A system for determining a fault in a subsea blowout preventer (BOP) stack includes a first sensor and a second sensor adapted to measure one or more properties of a subsea operation. The system further includes a first power supply adapted to provide operational power to the first sensor and a second power supply adapted to provide operational power to the second sensor. The system also includes a first power failure indicator and isolator (PFII) associated with the first sensor and the first power supply, the first PFII measuring a first pair of waveforms to identify a first fault and a second PFII associated with the second sensor and the second power supply, the second PFII measuring a second pair of waveforms to identify a second fault.

A valve for preventing hydraulic shock and water hammer in downstream equipment, the valve including a valve body with an internal oil dampening chamber, an orifice arranged within the oil dampening chamber, a flow dampener positioned between the valve inlet and the orifice, and a spring between the valve body and the orifice. The valve is pressure compensated based on the ambient fluid pressure.

A valve for preventing hydraulic shock and water hammer in downstream equipment, the valve including a valve body with an internal oil dampening chamber, an orifice arranged within the oil dampening chamber, a flow dampener positioned between the valve inlet and the orifice, and a spring between the valve body and the orifice. The valve is pressure compensated based on the ambient fluid pressure.

A rotating head assembly includes a body, an implement, a clamp assembly, a drive member, a hydraulic motor, and a bypass circuit. The drive member is threadingly connected to a first clamp member and a second clamp member. The hydraulic motor is connected to the drive member to cause the drive member to rotate in a selected direction. An inlet of the bypass circuit is in fluid communication with an inlet of the hydraulic motor to receive a portion of the pressurized hydraulic fluid passing to the hydraulic motor. An outlet of the bypass circuit is in fluid communication with the outlet of the hydraulic motor. At least one bypass valve is interposed between the inlet of the bypass circuit and the outlet of the bypass circuit. The bypass valve has an actuator positioned adjacent one of the first clamp member and the second clamp.

A rotating head assembly includes a body, an implement, a clamp assembly, a drive member, a hydraulic motor, and a bypass circuit. The drive member is threadingly connected to a first clamp member and a second clamp member. The hydraulic motor is connected to the drive member to cause the drive member to rotate in a selected direction. An inlet of the bypass circuit is in fluid communication with an inlet of the hydraulic motor to receive a portion of the pressurized hydraulic fluid passing to the hydraulic motor. An outlet of the bypass circuit is in fluid communication with the outlet of the hydraulic motor. At least one bypass valve is interposed between the inlet of the bypass circuit and the outlet of the bypass circuit. The bypass valve has an actuator positioned adjacent one of the first clamp member and the second clamp.

A control system for controlling disconnection of riser system that extends between a vessel and a subsea location that comprises a wellbore, the riser system configured to receive a string in use, the control system being configured to disconnect the riser system according to a sequence of operations, the sequence of operations comprising disconnecting the riser system prior to or simultaneous with cutting the string and sealing the well bore.

A control system for controlling disconnection of riser system that extends between a vessel and a subsea location that comprises a wellbore, the riser system configured to receive a string in use, the control system being configured to disconnect the riser system according to a sequence of operations, the sequence of operations comprising disconnecting the riser system prior to or simultaneous with cutting the string and sealing the well bore.

An underwater robotic system includes a frame adapted to be deployed in a body of water and having guide rails and at least one movable rail movably coupled to the guide rails. An actuator module is movably coupled to the at least one movable rail. A control panel disposed proximate the frame and has a plurality of controls thereon. The plurality of controls is operable by an actuator on the actuator module. A position of each of the plurality of controls is known such that motion of the actuator module and the at least one movable rail is remotely controllable to actuate any chosen one of the plurality of controls.

An underwater robotic system includes a frame adapted to be deployed in a body of water and having guide rails and at least one movable rail movably coupled to the guide rails. An actuator module is movably coupled to the at least one movable rail. A control panel disposed proximate the frame and has a plurality of controls thereon. The plurality of controls is operable by an actuator on the actuator module. A position of each of the plurality of controls is known such that motion of the actuator module and the at least one movable rail is remotely controllable to actuate any chosen one of the plurality of controls.

An annular blowout preventer (BOP). The annular BOP includes an annular housing having a base. The base includes a plurality of fasteners extending from an interior of the housing to an exterior of the housing via fastener holes formed through the connector base. The annular BOP further includes a seal plate positioned at least partially adjacent interior ends of the plurality of fastener. The annular BOP further includes an annular elastomeric element positioned within the interior of the housing and an annular piston positioned within the interior of the housing. The piston, when driven towards the elastomeric element, deforms the elastomeric element and forces the elastomeric element to constrict radially inward.