A method for controlling a system pressure within a closed system includes sending a signal to a pressure control valve corresponding to a pressure set point and actuating the pressure control valve to vary a pilot pressure of a control fluid contained within a pressure control line that is fluidly connected to a pressure regulator. A diaphragm of the pressure regulator is disposed between the pressure control line and a system line and acts on a fluid with the system line to modify the system pressure.

A valve is equipped with a displacement amount regulating mechanism (for example, flow rate control device). An abutment member of the displacement amount regulating mechanism protrudes inside a pilot chamber and faces an upper end surface of a valve main body portion of a valve element. When the valve element (the valve main body portion) is separated from a valve seat to bring the valve into an open state, the abutment member is brought into abutment on the upper end surface of the valve main body portion. This abutment regulates the displacement of the valve element.

A method of collecting data in a field device includes receiving indications of variables for which data is collected, receiving indications of trigger events to trigger collection of data, receiving threshold values associated with each of the trigger events, monitoring the trigger events, and initiating data collection when at least one of the trigger events crosses one the threshold values associated with the corresponding trigger event. A method of tuning a PID controller in a field device includes setting a limited range for selecting a value for a control parameter of the PID controller, selecting the value of the control parameter, wherein the selected value is constrained to be within the limited range, transmitting the selected value to the field device, obtaining, from the field device, a measurement of a response of the field device to a setpoint change, and displaying the obtained response measurements to a user.

A pilot pressure supply solenoid valve (36) is disposed in a flow path connecting an inlet port (16) and a pilot chamber (48), and a pilot pressure discharge solenoid valve (38) is disposed in a flow path through which a pressure fluid in the pilot chamber is discharged to the exterior. A flow path, through which the pressure fluid that has passed through a supply valve (26) is discharged to the exterior, is not provided.

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.

A pressure regulator comprises a primary fluid inlet for connection to a source of high pressure fluid, a fluid outlet for connection to a space to receive the high pressure fluid, a convergent-divergent nozzle having an upstream convergent section, a throat and a downstream divergent section, the primary fluid inlet being in fluid communication with the convergent section of the nozzle; and an outlet pipe having an upstream end arranged around but radially spaced from the outlet of the divergent section of the nozzle, the outlet pipe arranged to receive fluid flow from the outlet of the divergent section of the nozzle and conduct the fluid flowing from the nozzle to the fluid outlet.

Adjustment and remote control system with a pressure regulator for irrigation systems to regulate the water pressure at the outlet, and consequently its flow, being crucial to assure the uniformity and the quantity of water as applied. In the adjustment and remote control system for pressure in irrigation systems, the electronic control board is informed of the target pressure at the outlet of the pressure regulator as disclosed in this document; it reads the current pressure of the adjustment and control system by means of the electronic pressure sensor and, if the pressure is lower than the target, a solenoid valve for pressure increase is activated, using the pressure generated by a pressure generator in any given fluid, and, if the pressure is higher, that pressure is reduced.

A solenoid valve system includes a supply solenoid valve, a plurality of exhaust solenoid valves, and a valve control section controlling opening and closing operation of the supply solenoid valve and the plurality of exhaust solenoid valves using PWM or PFM. The plurality of exhaust solenoid valves are disposed in parallel with each other. The supply solenoid valve and the plurality of exhaust solenoid valves have substantially identical flow rate characteristics. The number of the plurality of the exhaust solenoid valves is twice the number of the supply solenoid valve.

A pressure regulator includes an outlet pressure sensor, loading and unloading electromagnetic valves, and a regulator control circuit operatively connected to the loading and unloading electromagnetic valves and configured to pilot the loading and unloading electromagnetic valves to cancel an error signal given by a difference between an inlet signal corresponding to a desired outlet pressure and a feedback signal provided by the outlet pressure sensor. The pressure regulator includes an engaging current analysis circuit to detect and store reference characteristics of the engaging current of the solenoid of the loading electromagnetic valve in a stable inlet pressure condition, monitor the engaging current to detect any variation of its characteristics with respect to the corresponding reference characteristics, and, in the event of variation, provide a pilot modulation signal to at least one of the loading or unloading electromagnetic valves or a pressure variation signal to the regulator control circuit.

A control line stabilizer includes a body defining an inlet chamber, an outlet chamber, a passageway connecting the inlet chamber and the outlet chamber, a first seat, and a second seat. A disc is disposed in the passageway and is movable between a first closed position, in which the disc engages the first seat, an open position, in which the disc is spaced away from the first seat and the second seat, and a second closed position in which the disc engages the second seat. A first spring is disposed in the outlet chamber and is operatively coupled to the disc. A second spring is disposed in the inlet chamber and is operatively coupled to the disc. The disc restricts fluid flow through the passageway by moving to the first closed position and by moving to the second closed position.