Cluster Opening Sleeves for Wellbore

摘要

A downhole sleeve has an insert movable in the sleeve's bore from a closed condition to an opened condition when a ball dropped in the bore engages an indexing seat in the sliding sleeve. In the closed condition, the insert prevents communication between the bore and the sleeve's port, while the insert in the opened condition permits communication between the bore and port. Keys of a seat extend into the bore to engage the ball and to move the insert open. After opening, the keys retract so the ball can pass through the sleeve to another cluster sleeve or to an isolation sleeve of an assembly. Insets or buttons disposed in the sleeve's port temporarily maintain fluid pressure in the sleeve's bore so that a cluster of sleeves can be opened before treatment fluid dislodges the button to treat the surrounding formation through the open port.