Abstract: Drilling mud is lifted subsea to a drilling vessel with a mud pump having an internal bladder. Applying pressurized water to one side of the bladder urges it against a quantity of the mud to impart a lifting force onto the mud. Mud flow to and from the pump is controlled by valves driven by actuators. The actuators include a piston in a cylinder, a stem that connects the piston to a valve member, and ports for supplying fluid to opposing ends of the piston for selectively reciprocating the piston. Cavities are strategically location in the cylinder for absorbing vibrational forces generated when the piston reaches an end of its stroke.

Abstract: A method and system for lifting drilling mud from subsea to a drilling vessel includes a pump having a body with a chamber, and a bladder in the chamber. The bladder spans the chamber to define water and mud sides in the chamber. A mud inlet valve allows mud into the mud side of the chamber; which moves the bladder into the water side and urges water from the water side of the chamber through a water exit valve. Pressurized water enters the chamber through a water inlet valve, which in turn pushes the bladder and mud from the chamber through a mud exit valve. The bladder separates the mud and water as it reciprocates in the chamber. A pressure control circuit equalizes pressure across the water valves, and a control valve provides a back pressure in a discharge of the pressure control circuit.

Abstract: A method and system for lifting drilling mud from subsea to a drilling vessel includes a pump having a body with a chamber, and a bladder in the chamber. The bladder spans the chamber to define water and mud sides in the chamber. A mud inlet valve allows mud into the mud side of the chamber; which moves the bladder into the water side and urges water from the water side of the chamber through a water exit valve. Pressurized water enters the chamber through a water inlet valve, which in turn pushes the bladder and mud from the chamber through a mud exit valve. The bladder separates the mud and water as it reciprocates in the chamber. A pressure control circuit equalizes pressure across the water valves, and a control valve provides a back pressure in a discharge of the pressure control circuit.

Abstract: Drilling mud is lifted subsea to a drilling vessel with a mud pump having an internal bladder. Applying pressurized water to one side of the bladder urges it against a quantity of the mud to impart a lifting force onto the mud. Mud flow to and from the pump is controlled by valves driven by actuators. The actuators include a piston in a cylinder, a stem that connects the piston to a valve member, and ports for supplying fluid to opposing ends of the piston for selectively reciprocating the piston. Cavities are strategically location in the cylinder for absorbing vibrational forces generated when the piston reaches an end of its stroke.

Abstract: A method and system for lifting drilling mud from subsea to a drilling vessel, which uses a pump having a body with a chamber, and a bladder in the chamber. The bladder attaches to the body and defines water and mud sides in the chamber. A mud inlet valve allows mud into the mud side of the chamber; which moves the bladder into the water side and urges water in the water side from the chamber and through a water exit valve. Pressurized water enters the chamber through a water inlet valve, which in turn pushes the bladder and mud from the chamber through a mud exit valve. The bladder separates the mud and water as it reciprocates in the chamber. The travel of the bladder in the chamber is controlled to prevent damage from contact with the chamber.

Abstract: A method for lifting drilling mud from subsea to a drilling vessel which a pump having a body with a chamber, and a bladder in the chamber. The bladder attaches to the body and defines water and mud sides in the chamber. A mud inlet valve allows mud into the mud side of the chamber; which moves the bladder into the water side and urges water in the water side from the chamber and through a water exit valve. Pressurized water enters the chamber through a water inlet valve, which in turn pushes the bladder and mud from the chamber through a mud exit valve. The bladder separates the mud and water as it reciprocates in the chamber. Water and/or mud inlet valves are opened before associated exit valves to reduce pressure fluctuations in the fluid lines.