Abstract: A fluid-flow control device includes a valve aperture and a mounting member arranged downstream of the aperture. A valve member, movably mounted on the mounting member, controls the flow of fluid through the aperture. A control volume, defined between the mounting member and the valve member receives a control fluid from a control fluid feed. A variable flow restrictor is rotatably arranged within a restriction volume of the control fluid feed such that a flow path connecting the inlet, and the outlet, of the restriction volume is defined between the restrictor and the wall of the restriction volume. The restrictor is axi-symmetric about its axis of rotation.

Abstract: A device for controlling the flow of a fluid through a conduit from an upstream side of the device to a downstream side of the device. The device includes an upstream valve casing defining an inlet, a downstream valve casing defining an outlet aperture, and a valve core secured between the upstream valve casing and the downstream valve casing. The upstream valve casing, the downstream valve casing and the valve core are formed as discrete parts. The valve core includes a housing defining a control volume. The valve member is mounted on the housing and positioned on the upstream side of the outlet aperture, the valve member being arranged to move reciprocally to selectively open and close the outlet aperture, thereby controlling flow of the fluid through the outlet aperture.

Abstract: A device for controlling the flow of a fluid through a conduit from an upstream side of the device to a downstream side of the device. The device includes a housing defining a valve aperture and a mounting member arranged on the downstream side of the valve aperture. A valve member is movably mounted on the mounting member and is arranged to selectively open and close the valve aperture to control the flow of fluid. A soft seal is arranged on the housing for substantially sealing the valve aperture when the valve member contacts the housing. The soft seal is located downstream of a convex curved surface of the housing which is shaped to separate the flow of fluid through the valve aperture away from the surface of the housing such that the fluid does not impinge directly on the soft seal.

Abstract: A device for controlling the flow of a fluid through a conduit from an upstream side of the device to a downstream side of the device. The device includes a valve housing having defined therein a valve aperture, a valve member movably mounted relative to the valve aperture. The valve member is arranged to be displaced reciprocally in a direction to selectively open and close the valve aperture. The device also includes a magnet mounted on or relative to the valve member, with the magnet being displaced by displacement of the valve member. A plurality of magnetic field sensors are mounted on the valve housing.

Abstract: A device for controlling the flow of fluid through a conduit from an upstream side of the device to a downstream side of the device. The device includes a valve seat mounted on a casing that defines a valve aperture, a mounting member arranged on the downstream side of the valve aperture; a valve member mounted on the mounting member. The valve member is arranged to selectively open and close the valve aperture thereby controlling the flow of the fluid through the valve aperture. A seal retaining member is arranged adjacent the valve seat and, with the valve seat, defines a seal retaining groove. A compliant seal within the seal retaining groove seals the valve aperture when the valve member is moved to close the valve aperture.

Abstract: An actuator for a pilot valve, including a housing, a piston movably mounted in the housing and an actuator chamber defined between the piston and the housing. The actuator includes a control fluid feed for introducing a fluid into the actuator chamber to control fluid pressure, with the fluid pressure acting on the piston. The actuator also includes an actuation member for acting on the pilot valve and a loading spring between the piston and the actuation member. The loading spring is arranged to bias the piston against the fluid pressure in the actuator chamber. The control fluid feed controls the fluid pressure so the fluid pressure acts on the piston against the bias of the loading spring to control the biasing force.

Abstract: A device for controlling the flow of a fluid through a conduit from an upstream side of the device to a downstream side of the device is provided. The device includes an upstream valve casing defining an inlet, a downstream valve casing defining an outlet aperture, and a valve core secured between the upstream valve casing and the downstream valve casing. The upstream valve casing, the downstream valve casing and the valve core are formed as discrete parts. The valve core includes a housing defining a control volume. The valve member is mounted on the housing and positioned on the upstream side of the outlet aperture, the valve member being arranged to move reciprocally to selectively open and close the outlet aperture, thereby controlling flow of the fluid through the outlet aperture.

Abstract: A device is provided for controlling the flow of a fluid through a conduit from an upstream side to a downstream side of the device. The device includes a valve aperture, a cylindrical mounting member on the downstream side of the valve aperture, a valve member on the outside of the cylindrical mounting member that moves reciprocally to open and close the valve aperture, a control volume defined between the cylindrical mounting member and the valve member, an arrangement for introducing a control pressure into the control volume, and a seal between the outer surface of the cylindrical mounting member and the inner surface of the valve member that substantially seals the control volume. The valve member is acted on by the pressure of the upstream side (P1) and the control pressure (P4) so as to be moved by the difference between these pressures.