Factors Influencing the Design and Application of Downhole Drills

CIM Bulletin, 1965

John Knox Manager, Rock Drill & Portable Compressor Div., Canadian Ingersoll-Rand Company Ltd., Montreal, Que.

The object of this paper is to present an analysis of the major problems encountered both in the design and application of downhole drills. Particular reference is made to design features governed by: physical size limitations; metallurgical material standards; physical operating environment; range of commercial materials to be drilled; high power output required, coupled with simplicity from the operating and maintenance viewpoint; and bit design. The history of attempts to develop downhole drills is discussed, and representative mechanical configurations are illustrated. The general design and application aspects of the different types are commented on. The application of this drill type in various commercial fields, such as (a) oil-well drilling, (b) open-pit mining and (c) underground mining, is discussed, along with the limitations presently imposed by the commercial state of the art in the manufacture of accessory equipment; e.g., drill rods, air compressors, mountings, etc. Suggestions on the possible future direction of the development and application of this tool are put forth.
Keywords: Air, Applications, bit shank, Ingersoll-Rand Company, open-pit, piston, tungsten carbide, Bits, Design, Drill, Drilling, Drills, Materials, Pressure