Apparatus and method for forming a window or an outline thereof in the casing of a cased wellbore

摘要

Apparatus for forming a window or the outline of a window in the casing of a cased wellbore comprises thermal means for forming a window or an outline of a window in said casing and locating means for positioning the thermal means in the casing. The thermal means comprises an oxidation chamber (561) having at least one outlet (562), arranged so that reaction materials (565) in the oxidation chamber react to produce sufficient heat to cause a heat jet to exit through the at least one outlet. <IMAGE>