| 摘要 |
<p>An internal diffuser on a diffuser stem is disposed in a bore of a rotary control valve for attenuating vibration in gas service or cavitation in liquid service. The valve has a valve body and a valve element, and the valve element is rotatable with respect to the internal diffuser. The internal diffuser can be rotatable or non-rotatable with respect to the valve body. The valve element has a valve stem, and the internal diffuser can be arranged coaxially with the valve stem, but this is not a necessary requirement. In one embodiment the internal diffuser is positioned in the bore of the valve element, and the diffuser stem is parallel with the valve stem and spaced laterally apart from it. In another embodiment the internal diffuser is located in the bore of the valve outside of the valve element in either an inlet or an outlet passage of the valve body. The diffuser stem has an axis which can be nonparallel with respect to the axis of the valve stem. A valve actuator is provided for rotating the valve element, and where the internal diffuser is rotatable, a diffuser actuator is provided for rotating the internal diffuser. The diffuser actuator can be fixed to a plate securing the valve actuator so that the valve element and the internal diffuser first rotate together before an independent adjustment is made for rotating the internal diffuser. Where the internal diffuser is rotatable with respect to the valve body, the valve actuator and the diffuser actuator can be manipulated by a control system, the control system having inputs, outputs and logic for rotating the valve element and the internal diffuser into desired positions.</p> |
