DRILLING MACHINE AND DRILLING METHOD OF SHAFT

摘要

A conical piece(11) is attached on the top part of the pile venting pipe(1) to guide the punched remains to be flowed into the lower part of the pile venting pipe. Further on the lower part of this conical piece(12), the top part is fixed, having the plural arms(12) arranged in the part where the circumference of the pile venting pipe(1) is equally divided, thereby the plural cutters(14) from the fixed bracket(13) are installed to be capable of being folded by the pivot(15).