A butterfly valve seal arrangement in a butterfly valve having a cylindrical flow channel with a wall includes a seal flange, an elastomeric seal, a seal channel, and an annular seal retaining ring. The seal flange extends into the cylindrical flow channel from the wall of the cylindrical flow channel. The seal channel is recessed into the wall of the cylindrical flow channel adjacent to the seal flange. And the annular seal retaining ring includes tabs extending into the seal channel which hold the annular seal retaining ring in the cylindrical flow channel. An elastomeric seal is held in compression in the seal channel and against the seal flange by the annular seal retaining ring, and extends into the cylindrical flow channel forming a seal surface held in compression against a vane seat of a vane in a position perpendicular to a direction of flow.

An exhaust gas recirculation valve device for a vehicle includes: a valve housing having an exhaust gas inlet port and an exhaust gas outlet port; a flap valve rotatably mounted on the valve housing to open and close the exhaust gas outlet port; a valve shaft fitted to penetrate the flap valve and coupled to the flap valve so as to rotate integrally with the flap valve; a lever in which one end of the valve shaft is fitted to penetrate; a spring fixed at the lever and mounted on an exterior circumferential surface of the valve shaft; a bush inserted into the exterior circumferential surface of the valve shaft between the spring and the flap valve in a shaft direction; and a thrust washer installed between the flap valve and the bush.

A butterfly valve includes a valve body with an internal flow passage extending in a direction of a flow passage axis, a disk-shaped valve member supported in the internal flow passage rotatably about a rotation axis perpendicular to the flow passage axis and having a spherical valve seat surface in an outer peripheral portion, an annular recessed portion surrounding the internal flow passage on the side surface of the valve body in a direction of the flow passage axis, and a seat ring attached to the annular recessed portion such that a valve seat portion provided in an inner peripheral edge portion thereof projects into the inner flow passage. The valve seat portion has a triangular cross section and is formed such that a bisector of a vertex angle in the triangular cross section of valve seat portion is perpendicular to a tangential line to the valve seat surface.

A valve seat includes a first end; a second end positioned opposite from the first end; and a body extending from the first end to the second end, the body defining an inner surface and an outer surface, the inner surface defining a main bore extending through the body from the first end to the second end, the main bore defining a main bore axis, the body defining a shaft bore extending from the inner surface to the outer surface, the shaft bore defining a shaft bore axis positioned perpendicular to the main bore axis, the shaft bore defining an inner shaft opening and an outer shaft opening, the body defining a concave seat bearing surface extending around the inner shaft opening.

A welding structure includes, in a cross-section of the first member and the second member when they are seen from an axial direction of the insertion hole, a plurality of welding spots, an outer periphery of the welding spots are each formed with a curve-shaped portion and two side-face portions. When two intersections where the outer side-face portion on the outer periphery of the both-end welding spots and the outer periphery of the second member intersect are defined as a first intersection and a second intersection, a weld angle formed by a first linear line linking the first intersection with a sectional center of the second member and a second linear line linking the second intersection with the sectional center of the second member is set to a first predetermined angle or more.

Flap valves include a valve housing and a flap disc in a flow channel of the valve housing. The flap disc can be pivoted between an open position and a closed position. The flow channel on its outer circumference includes a sealing lip arrangement, which has two elastic sealing lips arranged at a distance from each other in the direction of flow. With the valve disc in the closed position, the sealing lips bear under elastic prestress against the sealing surface of the valve disc to form a seal and thereby form an annular cavity surrounding the sealing surface of the valve disc. Further, with the flap disc in the closed position, the passage of fluid from the high-pressure side in the flow channel to the low-pressure side of the flow channel prevented due to the cross-sectional areas of the two sealing lips of the sealing lip arrangement being inclined or bent towards the inside of the annular cavity.

A valve including: a flow channel and a closure member. A first sealing surface is provided along walls of the flow channel and a second sealing surface is provided along outer edges of a sealing section of the closure member. A rotation axis is offset from the sealing section by a first predetermined distance and from a centerline of the closure member by a second predetermined distance. To ensure smooth operation of the closure member at least one of the first and second sealing surfaces has a non-conical shape that is at least in one area asymmetric with respect to the center axis of the closure member.

A top-loaded rotary valve with elliptical sealing is provided. The valve includes a valve cartridge with a lower cylinder portion having a first flow opening, an upper cylinder portion having a second flow opening, a rotor, and a gasket positioned between respective ends of the lower cylinder portion and the upper cylinder portion. The rotor includes a stem and a disc configured to rotate within the cartridge. The lower cylinder portion and the upper cylinder portion are mated to the gasket along a plane that defines an ellipse along the respective cylinder ends. The disc has perimeter that is similar to the ellipse, and the rotor rotates between a closed position in which the elliptical perimeter of the disc is coincident with the gasket to prevent flow between the flow openings and an open position that permits flow between the flow openings.

A metal seal for a flap valve, is disclosed which has a valve housing with a flow channel, in the flow cross-section of which a valve disk is disposed such that it can be swiveled around a swivel axis between an open position and a shutoff position. The seal has sealing elements, which can be pressed against one another, and which are disposed on the outer circumference of the valve disk and on the inner circumference of the valve housing, and they have at least one annular metal sealing lip, which in the shutoff position bears with elastic preload on an oppositely situated, likewise annular metal mating sealing face. To prevent damage to outer components, the metal sealing lip is produced in an additive method from metal materials having shape, cross-sectional geometry and/or alloy adapted to the different circumferential regions of the metal sealing lip.

A butterfly valve includes a valve body with an internal flow passage, a seat ring attached to an inner peripheral surface of the internal flow passage, a valve stem rotatably supported by the valve body, and a valve element rotatably supported by the valve body via the valve stem. The valve element has an annular outer peripheral edge surface, and includes, at opposite positions in the direction of the rotation axis on the outer peripheral edge surface, two valve-stem openings for the valve shaft to pass therethrough. The outer peripheral edge surface of the valve element includes two annular opening raised portions each extending along the periphery of the corresponding valve stem openings, and peripheral edge raised portions connecting the two opening raised portions, each having a peripheral edge sealing surface extending along a top thereof, and chamfered surfaces inclined and extending along both sides of the peripheral sealing surface.