Chemical cutting apparatus having selective pressure bleed-off

摘要

A chemical cutting apparatus for use within a well bore is disclosed. The apparatus of the present invention includes a tubular casing adapted to be lowered into a well bore. The tubular casing contains an internal chamber containing a chemical cutting fluid. A remotely operated explosive charge pressurizes the chamber of chemical cutting fluid and simultaneously forces chemical cutting fluid out through a discharge passage and erects a plurality of slips which anchor the tubular casing within the well bore. After a cutting operation has taken place, pressure buildup within the tubular casing which occurs as a result of a clogged discharge passage may be vented or bled off by the selective opening of a second discharge passage, thus preventing undesired engagement of the anchor slips during removal of the apparatus. In a preferred embodiment of the present invention, an interlock is provided which prevents the opening of the second discharge passage prior to ignition of the explosive charge.