A pressure reducing valve includes a piston disposed in a cylinder chamber; a valve element that is coupled to the piston and opens and closes a valve seat; a valve spring that biases the valve element in a direction in which the valve element is moved away from the valve seat; and a biasing member that biases the valve seat toward a side opposite to the piston. The pressure reducing valve is configured to reduce a primary pressure of a fluid to a secondary pressure. The valve seat is disposed such that the valve seat reciprocates in the same direction as a direction in which the valve element reciprocates in the primary pressure chamber. As a difference between the primary pressure and the secondary pressure increases, the valve seat moves toward the secondary pressure chamber.

The disclosure concerns a pressure relief valve. The pressure relief valve includes a base member having a support element extending therefrom. A moveable housing is slideably attached to the support element, with the support element designed to allow the moveable housing to travel toward and away from the base member. A housing guide is located within the moveable housing, with the housing guide adjustably attached to the support element, and slideably attached to the moveable housing. During operation, the moveable housing extends from and retracts toward the base member, thereby opening and closing the pressure relief valve.

A pressure regulator includes a piston assembly having a primary piston, secondary piston, and valve seat positioned inside an internal chamber divided into a primary chamber and a secondary chamber, such that the primary piston and valve seat are positioned inside the primary chamber and the secondary piston is positioned inside the secondary chamber, where the piston assembly moves longitudinally along the axis of the internal chamber in response to the pressures exerted on the primary piston and valve seat by a working liquid flowing into the primary chamber, and where a supplemental fluid is selectively introduced into the secondary chamber to exert a force on the secondary piston to modify the longitudinal movement of the piston assembly and thereby regulate flow of the working fluid through the primary chamber.

Described is a system for remotely detecting and signalling the open and/or closed state of the shutter (O) of an element (3) for controlling the flow of gas along a gas distribution line (2), comprising an electric switch (17; 18) configured to generate an electrical signal representing at least one of the open and closed states.

A pressure reducing valve includes a piston disposed in a cylinder chamber; a valve element that is coupled to the piston and opens and closes a valve seat; a valve spring that biases the valve element in a direction in which the valve element is moved away from the valve seat; and a biasing member that biases the valve seat toward a side opposite to the piston. The pressure reducing valve is configured to reduce a primary pressure of a fluid to a secondary pressure. The valve seat is disposed such that the valve seat reciprocates in the same direction as a direction in which the valve element reciprocates in the primary pressure chamber. As a difference between the primary pressure and the secondary pressure increases, the valve seat moves toward the secondary pressure chamber.

A pressure relief valve is provided. The pressure relief valve includes a hollow body having an inlet and an outlet, with the hollow body including at least one aperture extending through a surface of the hollow body. An actuator assembly is attached to the hollow body and a sleeve is slideably positioned about the hollow body, with the sleeve moveably attached to the actuator assembly. During operation, the actuator assembly moves the sleeve from a first position that covers the aperture to a second position that un-covers at least a portion of the aperture.

A pressure regulator includes a piston assembly having a primary piston, secondary piston, and valve seat positioned inside an internal chamber divided into a primary chamber and a secondary chamber, such that the primary piston and valve seat are positioned inside the primary chamber and the secondary piston is positioned inside the secondary chamber, where the piston assembly moves longitudinally along the axis of the internal chamber in response to the pressures exerted on the primary piston and valve seat by a working liquid flowing into the primary chamber, and where a supplemental fluid is selectively introduced into the secondary chamber to exert a force on the secondary piston to modify the longitudinal movement of the piston assembly and thereby regulate flow of the working fluid through the primary chamber.

A pressure relief valve is provided. The pressure relief valve includes a hollow body having an inlet and an outlet, with the hollow body including at least one aperture extending through a surface of the hollow body. An actuator assembly is attached to the hollow body and a sleeve is slideably positioned about the hollow body, with the sleeve moveably attached to the actuator assembly. During operation, the actuator assembly moves the sleeve from a first position that covers the aperture to a second position that un-covers at least a portion of the aperture.

Described is a system for remotely detecting and signalling the open and/or closed state of the shutter (O) of an element (3) for controlling the flow of gas along a gas distribution line (2), comprising an electric switch (17; 18) configured to generate an electrical signal representing at least one of the open and closed states.

A balanced valve trim, a regulator valve with a balanced valve trim, and methods for modifying a regulator valve with a balanced valve trim assembly to accommodate different volume flow rates through the regulator valve are disclosed.