Regulator having check valve manifold for use in subsea control circuit

A system used in a subsea environment with a hydraulic source, the system comprising:

• a gate valve having a movable gate;
• an actuator connected to the gate valve and being configured to move the movable gate in response to hydraulic pressure;
• a directional control valve having an input, an output, and a vent, the input in communication with the hydraulic source, the vent in communication with the subsea environment, the directional control valve being operable in first and second states, the directional control valve in the first state communicating the hydraulic pressure from the input to the output, the directional control valve in the second state communicating the output with the vent;
• a regulator connected at a supply-side with the output of the directional control valve and connected at an outlet-side with the actuator, the regulator being responsive in first and second regulator conditions to hydraulic pressure between the supply-side and the outlet-side, the regulator in the first regulator condition being configured to communicate the hydraulic pressure from the supply-side at a pressure drop to the outlet-side toward the actuator, the regulator in the second regulator condition being configured to prevent the hydraulic pressure at the outlet-side from communicating to the supply-side;
• and
• a bypass being responsive in first and second bypass conditions to the hydraulic pressure between the supply-side and the outlet-side, the bypass in the first bypass condition being configured to prevent the hydraulic pressure at the supply-side from bypassing the regulator to communicate with the actuator, the bypass in the second bypass condition being configured to permit at least a portion of the hydraulic pressure at the outlet-side to bypass the regulator and communicate with the supply-side toward the directional control valve.

A method used in a subsea environment, the method comprising:

• activating a gate valve actuator in response to a first differential in a hydraulic pressure at a supply-side of a regulator being greater than at an outlet-side of the regulator by:
• reducing the hydraulic pressure communicated from the supply-side connected with a hydraulic source to the outlet-side connected with the gate valve actuator by permitting the hydraulic pressure to pass through the regulator;
• and
• preventing the hydraulic pressure at the outlet-side from bypassing the regulator to the supply-side;
• and
• deactivating the gate valve actuator in response to a second differential in the hydraulic pressure at the outlet-side being greater than at the supply-side by:
• preventing the hydraulic pressure at the outlet-side from communicating through the regulator to the supply-side;
• and
• permitting at least a portion of the hydraulic pressure at the outlet-side to bypass the regulator to the supply-side.