A valve and coupling for joining pipe elements has a valve body captured in a central space defined by a plurality of coupling segments attached to one another end to end. The inner surface of the valve body defines a bore. A liner on the inner surface surrounds the bore and forms a seal with a valve closing member. Circumferentially arranged projections on the segments engage and center the valve body within the central space. The liner has lobes that extend axially in opposite directions. The lobes are compressed between the segments and the pipe elements to form a fluid tight seal when connection members are tightened to draw the segments toward the central space and into engagement with the pipe elements.

A valve includes an annular body defining a body bore. An annular valve seat is positioned in the body bore and an annular groove is defined in a portion of the annular sealing surface. A rotatable valve element is positioned in the body bore. With the valve element in a closed and an unpressurized condition, the annular groove is deformed and a first groove gap is defined in the annular groove adjacent to the first disc face and a second groove gap is defined in the annular groove adjacent to the second disc face. With the valve element closed and in a pressurized condition, the annular groove is deformed and a third groove gap is defined in the annular groove adjacent to the first disc face. A volume of the third groove gap is greater than a volume of the first groove gap and second groove gap.

A valve includes: a valve body defining a shaft bore therethrough, the shaft bore defining an axis extending through the valve body; a valve shaft positioned within and configured to rotate within the shaft bore of the valve body, the valve shaft including a shaft shoulder defining a shaft shoulder surface facing upward; a top cap secured to the valve body, the top cap including a bore shoulder defining a bore shoulder surface facing downward, the bore shoulder surface facing the shaft shoulder surface; and a seal positioned between the top cap and the valve body, the seal configured to seal against leakage from between the valve body and the valve shaft.

A valve includes: a valve body defining a shaft bore therethrough, the shaft bore defining an axis extending through the valve body; a valve shaft positioned within and configured to rotate within the shaft bore of the valve body, the valve shaft including a shaft shoulder defining a shaft shoulder surface facing upward; a top cap secured to the valve body, the top cap including a bore shoulder defining a bore shoulder surface facing downward, the bore shoulder surface facing the shaft shoulder surface; and a seal positioned between the top cap and the valve body, the seal configured to seal against leakage from between the valve body and the valve shaft.

A valve includes an annular body defining a body bore. An annular valve seat is positioned in the body bore and an annular groove is defined in a portion of the annular sealing surface. A rotatable valve element is positioned in the body bore. With the valve element in a closed and an unpressurized condition, the annular groove is deformed and a first groove gap is defined in the annular groove adjacent to the first disc face and a second groove gap is defined in the annular groove adjacent to the second disc face. With the valve element closed and in a pressurized condition, the annular groove is deformed and a third groove gap is defined in the annular groove adjacent to the first disc face. A volume of the third groove gap is greater than a volume of the first groove gap and second groove gap.

A valve assembly can include a valve body, a seat, and a seat cover. In one aspect, the valve body can include an inner surface and an outer surface. The inner surface can define a body bore and a valve body groove having a bottom groove surface. The seat can include an inner surface defining a seat bore and an outer surface defining a seat alignment rib configured to be positioned in the valve body groove. In one aspect, the valve body groove can define a deformation gap between the bottom groove surface and an outer surface of the seat alignment rib. The seat cover can include an inner surface defining a seat cover bore. In one aspect, the seat cover can be mounted on the seat with an outer surface of the seat cover facing the inner surface of the seat.

A valve includes: a valve body defining a shaft bore therethrough, an axis of the shaft bore defining a vertical axis; a valve shaft positioned within and configured to rotate within the valve body; a valve disc coupled to the valve shaft and positioned within the valve body, the valve disc configured to rotate within the valve body between an open position and a closed position; and a valve seat positioned within the valve body, the valve seat including an outer surface in contact with the valve body and an inner surface in contact with the valve disc, the inner surface of the valve seat defining a sealing ridge extending radially inward with respect to the vertical axis, the sealing ridge having an annular shape about the valve shaft, the sealing ridge concentric with the valve shaft.

A seat ring for a butterfly valve provided at an inner circumferential surface of a valve body so as to create a seal between the inner circumferential surface of a valve body and the valve disc when closing the valve, and a sealing projection continuously protruding inwardly provided between a pair of bosses formed around a pair of opposite valve stem holes for inserting valve stems positioned radially outwardly of a flow passage direction. The sealing projection consists of a contact surface and an adjacent semi-elliptic surface, wherein the contact line of the contact surface and top portion of the adjacent semi-elliptic surface is a semi-elliptic edge displaced by an offset h from a plane defined by a vertical valve centerline and a transversal valve centerline in disc closing direction.

A valve device includes a shaft, a valve body, and a housing including a valve opening. An outwardly facing surface of the valve body is out of contact with the housing and a valve-facing surface is in contact with the housing in a fully closed state in which the valve body closes the valve opening. A valve seal surface includes a first valve seal surface protruding in a valve closing direction and a second valve seal surface recessed in a valve opening direction. A first seal distance in a radial direction from an outer diameter end of the first valve seal surface to a rotation axis is shorter than a second seal distance in the radial direction from an outer diameter end of the second valve seal surface to the rotation axis. The first valve seal surface and the second valve seal surface each have at least a curved surface.

A vacuum pressure control apparatus includes an annular elastic seal member formed with a valve seat, and a doubly eccentric butterfly valve element configured to come into contact or separate from the valve seat. The vacuum pressure control apparatus is to be placed on a pipe connecting a vacuum chamber and a vacuum pump. The vacuum pressure control apparatus is configured to rotate the butterfly valve element in a first direction from a first valve closed position corresponding to an initial state to change vacuum pressure in the vacuum chamber. The vacuum pressure control apparatus further includes a control unit configured to rotate the butterfly valve element in a direction opposite to a first direction so that the butterfly valve element is moved to a second valve closed position different from the first valve closed position.