Patent ID: 8893827
Filing Date: 2014-11-25
Classification: E21B,Y10T

Abstract:
1. A drilling apparatus comprising: a hydraulically powered hammer comprising: a piston to impact a drill bit; a shuttle valve to control reciprocation of the piston; an accumulator for hydraulic fluid; and a hammer connection valve at least one drill rod comprising: a first connection valve for connection of the drill rod to the hammer; and a second connection valve for connection of the drill rod to the first connection valve of a like drill rod or to a rotation device wherein the piston and shuttle valve are positioned substantially in-line to the axis of movement of the hammer; the accumulator is positioned proximate to the shuttle valve; and the hammer connection valve, first connection valve and second connection valve comprise at least one poppet valve positioned proximate to a corresponding valve seat; wherein the drill rod also comprises a pressure line for supply of pressurized hydraulic fluid from an external reservoir to the shuttle valve and a return line to supply return hydraulic fluid from the shuttle valve back to the external reservoir and wherein the pressure line and return line form a sealed float n connection with at least one connection valve, allowin relative movement between each of the lines and the valve to allow expansion without fluid loss.