AU2015213314A1

AU2015213314A1 - Blowout preventor actuation tool

Info

Publication number: AU2015213314A1
Application number: AU2015213314A
Authority: AU
Inventors: Michael Alexander Bisset
Original assignee: Specialist ROV Tooling Services Ltd
Current assignee: Forum Energy Technologies UK Ltd
Priority date: 2011-11-10
Filing date: 2015-08-12
Publication date: 2015-09-03
Anticipated expiration: 2031-11-10
Also published as: AU2011250707B2; AU2015213314B2; AU2011250707A1

Abstract

H:\dxl\Intrwovn\NRPortbl\DCC\DXL\8180377_ .docx-10/08/2015 A system for actuating a blow out preventer ("BOP"), comprising a remotely operated underwater vehicle ("ROV"); and a tool fluidly connected to the ROV, wherein the ROV is configured to power one or more pumps contained within the tool to increase pressure and flow rate of fluid from a fluid source to the BOP until the BOP is fully actuated, and wherein the tool is movable between a first position in which the tool is connected to the BOP and a second position in which the tool is disconnected from the BOP. Q / C cu U- e -D u- c r c(3 ----------

Description

H:\dxl\lntroven\NRPortbl\DCC\DXL\8180377_ .docx-10/08/2015 1 BLOWOUT PREVENTOR ACTUATION TOOL [0001] This application is a divisional of Australian Patent Application No. 2011250707, the entire content of which is incorporated herein by reference. BACKGROUND OF THE INVENTION Field of the Invention [0002] Embodiments of the present invention generally relate to a tool used in a subsea environment to help prevent the release of hydrocarbons into a body of water. More particularly, the invention relates to a tool that is connected to a remotely operated underwater vehicle ("ROV"), which provides a high flow rate of fluid at a high pressure to a blowout preventer ("BOP") to manually actuate the BOP. Description of the Related Art [0003] A blowout preventer ("BOP") is a large piece of specialized oilfield equipment that is used to seal, control and monitor oil and gas wells. In a subsea environment, the BOP is attached to the top of the wellhead at the bottom of the ocean. The BOP then connects to an offshore rig through a drilling riser. Drill strings are lowered inside the drilling riser and through the BOP and rotated by equipment on the offshore rig to turn a drill bit and drill an oil and/or gas well. [0004] As an oil and gas well is being drilled, the well can receive what is called a formation kick, which is a burst of high pressure that comes from the reservoir. These kicks can cause a variety of catastrophic events, such as drill pipe and casing being blown out of the wellbore, and, in severe cases, hydrocarbons being released into the ocean. The BOP is designed to prevent these catastrophic blow outs from occurring, or at the very least, to minimize their effects when they do occur. [0005] Typically, when a kick occurs, the BOP is closed so that fluids do not flow out of the wellbore. More specifically, rams or shears in the BOP are closed which effectively close and seal the drilling riser, drill strings and associated piping that runs through the BOP. The BOP rams or shears are closed remotely, either by workers actuating the BOP from an offshore rig or by an automated actuation system.

H:\dxl\lntroven\NRPortbl\DCC\DXL\8180377_ .docx-10/08/2015 2 [0006] When the BOP cannot be actuated remotely, there is a need for an apparatus, system and method of manually actuating a BOP at a rapid speed in the event the BOP cannot be remotely actuated. SUMMARY OF THE INVENTION [0007] The present invention relates to a tool, method and system for actuating a BOP in a subsea environment. In one embodiment, a tool for actuating a BOP in a subsea environment includes a high pressure pump, one or more high flow pumps, hydraulic connections for connection to an ROV and a connector for use with a BOP. The tool uses hydraulic power provided by the ROV to pump fluid through the high flow pump(s) and out to the BOP until the fluid reaches a certain pressure, and then the hydraulic power is shifted to the high pressure pump to pump fluid to the BOP until the BOP is fully actuated. [0008] The invention also provides a system for actuating a blow out preventer ("BOP"), comprising: a remotely operated underwater vehicle ("ROV"); and a tool fluidly connected to the ROV, wherein the ROV is configured to power one or more pumps contained within the tool to increase pressure and flow rate of fluid from a fluid source to the BOP until the BOP is fully actuated, and wherein the tool is movable between a first position in which the tool is connected to the BOP and a second position in which the tool is disconnected from the BOP. [0009] The invention also provides a method for actuating a blow out preventer, comprising: connecting an actuation tool to the blow out preventer; supplying power from a remotely operated underwater vehicle to the actuation tool; increasing a pressure and a flow rate of an actuation fluid pumped by the actuation tool; supplying the actuation fluid from the actuation tool to the blow out preventer to actuate the blow out preventer; and H:\dxl\lntroven\NRPortbl\DCC\DXL\8180377_ .docx-10/08/2015 3 disconnecting the actuation tool from the blow out preventer once the blow out preventer is fully actuated. BRIEF DESCRIPTION OF THE DRAWINGS [0010] So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. [0011] Figure 1 is a perspective view of an embodiment of a tool used to close a blow out preventer ("BOP"), which shows various connections used to connect the tool to a remotely operated underwater vehicle ("ROV") and includes one high pressure pump and two high flow pumps. [0012] Figures 2 and 3 are schematics of the tool shown in Figure 1, wherein Figure 2 illustrates the tool when seawater is used to operate pumps housed in the tool, and wherein Figure 3 illustrates the tool when a fluid housed in one or more reservoirs is used to operate the pumps in the tool. [0013] Figure 4 illustrates two connections of the tool, which are used when fluid, other than seawater, is pumped through the tool. [0014] Figures 5A and 5B illustrate a connection of the tool and a filter needed when seawater is pumped through the tool. [0015] Figure 6 is a perspective view of another embodiment of the tool, which includes one high pressure pump and one high flow pump. [0016] Figure 7 is a perspective view of the embodiment of the tool shown in Figure 6, which shows various connections used to connect the tool to the ROV.

H:\dxl\lntroven\NRPortbl\DCC\DXL\8180377_ .docx-10/08/2015 4 [0017] Figures 8 and 9 illustrate connections of the tool shown in Figures 6 and 7 to the fluid source: gloycol/oil and seawater, respectively. [0018] Figure 10 is a schematic of the embodiment of the tool shown in Figures 6 9. [0019] Figure 11 is flow diagram showing a system for closing a BOP. DETAILED DESCRIPTION [0020] In one embodiment, a tool enables a blow out preventer ("BOP") to be rapidly closed such as when the BOP cannot be closed by a remote means. The tool is mounted to a remotely operated underwater vehicle ("ROV"), and the ROV provides hydraulic power to the tool. The tool is further connected to the BOP, such as by use of a hot stab connection, and is configured to push fluid to the BOP in order to actuate the BOP. The tool includes a high pressure pump and one or more high flow pumps. The tool first runs fluid through one or more high flow pumps until the fluid reaches a predetermined (elevated) pressure, and then switches the fluid flow to a high pressure pump. Because the tool is able to rapidly increase the pressure and flow rate of the fluid flowing to the BOP, the BOP may be closed at a rapid speed. In one embodiment, the tool of the present invention can fully actuate most BOPs in under 60 seconds, thereby sealing the wellbore and protecting the wellhead equipment and environment from further damage. [0021] Figure 1 is a perspective view of an embodiment of the tool 100 used to close the BOP 300, and shows various connections used to connect the tool 100 to the ROV 200, as well as several component parts of the tool 100. This particular embodiment of the tool 100 includes one high pressure pump 140 and two high flow pumps 150A, B. The tool 100 receives hydraulic power from the ROV 200 via a line connected to a pressure connector 102, and the tool 100 relieves any excess pressure through an ROV line running to a return connector 104. The ROV 200 is also connected to two pilot operated check valves 11 0A, B, which allow the hydraulic pressure to reach either the high pressure pump 140 or the two high flow pumps 150 A, B. The fluid 170 being pumped by the tool 100 is directed to the BOP 300. In the H:\dxl\lntroven\NRPortbl\DCC\DXL\8180377_ .docx-10/08/2015 5 preferred embodiment, a hot stab is connected to a BOP connector 190 of the tool 100, which in turn is connected to the BOP 300. [0022] Figures 2 and 3 are detailed schematics of the embodiment of the tool 100 shown in Figure 1, wherein Figure 2 illustrates the tool 100 when seawater is the fluid 170 used to operate the tool, and wherein Figure 3 illustrates the tool when a fluid 170 housed in one or more reservoirs, such as glycol or oil, is used to operate the pumps 140, 150A, B in the tool 100. The operation of the tool in Figures 2 and 3 are identical except where noted. The tool 100 is connected to the ROV 200 via an ROV pressure line 220 and ROV return line 230. The ROV pressure line 220 and ROV return line 230 are connected to the pressure connector 102 and return connector 104, respectively (shown in Figure 1). The tool 100 is also connected to the ROV 200 using an ROV general function valve pack ("ROV GFVP") 250, which provides hydraulic pressure to at least two pilot operated check valves 11 0A, B. [0023] When the tool 100 is initially used, the ROV GFVP 250 routes hydraulic pressure to the pilot operated check valve 11 OB located directly upstream of a flow priority valve 120 and to high flow pumps 150A, B. This pressure opens the pilot operated check valve 11 OB and allows pressure to flow to the flow priority valve 120. Once pressure upstream of the flow priority valve 120 reaches a minimum pressure set by the flow priority valve 120, the valve 120 opens and allows the hydraulic pressure to operate the high flow pumps 150A, B. An exemplary high flow pump 150 for use in the tool 100 of the present invention is a Dynaset HPW 90/150-85 pump. [0024] The high flow pumps 150A, B take fluid 170A, B and pumps the fluid 170A, B out to the BOP 300, preferably through a hot stab connection 195. A check valve 164 ensures fluid does not flow back to the high flow pumps 150A, B. A gauge 180 on the downstream side of the high flow pumps 150A, B, and upstream of the BOP output 190, allows pressure to be monitored. As the fluid 170A, B circulates through the high flow pumps 150A, B, and out to the BOP 300, flow rate and pressure of the fluid 170A, B increases.

H:\dxl\lntroven\NRPortbl\DCC\DXL\8180377_ .docx-10/08/2015 6 [0025] The fluid 170 can be seawater 170A, glycol 170B, or any other oil or fluid appropriate for subsea operations. If the fluid 170 is glycol 170B or any other oil, such fluid 170B is stored in reservoirs near the tool 100. The fluid is then connected via appropriate hoses to fluid connectors 175 in the tool 100. Examples of these fluid connectors 175A, B, which are attached to the pumps 140, 150 of the tool 100, are shown in Figure 4. If the tool 100 uses seawater 1 70A as the fluid 170, the same fluid connectors 175 (as shown in Figure 4 and 5) are used to receive the seawater 170A, but a filter hose assembly 177, shown in Figure 5, may be attached to the fluid connector 175. [0026] Turning back to Figures 2 and 3, the hydraulic power of the ROV 200 may be shifted away from the high flow pumps 150A, B to the high pressure pump 140 by providing pressure from the ROV GFVP 250 to the pilot operated check valve 11 CA that is directly upstream of the high pressure pump 140. By moving the pressure away from the pilot operated check valve 11 OB, the check valve 11 OB closes, and pressure may no longer circulate and operate the high flow pumps 150A, B. After this shift, hydraulic power is only provided to the high pressure pump 140. [0027] After pilot operated check valve 11 CA is opened, pressure flows through a flow control valve 130 to the high pressure pumps 140. An exemplary high pressure pump 140 for use in the tool 100 of the present invention is a Dynaset HPW 520/30 85 pump. The high pressure pump 140 takes fluid 170A, B and pumps the fluid 170A, B out to the BOP 300, once again, preferably througha hot stab connection. A relief valve 162 is located downstream of the high pressure pump 140 to relieve pressure from the system should it exceed a specified pressure (preferably, the maximum pressure on the system is 5000 psi), and once again, the check valve 164 prevents fluid from flowing back to the high flow pumps 150A, B. When the tool 100 includes one Dynaset HPW 520/30-85 high pressure pump and two Dynaset HPW 90/50-85 high flow pumps, the tool 100 can increase the fluid pressure from approximately 3000 psi to 7000 psi, and can increase the flow rate from approximately 100-150 L/min to 200-300 L/min.

H:\dxl\lntroven\NRPortbl\DCC\DXL\8180377_ .docx-10/08/2015 7 [0028] Figure 6 is a perspective view of yet another embodiment of the tool 100, which comprises one high pressure pump 140 and one high flow pump 150. This embodiment operates in substantially the same manner, and is configured substantially the same as the embodiment shown in Figures 1-5. [0029] Figure 7 is another perspective view of the alternate embodiment of the tool 100 shown in Figure 6, which shows various connections used to connect the tool 100 to the ROV 200. The same hydraulic connections shown in Figure 1 are shown in Figure 7, with the addition of a depressurization valve 198. The depressurization valve 198 is used to bleed pressure off of the tool 100 once the tool 100 has completely actuated the BOP 300. [0030] Figures 8 and 9 illustrate the fluid connections 175A, B of the tool 100 that receive the hoses that carry fluid 170. Similar to Figure 4, Figure 8 shows the basic fluid connector 175B that is used for glycol, oil, and other fluids 170B kept in a reservoir. Similar to Figures 5A and 5B, Figure 9 shows the fluid connector 175A connected to the filter hose assembly 177 when seawater 170A is used in the tool 100. [0031] Figure 10 is a schematic of the embodiment of the tool 100 shown in Figures 6-9. The embodiment of this tool is almost identical to the embodiment of the tool 100 shown in Figures 1-5, except, as discussed, this embodiment of the tool 100 contains only one high pressure pump 140 and one high flow pump 150. In addition, instead of one check valve being used downstream of the high flow pump 150, several check valves 164A, B are placed downstream of the high flow pump 140. These valves 164A, B ensure pressure is not removed from the system. In addition, a depressurization valve 166 is placed downstream of the pumps 140, 150, which allows the tool 100 to be bled of all pressure once the BOP 300 has been fully actuated. Otherwise, the tool 100 shown in Figures 1-5 operates substantially identical to the tool 100 shown in Figures 6-10. When the tool 100 is configured with one Dynaset HPW 520/30-85 high pressure pump and one Dynaset HPW 90/50-85 high flow pump, the tool 100 can increase the fluid pressure from approximately 3000 H:\dxl\lntroven\NRPortbl\DCC\DXL\8180377_ .docx-10/08/2015 8 psi to 7000 psi, and can increase the flow rate from approximately 35-85 L/min to 70 150 L/min. [0032] The tool 100 may be configured as a component that can be bolted onto the ROV 200 directly, along with reservoirs for holding fluid 170 if desired, or the tool 100 may be placed on a skid and used on or near the ROV 200, depending on the ROV configuration. [0033] The method of actuating a BOP 300 includes hydraulically connecting a tool 100, such as the tool 100 disclosed above, to an ROV 200 on its upstream side, and connecting the tool 100 to the BOP 300 on the downstream side. Initially, hydraulic power from the ROV 200 is used to operate one or more high flow pumps 150A, B contained within the tool 100, and once the pressure of the fluid 170 being pumped through the tool 100 to the BOP 300 reaches 1300 - 1500 psi, the hydraulic power is switched to operate the high pressure pump 140 within the tool 100. In the preferred method of the invention, if the pressure of the fluid 170 drops below 1300 psi during operation of the high pressure pump 140, the hydraulic power is switched back to operate one or more high flow pumps 150A, B within the tool 100. Once the BOP 300 is fully actuated by using this method, the tool 100 is then disconnected from the BOP 300, and the tool 100 is depressurized by activating a depressurization valve 198 and allowing the pressure to bleed off to atmosphere. [0034] Figure 11 is flow diagram showing a system for closing the BOP 300. In the system, the ROV 200 supplies hydraulic power to the tool 100, and the tool pumps fluid 170 from an external source out to the BOP 300. The tool 100 uses a high pressure pump 140 and one or more high flow pumps 150, which in turn increases the pressure and flow rate of the fluid 170 being pumped to the BOP 300. Because the fluid 170 is pumped to the BOP 300 at a high pressure and flow rate, the BOP is able to be fully actuated at a rapid speed. [0035] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing H:\dxl\Intrwovn\NRPortbl\DCC\DXL\8180377 L.docx-10/08/2015 9 from the basic scope thereof, and the scope thereof is determined by the claims that follow. [0036] The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates. [0037] Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

Claims

1. A system for actuating a blow out preventer ("BOP"), comprising: a remotely operated underwater vehicle ("ROV"); and a tool fluidly connected to the ROV, wherein the ROV is configured to power one or more pumps contained within the tool to increase pressure and flow rate of fluid from a fluid source to the BOP until the BOP is fully actuated, and wherein the tool is movable between a first position in which the tool is connected to the BOP and a second position in which the tool is disconnected from the BOP.

2. A method for actuating a blow out preventer, comprising: connecting an actuation tool to the blow out preventer; supplying power from a remotely operated underwater vehicle to the actuation tool; increasing a pressure and a flow rate of an actuation fluid pumped by the actuation tool; supplying the actuation fluid from the actuation tool to the blow out preventer to actuate the blow out preventer; and disconnecting the actuation tool from the blow out preventer once the blow out preventer is fully actuated.

3. The method of claim 2, wherein the power is used to operate a high flow pump in the tool until the pressure of the actuation fluid reaches a predetermined pressure.

4. The method of claim 3, wherein after the predetermined pressure is reached, power is shifted from operating the high flow pump to operating a high pressure pump in the actuation tool to increase the pressure of the actuation fluid within the BOP.

5. The method of claim 4, wherein if the pressure of the actuation fluid drops below the predetermined pressure when the high pressure pump is operating, then H:\dxl\Intrwovn\NRPortbl\DCC\DXL\8180377 L.docx-10/08/2015 11 power is shifted from operating the high pressure pump to operating the high flow pump.

6. The method of claim 3, wherein a plurality of high flow pumps are used.

7. The method of claim 2 wherein the remotely operated underwater vehicle hydraulically powers the actuation tool.

8. A method for actuating a blow out preventer substantially as hereinbefore described with reference to the accompanying drawings.

9. A system for actuating a blow out preventer substantially as hereinbefore described with reference to the accompanying drawings.