Small-size downhole air drill hammers of increased capacity

The authors review key approaches to designing small-size air drill hammers. The approach to increasing impact capacity of air drill hammers by means of buildup of blow frequency is substantiated. The experimentally obtained and compared characteristics of air drill hammers equipped with the heads made of steel and titanium prove feasibility of increasing impact capacity by means of using low density materials. The technology of thermal treatment of a titanium-alloy hammer head is described, and its laboratory testing results are reported.