According to various aspects of the disclosure, a valve assembly for a vacuum chamber housing may have: a valve housing, which has a substrate transfer gap; a valve flap, which is mounted so as to be rotatable about an axis of rotation, thus enabling said flap to be rotated into a first position and into a second position, wherein the axis of rotation is arranged in the substrate transfer gap, and wherein the substrate transfer gap is extended longitudinally along the axis of rotation; wherein the valve flap closes the substrate transfer gap in the first position and is arranged adjacent to the substrate transfer gap in the second position.

A surgical access assembly includes a cannula, a valve housing attached to the cannula, and a valve assembly positioned in the valve housing. The valve assembly includes a centering mechanism with a hoop and fingers, a ring with a flange at one end of the ring, a retainer having first and second discs, a guard having a frame and flaps attached to the frame, and a seal with petals attached to a support. The guard is at least partially disposed in the first disc and the seal is at least partially disposed in the second disc.

A surgical access assembly includes a cannula, a valve housing attached to the cannula, and a valve assembly positioned in the valve housing. The valve assembly includes a centering mechanism with a hoop and fingers, a ring with a flange at one end of the ring, a retainer having first and second discs, a guard having a frame and flaps attached to the frame, and a seal with petals attached to a support. The guard is at least partially disposed in the first disc and the seal is at least partially disposed in the second disc.

A cylindrical valve assembly, including: a housing defining a port, an interior volume, and an interior surface; a lip structure disposed about the periphery of the port, wherein the lip structure protrudes into the interior volume past the interior surface of the housing; and a valve door defining an exterior surface disposed concentrically within the housing, wherein the valve door is configured to move from an open configuration in which it does not obstruct the port to a closed configuration in which it does obstruct the port, and wherein, when the valve door is in the closed configuration, the exterior surface of the valve door is in contact with the lip structure and not the interior surface of the housing. Optionally, the lip structure is provided by an insert structure that is disposed through the port. Optionally, an end of the insert structure opposite the lip structure includes a velocity stack. Optionally, a plurality of dimples are manufactured into the exterior surface of the valve door.

A cylindrical valve assembly, including: a housing defining a port, an interior volume, and an interior surface; a lip structure disposed about the periphery of the port, wherein the lip structure protrudes into the interior volume past the interior surface of the housing; and a valve door defining an exterior surface disposed concentrically within the housing, wherein the valve door is configured to move from an open configuration in which it does not obstruct the port to a closed configuration in which it does obstruct the port, and wherein, when the valve door is in the closed configuration, the exterior surface of the valve door is in contact with the lip structure and not the interior surface of the housing. Optionally, the lip structure is provided by an insert structure that is disposed through the port. Optionally, an end of the insert structure opposite the lip structure includes a velocity stack. Optionally, a plurality of dimples are manufactured into the exterior surface of the valve door.