A valve, which is rotated about a rotational axis, includes a valve outer peripheral portion. The valve outer peripheral portion has a valve inflow port for supplying fluid to a flow passage of the valve outer peripheral portion and valve outflow ports for discharging the fluid from the flow passage. The valve outflow ports include: a main outflow port which is configured to communicate with a whole of a seat opening of a valve seat; and a plurality of intermediate outflow ports, each of which is configured to communicate with a portion of the seat opening. An axial dimension of each intermediate outflow port, which is measured in an axial direction of the rotational axis, is smaller than an axial dimension of the seat opening, which is measured in the axial direction. The axial dimension of each intermediate outflow port is progressively changed in a circumferential direction.

A trunnion ball valve provides a reliable seal when closed, while minimizing or eliminating frictional resistance during rotation of the ball. A pressurization chamber behind the upstream valve seat can be interconnected by one or more pressurization valves with either the upstream or the downstream process fluid. The interconnection can be via a single 3-way valve. When the valve is closed and the ball is fixed in orientation, the pressurization chamber is automatically connected to the upstream process fluid, thereby pressing the seat against the ball and ensuring a reliable seal. While the ball is being rotated, the pressurization chamber is automatically connected to the downstream process fluid, thereby substantially eliminating valve seat friction. Connection to the downstream process fluid can include connection to a small space in front of the upstream seat. An electronic controller can control both valve stem rotation and the pressurization valves.

A ball valve system includes a body having an upstream end and a downstream end and a ball within the body between the upstream end and the downstream end, the ball being rotatable about a vertical axis to move between a closed position and an open position. The ball valve assembly includes a stem movable in an actuation direction substantially parallel to the vertical axis, the stem including a recess at a proximal portion of the stem, a guiding member extending within the recess of the stem, the guiding member being configured to prevent rotation of the stem or cause rotation of the stem, and a lubrication port in fluid communication with the recess.

An air release structure of an integrated flow control mechanism includes a flow control housing, a radiator nipple provided on an upper portion of the flow control housing and forming a bypass passage portion together with the flow control housing, a float provided in the bypass passage portion and an elastic member to support the float elastically and to selectively open the bypass passage portion.

A sealing device includes: a housing; a seal ring configured to be axially displaceably inserted along an inner circumference of the housing, the seal ring including a front-end surface and a rear-end surface which defines packing mounting space; a packing configured to establish sealing between the housing and the seal ring, the packing being disposed in the packing mounting space; and spring means disposed on the rear-end surface side of the seal ring to elastically bias the seal ring toward the front-end surface side.

A ball valve including a ball defining a bore therein, and a trunnion arm articulated with the ball via a trunnion, the trunnion arm disposed on a resilient member allowing resilient movement of the trunnion arm pursuant to load on the ball.

A control valve assembly includes a valve body defining an inlet, an outlet and a fluid flow pathway therebetween. A ball valve is positioned within the fluid flow pathway and includes a rotatable ball having an inlet opening, an outlet opening and a flow pathway therebetween, an upstream seat ring positioned at an inlet side of the ball, and a downstream seat ring positioned at a downstream side of the ball, the seat rings being configured to substantially seal off fluid flow between upstream and downstream sides of the ball except through the ball fluid flow pathway. At least one of the upstream and downstream seat rings is a dynamic sealing seat ring. A retainer ring is positioned between the dynamic sealing seat ring and a portion of the rotatable ball to substantially prevent deformation of a portion of the dynamic sealing seat ring in a direction toward the ball.

A ball valve structure includes a valve body having a valve chamber therein. A valve ball is accommodated in the valve chamber. The valve ball defines a flow hole therein. Two gaskets are in close contact with two opposite side surfaces of the valve ball, so that the valve ball can rotate around a fixed point in the valve chamber. One side of one of the two gaskets abuts against a washer and a compression spring, so that the gasket is elastically pressed against a surface of the valve ball. A valve stem is connected to the valve ball through the valve body for driving the valve ball to rotate, enabling the flow hole to be opened.

A valve device includes: a ball valve having a ball face shaped in a convex spherical surface; and a valve seat having a seat face shaped in a concave spherical surface. The seat face is pressed onto the ball face. The ball valve is rotated to open a valve by communicating a valve opening defined in the ball valve and a seat opening defined in the valve seat with each other, and to close the valve by stop the communication. A diameter of the seat opening Φ2 is smaller than a diameter of the valve opening Φ1. A curvature radius of the ball face R1 is smaller than or equal to a curvature radius of the seat face is R2.

A valve (10) in accordance with an embodiment of the present invention includes a body (1) having a space in which a stem (3) and a ball (4) are housed, wherein an inner lid body (60) fixing the ball (4) in the space liquid-tightly partitions the space into a part in which the stem (3) is housed and a part in which the ball (4) is housed.