COMUNE CHINA DIMILANO TUTORIAL TO

US009970239B2

(12) Oesterberg
United States Patent (10) Patent No.: US 9 ,970,239 B2
(45) Date of Patent: *May 15, 2018
( 54 ) DRILL BITS INCLUDING RETRACTABLE (56 ) References Cited
PADS , CARTRIDGES INCLUDING
RETRACTABLE PADS FOR SUCH DRILL U . S . PATENT DOCUMENTS
BITS, AND RELATED METHODS
2,819 ,043 A * 1/1958 Henderson ............ E21B 10 /006
( 71) Applicant: Baker Hughes Incorporated , Houston , 175 /291
TX (US) 4 ,711,311 A 12 /1987 Underwood et al.
(Continued )
(72 ) Inventor: Marcus Oesterberg , Kingwood , TX FOREIGN PATENT DOCUMENTS
(US)
( 73 ) Assignee : Baker Hughes Incorporated , Houston , Wo 2006085105 A1 8 /2006
TX (US)
WO 2009002996 Al 12 /2008
(Continued )
( * ) Notice : Subject to any disclaimer, the term of this
patent is extended or adjusted under 35 OTHER PUBLICATIONS
U .S .C . 154 (b ) by 105 days. Trinkel, Bud . Fluid Power e Book 24 Chapter 6 — Fluid Power
This patent is subject to a terminal dis Circuits Explained , Apr. 25, 2008, 15 pages.
claimer. (Continued )
(21) Appl.No.: 14/750,066
Primary Examiner — Robert E Fuller
( 22 )
à Filed : Jun . 25 , 2015 Assistant Examiner — David Carroll
(65 ) Prior Publication Data (74 ) Attorney , Agent, or Firm — TraskBritt
US 2015/0292268 A1 Oct. 15, 2015 (57) ABSTRACT
Related U . S . Application Data
(63) Continuation of application No. 13/ 160 ,015 , filed on An earth -boring tool may comprise at least one cavity
Jun . 14 , 2011, now Pat. No. 9 ,080 , 399 . formed in a face thereof. At least one retractable pad residing
in the at least one cavity may be coupled to a piston located
(51) Int. CI. at least partially within the at least one cavity . Additionally ,
E2IB 10 /62 ( 2006 .01 ) a valve may be positioned within the earth -boring tool and
E21B 10 /42 ( 2006 .01) configured to regulate flow of an incompressible fluid in
(Continued ) contactwith the piston through an opening of a reservoir. A
cartridge may comprise a barrel wall defining a first bore ,
(52 ) U .S . CI. and a piston comprising at least one retractable pad posi
CPC .............. E21B 10 /42 ( 2013 .01); E21B 77064 tioned at least partially within the first bore . The barrel wall
( 2013 .01 ); E21B 10 / 322 (2013 .01); E21B and the piston may define a first reservoir within the first
10 /60 ( 2013 .01); E21B 10 /62 ( 2013 .01) ; E21B bore, and a valve may be positioned and configured to
7/04 (2013.01) regulate flow through an opening to the first reservoir.
(58 ) Field of Classification Search Related methods and devices are also disclosed .
CPC . E21B 7 /04 ; E21B 7 /064; E21B 10 /42 ; E21B
10 /62 ; E21B 10 /322
(Continued ) 18 Claims, 12 Drawing Sheets

130

132

156

110

136 136
128 - 128
 US 9,970 ,239 B2
Page 2

2
(51 ) Int. Cl. 2007/0199739 A1 * 8/ 2007 Schwefe ......... ..... E21B 10 / 573
175 /426
E21B 7 /06 (2006 .01)
E21B 10 /32 (2006 .01) 2009 /0008151 A11 /2009 Turner et al.
E21B 10 /60 ( 2006 . 01) 2010 /0012313 A1 * 1/ 2010 Longfield E21B 23/00
166 /66 .6
E21B 7 /04 (2006 .01 ) 2010 /0071956 A1 * 3/2010 Beuershausen . ....... E21B 10/62
(58) Field of Classification Search 2012/0318580 Al 12 /2012 Oesterberg
175 /61
USPC .......... ....... ...... 175 /61, 266 , 284
See application file for complete search history . FOREIGN PATENT DOCUMENTS
(56 ) References Cited WO 2009 101477 A2 8 /2009
wo 2010036834 A2 4 / 2010
U .S . PATENT DOCUMENTS WO 2010042797 A2 4 /2010
WO 2010042797 A4 4 /2010
5 , 553,678 A * 9 / 1996 Barr .. E21B 4 / 02
175 /324 OTHER PUBLICATIONS
5 ,813 , 480 A 9 / 1998 Zaleski et al.
6 ,089 ,332 A 7 / 2000 Barr et al. International Search Report for International Application No. PCT/
6, 230, 822 B1 5 / 2001 Sullivan et al. US2012 /042400 , dated Feb . 27 , 2013 , 3 pages.
6 , 419, 032 B1 7 / 2002 Sullivan et al. Written Opinion of the International Search Authority for Interna
6 , 540, 033 B1 4 / 2003 Sullivan et al. tional Application No. PCT/US2012 /042400 , dated Feb . 27, 2013 ,
6, 543,312 B2 4 / 2003 Sullivan et al. 6 pages .
6 , 571, 886 B1 6 / 2003 Sullivan et al. International Preliminary Report on Patentability , for International
6 , 626, 251 B1 9 / 2003 Sullivan et al. Application No . PCT/US2012/042400 , dated Dec . 17, 2013, 7
7 ,066 ,280 B2 6 / 2006 Sullivan et al. pages.
7 ,497,276 B2 3/ 2009 Pastusek et al. Suplementary European Search Report and Opinion for European
7 ,506,695 B2 3 /2009 Pastusek et al . Application No. 12801069, dated Mar. 3 , 2016 , 5 pages.
7, 510 ,026 B2 3/ 2009 Pastusek et al. First Chinese Office Action for Chinese Application No .
7 ,604 ,072 B2 10 / 2009 Pastusek et al. 2012800352419 dated Mar. 27, 2015, 13 pages.
7 , 849 ,934 B2 12/ 2010 Pastusek et al. Chinese First Search for Chinese Application No. 2012800352419
2002/0112887 A1 * 8 /2002 Harrison E21B 7 /04
175 / 27 dated Mar. 27 , 2015 , 1 page .
2006 /0272859 A1 * 12 / 2006 Pastusek .............. E21B 21 /08 Canadian Examination Report for Canadian Application No .
175 / 40 2838732 dated Feb . 3 , 2015, 4 pages .
2007/0102195 A1 5/ 2007 Denoix
2007 /0119630 Al 5/ 2007 Hall et al. * cited by examiner
U . S . Patent May 15 , 2018 Sheet 1 of 12 US 9 , 970 ,239 B2

To
Drawworks

Drawworks

30

TUTTE
EE wed TYTTTTTTTTT
FEUE 100

FIG . 1
U . S . Patent May 15, 2018 Sheet 2 of 12 US 9 , 970 ,239 B2

100 -

114
116

124 110

128

122

FIG . 2
U . S . Patent May 15, 2018 Sheet 3 of 12 US 9 , 970 ,239 B2

114

116
100
1

w
wie
www

Www

Wher

- --
-
128

128
" 118
122

FIG . 3
U . S . Patent May 15, 2018 Sheet 4 of 12 US 9 ,970 ,239 B2

132
162

156

110

136 - 136
136
128 -
FIG ..4A 128
em 128

132

162

156

110
136 - 136
128
FIG . 4B 128
128
U . S . Patent May 15 , 2018 Sheet 5 of 12 US 9 , 970 ,239 B2

140
156 152 162

154

146 142
148
- 150
160

128
144 -
144

FIG . 5A

140 152
- 156
150 162

154
146
148 -

144
IT160
_ 128
160

FIG . 5B
U . S . Patent May 15, 2018 Sheet 6 of 12 US 9 , 970 ,239 B2

194
187

188
??????????
... .. . . ...
WA 196

- 189

192
184 -
FIG . 6A

194 187
- 186
.. . . . .. . . . . ... .... ... .
196
- - - -
.
1
- - .

189
190

- 192
184 / FIG . 6B
U . S . Patent May 15, 2018 Sheet 7 of 12 US 9 , 970 ,239 B2

200
- 206206 202
202

204

210

_ 212

FIG . ZA

200
-206
206 202
202

L I L I L L IT
- - -

|
204

208

212
210 FIG . ZB
U . S . Patent May 15, 2018 Sheet 8 of 12 US 9 , 970 ,239 B2

314

)
60
(
312

310 III

300

FIG . 8
 sam - -
U . S . Patent May 15 , 2018 Sheet 9 of 12

312
US 9 ,970,239 B2

300 324
- 324

ww W
112 4320
320

Int322

FIG . 9

310

ogoooool 590

0000
, YHTITY
HITUTT
Bº00005 mo ool 00 DO ooooooooool
TUULUUUU

FIG . 10
U . S . Patent May 15, 2018 Sheet 10 of 12 US 9 , 970,239 B2

310

Temperature
Accelerometers Magnetometers sensors
346 348 350

Memory
344
Power Processor
sappy
340 I
supply
342 Communication
port
352

Optional 356
Initiation Optional sensor
analyzer sensors receiver
MWD
communication
system
50

Strain
Optional
sensor remote
sensors Remote
processing
system
354

FIG11
U . S . Patent May 15 , 2018 Sheet 11 of 12 US 9 ,970 ,239 B2

400
430

440

402

452

410 410

FIG . 12
U . S . Patent May 15 , 2018 Sheet 12 of 12 US 9 ,970 ,239 B2

500
544 522

534 534

540 - + + 542

520

530

532

510

FIG . 13
 US 9 ,970 ,239 B2
DRILL BITS INCLUDING RETRACTABLE In further embodiments , an earth -boring drill bit may
PADS, CARTRIDGES INCLUDING comprise a plurality of cavities in a face thereof, and a
RETRACTABLE PADS FOR SUCH DRILL retractable pad coupled to a first piston located at least
BITS , AND RELATED METHODS partially within each cavity of the plurality . The earth - boring
drill bit may additionally comprise a substantially incom
CROSS -REFERENCE TO RELATED pressible fluid in contact with the piston and contained
APPLICATION within a first reservoir, and a plurality of bores in fluid
communication with the plurality of cavities and in contact
This application is a continuation of U .S . patent applica with the substantially incompressible fluid . Furthermore , a
iled Jun
tion Ser. No. 13 /160,015 , filed Jun . 14
14 , 2011
2011 ., now
now US Pat . 10 second piston may be located at least partially within each
U .S . Pat
No. 9,080 ,399 , issued Jul. 14 , 2015 , the disclosure ofwhich bore of the plurality of bores ; and a swash plate may be
is hereby incorporated herein in its entirety by this reference. operably coupled to each second piston .
In yet additional embodiments , a method of operating an
TECHNICAL FIELD earth -boring toolmay comprise drilling a borehole with an
15 earth -boring toolwith at least one retractable pad protruding
Embodiments of the present disclosure generally relate to from a face of the earth -boring tool adjacent at least one
cutting structure . The method may further comprise opening
earth -boring tools including retractable pads. Embodiments a valve within the earth -boring tool to release a fluid from a
additionally relate to components for such earth -boring first reservoir positioned beneath the at least one retractable
tools , such as cartridges including retractable pads , and 20 pad and reducing the amount of protrusion of the at least one
related methods. retractable pad from the face of the earth -boring tool while
within the borehole, and resuming drilling after reducing the
BACKGROUND amount of protrusion of the at least one retractable pad from
the face of the earth -boring tool.
The trend in United States land and other unconventional 25 In yet further embodiments , a method of forming a curved
oil and gas exploration is tending toward a horizontal borehole may comprise extending at least one retractable
development of oil and gas wells , where a borehole is drilled pad positioned within a face of a drill bit at a first side of a
into , and then to laterally follow , a hydrocarbon -producing borehole while drilling, and retracting the at least one
formation . Such horizontal development of oil and gas wells retractable pad at a second side of the borehole while
typically requires directional drilling, wherein a vertical 30 drilling .
borehole segment is drilled , followed by a curved borehole
segment which , in turn , transitions to a horizontal or other BRIEF DESCRIPTION OF THE SEVERAL
borehole segment extending laterally to follow the forma VIEWS OF THE DRAWINGS
tion . Typically the curved borehole segment is drilled with
a bit having a relatively low aggressiveness , in order to 35 FIG . 1 shows a schematic view of a drilling rig including
provide stability and control of the tool face . In forming the a drill bit in accordance with an embodiment of the present
lateral , or horizontal, borehole segment the operator may disclosure .
want to optimize the rate -of-penetration (ROP ). To optimize FIG . 2 shows an isometric view of a drill bit including
the overall ROP using conventional bits, the operator may retractable pads according to an embodiment of the present
utilize a round trip , tripping out the bit with relatively low 40 disclosure .
aggressiveness and tripping in another bit with relatively FIG . 3 shows a bottom view of the drill bit shown in FIG .
high aggressiveness. Such a round trip may be time con
suming and costly due to the wasted rig time and necessity FIG . 4A shows a schematic view of a portion of the drill
for using two different drill bits. bit of FIG . 2 , showing fluid channels through a bit body of
In view of the foregoing, improved earth -boring tools , 45 the drill bit and showing the retractable pads in an extended
improved earth -boring tool components, and improved drill position .
ing methods, would be desirable . FIG . 4B shows a schematic view of the portion of the drill
bit shown in FIG . 4A , with the retractable pads in a retracted
position .
BRIEF SUMMARY
50 FIG . 5A shows a cartridge assembly including a retract
In some embodiments, an earth - boring tool may comprise able pad for use in a drill bit such as shown in FIG . 2 , the
at least one cavity formed in a face thereof. A retractable pad retractable pad shown in an extended position .
may be positioned in the at least one cavity adjacent the face FIG . 5B shows the cartridge assembly of FIG . 5A with the
and coupled to a piston located at least partially within the retractable pad shown in a retracted position .
at least one cavity . Additionally, a substantially incompress - 55 FIG . 6A shows a cartridge assembly including a retract
ible fluid may be in contact with the piston and contained able pad and a second piston for use in a drill bit such as
within a first reservoir , and a valve may be positioned within shown in FIG . 2 , the retractable pad shown in an extended
the earth -boring tool and configured to regulate flow through position .
an opening of the first reservoir. FIG . 6B shows the cartridge assembly of FIG . 6A with the
In additional embodiments, a cartridge for an earth -boring 60 retractable pad shown in a retracted position .
tool may comprise a barrel wall defining a first bore and a FIG . 7A shows a cartridge assembly including a retract
piston comprising at least one retractable pad positioned at able pad and a diaphragm for use in a drill bit such as shown
least partially within the first bore. Additionally , the car- in FIG . 2 , the retractable pad shown in an extended position .
tridge may comprise a first reservoir within the first bore FIG . 7B shows the cartridge assembly of FIG . 7A with the
adjacent the piston , an opening to the first reservoir, and a 65 retractable pad shown in a retracted position .
valve positioned and configured to regulate fluid flow FIG . 8 shows an exploded view of a shank and an
through the opening. electronics module of the drill bit of FIG . 2 .
 US 9 ,970 ,239 B2
FIG . 9 shows a cross -sectional view of the shank of FIG . generates electrical signals in response to pressure variations
of the drilling mud in the mud supply line 66 . The electrical
FIG . 10 shows a perspective view of the electronics signals are transmitted by a surface conductor 72 to a surface
module of FIG . 8. electronic processing system 80 , which is conventionally a
FIG . 11 shows a schematic diagram of the electronics 5 data processing system with a central processing unit for
module of FIG . 8 . executing program instructions, and for responding to user
FIG . 12 shows a partial cross -sectional view of a drill bit commands entered through either a keyboard or a graphical
including a swash plate according to an embodiment of the pointing device . The mud pulse telemetry system is provided
present disclosure . for communicating data to the surface concerning numerous
FIG . 13 shows a partial cross - sectional view of a drill bit 10 downhole conditions sensed by well logging and measure
including a valve according to an embodimentof the present ment systems that are conventionally located within the
disclosure . MWD communication system 50 .Mud pulses that define the
data propagated to the surface are produced by equipment
DETAILED DESCRIPTION conventionally located within the MWD communication
15 system 50 . Such equipment typically comprises a pressure
The illustrations presented herein are not meant to be pulse generator operating under control of electronics con
actual views of any particular device , or related method , but tained in an instrument housing to allow drilling mud to vent
are merely idealized representations which are employed to through an orifice extending through the drill collar wall .
describe embodiments of the present invention . Addition - Each time the pressure pulse generator causes such venting,
ally, elements common between figures may retain the same 20 a negative pressure pulse is transmitted to be received by the
numerical designation . mud pulse transducer 70 . An alternative conventional
Although some embodiments of the present disclosure are arrangement generates and transmits positive pressure
depicted as being used and employed in drag bits, persons of pulses. As is conventional, the circulating drilling mud also
ordinary skill in the art will understand that the embodi- may provide a source of energy for a turbine - driven gen
ments of the present disclosure may be employed in hybrid 25 erator subassembly (not shown ) which may be located near
drill bits or other drill bit configurations. Accordingly , the a bottom -hole assembly (BHA ). The turbine -driven genera
term “ earth -boring tool” and as used herein , means and tor may generate electrical power for the pressure pulse
includes any type of drill bit or other earth -boring apparatus generator and for various circuits including those circuits
for use in drilling or enlarging bore holes or wells in earth that form the operational components of the measurement
formations . 30 while - drilling tools . As an alternative or supplemental
FIG . 1 depicts an example of an apparatus for performing source of electrical power , batteries may be provided , par
subterranean drilling operations . A drilling rig 10 may ticularly as a backup for the turbine- driven generator.
include a derrick 12 , a derrick floor 14 , a drawworks 16 , a For directional drilling , the drillstring 30 may include a
hook 18 , a swivel 20 , a Kelly joint 22 , and a rotary table 24 . mud motor 90 and a bent sub and /or a steering sub 92 at a
A drillstring 30 , which may include a drill pipe section 32 35 location near the drill bit 100 . When drilling a straight
and a drill collar section 34 , extends downward from the borehole segment, the steering sub 92 and the drill bit 100
drilling rig 10 into a borehole 40 . The drill pipe section 32 may both be rotated relative to the borehole 40 . In view of
may include a number of tubular drill pipe members or this, the drill bit 100 may be rotated off -center and may drill
strands connected together and the drill collar section 34 a slightly oversized borehole 40 , due to the steering sub 92
may likewise include a plurality of drill collars . Optionally , 40 rotating and rubbing along the wall of the borehole 40 .
the drillstring 30 may include a measurement-while - drilling Optionally , a steering pad on the steering sub 92 may be
(MWD ) logging subassembly and cooperating mud pulse moved to a retracted position , which may allow the drill bit
telemetry data transmission subassembly , which are collec - 100 to be rotated on -center while drilling a straight borehole
tively referred to as an MWD communication system 50 , as segment .
well as other communication systems known to those of 45 When drilling a curved borehole segment, the mud motor
ordinary skill in the art. 90 may be utilized to rotate the drill bit 100 relative to the
During drilling operations, drilling fluid may be circulated borehole 40 , while the drillstring 30 located above the mud
from a mud pit 60 through a mud pump 62, through a motor 90 ,may not rotate relative to the borehole 40. In view
desurger 64, and through a mud supply line 66 into the of this, the drill bit 100 may be rotated on - center and the
swivel 20 . The drilling mud ( also referred to as drilling fluid ) 50 steering sub 92 may not rotate relative to the borehole 40 and
flows through the Kelly joint 22 and into an axial central may consistently apply a side force on one side of the
bore in the drillstring 30 . Eventually, it exits through nozzles borehole 40, which may cause the drill bit 100 to follow a
or other apertures, which are located in a drill bit 100 , which curved path through the formation. If the steering sub 92
is connected to the lowermost portion of the drillstring 30 . includes a movable steering pad , the steering pad may be
The drilling mud flows back up through an annular space 42 55 positioned in an extended position while forming the curved
between the outer surface of the drillstring 30 and the inner borehole segment.
surface of the borehole 40 , to be circulated to the surface However, in some embodiments, a bent sub and /or steer
where it is returned to the mud pit 60 through a mud return i ng sub 92 may not be included for directional drilling . In
line 68 . such embodiments, the formation of a curved borehole
A shaker screen (not shown ) may be used to separate 60 segment may be facilitated utilizing devices and methods
formation cuttings from the drilling mud before it returns to according to the present disclosure without utilizing a bent
the mud pit 60 . The optional MWD communication system sub and/ or steering sub 92 , such as discussed herein with
50 may utilize a mud pulse telemetry technique to commu- reference to FIGS. 12 and 13 .
nicate data from a downhole location to the surface while As shown in FIG . 2 , the drill bit 100 may comprise a bit
drilling operations take place . To receive data at the surface , 65 body 110 and a shank 112. The bit body 110 may include a
a mud pulse transducer 70 is provided in communication number of blades 114 and fluid channels 116 located
with the mud supply line 66 . The mud pulse transducer 70 between the blades 114 defining an outer surface of the bit
 US 9 ,970,239 B2
body 110 . The bit body 110 may additionally include a assembly 140 to the bit body 110 . For example , the flange
plurality of nozzles 118 ( FIG . 3 ), which may be located on 160 may be welded to the face of the drill bit 100 ( FIG . 2 ),
the bit body 110 to direct fluid through the fluid channels which may maintain the cartridge assembly 140 within the
116 . The blades 114 may include a plurality of cutting bit body 110 and also may provide a fluid -tight sealbetween
structures 122 (e . g ., polycrystalline diamond compact 5 the cartridge assembly 140 and the bit body 110 . Addition
(PDC ) cutters ), such as in a crown or face region of the drill ally , wiring 162 may be provided and routed through the bit
bit 100 and the blades 114 may include wear-inhibiting body 110 to provide electrical communication between the
structures 124 (e .g ., tungsten carbide wear buttons ), such as valve 156 and an electronics module 310 (described in
in a gage region of the drill bit 100 . further detail herein with reference to FIGS . 8 - 11 ).
As shown in FIGS. 2 and 3 , the bit body 110 of the drill 10 In another embodiment, shown in FIGS. 6A and 6B , a
bit 100 may include a plurality of retractable pads 128 cartridge assembly 180 may include a first barrel wall 182
located on the bit face . The bit face is shown in FIG . 3, and defining a first bore and a first piston 184 positioned within
is the leading region of the drill bit 100 that engages the the bore, a perimeter of the first piston 184 sealed against the
bottom of a borehole during drilling operations (i.e ., the first barrel wall 182 . Additionally , the cartridge assembly
portion of the bit that is opposite the shank 112 ). For 15 180 may include a second piston 186 , and a valve 187
example , each retractable pad 128 may be located on a blade positioned between the first and second pistons 184 and 186 ,
114 of the bit body 110 at a position rotationally trailing a respectively, and configured to regulate flow between a first
row of cutting structures 122 . In further embodiments, each reservoir 189 and a second reservoir 191.
retractable pad 128 may rotationally lead a row of cutting S imilar to the piston 144 of the cartridge assembly 140 ,
structures 122 . 20 depicted in FIGS. 5A and 5B , the first piston 184 of the
As shown in FIGS. 4A and 4B , the bit body 110 may cartridge assembly 180 may include a carrier 188 , such as a
additionally include fluid channels 130 within the bit body steel carrier, that may include a gland fitted with seals 190
110 , which may extend from a central fluid channel 132 to to prevent fluid from passing between the perimeter of the
the nozzles 118 and to cavities 136 in the bit body 110 first piston 184 and the first barrel wall 182 , and may also be
containing the retractable pads 128 . The central fluid chan - 25 fitted with a bearing or wear ring. The first piston 184 may
nel 132 may extend to the exterior of the drill bit 100 through also include a retractable pad 192, which may be coupled to
an opening in the shank 112 ( FIG . 8 ). or integrally formed with the carrier 188 .
In some embodiments , each adjustable pad 128 may be The second piston 186 may be positioned within a second
included in a cartridge assembly 140 , 180 , 200 , such as bore defined by a second barrel wall 194 , a perimeter of the
shown in FIGS. 5A , 5B , 6A , 6B , 7A , and 7B , which may be 30 second piston 186 sealed against the second barrelwall 194 .
positioned within the cavity 136 in the blade 114 of the bit The second piston 186 may also include a seal 196 , such as
body 110 . one ormore of an O -ring, a quad ring, a square ring, a wiper,
As shown in FIGS. 5A and 5B , a cartridge assembly 140 a backup ring, and other packing, which may provide a seal
may include a barrel wall 142 defining a bore, a piston 144 between the second piston 186 and the second barrel wall
positioned within the bore , a perimeter of the piston 144 35 194 .
sealed against the barrel wall 142 . The piston 144 may Although in the embodiment shown in FIGS. 6A and 6B
include a carrier 146 , such as a steel carrier, that may include shows the surfaces of the first and second pistons 184 and
a gland fitted with seals 148 to prevent fluid from passing 186 , respectively , exposed to the incompressible fluid and
between the sealed perimeter of the piston 144 and the barrel the drilling fluid having similar sizes , the surface areas of the
wall 142 , and may also be fitted with a bearing or wear ring . 40 opposing surfaces of the second piston 186 may be sized
The piston 144 also includes the retractable pad 128, which differently, such as to provide a pressure multiplier to
may be coupled to or integrally formed with the carrier 146 . increase the pressure of the incompressible fluid relative to
For example , the retractable pad 128 may be comprised of the pressure applied by the drilling fluid . Additionally , the
carbide , or other wear-resistantmaterial, and may be welded size and surface areas of the first piston 184 may be different
or brazed to the carrier 146 . Upon insertion into the bore , a 45 than the size and surface areas of the second piston 186 .
surface 150 of the piston 144 and the barrel wall 142 may In yet further embodiments , a cartridge assembly 200 may
define a fluid reservoir 152. The cartridge 140 may further include a flexible diaphragm 202 to provide an expandable
include an opening 154 to the fluid reservoir 152 and a valve fluid reservoir 204 , as shown in FIGS. 7A and 7B . For
156 ( such as a piezo - electric valve ) located and configured example , an elastomeric member may be positioned over an
to control the passage of fluid through the opening 154 to the 50 end of the cartridge assembly 200 and provide a fluid barrier,
fluid reservoir 152 . As the reservoir 152 is defined by the yet still allow for fluid pressure to be communicated from
barrel wall 142 and the surface 150 of the piston 144 , the the drilling fluid within the bit body 110 (FIG . 2 ) through a
reservoir 152 may vary in size, depending upon the position valve 206 to a first reservoir 208 behind a piston 210
of the piston 144 within the borehole . A substantially incom - including a retractable pad 212 .
pressible fluid may substantially fill the reservoir 152, con - 55 As shown schematically in FIGS . 4A and 4B , the fluid
tacting the surface 150 of the piston 144 . In view of this channels 130 in the bit body 110 may connect the central
upon closure of the opening 154 by the valve 156 , the fluid channel 132 of the drill bit 100 (FIG . 2 ) to the cavity
incompressible fluid may be contained within the reservoir 136 containing the retractable pad 128 . In view of this , the
152 and the piston 144 may be held in position via hydraulic fluid channels 130 may provide fluid communication
pressure . Non -limiting examples of substantially incom - 60 between the central fluid channel 132 of the drill bit 100 to
pressible fluids that may be utilized include mineral oil , a cartridge 140 , 180 , 200 , such as described with reference
vegetable oil, silicone oil , and water . to FIGS. 5A , 5B , 6A , 6B , 7A , and 7B , positioned within the
The cartridge assembly 140 may be sized for insertion cavity 136 . A valve may selectively allow fluid communi
into the cavity 136 of the bit body 110 (FIGS. 4A and 4B ), cation between the central fluid channel 132 and the retract
and may include a flange 160 thatmay be utilized to position 65 able pad 128 . For example , a valve such as valve 156 , 187 ,
the cartridge assembly 140 at a predetermined depth within 206 described with reference to the cartridges 140 , 180 , 200
the cavity 136 and may also be utilized to join the cartridge may be utilized to selectively allow fluid communication
 US 9,970 ,239 B2
between the central fluid channel 132 and the retractable pad in a manner suitable for at least partially attenuating accel
128 , 192 , 212 . The valve 156 , 187 , 206 may be electrically eration forces resulting from drilling operations by utilizing
actuated (e .g ., a piezo -electric valve ) and may be in elec - a material such as a visco -elastic adhesive .
trical communication with and operated by an electronics In addition to operating valves 156 , 187 , 206 to control
module 310 that may be located in the shank 112 of the drill 5 fluid communication between the central fluid channel 132
bit 100 such as described in U .S . patent application Ser. No. and the retractable pads 128 , 192, 212 , the electronics
12/ 367,433 , now U .S . Pat. No. 8, 100 ,196 , issued Jan . 24 , module 310 may be configured to perform a variety of data
2012 , and Ser. No. 12 /901, 172 , now U .S . Pat . No. 7, 987 , collection and /or data analysis functions.
925 , issued Aug . 2 , 2011 , and U . S . Pat . Nos. 7 ,497 , 276 ; In some embodiments , such as shown in FIG . 11, the
7 ,506 ,695; 7,510 ,026 ; 7 ,604 ,072 ; and 7, 849, 934 , each to 10 electronics module 310 may include a power supply 340
Pastusek et al., each titled “METHOD AND APPARATUS (e.g., a battery ), a processor 342 ( e.g., a microprocessor ),
FOR COLLECTING DRILL BIT PERFORMANCE and a memory device 344 ( e . g ., a random -access memory
DATA ,” and each assigned to the assignee of the present device (RAM ) and read - only memory device (ROM )). The
application, the disclosure of each of which is incorporated electronics module 310 may additionally include at least one
by reference herein in its entirety . 15 sensor 346 , 348 , 350 configured for measuring physical
As shown in FIG . 8 , the shank 112 includes a central bore parameters related to the drill bit , which may include drill bit
300 formed through the longitudinal axis Z of the shank 112 . condition , drilling operation conditions, and environmental
In conventional drill bits , a central bore is configured for conditions proximate to the drill bit. In one embodiment, the
allowing drilling mud to flow therethrough . In this embodi- sensors 346 , 348 , 350 may include an acceleration sensor
ment, at least a portion of the central bore 300 of the shank 20 346 , a magnetic field sensor 348 , and a temperature sensor
112 is given a diameter sufficient for accepting an electronics 350 .
module 310 , which may be configured as a substantially The acceleration sensor 346 may include three acceler
annular ring . Thus, the electronics module 310 may be ometers configured in an orthogonal arrangement (i.e ., each
placed within the central bore 300 , about the end -cap 312 , of the accelerometers may be arranged at a right angle
which extends through the inside diameter of the annular 25 relative to each of the other accelerometers ). Similarly , the
ring of the electronics module 310 to create a fluid tight magnetic field sensor 348 may include three magnetometers
annular chamber with the wall of central bore 300 and seal configured in an orthogonal arrangement (i.e., each of the
the electronics module 310 in place within the shank 112 . magnetometers may be arranged at a right angle relative to
The end -cap 312 includes a cap bore 314 formed there each of the other magnetometers ). Although orthogonal
through , such that drilling mud may flow through the 30 arrangements (e.g., Cartesian coordinate system ) utilizing
end - cap 312 , through the central bore 300 of the shank 112 three sensors are described herein , other numbers of sensors
to the other side of the shank 112 , and then into the central and arrangements may also be utilized .
fluid channel 132 of drill bit 100 . FIG . 9 shows a cross A communication port 352 may also be included in the
sectional view of the end - cap 312 disposed in the shank 112 electronics module 310 for communication to external
without the electronics module 310 , illustrating an annular 35 devices such as a MWD communication system 50 and a
chamber 320 formed between the end -cap 312 and the walls remote processing system 354. The communication port 352
of the central bore 300 of the shank 112 . A first sealing ring may be configured for a direct communication link 356 to
322 and a second sealing ring 324 form a protective, fluid the remote processing system 354 using a direct wire
tight, seal between the end - cap 312 and the wall of the connection or a wireless communication protocol, such as ,
central bore 300 to protect the electronics module 310 (FIG . 40 by way of example only , infrared , BLUETOOTH® , and
8 ) from adverse environmental conditions. The protective 802. 11a /b / g protocols. Using the direct communication link
seal formed by the first sealing ring 322 and the second 356 , the electronics module 310 may be configured to
sealing ring 324 may also be configured to maintain the communicate with a remote processing system 354 such as,
annular chamber 320 at approximately atmospheric pres for example , a computer, a portable computer, and a per
sure. 45 sonal digital assistant (PDA ) when the drill bit 100 is not
In some embodiments , the first sealing ring 322 and the downhole . Thus , the direct communication link 356 may be
second sealing ring 324 may be formed of material suitable used for a variety of functions, such as , for example , to
for a high -pressure , high - temperature environment, such as, download software and software upgrades , to enable setup
for example , a Hydrogenated Nitrile Butadiene Rubber of the electronics module 310 by downloading configuration
(HNBR ) O -ring in combination with a PEEK back - up ring. 50 data , and to upload sample data and analysis data . The
Additionally, the end- cap 312 may be secured to the shank communication port 352 may also be used to query the
112 by a number of connection mechanisms such as, for electronics module 310 for information related to the drill bit
example , a secure press - fit utilizing sealing rings 322 and 100, such as, for example , bit serial number, electronics
324 , a threaded connection , an epoxy connection, a shape module serial number, software version , total elapsed time
memory retainer, a weld , and a braze . 55 of bit operation , and other long term drill bit data , which
The electronics module 310, may be configured as a may be stored in the memory device 344 .
flex - circuit board , shown in a flat configuration in FIG . 10 . As the valves 156 , 187, 206 may be located within the bit
The flex -circuit board configuration may facilitate the bend body 110 of the drill bit 100 and the electronics module 310
ing and shaping of the electronics module 310 into a that operates the valves 156 , 187 , 206 may be located in the
generally annular ring -shape, as shown in FIG . 8 , suitable 60 shank 112 of the drill bit 100 , the control system for the
for disposition about the end - cap 312 and into the central retractable pads 128 , 192, 212 may be included completely
bore 300 . The flex - circuit board may include a high - strength within the drill bit 100 .
reinforced backbone (not shown ) to facilitate the reliable In some methods of operation of the drill bit 100, the
transmission of acceleration forces to sensors of the elec - retractable pads 128 , 192, 212 of the drill bit 100 may be
tronics module, such as accelerometers . Additionally, other 65 initially positioned in an extended position , such as a fully
areas of the flex -circuit board , which may bear non - sensor extended position , as shown in FIGS. 5A , 6A , and 7A . With
electronic components , may be attached to the end -cap 312 the retractable pads 128 , 192 , 212 positioned in an extended
 US 9 ,970 ,239 B2
10
position , a curved borehole segmentmay be formed with the bit 100 through the drill string 30 , and a force may be
drill bit 100 using directional drilling techniques , such as to applied to the retractable pads 128 , 192 , 212 by the under
transition from a vertical borehole segment to a horizontal lying formation . Upon opening of the valves 156 , 187 , 206 ,
orientation. In the extended position , the retractable pads the force applied to the retractable pads 128 , 192 , 212 by the
128 , 192, 212 may provide a depth -of-cut limiting feature 5 WOB on the undrilled formation ahead of the drill bit 100
that may provide a reduced aggressiveness of the drill bit may cause the substantially incompressible fluid within the
100 that may facilitate the drilling of the curved borehole by associated reservoir 152, 189 , 208 to flow out of the reser
limiting the effective exposure of cutting structures 122 voir 152, 189 , 208 through the valve 156 , 187, 206 and cause
adjacent the retractable pads 128 , 192, 212 . In one embodi- the retractable pads 128 , 192, 212 to be retracted into the bit
ment, the retractable pads are located substantially within a 10 body 110 , as shown in FIGS. 5B , 6B , and 7B . In embodi
cone region C of the drill bit (FIG . 3 ), adjacent a centerline ments that utilize an open cartridge assembly 140 , the
CL ( FIG . 3 ) of drill bit 100 . After the curved borehole incompressible fluid may flow out of the reservoir 152 and
segment is drilled within the formation , the retractable pads mix with the drilling fluid in the bit body 110 . In embodi
128 , 192 , 212 may then be retracted into the bit body 110 , ments that utilize a cartridge assembly 180 , 200 with a
increasing the depth -of -cut and the aggressiveness of the 15 second reservoir 191, 204 , the incompressible fluid may
drill bit 100 by increasing the effective exposure of cutting flow out of the first reservoir 189 , 208 and into the second
structures 122 adjacent the retractable pads 128 , 192 , 212 , reservoir 191, 204 , causing the volume of second reservoir
which increased aggressiveness may facilitate the efficient 191 , 204 to expand, as shown in FIGS. 6B and 7B .
formation of a substantially straight borehole segment, such In some embodiments, the retractable pads 128 , 192 , 212
as a horizontal borehole segment by increasing ROP for a 20 may be extended within the borehole after they have been
given rotationable speed of drill bit 100 . retracted . To extend the retractable pads 128, 192, 212
To retract the retractable pads 128 , 192 , 212 , a signal may within the borehole, another signal, such as a signal similar
be provided to the electronics module 310 . In some embodi- to , or the same as, the signal to retract the retractable pads
ments , an acceleration of the drill bit 100 may be utilized to 128 , 192 , 212 may be provided to the electronics module
provide a signal to the electronics module 310 . For example , 25 310 . Upon receiving the signal , an electrical current may be
the drill bit 100 may be rotated at various speeds ,which may provided to the valves 156 , 187, 206 corresponding to the
be detected by the accelerometers of the acceleration sensor retractable pads 128 , 192, 212 and the valves 156 , 187 , 206
346 . A predetermined rotational speed , or a predetermined may open , allowing fluid therethrough . The drill bit 100 may
series ( e .g ., a pattern ) of various rotational speeds within a be positioned off of the bottom of the borehole and drilling
given time period , may be utilized to signal the electronics 30 fluid may be pumped into the central fluid channel 132 of the
module 310 to retract the retractable pads 128 , 192 , 212 . To drill bit 100 . The fluid pressure within the central fluid
facilitate the reliable detection of accelerations correlating to channel 132 of the drill bit 100 may then cause fluid to flow
the predetermined rotational speed signal or signal pattern through the valves 156 , 187 , 206 and into the associated
by the electronics module 310 , the weight-on -bit (WOB ) reservoirs 152, 189, 208 , causing the volume of reservoirs
may be reduced , such as to substantially zero pounds ( zero 35 152 , 189 , 208 to expand and the retractable pads 128 , 192 ,
Kg ) WOB . 212 to extend from the bit face . After the retractable pads
In further embodiments , another force acting on the drill 128 , 192, 212 have been moved to the extended position ,
bit 100 may be utilized to provide a signal to the electronics such as shown in FIGS. 5A ,6A , and 7A , the valves 156 , 187 ,
module 310 . For example, the drill bit 100 may include a 206 may be closed to maintain the expanded volume of
strain gage in communication with the electronics module 40 reservoirs 152, 189 , 208 , holding retractable pads 128 , 192,
310 that may detect WOB . A predetermined WOB , or a 212 in the extended position , and drilling may commence .
predetermined series (e.g ., pattern ) ofWOB , may be utilized In embodiments that include a second reservoir 191, 204 ,
to signal the electronics module 310 to retract the retractable such as shown in FIGS. 6A , 6B , 7A , and 7B , pressure may
pads 128 , 192, 212 . To facilitate the reliable detection of be applied to the fluid in the second reservoir 191, 204 , such
WOB correlating to the predetermined WOB signal by the 45 as through the second piston 186 or through the flexible
electronics module 310 , the rotational speed of the drill bit diaphragm 202 , by the fluid within the central fluid channel
100 may be maintained at a consistent rotational speed (i.e ., 132 of the drill bit 100 and the fluid within the second
a consistent rotations per minute (RPM ) ). In some embodi- reservoir 191 , 204 may be flowed into the first reservoir 189 ,
ments, the rotational speed of the drill bit 100 may be 208 . In embodiments without a second reservoir 191, 204 ,
maintained at a speed of substantially zero RPM while 50 drilling fluid may direct the incompressible fluid into the
sensing the WOB signal. reservoir 152 ( FIG . 5A ). In further embodiments without a
After the electronics module 310 detects the signal to second reservoir 191 , 204 , drilling fluid may be utilized as
retract the retractable pads 128 , 192 , 212 ( e. g., accelerations the incompressible fluid . In such embodiments, wherein
correlating to the predetermined rotational speed signal or drilling fluid is used as the incompressible fluid , a screen or
strain measured by the strain gage correlating to the prede - 55 other filter medium (not shown ) may be utilized to inhibit
termined WOB signal), an electric current may be provided solid debris from passing through the valve 156 .
to the valves 156 , 187 , 206 corresponding to the retractable In additional embodiments, a drill bit 400, 500 including
pads 128 , 192 , 212 and the valves 156 , 187, 206 may open , retractable pads 410 , 510 may be configured to selectively
allowing fluid therethrough . For example , an electrical cir - retract and extend individual retractable pads 410 , 510 of the
cuit may be provided between the power supply 340 ( e . g ., 60 drill bit 400 , 500 , respectively, as shown in FIGS . 12 and 13 .
battery ) of the electronics module 310 and the valves 156 , In such embodiments , the extension and retraction of the
187, 206 , as the valves 156 , 187 , 206 may require relatively retractable pads 410 , 510 while drilling may be utilized for
little power to operate ( e. g., the valves 156, 187 , 206 may be the drilling of a curved borehole segment by varying the
piezo - electric valves thatmay be in a normally closed mode aggressiveness of cutting structures 122 ( FIG . 2 ) in different
and each utilizes about 5 watts of power to open ) . 65 locations on the bit face .
After sending the signal or signals to retract the retract - In some embodiments, a drill bit 400 may include a piston
able pads 128 , 192, 212 , weight may be applied to the drill 402 in fluid communication with each retractable pad 410
 US 9 ,970,239 B2
and each piston 402 may be coupled to a swash plate 420 , the fluid passage 532 to a retractable pad 510 , while block
as shown in FIG . 12 . The swash plate 420 may comprise an ing fluid communication between a corresponding fluid
upper plate 422 and a lower plate 424 , which rotate relative passage 534 between the central fluid passage 544 and the
to one another at an interface 426 . The upper plate 422 may exterior of the drill bit 500. A second circumferential region
not rotate relative to the borehole , and the lower plate 424 5 542 of the valve 520 may provide fluid communication
may rotate with the drill bit 400 . For example , the upper between a retractable pad 510 and an exterior portion of the
plate 422 may be attached to one or more rods 430 that drill bit 500 , while preventing fluid communication between
prevent the upper plate 422 from rotating relative to the the central fluid passage 544 and either of the fluid channels
borehole . A plurality of pistons 402 may be coupled to the 5 32 and 534 corresponding to the retractable pad 510 .
lower plate 424 by a hinged connection , such as a ball -and- 10 In operation , the central fluid passage 544 of the drill bit
socket connection 440 , and the lower plate 424 may rotate , 500 may be pressurized relative to a fluid surrounding the
along with the drill bit 400 and the pistons 402, relative to exterior of the drill bit 500. When the fluid channels 532 and
the upper plate 422. The pistons 402 may extend into bores 534 corresponding to a retractable pad 510 pass the first
450 in a bit body 452 and be in fluid communication with the circumferential region 540 of the valve 520 , the retractable
retractable pads 410 . 15 pad 510 may be pressurized . During the pressurizing process
In operation , the upper plate 422 and lower plate 424 may (e.g ., as the fluid channel 532 passes the first circumferential
be tilted relative to the primary longitudinal axis of the drill region 540 of the valve 520 ), the fluid channel 532 to the
bit 400 , such as by manipulating one or more of the rods 430 retractable pad 510 may be opened to the pressurized fluid
attached to the upper plate 422 , which may cause the pistons within the central fluid passage 544 of the drill bit 500 and
402 to reciprocate within the bores 450 in the bit body 452 20 the retractable pad 510 may become extended in response to
upon rotation of the drill bit 400 . The reciprocating pistons the fluid pressure . As the drill bit 500 rotates, the fluid
402 may then cause the retractable pads 410 to move inward channels 532 and 534 corresponding to the retractable pads
and outward relative to the bit face as the drill bit 400 rotates 510 pass the second circumferential region 542 of the valve
within the borehole , as a result of hydraulic pressure forces 520 and a fluid communication between the fluid channel
generated by the reciprocating pistons 402 acting on the 25 532 and the fluid channel 534 is provided through the valve
retractable pads 410 . The swash plate 420 may cause the 520, resulting in venting. During the venting process ( e. g .,
pistons 402 to move downward and cause the retractable as the fluid channel 532 passes the second circumferential
pads 410 to extend when the retractable pads 410 pass a first region 542 of the valve 520 ) , fluid communication is pro
side of the borehole and to move upward and cause the vided between a retractable pad 510 and the exterior of the
retractable pads 410 to retract as the retractable pads 410 30 drill bit 500, which may result in venting and a reduction in
pass a second side of the borehole . In view of this , the the pressure of the fluid in communication with the retract
depth -of- cut for the drill bit 400 may be greater on the able pad becoming reduced and the retractable pad 510
second side of the borehole than the first side and the drill retracting . The valve 520 may be oriented relative to a
bit 400 may remove more material from the second side of borehole to cause the retractable pads 510 to move inward
the borehole and directional drilling may be achieved . 35 at a location corresponding to a first side of the borehole and
Furthermore, the direction achieved ( e . g ., the degree of outward relative to a second side of the borehole as the drill
deviation from a straight path ) may be determined by the bit 500 rotates within the borehole . In view of this , the depth
angle that the swash plate 420 is oriented relative to the of cut for the drill bit 500 may be greater on the second side
primary longitudinal axis of the drill bit 400 . of the borehole than the first side and the drill bit 500 may
In further embodiments , such as shown in FIG . 13 , each 40 remove more material from the second side of the borehole
retractable pad 510 of a drill bit 500 may be in fluid and directional drilling may be achieved . Furthermore , the
communication with a valve 520 , such as a valve similar to direction achieved ( e . g ., the degree of deviation from a
the valve described with reference to U .S . Pat. No. 5 ,553, straight path ) may be determined by the position of the valve
678 to Barr et al., titled “ MODULATED BIAS UNITS FOR 520 relative to the borehole and the fluid pressure supplied
STEERABLE ROTARY DRILLING SYSTEMS,” the dis - 45 to the central fluid passage 544 of the drill bit 500 .
closure of which is incorporated by reference herein in its While the present invention has been described herein
entirety . The valve 520 may be coupled to a rod 522 thatmay with respect to certain embodiments , those of ordinary skill
prevent the valve 522 from rotating relative to the borehole in the art will recognize and appreciate that it is not so
during drilling operations. A bit body 530 may include fluid limited . Rather , many additions, deletions and modifications
channels 532 therein to provide fluid communication 50 to the embodiments described herein may be made without
between the valve 520 and the retractable pads 510 . Addi- departing from the scope of the invention as hereinafter
tionally , the bit body 530 may include fluid channels 534 claimed . In addition , features from one embodimentmay be
thatprovide fluid communication between the valve 520 and combined with features of another embodiment while still
an exterior of the drill bit 500 . As shown in FIG . 13 , the fluid being encompassed within the scope of the invention as
channels 534 may provide fluid communication to the 55 contemplated by the inventor.
exterior of the drill bit 500 at a location at or near the gage What is claimed is:
region of the drill bit 500 . In further embodiments , the fluid 1 . A drill bit for drilling a subterranean formation, com
channels 534 may be directed downward through the bit prising :
body 530 and provide fluid communication to the exterior of a body;
the drill bit 500 through the nozzles 118 , located in the face 60 a cartridge located within a recess in a face portion of a
region of the drill bit 500 . The fluid channels 532 , 534 blade extending from thebody, the cartridge including:
formed through the bit body 530 will rotate with the drill bit a barrel wall defining at least one cavity opening to the
500 during drilling operations, thus will rotate relative to the face portion of the blade ;
valve 520 . The valve 520 may be configured with at least a retractable pad positioned in the at least one cavity
two different circumferential regions 540, 542 . A first cir- 65 opening to the face portion of the blade and coupled
cumferential region 540 may provide fluid communication to a piston located at least partially within the at least
between a central fluid passage 544 in the bit body 530 and one cavity ;
 US 9,970 ,239 B2
13 14
a substantially incompressible fluid in contact with the 13. The drill bit of claim 1 , wherein the retractable pad is
piston and contained within at least one reservoir ; located substantially within a cone region adjacent a cen
and terline of the drill bit.
a valve positioned within the at least one cavity defined 14 . A method of forming a curved borehole , the method
by the barrel wall and configured to regulate a 5
volume of the substantially incompressible fluid con comprising:
tained within the at least one reservoir . extending at least one retractable pad proximate a first
2 . The drill bit of claim 1 , further comprising an elec side of a borehole while drilling, the at least one
tronics module in electrical communication with the valve , retractable pad coupled to at least one piston , and the at
the electronics module comprising at least one sensor 10 least one retractable pad positioned at least partially
located within the drill bit . within at least one cavity defined by a barrel wall of a
3 . The drill bit of claim 2 , wherein the at least one sensor cartridge located within a recess in a face portion of a
comprises at least one of an accelerometer or a strain gage . blade extending from the body of the drill bit ;
4 . The drill bit of claim 2 , wherein the electronics module retracting the at least one retractable pad proximate a
is configured to open and close the valve to adjust an 15 second side of the borehole while drilling; and
extension of the retractable pad in response to a sensed controlling the extending and retracting of the at least one
change in at least one of rotational speed or weight on the retractable pad responsive to sensed drilling conditions
drill bit. with at least one valve positioned within the at least one
5 . The drill bit of claim 2 , wherein the electronics module cavity defined by the barrel wallby regulating a volume
further comprises a power source configured to activate the 20 of a substantially incompressible fluid contained within
valve . at least one reservoir, the volume of the substantially
6 . The drill bit of claim 2 , further comprising a shank incompressible fluid in contact with the at least one
coupled to the body, wherein the electronics module is piston .
located in the shank.
7 . The drill bit of claim 1 . wherein the cartridge further 25 15 . The method of claim 14 , wherein controlling the
comprises another piston separated from the piston by a extending and retracting of the at least one retractable pad
volume of another substantially incompressible fluid . comprises utilizing an electronics module for setting an
8 . The drill bit of claim 7, wherein the cartridge further initial position of the at least one retractable pad responsive
comprises another reservoir containing the volume of the to at least one of an acceleration signal correlated to a
another substantially incompressible fluid in contact with the 30 predetermined rotational speed or a strain signal correlated
another piston , wherein the valve is positioned and config to a predetermined weight on the drill bit.
ured to regulate at least one of the volume of the substan - 16 . The method of claim 14 , wherein extending and
tially incompressible fluid in the at least one reservoir or the retracting the at least one retractable pad comprises varying
volume of the another substantially incompressible fluid in aggressiveness of cutting structures in different locations on
the another reservoir. 35 the body of the drill bit by selectively extending and
9 . The drill bit of claim 1, wherein the cartridge is secured retracting individual retractable pads located on the body of
to the drill bit by a weld proximate the face portion of the the drill bit.
blade . 17 . The method of claim 14 , further comprising utilizing
10 . The drill bit of claim 1, wherein the valve is positioned a swash plate including a stationary upper plate and a
and configured to open and close communication between 40 rotatable lower plate for extending and retracting the at least
the at least one reservoir and a drilling fluid channel within one retractable
one retractable nad relative toto the
pad relative the body
body of
of the
the drill
drill bit
bit ..
the drill bit.
11. The drill bit of claim 1 , wherein the valve comprises ing18at. The method of claim 17, further comprising position
least one reciprocating piston between the rotatable
a piezoelectric valve .
ses 45
12 . The drill bit of claim 1, wherein the piston comprises lower plate of the swash plate and the at least one retractable
45 pad
low
a steel carrier coupled to the retractable pad , wherein the for directing the at least one retractable pad to extend
retractable pad comprises carbide and the steel carrier com proximate the first side of the borehole and to retract
prises a seal gland sealing the steel carrier to an interior wall proximate the second side of the borehole .
of the at least one cavity . * * * * *