Rotary Boring-Drill.
Description:
Patent for a rotary boring-drill that can easily be assembled or disassembled without the aid of a special tool, is equipped with removable cutters, has clearance between the cutters to prevent material becoming packed around them, and is arranged to mix material disintegrated by the cutters into a mud.
Date:
August 28, 1917
Creator:
Hughes, Howard R.
Item Type:
Refine your search to only
Patent