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.

A valve flap device having at least one valve housing having a shaft comprising a bearing surface and a valve axis, the shaft being rotationally supported about the valve axis by means of the bearing surface in the valve housing. A bearing element having a sliding bearing surface, wherein the bearing surface of the shaft contacts the sliding bearing surface. A bearing housing provided on the valve housing, in which the bearing element is supported at least in the radial direction to the valve axis, wherein the bearing element has an outer surface contacting the bearing housing. The support of the shaft is intended to be sufficiently tightly sealed, even for gaseous media, while simultaneously ensuring precise and statically determinate support. To this end, the bearing element is designed as a separate component coupled to the bearing housing about the valve axis with respect to the circumferential direction, such that the relative position between the bearing element and the bearing housing does not change in the circumferential direction when the shaft is rotated.

A valve assembly having a valve housing, the valve housing defining a passageway. A flapper valve arranged within the passageway is coupled to a rotatable valve shaft. A flexible wall, sealed along opposed edges to the valve housing, is controllable to at least two positions. The first position seals against the flapper valve and the second position releases the flapper valve allowing for ready movement of the valve.

A valve seat device including a valve seat and a seat stiffener, the seat stiffener formed from a non-elastomeric material and positioned on a radially outward-facing surface of the valve seat, an outer diameter of the radially outward-facing surface of the valve seat being greater than an inner diameter of the seat stiffener.

Provided is a slide plate valve, comprising a valve body and a valve core component comprising a valve plate (3) and a support frame (2), wherein at least one support member (4) is disposed on the top portion of the support frame (2) and sleeved with an elastic member (7) thereon, and one end of the elastic member (7) is connected to a pressing plate (5) disposed on a top end of the support member (4), and the other end of the elastic member (7) is connected to a limiting plate (6) slidably disposed on the support member. The slide plate valve avoids the problem of getting stuck.

A butterfly valve for controlling gas flow is disclosed. The butterfly valve may include a valve body, the valve body defining a bore and a shaft configured for rotatable motion with respect to the valve body and including a shoulder. The butterfly valve may further include a disk housed within the bore, operatively coupled with the shaft, and configured to control gas flow through the bore based on a rotational position of the shaft relative to the valve body. The butterfly valve may further include a ball bearing operatively coupled with the shaft and including a ball and a race. The butterfly may further includes a spring configured to provide an axial force on the shaft, the axial force configured to press the shoulder of the shaft against the race of the ball bearing to prevent an outer edge of the disk from contacting an inner wall of the bore.

A butterfly valve for controlling gas flow is disclosed. The butterfly valve may include a valve body, the valve body defining a bore and a shaft configured for rotatable motion with respect to the valve body and including a shoulder. The butterfly valve may further include a disk housed within the bore, operatively coupled with the shaft, and configured to control gas flow through the bore based on a rotational position of the shaft relative to the valve body. The butterfly valve may further include a ball bearing operatively coupled with the shaft and including a ball and a race. The butterfly may further includes a spring configured to provide an axial force on the shaft, the axial force configured to press the shoulder of the shaft against the race of the ball bearing to prevent an outer edge of the disk from contacting an inner wall of the bore.

A sealing arrangement for a valve can include a first seat portion, a second seat portion extending from the first seat portion in a first direction, and an anchor portion extending from the first seat portion in a second direction transverse to the first direction. The anchor portion can include an anchor section having a first sealing surface to provide a first seal within the valve and a convolution section arranged between the first seat portion and the anchor section and including at least one bend that is resiliently compressible in the second direction so that the first seat portion moves in the second direction when the convolution section of the anchor portion is compressed in the second direction.

Flexible seals for process control valves are disclosed. An example disclosed seal includes a seal for use with a butterfly valve. The example seal includes a substantially flexible ring-shaped carrier configured to be moveably fixed within the butterfly valve and to surround a flow control aperture therein. The example seal includes a seal stiffener adjacent the substantially flexible ring-shaped carrier to increase the stiffness of the substantially flexible ring-shaped carrier in a first flow direction. The example seal includes a substantially rigid seal ring to engage an opposing surface.

A valve seat device including a valve seat and a seat stiffener, the seat stiffener formed from a non-elastomeric material and positioned on a radially outward-facing surface of the valve seat, an outer diameter of the radially outward-facing surface of the valve seat being greater than an inner diameter of the seat stiffener.