A pressure regulating valve assembly includes: a valve having an upstream side receiving an input flow and a downstream side providing an output flow, an actuator for opening and closing the valve, including partially opening the valve, and a regulator controlling the actuator to open, close or partially open the valve. The regulator includes a sense pressure port, wherein pressure at the port is maintained constant by the regulator. A chamber has a first entry orifice, a second entry orifice and an exit orifice. The first entry orifice is connected to the upstream side, the second entry orifice is connected to the downstream side, and the exit orifice is connected to the port. The exit orifice provides that the pressure at the exit orifice lies between the pressure at the first entry orifice and the pressure at the second entry orifice.

A PRV is provided, comprising an inlet, an outlet, and a pressure regulating system therebetween to maintain a set pressure at the outlet. The PRV further comprises a selection system configured to select between the two working pressures based on the pressure of the fluid at the inlet of the PRV, and to direct the pressure regulating system to maintain the set pressure at the outlet at the selected working pressure. The selection system comprises a pressure-motion transducer for directing the set pressure when in pressure communication with the inlet, and an auxiliary valve having an auxiliary inlet in pressure communication with the inlet and an auxiliary outlet in pressure communication with the pressure-motion transducer. The auxiliary valve is configured to establish pressure communication between its inlet and outlet when pressure in the inlet traverses a predetermined threshold.

A first diaphragm and a second diaphragm are disposed between a valve element and a body, a diaphragm chamber is formed between the first diaphragm and the second diaphragm, the first diaphragm separates a valve chamber from the diaphragm chamber, and the second diaphragm separates the diaphragm chamber from a back pressure chamber. The diaphragm chamber communicates with an output port, the valve chamber and the back pressure chamber communicate with an input port. A difference between an effective pressure receiving area of the first diaphragm and an effective pressure receiving area of the second diaphragm is equivalent to a passage area in a valve seat.

A pressure regulator for gas distribution systems includes: a connection body for connection between an upstream pipe and a downstream pipe, the following elements being defined inside the connection body: an inlet duct an outlet duct, a high-pressure chamber connected to the inlet duct, a low-pressure chamber connected to the outlet duct, a passage opening between the high-pressure chamber and the low-pressure chamber, a movable shutter designed to obstruct the passage opening, components for moving the movable shutter in a controlled manner. The components for moving the movable shutter in a controlled manner include: a first main control head fixed to the connection body and configured to operate the movable shutter through a first control rod, a second auxiliary control head configured to operate the movable shutter through a second control rod fixed to the same movable shutter.

A pressure reduction plant including two or more valve assemblies arranged in parallel and including: pressure reducers for fuel gas from the supply pressure to the delivery pressure; pilot valves to transmit a control pressure to the pressure reducers when the delivery pressure reaches the calibration value of the pilot valves; derivation conduits to transmit the delivery pressure to the pressure reducers, the pilot valves and the pressure reducer devices; command lines to transmit the control pressure from the pilot valves to the pressure reducers. One of the pilot valves is configured with a calibration value greater than the calibration value of all the remaining pilot valves and each command line is configured to communicate with a control line.

A balanced trim pressure regulator includes a valve body having a fluid inlet and a fluid outlet connected by a fluid passageway. An orifice is disposed between the fluid inlet and the fluid outlet. A valve seat is disposed within the fluid passageway. A movable valve plug is disposed within the fluid passageway, the movable valve plug interacting with the valve seat to selectively open or close the fluid passageway. A cage is disposed in the fluid passageway, the cage surrounding the valve plug, and the cage including at least one a balancing passage that fluidly connects the fluid passageway with a balancing chamber.

Control systems include various combinations of pressure regulators, pilots, and pressure stabilizers to provide systems with adjustable deadbands for over pressure protection, adjustable deadbands for under pressure protection, adjustable deadbands for both over pressure and under pressure protection, pressure assisted closure for over pressure protection, pressure assisted closure for under pressure protection, pressure assisted closure for both over pressure and under pressure protection, or spring assisted closure for over pressure and under pressure protection.

In some examples, a pressure reducing valve includes a valve body defining a defining a flow path and a restricting element within the flow path. A sensing element is configured to modify a position of the restricting element in the flow path. A pressure chamber is configured to transmit a force to the sensing element based on the pressure of a fluid within the pressure chamber. An energy accumulator is in fluid communication with the pressure chamber. The pressure reducing valve includes control circuitry configured to enable a fluid to flow into or discharge from the pressure chamber to alter the pressure in the pressure chamber.

Axial gas pressure regulator in which in a housing (01) is axially positioned a balanced nozzle (02), slidingly movably placed in sliding gaskets (23). Nozzle (02) is pressed by spring (10) and extension (03), while a seat (05) with a gasket (07) is mounted opposite to it, which is squeezed between the housing (01) and an outlet flange (04) and in which are performed openings (29). On the upper side of the housing (01) is mounted a carrier (30) of a second housing (21), consisting of a lower part (08) and an upper part (09), between which is squeezed a membrane (22). On the upper and lower side of membrane (22) is placed on each side one plate (33) which are in the central part connected by a support (34) and a tightener (35), and in the center of which the piston (12) is fixed with a performed choking channel (11) in the axis. The piston (12) is by its lower end slidingly movably placed, through a guide (36) and gaskets (24), in lower part (08) of the second housing (21), and by the upper end, through a guide (37) and gaskets (24), it is placed in the upper part (09) of the second housing (21). The piston (12) leans on roller (13) which is by an axle (17) rotatably placed at the end of a first lever (14), which is by its other end articulately connected with a support (30), and by its middle is articulately connected to a second lever (15). The second lever (15) is at its lower end articulately connected to a third lever (16), which is by an axle (18) is slidingly movably placed in the lower part of the carrier (30), while archly bended legs (161) of the third lever (16) comprise the nozzle (02) and, via plates (38), are slidingly movably connected to it.

A control system for regulating fluid flow and pressure downstream a waterworks main valve includes a variable orifice device disposed upstream a pressure reducing pilot. The variable orifice device is in fluid communication with the pressure reducing pilot and a cover chamber of the main valve. Opening and closing the variable orifice device causes the main valve to modulate and the pressure of fluid downstream the main valve to be changed while avoiding pressure oscillations during the transition between pressure setpoints.