Drill string jarring and bumping tool with piston disconnect

摘要: A jarring and bumping tool for a drill string is described. The includes an inner mandrel outer housing telescopically coupled together defining therebetween annular chamber hydraulic fluid. floating piston assembly located in said moved along the by displacing device carried mandrel. vertical strain applied to when use causes lift assembly. pressure of fluid cushions movement until enters enlarged portion cylinder, whereupon released, allowing abutment faces on slam apply upward jar string. When returned downwardly, draws down cylinder arrested. Continued disengage from assembly, other downward bump tool. Since disengaged stationary during bump, wear reduced, cushioning also reduced.