ABSTRACT A feature of reverse circulation pneumatic down-the-hole (DTH) hammer drilling
system is its ability to reduce the emission of respirable dust which is known to be harmful to …

Air reverse circulation (RC) drilling has drawn considerable interest and has been adopted
in tunnel drilling owing to its beneficial features. Cutting transport is a primary concern in RC …

This paper sets forth a geomechanics framework for assessing the energy efficiency of rotary
percussive drilling using the energy criterion, which has been proposed by Victor Oparin for …

The authors address the problem connected with the determination of efficient rotary
percussive drilling techniques with DTH hammers and present estimation criteria for their …

Reverse circulation impact drilling has the advantages of high drilling efficiency and less
dust, which can effectively form holes in hard rock and gravel layer. As integral reverse …

The cluster down-the-hole hammer reverse-circulation drilling technology is an attractive
approach for achieving a high rate of penetration (ROP) through the" small hole drilling …

A reverse circulation Down‐The‐Hole (DTH) hammer drill bit in Casing‐while‐Drilling
(CwD) processes is designed and applied to drilling under complicated formation. The drill …

Down-the-hole (DTH) hammer drilling with reverse circulation is a novel, mobile, high-speed
drilling system suitable for the specific requirements of mine rescue. This technology can be …

The motional dynamics of nuclear magnetic resonance (NMR) logging tools can significantly
influence the measurement performance of such tools. NMR logging is used for geophysical …

Utilizing the Geneva drive mechanism, an inventive retractable drill bit tailored for casing-
while-drilling (CwD) applications was developed. This novel design allows the lower …