摘要 |
<p>A low-noise rotary control valve includes a valve body (10) and a rotatable ball (12). An upwardly extending diverter (28) is positioned in the entry flow passage (15) of the ball (12). A downwardly extending diverter (30) is disposed on the leading edge of the upper half of the valve (12). The diverters (28, 30) provide a small impedance to flow when the valve is in the full open posi- tion, but provide a tortious path for fluid flow when the valve is partially closed. The tortious path inhibits vortex formation re- sulting in reduced noise and vibration. A third impediment (32) in the outflow passage (16) extends upwardly from the valve and inhibit vortex formation downstream of the valve.</p> |