| 摘要 |
A valve assembly comprises: a valve body including a passageway through which a first gas can be transmitted through the valve assembly; a valve flow control element movable relative to the valve body between an opened position wherein flow through the passageway is at a maximum flow, and a closed position wherein flow through the passageway is at a minimum flow, the valve flow control element is shaped so that a control gap is provided between the valve body and valve flow control element through which the first gas can flow, and the dimensions of the control gap vary depending on the position of the valve flow control element relative to the valve body; and a gas injector arrangement for selectively injecting a second gas into the control gap when the valve assembly is used to control the flow of the first gas through the passageway. The injection of the second gas when the valve flow control element is at or near its closed position helps minimize condensate being deposited on the valve flow control element, as well as reduce the closed conductance of the valve. |
