REVERSE CIRCULATION DRILL

摘要

PROBLEM TO BE SOLVED: To provide a reverse circulation drill capable of performing efficient excavation work with reduced failure. SOLUTION: A suction pump unit 15 having a pump body for sucking up muddy water in an excavation hole, is directly joined to the lower end of a kelly-bar 13. Adjusting work for making a drill 1 vertical to the ground is facilitated by positioning the drill 1 in two places of a holder 21 with an arm expandable in the horizontal direction to a mast 2 and a rotary head 14. A stone removing device 16 is arranged under the suction pump unit 15, to remove stones and gravel included in the muddy water discharged on the ground. COPYRIGHT: (C)2006,JPO&NCIPI