AU2013204256A1

AU2013204256A1 - Improved Diverter Valve

Info

Publication number: AU2013204256A1
Application number: AU2013204256A
Authority: AU
Inventors: Jim Lawson HUGHES; Dale Parker
Original assignee: HP WELLHEAD SOLUTIONS Pty Ltd
Current assignee: HP WELLHEAD SOLUTIONS Pty Ltd
Priority date: 2012-10-11
Filing date: 2013-04-12
Publication date: 2014-05-01
Also published as: WO2014056044A1

Abstract

A diverter valve 300 for a well comprises a valve body 301 including a passage 305 through which a fluid flowing from the well is able to flow. At least one outlet 306 is connected to the passage 305 so that the fluid flowing through the passage 305 is able to be diverted to flow from the passage 305 and out of the valve body 301 through each outlet 306. A piston 309 is moveable along the passage 305 so as to control the flow of the fluid through each outlet. - N328 327-- : .......... 306 ------ 308

Description

1 IMPROVED DIVERTER VALVE FIELD OF THE INVENTION [0001] The present invention relates generally to valve apparatus for controlling fluid flowing from a well. [0002] Although the present invention will be described with particular reference to being used to control the flow of crude oil and/or natural gas from a subsea well, it will be appreciated that it is not necessarily limited to this particular use. BACKGROUND ART [0003] A blowout in the context of well drilling is the uncontrolled release of crude oil and/or natural gas from an oil well or gas well after pressure control systems have failed. [0004] There have recently been a number of significant oil well blowouts. On 21 August 2009 the West atlas oil rig was involved in a blowout that occurred in the Timor Sea off the coast of Western Australia. Another blowout which resulted in the destruction and sinking of the Deepwater Horizon oil rig occurred in the Gulf of Mexico on 20 April 2010. [0005] Both the Timor Sea blowout and the Gulf of Mexico blowout resulted in the uncontrolled release of large quantities of crude oil and natural gas into the surrounding environment. The release of this crude oil and natural gas has been quite harmful to the surrounding environments as well as to the wildlife inhabiting those environments. [0006] When drilling a well, a large specialised valve called a "blowout preventer" or "BOP" is normally used to cope with extreme erratic pressures and uncontrolled flow (formation kick) emanating from a well reservoir, and for preventing well blowouts. In addition to controlling the downhole pressure and the flow of oil and gas, blowout preventers are intended to prevent tubing (e.g. drill pipe and well casing), tools and drilling fluid from being blown out of the wellbore when a blowout threatens. Blowout preventers are critical to the safety of crew, rig, and the environment, and to the monitoring and maintenance of well integrity. Consequently, blowout preventers are intended to be fail-safe devices.

2 [0007] Although blowout preventers are intended to be fail-safe devices, they nevertheless do occasionally fail. If a blowout preventer fails, it can be very difficult to regain control over the flow of oil and/or gas from the well. During the period that control is lost, a large quantity of oil and/or gas from the well may flow into the surrounding environment. [0008] Even if a blowout preventer successfully prevents a blowout from occurring, the sudden increase in pressure in the well that is caused by the operation of the blowout preventer can damage the well and also the geological formation in which the well has been drilled. In some cases, the damage to the well and the formation can be severe enough that oil and/or gas is/are able to escape from the well and flow into the formation. The escaped oil and/or gas may then find its way into the environment through geological fissures and the like. [0009] Our International Patent Publication No. WO 2012/068624 Al, the contents of which are incorporated herein by reference in their entirety, discloses a valve apparatus that can be used to control the flow of oil and gas from a well in the event of a well blowout. The valve apparatus comprises a diverter valve that includes a valve body, and a valve member. The valve body includes a first passage that extends through the valve body, at least one second passage that extends through the valve body and laterally from the first passage. The valve body is connectable to the well so that a fluid flowing from the well is able to flow out of the valve body through the first passage. The valve member is insertable into the first passage and is moveable relative to the valve body by one or more hydraulic cylinders or other suitable lifting means located externally of the first passage so as to thereby control the flow of the fluid from the first passage into each second passage so that the flow of the fluid out of the valve body through each second passage can be controlled. The fluid that flows out of the valve body through each second passage can then be directed to flow into a tanker through pipes or hoses that are connected to each second passage. In this way, the valve apparatus is able to control the flow of fluid from the well and prevent it from escaping into the surrounding environment. [0010] A particular version of the valve apparatus disclosed in WO 2012/068624 Al includes a blowout preventer mounted on the valve member of 3 the diverter valve. The blowout preventer can be closed hydraulically so that the flow of fluid from the well can be completely shut off or so that fluid from the well can only flow out of the valve body through each second passage thereof. [0011] In some conditions it is desirable to have a diverting valve apparatus which has a more self-contained and streamlined valve body. [0012] It is against this background that the present invention has been developed. SUMMARY OF THE INVENTION [0013] It is an object of the present invention to overcome, or at least ameliorate, one or more of the deficiencies of the prior art mentioned above, or to provide the consumer with a useful or commercial choice. [0014] Other objects and advantages of the present invention will become apparent from the following description, taken in connection with the accompanying drawings, wherein, by way of illustration and example, a preferred embodiment of the present invention is disclosed. [0015] According to a first broad aspect of the present invention, there is provided a diverter valve for a well, the diverter valve comprising a valve body including a passage through which a fluid flowing from the well is able to flow, and at least one outlet connected to the passage so that the fluid flowing through the passage is able to be diverted to flow from the passage and out of the valve body through each outlet, and a piston moveable along the passage so as to control the flow of the fluid through each outlet. [0016] The provision of the piston which is moveable along the passage so as to control the flow of the fluid through each outlet is advantageous as it allows for the diverter valve to have a more self-contained and streamlined body, which is desirable in some conditions. [0017] The provision of the piston which is moveable along the passage so as to control the flow of the fluid through each outlet is also advantageous as it allows a blowout preventer or other equipment to be mounted on the valve body so that it is not necessary to raise and lower that other equipment when 4 operating the diverter valve by moving the piston along the passage of the valve body. [0018] Preferably, the passage of the valve body comprises a bore. [0019] Preferably, the valve body includes a piston chamber that receives the piston such that the piston divides the piston chamber into a lower section and an upper section, a first port connected to the lower section, and a second port connected to the upper section. [0020] Preferably, the valve body also comprises a lower body, and an upper body secured to the lower body. It is preferred that the piston chamber is defined by the lower body and the upper body. [0021] Preferably, the diverter valve also comprises a sleeve inserted into the passage and secured relative to the valve body, and a further piston chamber that receives the piston and that is defined by the sleeve and the valve body, and the valve body includes a third port connected to the further piston chamber. [0022] Preferably, the piston comprises a hollow piston. [0023] Preferably, the diverter valve also comprises an automatic fail-safe device/system that is able to operate the diverter valve in the event of the failure of other systems that are operable to control the diverter valve. [0024] Preferably, the valve body comprises a valve seat for the piston to rest against, and an inlet that extends to the valve seat so that a fluid injected through the inlet is able to clean the valve seat. [0025] Preferably, the diverter valve also comprises a choke and kill line that is able to communicate with the passage of the valve body. Preferably, the diverter valve also comprises a control valve that is connected to the choke and kill line. [0026] According to a second broad aspect of the present invention, there is provided a method of operating the diverter valve according to the first broad aspect of the present invention, the method comprising the steps of: allowing a fluid flowing from a well to flow through the passage of the valve body of the diverter valve; and 5 moving the piston of the diverter valve along the passage so as to control the flow of the fluid from the passage and out of the valve body through each outlet of the valve body. BRIEF DESCRIPTION OF THE DRAWINGS [0027] In order that the invention may be more fully understood and put into practice, a preferred embodiment thereof will now be described with reference to the accompanying drawings, in which: Figure 1 is an exploded view of a first diverter valve; Figure 2 is a diagrammatic cross-sectional view of the first diverter valve; Figure 3 is a diagrammatic cross-sectional view of a second diverter valve; and Figure 4 is a diagrammatic cross-sectional view of a third diverter valve. DESCRIPTION OF EMBODIMENTS [0028] Referring to figures 1 and 2, there is depicted a first diverter valve 300 for a subsea hydrocarbon well (not depicted) such as a crude oil and/or natural gas well. Diverter valve 300 includes a valve body 301 that includes a lower body 302 and an upper body 303. The upper body 303 is secured to the lower body by a H4 connector or latch locking system 304. [0029] Valve body 301 includes a passage provided by a bore 305 through which a hydrocarbon fluid flowing from the well is able to flow. A plurality of outlets 306 in the lower body 302 are connected to the bore 305 by a plurality of passages 307 that extend laterally from the bore 305 so that the fluid flowing through the bore 305 is able to be diverted to flow from the bore 305 and out of the valve body 301 through each outlet 306. [0030] A lower end 308 of the lower body 302 is machined or otherwise configured so that it is able to be connected to the well either directly or indirectly. In the case where the lower end 308 is to be connected to the well indirectly, the lower end 308 may be machined or otherwise configured to suit a range of third party connectors for securing blind shear rams, grab rams, or other 6 equipment to the lower body 302. The lower body 302 may be secured to the well such that the bore 305 is aligned with a bore of the well. [0031] Diverter valve 300 also includes a hollow piston 309 that is received by the bore 305 of the valve body 301. Piston 309 is slidingly moveable along the bore 305 of the valve body 301 so as to control the flow of the fluid through each outlet 306. [0032] The lower body 302 of the valve body 301 includes a valve seat 310, and a lower end 311 of the piston 309 is configured so that it is able to sealingly engage with the valve seat 310. [0033] Valve body 301 includes a piston chamber 312 that receives the piston 309 and that is defined by the lower body 302 and the upper body 303. The piston chamber 312 is sealed by a plurality of O-ring seals (not depicted) that are located in a plurality of grooves 313 in the lower body 302, and in a plurality of grooves 314 in the upper body 303. [0034] The piston 309 divides the piston chamber 312 into a lower section 315 and an upper section 316. The lower and upper sections 315, 316 of the piston chamber 312 are sealed from each other by a plurality of O-ring seals (not depicted) which are located in a plurality of grooves 317 in the piston 309. [0035] A first port 318 in the lower body 302 is connected to the lower section 315 of the piston chamber 312, and a second port 319 in the lower body 302 is connected to the upper section 316 of the piston chamber 312. [0036] A sleeve 320 of the diverter valve 300 is inserted into the bore 305 and is secured to the upper body 303 of the valve body 301. The sleeve 320 and the upper body 303 of the valve body 301 define a piston chamber 321 that receives the piston 309. The piston chamber 321 is sealed by a plurality of 0 ring seals (not depicted) that are located in a plurality of grooves 322 in the piston 309, and by an O-ring seal (not depicted) located in a groove 323 in the upper body 303. A steel O-ring (not depicted) whose function is to wipe an inner surface of the piston 309 clean when the piston 309 moves along the bore 305 is located in a groove 324 in the sleeve 320.

7 [0037] A third port 325 in the upper body 303 is connected to the piston chamber 321. [0038] An upper end 326 of the upper body 303 is machined or otherwise configured to suit a range of third party connectors for securing a blowout preventer valve (e.g. an annular blowout preventer valve), blind shear, grab ram, flexi joint, or lower marine riser package to the valve body 301. [0039] In use, the valve body 301 is secured relative to the subsea well so that the bore 305 is aligned with the wellbore and so that hydrocarbon fluid which flows out of the well flows into the bore 305. The piston 309 is in the closed position so that its lower end 311 is sealingly engaged with the valve seat 310 so that the fluid flowing from the wellbore into the bore 305 is unable to flow from the bore 305 and through the outlets 306. A drill string or other equipment which is not shown in the drawings may extend through the bore 305. [0040] In the event that the fluid flowing from the wellbore into the bore 305 needs to be diverted so that it flows through the outlets 306 rather than out through the bore 305, the diverter valve 300 is opened by moving the piston 309 upwardly along the bore 305. Piston 309 is moved upwardly along the bore 305 by pumping hydraulic fluid in to the lower section 315 of the piston chamber 312 through the first port 318, and by allowing hydraulic fluid in the upper section 316 of the piston chamber 312 and in the piston chamber 321 to be vented out through the ports 319 and 325, respectively. [0041] The rate at which the fluid flows through the outlets 306 is proportional to the amount by which the diverter valve 300 is opened. The further upward that the piston 309 is moved along the bore 305, the more open the diverter valve 300, and vice versa. [0042] After passing out of the valve body 301 through the outlets 306, the fluid flows through hoses or pipes that are connected to the outlets 306 and that lead to storage tanks which may be located on a ship or elsewhere so that the fluid is captured and does not pollute the environment. [0043] The open diverter valve 300 is closed by moving the piston 309 downwardly along the bore 305 until the lower end 311 of the piston 309 sealingly engages with the valve seat 310. This is accomplished by pumping 8 hydraulic fluid into the upper section 316 of the piston chamber 312 and into the piston chamber 321 through the ports 319 and 325, respectively, and by allowing the hydraulic fluid in the lower section 315 of the piston chamber 312 to be vented out of the lower section 315 through the port 318. [0044] The ports 319 and 325 may be connected to each other by a hose/ pipe 327 so that as the hydraulic fluid is vented out of one of the upper section 316 of the piston chamber 312 and the piston chamber 321, it can be transferred to the other of the upper section 316 and the piston chamber 321, with any excess hydraulic fluid being stored in a reservoir tank 328 connected to the ports 319, 325. [0045] Figure 3 depicts a second diverter valve 350 which is identical to the first diverter valve 300 except that it also includes an automatic fail-safe device/system 351 that is able to operate the diverter valve 350 in the event of the failure of other systems that are operable to control the valve 350. The automatic fail-safe device/system 351 includes a coil spring 352 that extends around the piston 309 and that is located on a lifting side of the piston 309 between the piston 309 and the valve body 301. The coil spring 352 is compressed when the diverter valve 350 is closed. If a problem arises and power or a signal is lost to the stack, a solenoid-operated valve (not depicted) of the diverter valve 350 will open so that hydraulic pressure on the opposite side of the piston 309 to the spring 352 will be released so as to allow the spring 352 to lift the piston 309 and open the diverter valve 350. Once the diverter valve 350 is opened the diverter valve 350 is able to divert the flow of fluid in the usual manner. [0046] Figure 4 depicts a third diverter valve 360 which is similar to the first diverter valve 300 and the second diverter valve 350. The valve body 301 of the valve 360 includes a plurality of inlets 361 that extend to the valve seat 310. The inlets 361 are part of a flushing or cleaning system that is operable to clean the valve seat 310 to ensure that a lower end of the piston 309 of the valve 360 is able to properly seal against the valve seat 310 when the valve 360 is closed. The flushing system functions by injecting a suitable cleaning fluid through the inlets 361 so that the fluid cleans the valve seat 310.

9 [0047] Although not shown in figure 4, the diverter valve 360 includes a plurality of choke and kill lines that are able to communicate with the bore 305 of the valve body 301. Each choke and kill line is able to be used to supply kill mud to the well to which the valve 360 is connected, measure the pressure in the well, periodically flush or clean the interior of the valve 360, and/or quench gas which may emanate from the well. A respective control valve (not depicted) connected in series with each choke and kill line is operable to open or close the line. [0048] The diverter valves 300, 350, and 360 are configurable as work through diverter valves so that drill strings, wirelines, or other equipment are able to be inserted through the diverter valves 300, 350, and 360 and the bores of the wells to which the valves 300, 350, and 360 are connected so that work can be carried out through the bores while the valves 300, 350, and 360 are connected to the wells. [0049] It will be appreciated by those skilled in the art that variations and modifications to the invention described herein will be apparent without departing from the spirit and scope thereof. The variations and modifications as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as herein set forth. [0050] Throughout the specification and claims, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. [0051] Throughout the specification and claims, unless the context requires otherwise, the term "substantially" or "about" will be understood to not be limited to the value for the range qualified by the terms. [0052] It will be clearly understood that, if a prior art publication is referred to herein, that reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

Claims

1. A diverter valve for a well, the diverter valve comprising a valve body including a passage through which a fluid flowing from the well is able to flow, and at least one outlet connected to the passage so that the fluid flowing through the passage is able to be diverted to flow from the passage and out of the valve body through each outlet, and a piston moveable along the passage so as to control the flow of the fluid through each outlet.

2. The diverter valve defined by claim 1, wherein the passage of the valve body comprises a bore.

3. The diverter valve defined by any one of the preceding claims, wherein the valve body includes a piston chamber that receives the piston such that the piston divides the piston chamber into a lower section and an upper section, a first port connected to the lower section, and a second port connected to the upper section.

4. The diverter valve defined by claim 3, wherein the valve body also comprises a lower body, and an upper body secured to the lower body.

5. The diverter valve defined by claim 4, wherein the piston chamber is defined by the lower body and the upper body.

6. The diverter valve defined by any one of claims 3 to 5, wherein the diverter valve also comprises a sleeve inserted into the passage and secured relative to the valve body, and a further piston chamber that receives the piston and that is defined by the sleeve and the valve body, and the valve body includes a third port connected to the further piston chamber.

7. The diverter valve defined by any one of the preceding claims, wherein the piston comprises a hollow piston.

8. The diverter valve defined by any one of the preceding claims, wherein the diverter valve also comprises an automatic fail-safe device/system that is able to operate the diverter valve in the event of the failure of other systems that are operable to control the diverter valve. 11

9. The diverter valve defined by any one of the preceding claims, wherein the valve body comprises a valve seat for the piston to rest against, and an inlet that extends to the the valve seat so that a fluid injected through the inlet is able to clean the valve seat.

10. The diverter valve defined by any one of the preceding claims, wherein the diverter valve also comprises a choke and kill line that is able to communicate with the passage of the valve body.

11. The diverter valve defined by claim 10, wherein the diverter valve also comprises a control valve that is connected to the choke and kill line.

12. A method of operating the diverter valve defined by any one of the preceding claims, the method comprising the steps of: allowing a fluid flowing from a well to flow through the passage of the valve body of the diverter valve; and moving the piston of the diverter valve along the passage so as to control the flow of the fluid from the passage and out of the valve body through each outlet of the valve body.

13. A diverter valve substantially as hereinbefore described with reference to the drawings.

14. A method of operating a diverter valve, the method being substantially as hereinbefore described with reference to the drawings.