MULTI-STAGE HYDRAULIC FRACTURING TOOL AND SYSTEM WITH RELEASABLE ENGAGEMENT

摘要

The invention relates to a multi-stage hydraulic fracturing tool and systemfor controllablyexposing selected locations along a wellbore to a pressurized fluid. Thesystem includes acasing having one or more ports, one or more actuation members which traveldown a borehole,and one or more sliding sleeves which initially cover some of the ports andare movable using amating actuation member to uncover those ports. The system further comprises astopmechanism to contact the sliding sleeve member after the sliding sleeve memberhas moved afirst distance downhole under a first predefined amount of force, and arelease mechanism tocause the actuation member to disengage from the sliding sleeve member releaseunder asecond predetermined amount of force.