| 摘要 |
<p>The silent gas expansion valve has a central inlet pipe with an outer coaxial outlet pipe. the annulus which communicates with the outlet is covered with a perforated plate. The perforated plate is, in turn, covered with a porous membrane. A flexible diaphragm is clamped between flanges and its upper surface is subjected to the control pressure in the space between them. The total area of the cross-section of the holes in the plate is equal to the effective area of flow through the porous membrane. When the gas pressure equals the control pressure the diaphragm is pushed off the porous membrane allowing the gas to flow from the inner tube to the annulus.</p> |
