Systems for sub-ambient pressure assisted actuation of subsea hydraulically actuated devices and related methods

Abstract

This disclosure includes systems and methods for actuation of subsea hydraulically actuated devices. Some systems use or include one or more subsea reservoirs, each having a body defining an interior volume configured to contain a sub-ambient internal pressure, the body defining an outlet in fluid communication with the interior volume, and a hydraulic power delivery system including one or more subsea valves configured to selectively allow fluid communication between the outlet of at least one of the reservoir(s) and a first port of the hydraulically actuated device. In some systems, the hydraulic power delivery system includes a rigid sliding member configured to unseal a selectively sealed outlet of at least one of the reservoir(s). In some systems, the subsea valve(s) are configured to alternatively allow fluid communication between the outlet of the at least one of the reservoir(s) and the first or a second port of the hydraulically actuated device.

1 . (canceled) 
     
     
         2 . A system for actuating a subsea hydraulically actuated device, the system comprising:
 one or more subsea reservoirs, each comprising:
 a body defining an interior volume configured to contain an internal pressure that is lower than a pressure of a subsea environment outside of the body, the body defining an outlet in fluid communication with the interior volume; 
 where the outlet is selectively sealed; and 
   a hydraulic power delivery system comprising:
 a rigid sliding member configured to unseal the outlet of at least one of the one or more reservoirs; and 
 one or more subsea valves; 
 where the one or more subsea valves are configured to selectively allow fluid communication between the outlet of the at least one of the one or more reservoirs and a first port of the hydraulically actuated device. 
   
     
     
         3 . The system of  claim 2 , where:
 the outlet of the at least one of the one or more reservoirs comprises a diaphragm; and   the rigid sliding member is configured to puncture the diaphragm to unseal the outlet of the at least one of the one or more reservoirs.   
     
     
         4 . The system of  claim 3 , where the rigid sliding member comprises:
 a ram slidably disposed within a bore and movable between a first position and a second position, the ram configured to puncture the diaphragm as the ram is moved between the first position and the second position;   where fluid communication between the bore and the outlet is permitted when the ram is in the second position.   
     
     
         5 . (canceled) 
     
     
         6 . A system for actuating a subsea hydraulically actuated device, the system comprising:
 one or more subsea reservoirs, each comprising a body defining an interior volume configured to contain an internal pressure that is lower than a pressure of a subsea environment outside of the body, the body defining an outlet in fluid communication with the interior volume; and   a hydraulic power delivery system comprising:
 one or more subsea valves; 
 where the one or more subsea valves are configured to alternatively allow fluid communication between the outlet of at least one of the one or more reservoirs and a first port of the hydraulically actuated device or a second port of the hydraulically actuated device. 
   
     
     
         7 . The system of  claim 6 , where:
 the outlet of the at least one of the one or more reservoirs is selectively sealed; and   the hydraulic power delivery system comprises a rigid sliding member configured to unseal the outlet of the at least one of the one or more reservoirs.   
     
     
         8 . The system of  claim 7 , where:
 the outlet of the at least one of the one or more reservoirs comprises a diaphragm; and   the rigid sliding member is configured to puncture the diaphragm to unseal the outlet of the at least one of the one or more reservoirs.   
     
     
         9 . The system of  claim 8 , where the rigid sliding member comprises:
 a ram slidably disposed within a bore and movable between a first position and a second position, the ram configured to puncture the diaphragm as the ram is moved between the first position and the second position;   where fluid communication between the bore and the outlet is permitted when the ram is in the second position.   
     
     
         10 . (canceled) 
     
     
         11 . The system of  claim 6 , where the one or more subsea valves are configured to selectively allow fluid communication between a pressure source and the second port of the hydraulically actuated device. 
     
     
         12 . The system of  claim 11 , where the one or more subsea valves comprises:
 a third two-way valve configured to selectively allow fluid communication between the pressure source and the second port of the hydraulically actuated device; and   a fourth two-way valve configured to selectively allow fluid communication between the outlet of the at least one of the one or more reservoirs and the second port of the hydraulically actuated device.   
     
     
         13 . The system of  claim 11 , where the one or more subsea valves comprises a second three-way valve configured to:
 selectively allow fluid communication between the pressure source and the second port of the hydraulically actuated device; and   selectively allow fluid communication between the outlet of the at least one of the one or more reservoirs and the second port of the hydraulically actuated device.   
     
     
         14 . The system of any of  claim 6 , where the one or more subsea valves are configured to selectively allow fluid communication between a pressure source and the first port of the hydraulically actuated device. 
     
     
         15 . The system of  claim 14 , where the one or more subsea valves comprises:
 a first two-way valve configured to selectively allow fluid communication between the pressure source and the first port of the hydraulically actuated device; and   a second two-way valve configured to selectively allow fluid communication between the outlet of the at least one of the one or more reservoirs and the first port of the hydraulically actuated device.   
     
     
         16 . The system of  claim 14 , where the one or more subsea valves comprises a first three-way valve configured to:
 selectively allow fluid communication between the pressure source and the first port of the hydraulically actuated device; and   selectively allow fluid communication between the outlet of the at least one of the one or more reservoirs and the first port of the hydraulically actuated device.   
     
     
         17 . The system of  claim 14 , where the pressure source comprises sea water from a subsea environment. 
     
     
         18 . The system of  claim 14  where the pressure source comprises a subsea pump. 
     
     
         19 . (canceled) 
     
     
         20 . The system of  claim 6 , where at least one of the one or more reservoirs comprises an accumulator. 
     
     
         21 - 28 . (canceled) 
     
     
         29 . The system of  claim 2 , comprising a battery configured to supply electrical power to the hydraulic power delivery system. 
     
     
         30 . (canceled) 
     
     
         31 . A method for actuating a subsea hydraulically actuated device, the method comprising:
 unsealing a sealed outlet of a subsea reservoir, the reservoir defining an interior volume in fluid communication with the outlet, the interior volume containing an internal pressure that is lower than a pressure of a subsea environment outside of the reservoir; and   placing the outlet of the reservoir into fluid communication with a first port of the hydraulically actuated device.   
     
     
         32 . The method of  claim 31 , where unsealing the sealed outlet of the subsea reservoir comprises puncturing a seal of the reservoir. 
     
     
         33 . The method of  claim 31 , comprising:
 placing a second port of the hydraulically actuated device into fluid communication with a pressure source.   
     
     
         34 - 37 . (canceled)