the foregoing, there is a need in the art for a tester valve that utilizes lower annulus pressures to locked open a valve element. Such a tester valve would desirably utilize the same approximate annulus pressure to both operate the valve element and to lock open the valve element as desired.
Illustrative embodiments and related methodologies of the present invention are described below as they might be employed in a pressure responsive downhole tool having a lock open feature for a valve element that employs the same approximate annulus pressure utilized to open and close the valve element. In the interest of clarity, not all features of an actual implementation or methodology are described in this specification. Also, the “exemplary” embodiments described herein refer to examples of the present invention. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. Further aspects and advantages of the various embodiments and related methodologies of the invention will become apparent from consideration of the following description and drawings.
As described herein, exemplary embodiments of the present invention are directed to a pressure responsive downhole tool having a power piston pressure relief valve that may be selectively deactivated and activated to allow operations to be conducted using the tool. The pressure responsive downhole tool may be a variety of tools, such as, for example, a tester valve as described in U.S. Pat. No. 5,558,162, entitled “MECHANICAL LOCKOUT FOR PRESSURE RESPONSIVE DOWNHOLE TOOL,” also owned by the Assignee of the present invention, Halliburton Energy Services, Co. of Houston, Tex., the disclosure of which is hereby incorporated by reference in its entirety. As such, the inventive features described herein will be discussed in relation to a drill stem tester (“DST”) valve. However, those ordinarily skilled in the art having the benefit of this disclosure realize the present invention may be applied to any variety of pressure responsive tools.
As further described herein, exemplary embodiments of the pressure responsive tool includes a bidirectional collet system utilized in conjunction with pressurized fluids to operate a ball valve system as described herein. In embodiments utilized within a drill stem tester valve, during downhole deployment of the tool, the ball valve system is in the open position. Once the tool has been positioned within a wellbore, the annulus pressure within the wellbore is raised. As the annulus pressure increases, the annulus pressure actuates an upper piston that is secured to an operating mandrel system and a bidirectional collet system. Movement of the upper piston under application of annular pressure causes the bi-directional collet system to engage a first shoulder defined on an internal static mandrel to temporarily inhibit continued movement of the piston. Once the applied annular pressure has reached a predetermined threshold, the bi-directional collet system disengages the first shoulder and translates across the shoulder, allowing the piston to continue to actuate. At this point, a lower portion of the operating mandrel system shifts relative to locking dogs carried by an upper portion of the operating mandrel system until the locking dogs radially engage the lower portion of the operating mandrel system, thereby securing the upper and lower portions of the operating mandrel system to one another. In conjunction with actuation of the piston, a fluid within a fluid chamber is pressurized to the annulus pressure. As the annulus pressure is thereafter slowly bled down, the pressurized fluid is maintained at an elevated pressure relative to the annulus pressure such that the pressurized fluid bearing on the upper piston urges the bi-directional collet system into engagement with a second shoulder defined on the internal static mandrel to temporarily inhibit movement of the piston. Once the pressure differential across the upper piston between the reduced annulus pressure and the pressurized fluid reaches a predetermined threshold, the bi-directional collet system disengages the second shoulder and translates back across the shoulder, allowing the piston to continue to actuate. This actuation causes the operating mandrel system attached to the piston to drive the ball valve system from an open to a closed position. An adjustable metering mechanism maintains the elevated pressure of the pressurized fluid even as the annulus fluid is bled down.
To the extent it is desired to have the ball valve system remain open once the annulus pressure is bled down, then the annulus pressure is increased sufficiently to drive the collet across the first shoulder. Thereafter, the annulus pressure is bled down quickly. In such case, the collet lands on the second shoulder as described above. However, due to the expedited pressure annulus pressure change, the fluid within the fluid chamber cannot be sufficiently pressurized to overcome the force needed to drive the collet back across the second shoulder as described above. In other words, the necessary pressure differential cannot be achieved. As such, the collet remains seated on the second shoulder and the ball valve system remains open even though the annulus pressure has been bled down.
Referring now to
Referring now to
The valve housing section 18 generally includes an upper seat holder mandrel 54 threadingly connected to upper adapter 16. Upper seat holder mandrel 54 includes shoulder 62 against which an upper valve seat assembly 68 is received. An operating element, such as a spherical ball valve 70, is carried by valve housing 18. In particular, spherical ball valve 70 is bounded by upper valve seat assembly 68 as well as a lower valve seat assembly 74 which is carried a lower seat holder mandrel 76. A biasing member 82, such as a Belleville spring, for example, is located below lower seat 74 to provide the necessary resilient clamping of the ball valve 70 between seat assemblies 68 and 74. Ball valve 70 has a bore 72 disposed therethrough. In
Disposed below valve housing section 18 is connector section 24. Connector section 24 generally includes an operating mandrel assembly 92 having an upper operating mandrel portion 94 disposed to slide axially within housing 12 and a lower operating mandrel portion 98 disposed to slide axially relative to upper operating mandrel portion 94 as described below. Upper operating mandrel portion 94 engages an actuating arm 86, which actuating arm 86 includes an actuating lug 88 disposed thereon. Actuating lug 88 engages an eccentric bore 90 defined in ball valve 70 so that the ball valve 70 may be rotated between an open position (shown in
Upper operating mandrel portion 94 carries at least one and preferably a plurality of locking dogs 112, each of which is disposed adjacent a radial window 114 in upper operating mandrel portion 94 and biased radially inward by a biasing element 116, such as annular springs 116, to urge the locking dog 112 against lower operating mandrel portion 98. Lower operating mandrel portion 98 is closely slidably received within a bore 119 of upper operating mandrel portion 94.
Lower operating mandrel portion 98 carries an annular radial outer groove 118. Lower operating mandrel portion 98 is disposed to slide freely relative to upper operating mandrel portion 94 until locking dogs 112 are received within annular groove 118, thereby securing lower operating mandrel portion 98 to upper operating mandrel portion 94. Once locked together, actuation of lower operating mandrel portion 98 will result in actuation of upper operating mandrel portion 94, which in turn actuates actuating arm 86 so as to cause rotation of ball 70. As will be appreciated, therefore, actuation of lower operating mandrel portion 98 can be utilized to open and close ball valve 70.
Ball valve assembly section 18 and operating mandrel assembly 92 are seen in
Disposed below connector section 24 is ported nipple section 20, as best seen in
In this regard, disposed below ported nipple section 20 is upper gas chamber section 26, which includes upper gas chamber 176. Upper gas chamber section 26, in turn, is adjacent gas nipple section 28, which separates upper gas chamber section 26 from a lower gas chamber section 30, which includes a lower gas chamber 182. Gas nipple section 28 includes a gas port mandrel 180 having a gas nipple 186 in fluid communication with the upper and lower gas chambers 176, 182 by way of one or more flow passages defined within gas port mandrel 180 which also function to fluidly communicate upper chamber 176 with lower chamber 182. Although chambers 176 and 182 can be filled with any fluid, in certain preferred embodiments, chambers 176 and 182 are filled with nitrogen gas that can be pressurized as desired. A gas filler valve 183 (shown in
As best shown in
Actuating piston 136 serves to isolate well fluid, e.g., mud, entering port 132 and disposed within mud chamber 130 from the fluid, e.g., gas, contained in upper gas chamber 176. Actuating piston 136 is connected at threads 124 to lower operating mandrel portion 98. Hence, actuation of piston 136 by virtue of a pressure differential across piston 136 between the mud in mud chamber 130 and the gas in upper gas chamber 176 results in actuation of operating mandrel assembly 92 and ball valve 70.
Actuating piston 136 is slidingly disposed around an elongated static mandrel 178 that generally extends within bore 14 from approximate ported nipple section 20, through upper gas chamber section 26 and is secured adjacent gas nipple section 28 by gas port mandrel 180. Static mandrel 178 carries a radially outward extending flange 156 having a lower tapered shoulder 158 and an upper tapered shoulder 160 defined thereon.
Referring now to
In a first position, which may include the initial run-in position, as seen in
Referring to
Disposed below lower gas chamber section 30 is fluid metering mechanism section 32, as best seen in
Referring now to
Referring to
As understood in the art, multi-range metering mechanism 194 and the various passages and components contained therein can generally be described as a retarding mechanism disposed in the second pressure conducting passage system 238 for delaying communication of a sufficient portion of a change in well annulus pressure to the lower side 135 of piston 136 for a sufficient amount of time to allow a pressure differential on the lower side 135 of actuating piston 136 to move the actuating piston 136 upwardly relative to housing 12. Retarding mechanism also functions to maintain a sufficient portion of a change in well annulus pressure within the second pressure conducting passage and permit the differential in pressures between the first and second pressure conducting passages to balance.
Moreover, ball valve 70 can generally be referred to as an operating element operably associated with actuating piston 136 for movement with piston 136 between a first closed position and a second open position. However, in other exemplary embodiments, the first position may be open, while the second position may be closed. Those ordinarily skilled in the art having the benefit of this disclosure will realize that this and a variety of other alterations may be embodied within annular pressure responsive tool 10 without departing from the spirit and scope of the present invention.
Now that the various exemplary components of annular pressure responsive tool 10 have been described, an exemplary operation conducted using annular pressure responsive tool 10 will now be described with reference to
To describe an exemplary operation in more detail, annular pressure responsive tool 10 is made up, deployed downhole and positioned at a desired location. After annular pressure responsive tool 10 has been positioned at the desired location, a pressure increase is imposed upon the well annulus so that the annulus pressure of the mud around housing 12 is raised to a first desired pressure above hydrostatic. As will be appreciated, the rate at which the annulus pressure is increased and decreased (or bled off) can be utilized to drive tool 10 to either a first configuration in which ball valve 70 remains open when pressure is decreased or a second configuration in which ball valve 70 closes with pressure decrease. If annulus pressure is more slowly increased, gas chambers 176, 182 will retain or store the increased annulus pressure, which can subsequently be utilized to drive ball valve 70 to a close position. Conversely, if the annulus pressure is more rapidly increased and rapidly decreased, there is not sufficient time to transfer and store the pressure increase in gas chambers 176, 182, and as such, the result will be ball valve 70 remaining open upon the decrease in annulus pressure. Thus, a first rate of increase may be used for one function and a second rate of increase, different from the first, may be used for a different function.
With respect to storage of annulus pressure in gas chambers 176, 182, annulus pressure is transmitted into mud chamber 130 through port 132 and along the first pressure conducting passage 236 to exert annulus fluid pressure upon actuating piston 136 to move actuating piston 136 downward, compressing the gas within upper gas chamber 176. As the actuating piston 136 compresses the gas within upper gas chamber 176, the annulus fluid pressure is transmitted to the gas within gas chamber 176. Likewise, being in fluid communication with lower gas chamber 182, the pressure of the gas in upper chamber 176 is transmitted to the gas in lower gas chamber 182. As such, the pressure increase within the first pressure conducting passage 236, following downward movement of the piston 136, is stored with the nitrogen chambers 176 and 182 via compression of nitrogen gas contained within. An offsetting amount of fluid pressure is likewise transmitted upward along the second pressure conducting passage 238 through port 214 at the same time that it is transmitted downward along the first pressure conducting passage 236 through port 132. A slow increase in pressure permits the increased annulus pressure to be transmitted to and stored in chambers 176, 182 by virtue of both the first and second pressure conducting passages 236, 238. In such case, annulus pressure at port 214 is transmitted through oil chamber 210 to lower gas chamber 182. In contrast, a more rapid increase in pressure does not permit sufficient time for the annulus pressure to be transmitted along the second pressure conducting passage 238. Thus, while piston 136 may be driven to compress the gas in upper chamber 176 via upper pressure conducing passage 236 with a more rapid increase in annulus pressure, because there is not a corresponding application of annulus pressure from second conducting passage 238, the increased annulus pressure will not be retained by the gas chambers.
Notwithstanding the foregoing, in a first position, which may include the initial run-in position, as seen in
As annulus pressure is decreased or bled down once locking dogs 112 are engaged, if there is not sufficient pressure stored in gas chamber 176, collet finger 166 will shift relative to static mandrel 178 until shoulder 170 of collet head 168 engages second flange shoulder 158 of flange 156. Without sufficient application of pressure from chamber 176 to overcome the friction force between shoulder 170 of collet head 168 and second flange shoulder 158, collet finger 166 will not disengage the second shoulder 158 and translate across flange 156. Rather, additional upward travel of piston 136 will be stopped. Since lower operating mandrel portion 98 is fixed to piston 136 and upper operating mandrel portion 94 is secured to lower operating mandrel portion 98 by virtue of locking dogs 112, the actuating arm 86 attached to upper operating mandrel portion 94 and used to close ball valve 70 is not actuated. As such, ball valve 70 remains open with further bleed down of annulus pressure, thereby.
In contrast, if gas chamber 176 has sufficient pressure stored therein, collet finger 166 will disengage the second shoulder 158 and collet head 168 will translate across flange 156. Thereafter, pressure applied to piston 136 from gas chamber 176 will continue to urge piston 136 to shift upward relative to static mandrel 178. By virtue of the operating mandrel assembly 72 which is attached to both piston 136 and actuating arm 86, actuating arm 86 will be driven upward, thereby causing ball valve 70 to close.
The retarding function of the multi-range metering mechanism 194 is used to delay the increase in well annulus pressure from being communicated from oil chamber 210. As a result of the delay, the pressure within the first pressure conducting passage 236 will be greater than that within the second pressure conducting passage 238 during the delay. Eventually, the pressure differential between the first and second pressure conducting passages 236, 238 will become relatively balanced after a period of time.
When it is desired to close ball valve 70, annulus pressure may be reduced to hydrostatic causing a reverse pressure differential within both the first and second pressure conducting passages 236 and 238 from the stored pressure within the nitrogen chambers 176 and 182. Metering mechanism 194 delays transmittal of the pressure differential downward within the second pressure conducting passage 238, thereby maintaining an increased level of pressure within the upper portions of the second pressure conducting passage 238. The pressure differential upward within first pressure conducting passage 236 urges collet head 168 upwardly across flange 156. As piston 136 moves upwardly, the upward motion is transmitted to actuating arm 86, and ball valve 70 is moved to its closed position.
Thus, it will be appreciated that a rapid increase in annulus pressure will not result in sufficient pressure build up and storage in gas chamber 176 to overcome the “lock-open” force applied by collet fingers 166 to flange 156 because the multi-range metering mechanism 194 delays transmission of pressure necessary to allow pressure build up and storage in gas chamber 176. As such, ball valve 70 will remain open. It is only when annulus pressure is permitted to be transferred and stored in gas chamber 176, through a less rapid increase in annulus pressure over a more extended period of time, that the retained pressure in gas chamber 176 is sufficient to dislodge collet head 168 from flange 156, permitting continued movement of piston 136 so as to drive ball valve 70 to a closed position. In other words, increasing and/or decreasing the annulus pressure at a first rate will result in configuration of the tool to one state, while increasing and/or decreasing the annulus pressure at a second rate, different from the first rate will result in configuration of the tool to a different state, even as the pressure changes are substantially within the same range.
Accordingly, through use of the present invention, ball valve 70 can be locked open utilizing only the normal increase in annulus pressure otherwise utilized to simply open and close ball valve 70, thereby eliminating the need for elevated annulus pressures required for lock open features of the prior art. In certain preferred embodiments, the normal annulus operating pressure is in a range below the pressure at which rupture disks or other pressure devices may be activated. In certain preferred embodiments, the normal annulus operating pressure is around 1200 psi. Likewise, while particular first and second rates for annulus pressure application and/or release depend on the operating environment of the tool, in one embodiment, a first rate may be 20 psi/second while a second rate may be 2 psi/second.
The foregoing disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. Further, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the apparatus in use or operation in addition to the orientation depicted in the figures. For example, if the apparatus in the figures is turned over, elements described as being “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly.
Although various embodiments and methodologies have been shown and described, the invention is not limited to such embodiments and methodologies and will be understood to include all modifications and variations as would be apparent to one skilled in the art. Therefore, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
Filing Document | Filing Date | Country | Kind |
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PCT/US2013/026881 | 2/20/2013 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
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WO2014/130024 | 8/28/2014 | WO | A |
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3533430 | Fredd | Oct 1970 | A |
4125165 | Helmus | Nov 1978 | A |
4489786 | Beck | Dec 1984 | A |
4537258 | Beck | Aug 1985 | A |
4736798 | Zunkel | Apr 1988 | A |
4979568 | Spencer, III | Dec 1990 | A |
5209303 | Barrington | May 1993 | A |
5240072 | Schultz et al. | Aug 1993 | A |
5558162 | Manke et al. | Sep 1996 | A |
5984014 | Poullard et al. | Nov 1999 | A |
Entry |
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International Search Report and the Written Opinion of the International Searching Authority, or the Declaration, dated Oct. 25, 2013, PCT/US2013/026881, 11 pages, ISA/KR. |
Number | Date | Country | |
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20150330184 A1 | Nov 2015 | US |