| 摘要 |
<p>"CHOKE FOR DRILLING OR PRODUCTION USE" A choke is provided having a stationary tubular flow nozzle with throttling ports formed through its side wall. A movable tubular throttling ring may be moved over the nozzle to restrict or close the ports. The required liquid-tight seal or shut-off is obtained with annular seal surfaces formed on the nozzle and ring but remote from and upstream of the ports, so that erosion of these seal surfaces, by the high velocity streams passing through the ports, is minimized.</p> |
