Valve plugs having curved notches are described herein. An example valve plug includes a first section defining a first end, a second section defining a second end opposite the first end, and a third section located between the first and second sections, the third section including a curved notch formed inwardly from a periphery of the third section toward a longitudinal axis of the valve plug defined by the first, second and third sections.

Valve plugs having curved notches are described herein. An example valve plug includes a first section defining a first end, a second section defining a second end opposite the first end, and a third section located between the first and second sections, the third section including a curved notch formed inwardly from a periphery of the third section toward a longitudinal axis of the valve plug defined by the first, second and third sections.

An intermittent air discharge apparatus has a main valve and a pilot valve, the main valve being switched between a discharge state and a discharge stop state. The pilot valve is switched between an air-supply state to supply air to a pilot chamber for air-discharge, and an air-supply stop state. When the pilot valve is switched to the air-supply state, an exhaust passage communicates with the pilot chamber for air-discharge. When the pilot valve is switched to the air-supply state, a supply or exhaust passage allows an air supply passage to communicate with the pilot chamber for air-discharge and a pilot chamber for stopping air-supply; when the pilot valve is switched to the air-supply stop state, communication with the air supply passage is blocked. A flow rate of air from the pilot chamber for air-discharge is set by the exhaust passage, and a flow rate of air from the pilot chamber for stopping air-supply is set by the supply or exhaust passage.

An in-line shutoff valve includes a valve body with an inlet chamber, an outlet chamber, and a poppet seat disposed between the inlet and outlet chambers. A poppet is movably disposed within the valve body and has an open and closed position. The poppet seats against the poppet seat in the closed position, fluidly separating the inlet chamber from the outlet chamber. The poppet is unseated from the poppet seat in the open position, fluidly coupling the inlet and outlet chambers. A manifold with a servo port and a vent port is disposed within the valve body between the inlet and outlet chambers, the vent port being in fluid communication with the servo port to cool valve internal structures when the poppet is in the closed position.

An in-line shutoff valve includes a valve body with an inlet chamber, an outlet chamber, and a poppet seat disposed between the inlet and outlet chambers. A poppet is movably disposed within the valve body and has an open and closed position. The poppet seats against the poppet seat in the closed position, fluidly separating the inlet chamber from the outlet chamber. The poppet is unseated from the poppet seat in the open position, fluidly coupling the inlet and outlet chambers. A manifold with a servo port and a vent port is disposed within the valve body between the inlet and outlet chambers, the vent port being in fluid communication with the servo port to cool valve internal structures when the poppet is in the closed position.

A valve includes a valve body with an annular valve seat having a first central axis, and a valve closure subassembly assembled with the valve body and including an axially movable valve stem and a stem tip attached to the valve stem by a stem connector and including an annular seal portion having a second central axis. When the first central axis is misaligned with the second central axis, the stem tip is pivotable about the valve stem to effect angular adjustment of the annular seal portion of the stem tip into uniform sealing engagement with the annular valve seat when a closing force is applied to the valve stem. The stem connector is configured to resist pivoting movement of the stem tip when the valve stem is in the open position.

A valve includes a valve body with an annular valve seat having a first central axis, and a valve closure subassembly assembled with the valve body and including an axially movable valve stem and a stem tip attached to the valve stem by a stem connector and including an annular seal portion having a second central axis. When the first central axis is misaligned with the second central axis, the stem tip is pivotable about the valve stem to effect angular adjustment of the annular seal portion of the stem tip into uniform sealing engagement with the annular valve seat when a closing force is applied to the valve stem. The stem connector is configured to resist pivoting movement of the stem tip when the valve stem is in the open position.

A valve for use in a tank vessel that includes a valve housing configured to fit into a threaded vent opening of the tank vessel and a sleeve weldment coupled to the valve housing. The sleeve weldment includes a first end configured to protrude into an interior volume of the tank vessel, and the first end is thermally balanced with the interior volume of the tank vessel. The valve also includes a valve plunger configured to be installed within the sleeve weldment. The valve plunger includes a valve bottom configured to seal an opening between the valve bottom and an interior opening of the sleeve weldment. The valve also may include a cam configured to force the valve plunger into the interior of the tank vessel to break the seal between the valve bottom and the interior opening of the sleeve weldment.

A valve for use in a tank vessel that includes a valve housing configured to fit into a threaded vent opening of the tank vessel and a sleeve weldment coupled to the valve housing. The sleeve weldment includes a first end configured to protrude into an interior volume of the tank vessel, and the first end is thermally balanced with the interior volume of the tank vessel. The valve also includes a valve plunger configured to be installed within the sleeve weldment. The valve plunger includes a valve bottom configured to seal an opening between the valve bottom and an interior opening of the sleeve weldment. The valve also may include a cam configured to force the valve plunger into the interior of the tank vessel to break the seal between the valve bottom and the interior opening of the sleeve weldment.

A valve having a balancing function for a fluid distribution system. A valve closing member is movable between a closed position and a fully opened position. An actuation device is provided for changing the position of the valve closing member. A control unit is provided and includes an electronic memory adapted to receive and store an opening limitation value, the opening limitation value being representative of a selected intermediate position between the closed position and the fully opened position of the valve closing member, wherein the control unit controls the actuation device to limit the movement of the valve closing member to positions from the closed position to the selected intermediate position. Also, a valve system and to a method of operating a valve.