| 摘要 |
<p>An oilfield valve eg. a kelly valve comprises a valve body having threaded connections on each end. A unit handled valve mechanism 40 includes a cage 42 carrying a spring loaded floating valve ball 46. The valve mechanism 40 is placed in and removed from the valve body without the use of special tools. The valve mechanism 40 includes lip type polyseals 52 allowing pressure from below to leak past a lower valve seat so pressure from below causes the valve ball 46 to seal only against an upper seat assembly 48. The only segment of the valve ball in substantial compression is immediately adjacent the upper seat assembly 48. An actuator 38 for the valve fits onto a connector 112 between the actuator 38 and ball 46 in only one manner, so the indicator on the actuator correctly points at the correct indicia on the valve body describing the valve condition, i.e. open or closed. An improved connector between the actuator and the valve ball minimizes the potential of deformation due to abuse. <IMAGE></p> |
