Double piston in-the-hole hydraulic hammer drill

作者： Ryszard J. Puchala

DOI:

关键词: Valve timing 、 Piston 、 Drill string 、 Engineering 、 Angle seat piston valve 、 Axial piston pump 、 Radial piston pump 、 Hammer drill 、 Piston pump 、 Mechanical engineering

摘要: An in-the-hole hydraulic hammer drill of the type having an inlet passageway for fluid and connectible to a drill string providing a source of pressurized fluid, and having pistons capable of providing downwardly directed impacts onto anvils solidly connectible to a drill bit, and having valves operated automatically by movement of the pistons to provide a continuous cycle of operation. The pistons include an upper piston and a lower piston, each capable of impacting respective upper and lower anvils solid with the drill bit, and the valves …