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U.S. Department of Energy
Office of Scientific and Technical Information

Mobile drilling apparatus

Patent ·
OSTI ID:5820261
A drill assembly is described comprising a mobile support means, a mast positioned on the support means, a reciprocally operable drill head and a hydraulic cylinder system supported by the mast and operable to move the drill head. The system comprises lower hydraulic cylinder rigidly connected to the mast, an upper cylinder movable relative to the mast, a lower piston movable within the lower hydraulic cylinder, an upper piston movable within the upper cylinder, a piston rod connected to the lower and upper pistons and a tube surrounding the upper cylinder and connected thereto, the drill head is connected to a lower portion of the tube.
Assignee:
Bralorne Resources Limited, Calgary
Patent Number(s):
US 4703812
OSTI ID:
5820261
Country of Publication:
United States
Language:
English