Method and apparatus for controlling tool access to a lateral wellbore

摘要

A subterranean structure for controlling tool access to a lateral wellbore (18) extending from a wellbore (10). The subterranean structure comprises a bushing (16) that is located in the wellbore (10) and proximate an opening to the lateral wellbore (18) and that has an access window (14) therethrough for allowing access by a tool to the lateral wellbore (18) through the opening. The bushing (16) further has a slidable access control device (12) coaxially coupled thereto. Also included is a shifter (70) that is engageable with the slidable access control device (12) to cause the slidable access control device (12) to slide between an open position wherein a tool is allowed to pass through the window (14) and the opening and into the lateral wellbore (18) and a closed position wherein the tool is prevented from passing through the window (14) and the opening and into the lateral wellbore (18). <IMAGE>