Other

Boart Longyear Inc.

Epiroc Drilling Tools Aktiebolag

Yao, James, Jing

James Jing Yao

Sverker Hartwig

Alexander Beronius

Thomas ÖSterholm

An internally threaded bit for percussion drilling is provided, which has thread roots wider than the thread crests. A single drill bit, configured according to the present invention, can be connected to a variety of rods, having differing crest widths in their male threads. The invention enables the service life of the rods to be optimized to suit the drilling conditions at hand, without the need to manufacture and keep in inventory a correspondingly large variety of drill bits. The bit of the invention exhibits a reduced rate of ringing off, and can accept drill rods having a range of crest widths.

Threaded coupling for percussion drill bit

A drill rod for a drill string has a thread at each end and is connected to an adjacent rod by a sleeve. The threads on the sleeve and rod are configured to reduce stress concentrations and provide sacrificial wear on the sleeve. The thread has a single start with a part circular root and the wear volume on the sleeve is less than that on the rod. The outer diameter of the rod is at least twice that of the inner bore.

Straight hole drilling system

Growing community of inventors

Mississauga, Canada

James Jing Yao