A butterfly valve includes a drive unit and a valve unit that are coupled to each other. The drive unit includes a hollow part in which a rod is inserted between a DD motor and an end portion of the drive unit on a coupling side to the valve unit. In the hollow part, a cylindrical magnetic member is placed coaxially with the rod to cover the outer peripheral surface of the rod. A magnetic fluid is filled in a void between the outer peripheral surface of the magnetic member and the inner peripheral surface of the hollow part. The rod is made of a non-magnetic corrosion-resistant alloy.

A valve assembly includes a valve body defining a fluid inlet in fluid communication with a fluid outlet. The valve body has an inner body surface defining an interior chamber extending between the fluid inlet and the fluid outlet. A valve element is disposed within the interior chamber and rotatable through a range of positions relative to the outlet providing a high level of precision control of a fluid flow rate through the valve assembly. A valve seat with a seal is positioned around a valve element. The valve seat is configured to self-adjust its inner radial diameter to correspond to the outer radial diameter of the valve element to maintain a portion of an inner seat surface in contact with an outer valve surface of the valve element through the range of positions.

A body covering a disk in a butterfly valve comprises: an upper body; and a lower body, wherein an inserting space is formed by combining the upper body with the lower body, the disk is inserted into the inserting space, and at least one of the upper body and the lower body includes a framework formed of a metal and a plastic layer formed on the framework.

The present invention discloses a butterfly valve including: a valve body, an inner valve seat, a valve core, a valve stem and at least one positioning ring. The valve body has an inlet end, an outlet end, and an axial passage communicating with the inlet end and the outlet end. A valve stem mounting hole is provided between the inlet end and the outlet end in the valve body. The valve body further is provided with a valve seat mounting portion in the axial passage at a position corresponding to the valve stem mounting hole. The inner valve seat is fixedly mounted to the valve seat mounting portion, which is cylindrical and is provided with radial through hole in the side wall corresponding to the valve stem. the valve core is plate-shaped and mounted in the inner valve seat, a radial through hole is provided therein. The valve stem passes through the valve stem mounting hole, the radial through hole of the inner valve seat and the radial through hole of the valve core. The positioning ring is mounted in the valve body at an axial side of the inner valve seat and form a hermetic connection with the inner valve seat. The butterfly valve of this invention has good tightness

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 method of manufacturing a valve with a corrosion-resistant barrier includes providing a valve body defining a first end, a second end, and a body bore extending from the first end to the second end, the valve body further defining a channel co-annular with the body bore, the channel comprising an outer edge defining a seat retention groove; and thermal spraying a corrosion-resistant barrier over the seat retention groove, the corrosion-resistant barrier defining a first edge and a second edge, the first edge oriented between the seat retention groove and the first end of the valve body, and the second edge oriented between the seat retention groove and the second end of the valve body.

The present invention discloses a butterfly valve including: a valve body, an inner valve seat, a valve core, a valve stem and at least one positioning ring. The valve body has an inlet end, an outlet end, and an axial passage communicating with the inlet end and the outlet end. A valve stem mounting hole is provided between the inlet end and the outlet end in the valve body. The valve body further is provided with a valve seat mounting portion in the axial passage at a position corresponding to the valve stem mounting hole. The inner valve seat is fixedly mounted to the valve seat mounting portion, which is cylindrical and is provided with radial through hole in the side wall corresponding to the valve stem. the valve core is plate-shaped and mounted in the inner valve seat, a radial through hole is provided therein. The valve stem passes through the valve stem mounting hole, the radial through hole of the inner valve seat and the radial through hole of the valve core. The positioning ring is mounted in the valve body at an axial side of the inner valve seat and form a hermetic connection with the inner valve seat. The butterfly valve of this invention has good tightness.

A valve seat includes an annular sealing body defining an inner seat surface and an outer seat surface, the inner seat surface defining an annular seating portion configured to seat with a valve member; and a circumferential sealing rib extending circumferentially about the annular sealing body, the circumferential sealing rib defining a gooseneck portion coupled to the annular sealing body and a bulbous portion coupled to the gooseneck portion opposite the annular sealing body.

A method of manufacturing a valve with a corrosion-resistant barrier includes providing a valve body defining a first end, a second end, and a body bore extending from the first end to the second end, the valve body further defining a channel co-annular with the body bore, the channel comprising an outer edge defining a seat retention groove; and thermal spraying a corrosion-resistant barrier over the seat retention groove, the corrosion-resistant barrier defining a first edge and a second edge, the first edge oriented between the seat retention groove and the first end of the valve body, and the second edge oriented between the seat retention groove and the second end of the valve body.

Example aspects of a valve are disclosed. The valve can comprise a valve body defining a first end, a second end opposite the first end, an inner surface, and an outer surface, the inner surface defining a body bore extending from the first end to the second end and a channel extending radially outward from the body bore, the channel defining a seat retention groove; a metal barrier applied to the inner surface and covering the seat retention groove, the metal barrier defining a first edge and a second edge, the first edge oriented between the seat retention groove and the first end, and the second edge oriented between the seat retention groove and the second end; and a valve seat positioned within the channel.