WALL SECOND ANGLE PRELOCATION ROTARY DRILLING METHOD

摘要

PURPOSE: A wall second angle prelocation rotary drilling method is provided to form a wall in uniform thickness to the wanted depth and to heighten economical efficiency by decreasing the period and cost of earthwork. CONSTITUTION: The wall second angle prelocation rotary drilling method comprises the steps of attaching an auger motor to a drill, attaching a rod, a hammer and a bit to an inner gear, approaching a casing attached with a casing shoe to an outer gear and generating high-pressure air by a compressor, or driving a piston in the hammer by hitting pressure and rotary power of the auger motor, treating a weathering zone with a casing and crushing to the bedrock.