An operating structure of a pilot-operated solenoid valve is provided. The pilot-operated solenoid valve includes a valve body having a main valve orifice and a pilot valve orifice to open and close the main valve orifice. The pilot valve orifice communicates with an accommodating chamber of the valve body. The operating structure includes a knob, an adjustment rod, and a water stop nut. The knob is positioned and fitted to an opening of the accommodating chamber. The adjustment rod is hermetically fitted in the accommodating chamber. One end of the adjustment rod is threadedly connected to the knob, and the other end of the adjustment rod is connected to the water stop nut. The adjustment rod is driven to move axially by rotation of the knob for driving the water stop nut to control the opening and closing of the main valve orifice.

A valve override assembly, comprising: a housing comprising a first portion including a cavity and a second portion. The first portion and the second portion arranged along an axial direction. A core arranged at least partially within the cavity of the first portion of the housing, wherein the core is movable with respect to the housing along the axial direction and comprises a first engagement portion. An override member arranged at least partially within the second portion of the housing such that the override member is movable with respect to the housing along the axial direction.

An inflation valve is provided and includes a valve defining main and command cavities and including first and second valve portions and a valve seat defining an outlet, a poppet disposed in the main cavity and including first and second rods to engage with the first valve portion and to extend through the valve seat and the second valve portion, respectively, and a piston disposed in the command cavity and a solenoid valve. The solenoid valve normally prevents main cavity-command cavity fluid flow to engage the poppet with the valve seat by fluid pressure acting on the poppet in the main cavity and permits the main cavity-command cavity fluid flow when energized to disengage the poppet from the valve seat by balanced fluid pressure acting on the poppet in the main cavity and on the piston in the command cavity to permit main cavity-outlet fluid flow.

An inflation valve is provided and includes a valve defining main and command cavities and including first and second valve portions and a valve seat defining an outlet, a poppet disposed in the main cavity and including first and second rods to engage with the first valve portion and to extend through the valve seat and the second valve portion, respectively, and a piston disposed in the command cavity and a solenoid valve. The solenoid valve normally prevents main cavity-command cavity fluid flow to engage the poppet with the valve seat by fluid pressure acting on the poppet in the main cavity and permits the main cavity-command cavity fluid flow when energized to disengage the poppet from the valve seat by balanced fluid pressure acting on the poppet in the main cavity and on the piston in the command cavity to permit main cavity-outlet fluid flow.

A butterfly valve assembly includes a butterfly element configured to control fluid flow through a main conduit and a manual override operable to lock the butterfly element in a fully open position or a fully closed position.

A pneumatic trip valve that may include a valve structure, a switch plate air path and an internal check valve. In various aspects, the pneumatic trip valve may be connected to a valve positioner, an actuator, or a combination thereof to control the operation of a fluid process control valve. In operation, the Pneumatic trip valve acts to put the actuator in a preset fail-safe position when the actuator loses sufficient pressure or communication from a main air supply, stored pressurized air from an actuator air reservoir, and/or an external air reservoir.

A pneumatic trip valve that may include a valve structure, a switch plate air path and an internal check valve. In various aspects, the pneumatic trip valve may be connected to a valve positioner, an actuator, or a combination thereof to control the operation of a fluid process control valve. In operation, the Pneumatic trip valve acts to put the actuator in a preset fail-safe position when the actuator loses sufficient pressure or communication from a main air supply, stored pressurized air from an actuator air reservoir, and/or an external air reservoir.

Various embodiments include an actuator comprising: a drive element; a transmission section; an actuating element mechanically actively connected to the drive element through the transmission section; a reset spring exerting a closing force on the actuating element; and a coupling device providing a mechanically active connection between the reset spring and the transmission section. The coupling device is configured to be brought into a first coupling state and a second coupling state. With the coupling device in the first coupling state, the reset spring exerts the closing force on the actuating element in a first closing direction. With the coupling device in the second coupling state, the reset spring exerts the closing force on the actuating element in a second closing direction. The first closing direction and the second closing direction are different.

Various embodiments include an actuator comprising: a drive element; a transmission section; an actuating element mechanically actively connected to the drive element through the transmission section; a reset spring exerting a closing force on the actuating element; and a coupling device providing a mechanically active connection between the reset spring and the transmission section. The coupling device is configured to be brought into a first coupling state and a second coupling state. With the coupling device in the first coupling state, the reset spring exerts the closing force on the actuating element in a first closing direction. With the coupling device in the second coupling state, the reset spring exerts the closing force on the actuating element in a second closing direction. The first closing direction and the second closing direction are different.

To prevent a defect in which particles such as impurities flow into a liquid that flows in from an inlet flow path and discharged from an outlet flow path. Provided is a suck-back valve including: a housing part; a valve element part; a diaphragm part; an open-close mechanism that brings the valve element part and a valve seat part into contact or separates the valve element part and the valve seat part from each other to switch between a closed state and an open state; and a suck-back mechanism that moves the diaphragm part in a direction in which the diaphragm part separates from the valve seat part to increase a volume of a valve chamber. The valve element part and the diaphragm part are molded integrally, the open-close mechanism is disposed in an adjacent space, and the valve element part and the open-close mechanism are coupled in the adjacent space.