| 摘要 |
SYSTEMS AND METHODS FOR OPERATING A CIRCULATION VALVE (44) SUCH THAT THE VALVE WILL AUTOMATICALLY CLOSE WITHOUT THE NEED FOR A BALL TO BE DROPPED OR OTHER INTERVENTION FROM THE SURFACE. THE CIRCULATION VALVE IS AUTONOMOUS AND WILL PREFERABLY BE ACTUATED FROM AN OPEN TO A CLOSED POSITION BY A MOTIVE FORCE SUCH AS A POWER SCREW. THE VALVE INCLUDES AN ACTUATOR THAT CAUSES THE VALVE TO CLOSE IN RESPONSE TO PARTICULAR CONDITIONS, SUCH AS THE PASSING OF A PREDETERMINED AMOUNT OF TIME, OR WELLBORE (10) CONDITIONS, SUCH AS PRESSURE, TEMPERATURE OR POSITION. |
