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.

Valves having seats and counterseats that can be moved by fluid within the valve. In one embodiment, a valve includes a flow control assembly inside a body. The flow control assembly includes a ball rotatable between an open position and a closed position to control flow, a seat installed on the ball, and a counterseat installed in the body. The seat and the counterseat can move radially with respect to the ball and have mating surfaces that engage and seal against one another when the ball is in the closed position. The flow control assembly allows pressurized fluid in the body to cause net forces on the seat and the counterseat that push the seat and the counterseat toward each other when the ball is in the closed position. Additional valve systems, devices, and methods are also disclosed.

A flow control valve includes a valve body having a first section and a second section attached to the first section. A flow control member is positioned within the valve body and a shaft extends through the valve body and is connected to the flow control member to move the flow control member between an open position and a closed position. A sealing gasket is positioned within the valve body and engages the valve body to prevent the flow of fluid between the first section and the second section. The sealing gasket has an annular metallic body having an inner surface and an opposing outer surface, the outer surface defining a primary sealing surface, a groove formed in the outer surface, and an insert positioned within the groove, the insert defining a secondary sealing surface.

A ball valve is provided. The ball valve includes a housing, a ball seat arranged in the housing, a ball member mounted within the housing and being rotatable relative to the ball seat between open and closed positions, the ball seat and ball member defining respective through bores, the ball member including a sealing surface, a bore surface and a leading edge surface extending between the sealing surface and the bore surface, the leading edge surface being configured to cut a body extending at least partially through the valve upon closure of the ball member, wherein said leading edge surface is truncated. The ball member may include a relief region proximate the leading edge surface.

A valve for connection to a pressurized gas cylinder includes a housing including a gas cylinder aperture which is connectable to a gas cylinder, and a housing conduit which extends through the housing from the gas cylinder aperture to one or more inlet/outlet apertures so that the valve is capable of providing fluid communication between the gas cylinder through the housing conduit and the one or more inlet/outlet apertures. A flow control ball within the housing conduit is movable between open and closed positions. Ball seals have sealing surfaces corresponding to a shape of the flow control ball for substantially sealing the flow control ball in the housing conduit. Other features include components for mounting the ball seals though one of the inlet/outlet apertures; components for mounting a stem to the flow control ball including bearings; live ports; a tube which can be removably connectable from the rest of the housing; provision for receiving an EFV and/or a PRD in the valve housing; and at least one of the ball seals and stem bearings comprising polyetherimide or polyaryletherketone.

A top entry trunnion mounted rotary ball valve suitable for safe in-line maintenance, comprising a main valve body having an upstream and a downstream ball seat assembly, the ball seat assemblies further comprising a soft insert seal, a ball seat, a seat retainer and a plurality of compression springs in between the ball seat and the seat retainer. A guiding groove on the cylindrical surface of each of the ball seats, having a first end and a second end at an axial distance equal to or more than the measure of retraction required so as to get the mechanical clearance adequate to remove or assemble the ball member, the angular span between the first end and the second end of the guiding groove can be less than 180 degrees or more than 360 degrees, depending on the overall size of rotary ball valve, in order to be able to manually retract in the ball seats. Each ball seat is retracted in the recess, with the aid of a guide assembly, by using a straight rod, against a force Fc of the compression springs and the mechanical clearance is created between the ball member and the soft insert seal, to remove or assemble the ball member and or any or all components from or inside the valve body. An angle of grove a, which is an angle between the flange and the guide groove, is kept of relatively of low value for big sized valves whence an angular span of guiding groove becomes relatively higher so that the required axial distance, which is equal to or more than the measure of retraction required so as to get the mechanical clearance adequate to remove the ball member, is attainable between the first end of the groove and the second end of the groove, by a Force Ft apply-able by a person of normal physique, and vice versa for a small sized valve. The rotary ball valve cannot be put in operation inadvertently if the ball seats are in retractable or retracted position.

Disclosed is a coolant control valve unit having a sealing structure, the control valve unit including: a rotary valve provided with a valve coolant passage formed from an inner surface to an outer surface of the rotary valve; a valve housing in which the rotary valve is rotatably provided; a fitting coupled to the valve housing, and having a fitting coolant passage; and a sealing unit provided between a front surface of the fitting and the outer surface of the rotary valve, wherein the sealing unit includes: a sealing ring being in contact with the outer surface of the rotary valve; and a rubber ring provided on the front surface of the fitting, and bringing the sealing ring into contact with the outer surface of the rotary valve, wherein the rubber ring has an X-shaped cross-section, with a front groove, a rear groove, an inner groove, and an outer groove.

A ceramic lined valve comprising: i) a valve body (20) having an end connection (50) for coupling the valve in fluidic communication with a fluid flow conduit; v) a flow control member (22) within the valve body; characterized in that the ceramic lined valve further comprising: vi) a lining (30) within the valve body comprising a single piece of ceramic, wherein the lining extends from the flow control member to the end connection, the lining defining a valve seat abutting the flow control member, and vii) a ceramic covering (40) forming a coupling face of the end connection, separate from and juxtaposed to the lining.

A valve sealing arrangement, including a valve body, and a closing member including a closing member contact surface, and a seat, having a center axis, and provided with a sealing portion with a first sealing surface for making contact with the closing member and a back sealing portion with a second sealing surface for making contact with a surface of the valve body. The seat also includes a bellows between the first sealing surface and the second sealing surface wherein the bellows including bellow members wherein adjacent bellow walls form either inwardly open fold or outwardly open fold and wherein one or more of the bellow members extends in a direction that is oblique to the center axis of the seat.

Valves having seats and counterseats with various contours are provided. In one embodiment, a valve includes a body and a flow control assembly inside the body. The flow control assembly includes a ball, a seat installed on the ball, and a counterseat. The ball is rotatable between open and closed positions to control flow through the body and the seat and counterseat include mating surfaces that engage when the ball is in the closed position such that the seat seals against the counterseat along the mating surfaces. Further, the flow control assembly allows pressurized fluid in the body to enter a region between the seat and the ball and a region between the counterseat and the body so as to cause a net force on the seat from the pressurized fluid that pushes the seat away from the ball and against the counterseat when the ball is in the closed position and a net force on the counterseat from the pressurized fluid that pushes the counterseat toward the ball and against the seat when the ball is in the closed position.