STEERABLE ROTARY DRILL BIT ASSEMBLY WITH PILOT BIT

A rotary drill bit assembly (1) suitable for directionally drilling a subsurface borehole the assembly (1) comprising a bit body (3) extending alo ng a central longitudinal bit-body axis (8), and having a bit-body face (10) at its front end, wherein an annular portion of the bit-body face is provide...

Full description

Saved in:
Bibliographic Details
Main Authors SMITH, DAVID GEORGE LIVESEY, RUNIA, DOUWE JOHANNES, WORRALL, ROBERT NICHOLAS
Format Patent
LanguageEnglish
French
Published 30.01.2003
Edition7
Subjects
EARTH DRILLING
EARTH DRILLING, e.g. DEEP DRILLING
FIXED CONSTRUCTIONS
MINING
OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS
Online AccessGet full text

Cover

More Information
Summary:A rotary drill bit assembly (1) suitable for directionally drilling a subsurface borehole the assembly (1) comprising a bit body (3) extending alo ng a central longitudinal bit-body axis (8), and having a bit-body face (10) at its front end, wherein an annular portion of the bit-body face is provided with chip-making elements (12); a pilot bit (20) extending along a central longitudinal pilot-bit axis (32), the pilot bit (20) being partly arranged within the bit body (3) and projecting out of the central portion (14) of th e bit-body face (10), a joint means (30) arranged to pivotably connect the pil ot bit (20) to the bit body (3) so that the bit-body axis (8) and the pilot-bit axis (32) can form a variable diversion angle; and a steering means (40, 42, 45, 47, 55, 62) arranged to pivot the pilot bit (20) in order to steer.</SDO AB>
Bibliography:Application Number: CA20022453353