DR. QUAN BAO NGUYEN, M.D
Osteopathic Medicine at Holly Hall St, Houston, TX

6782959, Aug 31, 2004

May 13, 2003

10/436709

James C. Minikus - Spring TX
Chris E. Cawthorne - The Woodlands TX
Stephen C. Steinke - The Woodlands TX
Gary R. Portwood - Kingwood TX
Gary E. Garcia - The Woodlands TX
David P. Moran - The Woodlands TX
Quan V. Nguyen - Houston TX

Smith International, Inc. - Houston TX

E21B 1008

1754201, 175430

A cutter element for a drill bit has a crest that defines a crest line. The crest can be non-rectilinear. The crest line of each cutter element defines an angle with respect to the axis of the rolling cone on which the cutter element is mounted. The cutter elements define different angles with respect to the cone axis and with respect to each other.

5131480, Jul 21, 1992

Jul 30, 1991

7/737640

Alan W. Lockstedt - Tomball TX
Quan V. Nguyen - Houston TX

Smith International, Inc. - Houston TX

E21B 1016, E21B 1050

175374

A milled tooth rotary cone rock bit, as it is operated in a borehole, subjects the heel of each cone into contact with the borehole wall when the gage row milled teeth wear. The heel row of each cone is relieved and tungsten carbide chisel inserts are equidistantly placed within the relieved heel row. The heel row inserts cooperate with the gage row milled teeth and progressively cut more of the gage of the borehole as the row of milled teeth on the gage of the cone wear. Moreover, the gage row milled teeth are partially hardfaced leaving relieved areas on the cutting side of each tooth to enhance the cutting action of the gage row of each cone.

6336512, Jan 8, 2002

Feb 1, 2000

09/495602

Michael A. Siracki - The Woodlands TX
Steven W. Peterson - The Woodlands TX
Chris E. Cawthorne - The Woodlands TX
Quan V. Nguyen - Houston TX

Smith International, Inc. - Houston TX

E21B 1008

175371, 175331, 384 94

A drill bit having a canted or non-canted leg backface, a canted or non-canted seal in the interface between the cone backface and the shirttail, and a canted seal that can be semi-encapsulated so that there is no straight-line path across the seal.

6192999, Feb 27, 2001

Oct 13, 1998

9/170412

Quan V. Nguyen - Houston TX

Smith International, Inc. - Houston TX

E21B 1018, E21B 1060

175340

A novel nozzle and retainer assembly are used in an earth boring rock bit. A tapered interface between the nozzle and retainer protects the nozzle from impact and breakage downhole. A bushing may also be used in conjunction with an alternative nozzle and retainer assembly.

5358061, Oct 25, 1994

Oct 21, 1993

8/141298

Quan Van Nguyen - Houston TX

Smith International, Inc. - Houston TX

E21B 1000

175371

Sealed bearing roller cone rock bits are prone to seal wear and failure due to the encroachment of abrasive drill cuttings into the seal gland. A hard metal cuttings diverter pad angularly positioned across the bit leg backface, adjacent the trailing edge of the leg shirttail edge, wipes the accumulated drill cuttings from the rotating cone backface. A circumferential groove, formed in the bit leg backface, promotes a relatively high volume flow of drilling fluid at the seal gland entrance to flush away the abrasive cutting particles not diverted by the hard metal diverter pad.