A seal ring of a valve element includes a one-end joint forming portion and an other-end joint forming portion. The one-end joint forming portion includes a one-end first contact portion and a one-end second contact portion located on one side of the one-end first contact portion in an axial direction and extending in a circumferential direction beyond the one-end first contact portion. The other-end joint forming portion includes an other-end first contact portion and an other-end second contact portion located on the other side of the other-end first contact portion in the axial direction and extending in the circumferential direction beyond the other-end first contact portion. An inner diameter of the seal ring when the one-end first contact portion separates from the other-end second contact portion is less than an outer diameter of the valve element.

Valve comprising a body (2), a centred butterfly (1), mounted with the ability to rotate inside the body (2) from an open position revealing the passage to a closed position covering said passage, and a seal (3) arranged inside a housing which is delimited by the seat and by a face, opposite the seat in the closed position, of the butterfly, the seat and the face converging towards the inside in the axial direction. The seal (3) moves freely in the housing.

A valve includes a valve body having an input port and an outlet port. The valve body defines a fluid passageway extending between input port and an outlet port. The valve also includes a valve element disposed in the fluid passageway that controls a flow a fluid through the valve body from the input port to the outlet port. One or more of the fluid passageway and the valve control element is coated with a phobic coating.

A valve includes a valve body having an input port and an outlet port. The valve body defines a fluid passageway extending between input port and an outlet port. The valve also includes a valve element disposed in the fluid passageway that controls a flow a fluid through the valve body from the input port to the outlet port. One or more of the fluid passageway and the valve control element is coated with a phobic coating.

A high-pressure self-sealing butterfly valve, which comprises a valve body and a valve shaft, wherein a flow channel and a butterfly plate are arranged in the valve body, a pure metal sealing ring and a pure metal valve seat are sequentially arranged at a portion, on the outer side of the butterfly plate, of the flow channel, a piston cavity is further formed in a flow direction end face of the pure metal valve seat, and an upper valve shaft and a lower valve shaft are arranged at the upper end and the lower end of the valve shaft respectively; an upper end cover assembly and an upper self-sealing assembly are arranged between the end part of the upper valve shaft and the valve body, a lower sealing bottom cover and a lower self-sealing assembly are arranged between the end part of the lower valve shaft and the valve body.

A seal for a butterfly valve includes an end cap with an outer tubular side wall surrounding an inner tubular side wall, both extending in the same direction providing a gap therebetween. At least the inner side wall is made from a resiliently deformable material. The end cap abuts a conduit entrance, and the inner and outer side walls extend therein, the outer side wall abutting an inner surface of the entrance of the conduit. A rotatable pivotal disk mounted inside the inner side wall within the entrance is rotatable between a position where the periphery of the disk engages the inner side wall to seal the entrance and a position where the disk is angled relative to the entrance, opening the entrance so a fluid may pass through the conduit. A butterfly valve assembly and a vacuum cleaner including the seal or the assembly are also disclosed.

There is provided a technique that includes: a gate valve including a movable gate valve plate; and a butterfly valve that is installed at the gate valve plate, has a diameter smaller than those of valve openings configured to be opened or closed by the gate valve plate, and is configured to be capable of being fully closed, wherein the gate valve plate of the gate valve and the butterfly valve are configured to be capable of being driven independently of each other.

An exhaust valve comprises a substantially tubular body extending along an extension axis, a substantially flat flap, and a shaft integral with the flap and rotatable about a rotation axis between a closed orientation and an open orientation. The exhaust valve further includes a first seat suitable for accommodating a first edge of the flap facing the first seat, and a second seat suitable for receiving a second opposing edge of the flap. In each plane passing through the extension axis, a distal end of a profile of a seat is curved in the direction of the opposing edge until the distal end comes into contact with the opposing edge. A distal end of a profile of an edge is curved in the direction of the opposing seat until the distal end comes into contact with the seat.

An exhaust valve comprises a substantially tubular body extending along an extension axis, a substantially flat flap, and a shaft integral with the flap and rotatable about a rotation axis between a closed orientation and an open orientation. The exhaust valve further includes a first seat suitable for accommodating a first edge of the flap facing the first seat, and a second seat suitable for receiving a second opposing edge of the flap. In each plane passing through the extension axis, a distal end of a profile of a seat is curved in the direction of the opposing edge until the distal end comes into contact with the opposing edge. A distal end of a profile of an edge is curved in the direction of the opposing seat until the distal end comes into contact with the seat.

In a double eccentric valve, a valve seat or valve body includes a rubber seal part in which a seat surface or seal surface is formed. An interference between the valve seat and the valve body is made minimum at a position of a rotary-shaft-directional end of the valve body in the radial direction of the valve body which is parallel to an extending direction of the axis of a rotary shaft.