DOWNWARD ENERGIZED MOTION JARS

摘要

An apparatus for dislodging stuck tools downhole, which includes a tool body; a mandrel (102) moveable within the tool body (101); a spring member (68) for allowing the mandrel (102) to move with jarring force within the tool body (101) when actuated; actuating fluid (119) allowing the mandrel to travel a portion of t he distance in a controlled manner, and at a predetermined point , accelerate its travel to provide a jarring force against th e tool body (101); wherein the actuating fluid (119) includes a first and second volumes of fluid (120, 121) through which a portion of the mandrel (102) travels; the first volume (120) providing controlled travel, and the second volume (121) allowing accelerated travel of the mandrel (102).