| 摘要 |
. A packer assembly is provide suitable for multiple setting and unsetting operations in a well bore during a single trip to seal the annulus between the interior walls of the well bore and a tubing string. The packer Is set by dropping a metal ball which plugs the passageway through the tubing string, such that tubing pressure may thereafter be increased to inflate the packer. A sleeve is axially movable within a control sub from a ball stop position to a ball release position, and has a cylindrical-shaped interior surface with a diameter only slightly greater than the ball. Collet fingers carried on the sleeve are radially movable from an inward position to an outward position to atop or release the ball as a function of the axial position or the sleeve. Fluid flow through the tubing string is thus effectively blocked when the sleeve is in the ball stop position because of the close tolerance between the sleeve and the ball, while the ball is freely released from the sleeve and through the packer assembly when the sleeve is moved to the ball release position. |
