Mobile drilling apparatus

摘要

An apparatus for drilling boreholes into the earth includes a mobile carrier with a frame that supports an elongated housing. The housing has upper and lower end portions. An drill pipe section holder is positioned at the lower end of a tubular member rotatably mounted in the housing for holding a drill pipe section and rotating it during placement. A plurality of drive wheels carried by the frame transport the housing between upper and lower positions. The wheels are loaded with adjustable compression springs so that extensive pressure can be applied from the drive wheels to the housing for gripping and driving the housing during insertion. A gear train interconnects the driving wheels so that all of the driving wheels rotate at the same rotational speed. Water is supplied to the housing via a bore that communicates with openings and a bore of the tubular member. The tubular member bore conveys the water to multiple sections of drill pipe (i.e. a drill string) connected end-to-end and to a drill bit at the lower end of the drill string.