摘要 |
A fluid control device, such as a valve, having a cage composed of a rolled perforated strip with the perforations so arranged as to provide elongated energy dissipating flow passageways with abrupt turns creating a drag and pressure drop on the fluid without generating noise. The strip is coiled around itself into a plurality of layers with communicating overlying perforations offset from each other so that streams of fluid passing through the cage must make a number of turns. |