Abstract: A pressure regulator for a BOP stack includes a housing having an input port, an output port, and a pilot port and a regulator piston axially movable through the housing between an open position and a closed position. The regulator piston has an internal passage formed through its first axial end. When the regulator piston is in the open position, the internal passage is in fluid communication with the input and output ports. When the regulator piston is in the closed position, the internal passage is in fluid communication with the output port and fluidly isolated from the input port. A space with regulator fluid is also provided within the housing adjacent a second axial end of the regulator piston, opposite the first axial end, wherein the space is fluidly isolated from the input port and the output port in both the open position and the closed position.

Abstract: A method of reducing hydraulic shock in a BOP system including a pressure regulator having an input port and an output port, and a regulator piston that moves between an open and a closed position based on a change in hydraulic pressure applied to the regulator piston via a pilot port. The method includes initiating a function, and monitoring the state of the function as it is carried out to predict when the function nears the end of its cycle. The method also includes, when the function reaches a predetermined state, adjusting the hydraulic pressure on the regulator piston via the pilot port to gradually move the regulator piston between the open to the closed position to reduce fluid flow through the fluid path in a controlled manner to reduce hydraulic shock.

Abstract: A plurality of PODs for a lower marine riser package (LMRP) is disclosed. At least a first subsea electronics module (SEM) and a second SEM are provided in a first POD of the plurality of PODs. At least a third SEM and a fourth SEM are provided in a second pod. The third SEM is redundant with the first SEM and the fourth SEM is redundant with the second SEM. At least one selector circuit is provided to transmit an SEM select signal that electrically activates or electrically deactivates the first SEM separately from the third SEM. As a result, each of the SEMs in the plurality of PODs may be separately activated or deactivated without a need to turn off fluid provided to hydraulic valves in the first and the second PODs that are controlled by corresponding SEMs.

Abstract: A method of reducing hydraulic shock in a BOP system including a pressure regulator having an input port and an output port, and a regulator piston that moves between an open and a closed position based on a change in hydraulic pressure applied to the regulator piston via a pilot port. The method includes initiating a function, and monitoring the state of the function as it is carried out to predict when the function nears the end of its cycle. The method also includes, when the function reaches a predetermined state, adjusting the hydraulic pressure on the regulator piston via the pilot port to gradually move the regulator piston between the open to the closed position to reduce fluid flow through the fluid path in a controlled manner to reduce hydraulic shock.