U.S. patent application number 14/691604 was filed with the patent office on 2016-10-27 for wellbore drill bit having shear cutters and gouging cutters.
The applicant listed for this patent is Shear Bits, Ltd.. Invention is credited to Timothy P. Beaton, John James Herman, Ryan J. C. Marley.
Application Number | 20160312538 14/691604 |
Document ID | / |
Family ID | 55802287 |
Filed Date | 2016-10-27 |
United States Patent
Application |
20160312538 |
Kind Code |
A1 |
Marley; Ryan J. C. ; et
al. |
October 27, 2016 |
WELLBORE DRILL BIT HAVING SHEAR CUTTERS AND GOUGING CUTTERS
Abstract
A fixed cutter drill bit includes a bit body and at least one
primary blade formed in the bit body and defining a surface profile
on the bit body. The at least one primary blade extends from a
first selected radial distance from a center or rotation of the bit
body to a gage portion. At least one shear cutter affixed to the at
least one blade. At least one gouging cutter affixed to the bit
body rotationally ahead of the at least one blade. At least one
nozzle is disposed in the bit body in a rotational position between
the at least one primary blade and the at least one gouging
cutter.
Inventors: |
Marley; Ryan J. C.;
(Airdrie, CA) ; Herman; John James; (Cypress
County, CA) ; Beaton; Timothy P.; (Calgary,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Shear Bits, Ltd. |
Calgary |
|
CA |
|
|
Family ID: |
55802287 |
Appl. No.: |
14/691604 |
Filed: |
April 21, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 10/12 20130101;
E21B 10/54 20130101; E21B 10/43 20130101 |
International
Class: |
E21B 10/12 20060101
E21B010/12 |
Claims
1. A fixed cutter drill bit, comprising: a bit body; at least one
primary blade formed in the bit body and defining a surface profile
on the bit body, the at least one primary blade extending from a
first selected radial distance from a center or rotation of the bit
body to a gage portion; at least one shear cutter affixed to the at
least one blade; at least one gouging cutter affixed to the bit
body rotationally displaced from the at least one blade; and at
least one fluid orifice disposed in the bit body in a rotational
position between the at least one primary blade and the at least
one gouging cutter.
2. The fixed cutter drill bit of claim 1 further comprising at
least one secondary blade formed in the bit body and
circumferentially spaced apart from, the at least one secondary
blade extending from a second selected distance from the center or
rotation and extending radially to a gage portion, the second
distance greater than the first distance.
3. The fixed cutter drill bit of claim 2 further comprising at
least one shear cutter on the at least one secondary blade.
4. The fixed cutter drill bit of claim 2 wherein the at least one
secondary blade defines a surface profile located at a selected
distance less extensive along a longitudinal dimension of the bit
body than a corresponding surface profile defined by the at least
one gouging cutter.
5. The fixed cutter drill bit of claim 2 wherein the at least one
secondary blade comprises at least one shear cutter thereon, the at
least one shear cutter on the at least one secondary blade defining
a surface profile located at a selected distance lower along a
longitudinal dimension of the bit body than a corresponding surface
profile defined by the at least one gouging cutter.
6. The fixed cutter drill bit of claim 1 wherein the at least one
shear cutter on the at least one primary blade defines a surface
profile located at a selected distance lower along a longitudinal
dimension of the bit body than a corresponding surface profile
defined by the at least one gouging cutter.
7. The fixed cutter drill bit of claim 1 wherein the at least one
shear cutter comprises a polycrystalline diamond compact
cutter.
8. The fixed cutter drill bit of claim 1 wherein the at least one
gouging cutter comprises a tungsten carbide insert.
9. The fixed cutter drill bit of claim 1 wherein the at least one
shear cutter is disposed at a radial distance from a center of
rotation of the bit body less than a gage diameter defined by the
bit body.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
THE NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT
[0003] Not Applicable
BACKGROUND
[0004] This disclosure relates generally to the field of wellbore
drill bits used for drilling subsurface earthen formations. More
particularly, the disclosure relates to fixed cutter wellbore drill
bits having shear type cutting elements ("cutters") and pick or
gouging type cutters.
[0005] Fixed cutter bits known in the art include polycrystalline
diamond compact ("PDC") bits, wherein a plurality of PDC cutters
are affixed to a bit body in a selected arrangement on one or more
blades formed in the bit body.
[0006] Gouging type cutters are used in drill bits for drilling
mine shafts or tunnels, among other uses. Such bits are known in
the art as "claw" bits, one example of which is sold under the
trademark QUI-KLAW, which is a trademark of Drillhead, Inc. Such
bits are known to be useful in drilling clay, unconsolidated sand,
loose rock and gravel.
[0007] U.S. Pat. No. 8,505,634 issued to Lyons et al. describes a
drill bit having gouging cutters disposed adjacent to shear cutters
on a blade on the bit body. The shear cutters have a planar cutting
face, while the gouging cutting elements have a non-planar cutting
face, e.g., dome shaped or cone shaped.
[0008] Another type of fixed cutter drill bit that has both shear
cutters and gouging cutters is sold under the trademark PEXUS,
which is a trademark of Shear, Bits, Ltd., 407 2nd St. S.W., Suite
300, Calgary AB T2P 2Y3, Canada. It has been observed that such
drill bits may exhibit premature wear on the shear cutters disposed
on radially outward (from the center of rotation of the bit)
portions of blades (the "profile"). Such wear is believed to be a
result of being shielded from high velocity drilling fluid flow by
the gouging elements, such that such shear cutter overheat and wear
more quickly than expected. In applications where a drill bit
designer would select low cost shear cutters on conventional PDC
bits, such gouging and shear cutter bits need cutters made from
more heat resistant and therefore more expensive cutters to avoid
premature cutter wear due to thermal degradation (i.e., overheating
of the cutters).
[0009] It has also been observed that the foregoing drill bits
using shear and gouging type cutters may generally drill through
subsurface formations at slower rates lower than conventions fixed
cutter (e.g., PDC) drill bits. It is believed that such slower
drilling rates are related to the hydraulic energy of the drilling
fluid pumped through the drill bit courses or nozzles in the bit
body being directed less at the PDC cutters than at the gouging
elements. Such slower drilling rates may also be due to addition of
gouging elements to a full shear cutter drill bit cutting structure
may add excessive cutter surface area in contact with the earthen
formations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a top view of one example embodiment of a drill
bit according to the present disclosure.
[0011] FIG. 2 is a side view of the example embodiment of FIG.
1.
[0012] FIG. 3 shows a top view of another example embodiment of a
drill bit.
[0013] FIG. 4 shows an oblique view of the example embodiment of
FIG. 3.
[0014] FIG. 5 shows a coplanar view of a surface profile defined by
gouging cutters and shear cutters.
DETAILED DESCRIPTION
[0015] An example embodiment of a wellbore drill bit according to
the present disclosure is shown in top view (viewed from the
cutting end) in FIG. 1. The drill bit 10 may include a bit body 12
having features (FIG. 2) for connection to a drill string or
drilling tools for drilling a wellbore in subsurface formations.
The bit body 12 may be formed from steel and have an abrasion
resistant coating such as tungsten carbide applied to certain wear
susceptible areas (not shown) on the bit body 12. The bit body 12
may also be made, for example, from carbide matrix of compositions
known in the art.
[0016] The present example embodiment may include one or more
circumferentially, primary blade(s) 14. The one or more primary
blade(s) 14 may extend radially from a first selected radial
distance (D in FIG. 2) from a center or rotation C of the bit body
12 to a gage portion 14A located substantially at the radius of the
bit body 12. If more than one primary blade 14 is used, such
primary blades 14 may be azimuthally, circumferentially or
angularly spaced apart. The first selected distance D may be the
same for each primary blade 14 or may be different. Any one or more
of the primary blade(s) 14 may include at least one, and may
include a plurality of shear cutters 20. The shear cutters 20 may
be PDC cutters of any type known in the art. The shear cutters 20
may also be made from any other material known in the art to be
used for shear cutters on a fixed cutter drill bit. The shear
cutters 20 may be affixed to the bit body 12 at a rake angle
selected for the expected subsurface formations to be drilled by
the drill bit.
[0017] The present example embodiment may include one or more
secondary blades 15. The one or more secondary blades 15 may extend
from a second, respective radial distance (D2 in FIG. 3) from the
center of rotation C of the bit body 12 and may extend radially
outward to a gage portion 15A substantially at the gage radius of
the bit body 12. The one or more secondary blade(s) 15 may include
one or more shear cutters 20. The one or more shear cutters 20 on
the secondary blade(s) may be the same composition and structure as
the shear cutters 20 on the one or more primary blades 14, or may
be a different structure or composition. The one or more shear
cutters 20 on the one or more secondary blade(s) 15 may also be
made from any material known in the art to be used for shear
cutters on a wellbore drill bit.
[0018] Any or all of the one or more shear cutters 20 may be
affixed to a pocket or similar mounting feature formed into the one
or more primary blades 14 (and the secondary blade(s) 15 if shear
cutters are used thereon) using any attachment method or device
known in the art. Such methods or devices may include, but are not
limited to brazing.
[0019] In the present example embodiment, at least one or a
plurality of gouging cutters 16 may be affixed to the bit body 12
rotationally, circumferentially or azimuthally displaced from the
primary blade(s) 14 by a selected azimuthal angle along a direction
of rotation 11 of the bit body 12, the direction of rotation 11
being that which bit is rotated in a wellbore to drill through
subsurface formations. In the present example embodiment, the one
or more gouging cutters 16 may be rotationally ahead of a
corresponding primary blade 12, that is, rotationally displaced in
the direction of rotation to be rotationally forward of a cutting
surface (20A in FIG. 3) of the one or more shear cutters 16. The
gouging cutters 16 may be any type of gouging cutter known in the
art, for example, the structure of the QUI-KLAW brand gouging
cutters described in the Background section herein. In some
embodiments, the gouging cutters 16 may comprise ballistic shaped
tungsten carbide inserts. The gouging cutters 16 may be affixed to
the bit body 12 using any attachment means or device known in the
art for attaching gouging cutters to a bit body, including, without
limitation, brazing, welding or using a locking ring.
[0020] The terms "azimuthally" and "circumferentially" and
"rotationally" may mean angularly displaced referenced to the
direction of rotation 11. "Rotationally ahead of" may mean
angularly advanced along the direction of rotation 11.
"Rotationally behind" may mean angularly in back of with reference
to the direction of rotation 11. In order to avoid ambiguity, with
reference to the shear cutters 20, "ahead of" the shear cutters 20
rotationally, azimuthally or circumferentially means ahead in the
direction of rotation 11 with respect to a cutting surface of the
shear cutters.
[0021] In the present example embodiment, the gouging cutters 16
may be affixed to the bit body 12 in any suitable geometric
arrangement for gouging cutters used in a fixed cutter drill bit
having at least one shear cutter. For purposes of describing a
drill bit according to the present disclosure, a first group 16A of
shear cutters may be disposed rotationally displaced from, e.g.,
rotationally ahead of one of the primary blades 14, this particular
primary blade being shown at 24 in FIG. 1. One or more drilling
fluid orifices or jets 18 may be disposed azimuthally,
circumferentially or rotationally between the first group 16A of
gouging cutters 16 and the one 24 of the primary blades. The fluid
orifices or jets 18 may be oriented such that drilling fluid pumped
through the drill bit 10 during drilling is oriented toward the one
or more shear cutters 20 on the one 24 primary blade.
[0022] The example embodiment shown in FIG. 1 includes one or more
shear cutters 20 on the at least one secondary blade(s) 15. Other
embodiments of a drill bit may include at least one shear cutter
only on the one or more primary blade(s) 14. Such embodiments will
be explained in more detail with reference to FIGS. 3 and 4.
[0023] A side view of the example embodiment shown in FIG. 1 is
shown in FIG. 2. The bit body 12 may include features, such as
threads 12B to couple the bit body 12 to a drill string (not shown)
or a drilling tool (not shown). The bit body 12 may also include
features such as flats 12A for applying torque to the bit body 12
to engage the threads 12B with the drill string (not shown) and
apply a selected torque to the bit body 12 to ensure suitable
engagement of the threads 12B. The at least one primary blade 14 is
shown extending from the first selected distance D from the center
or rotation C to the gage portion 14A substantially at the radius
of the drill bit. The gage portion 14A may include one or more gage
inserts 22 therein. The gage inserts 22 may be made from any hard,
wear resistant material known to be used for gage inserts,
including without limitation, polycrystalline diamond, tungsten
carbide and cubic boron nitride.
[0024] In some embodiments, the one or more primary blade(s) 14 and
the one or more secondary blades 15 may be shaped to include a
tapered face 14C below (in the viewing direction of FIG. 2) the
gage portion 14A. The tapered face 14C may include one or more
shear cutters 20 of the same or different construction as the shear
cutters located elsewhere on the drill bit. The one or more primary
blades 14 is shown each extending from its respective first
selected distance D from the center of rotation C. The respective
first selected distance D may be as small as the smallest distance
known in the art to be used for shear cutters disposed on a fixed
cutter drill bit. The second selected distance will be explained
with reference to FIG. 3.
[0025] In embodiments that have one or more shear cutters 20 on the
one or more secondary blades 15, such shear cutters 20 may define a
profile surface that is, at corresponding radial distances from the
center or rotation C, located a selected distance H lower (in the
plane of view of FIG. 2) along the longitudinal dimension L of the
drill bit than a corresponding surface profile defined by the
gouging cutters 16.
[0026] FIG. 3 shows a top view of another example embodiment of a
drill bit 10A according to the present disclosure. The example
embodiment of FIG. 3 may be substantially the same as the
embodiment shown in FIG. 1, the exception being that the one or
more secondary blades 15 may exclude shear cutters. In embodiments
such as the one shown in FIG. 3, the one or more secondary blades
15 may define a surface profile that is at corresponding radial
distances from the center or rotation C located a selected distance
H lower (in the plane of view of FIG. 4) along the longitudinal
dimension L of the drill bit than a corresponding surface profile
defined by the one or more gouging cutters 16. FIG. 3 more clearly
shows the second selected distance D2 from which the one or more
secondary blades 15 begins with reference to the center of rotation
C. The selected radial distance D2 may be larger than the first
selected distance (D in FIG. 2). The selected radial distance D2
may be different for each secondary blade 15. Both the one or more
secondary blades 15 and the one or more primary blades 14 may
extend from the respective selected distances D2, D to a gage
radius defined by a respective gage portion 15A, 14A. Nozzles or
jets may be disposed at similar positions as in the embodiment
explained with reference to FIG. 1, that is, generally rotationally
between the gouging cutters 16 and a rotationally behind the
selected one of the one or more primary blades 14.
[0027] FIG. 5 shows a planar view of the surface profile P2 defined
by shear cutters 20 on one of the primary blades (14 in FIG. 2).
The view in FIG. 5 is such that all the shear cutters 20 are
rotated to the same plane. A side view of some of the gouging
cutters 16 rotated to the same plane as the view of the shear
cutters 20 is also shown in FIG. 5. The gouging cutters 16 define a
different surface profile P1. Thus the view in FIG. 5 represents
the axial position (position along the longitudinal dimension L) of
each cutter 16, 20 with respect to its radial position referenced
to the center of rotation (C in FIG. 3). As may be observed in FIG.
5, the gouging cutter profile surface P1 is advanced in the
longitudinal direction L by a distance H beyond the shear cutter
surface profile P2. In some embodiments, the gouging cutters 16 may
be positioned on the bit body (12 in FIG. 2) such that they do not
extend to the gage radius defined by the gage portions (14A, 15A in
FIG. 2.
[0028] A side view of the example embodiment shown in FIG. 3 is
shown in FIG. 4. The present example embodiment may also include
features on the bit body (e.g., threads and flats) to couple the
drill bit to a drill string or drilling tool.
[0029] In example embodiments such as shown in FIGS. 3 and 4, the
one or more primary blade(s) 14 may include one or more shear
cutters 20 as shown in the figures. Although both embodiments shown
and described herein, i.e., with reference to FIGS. 1 and 2, and
FIGS. 3 and 4, respectively, have six blades (3 primary, 3
secondary) equiangularly spaced apart from each other, different
embodiments may use more or fewer blades, generally but not
exclusively in a range of two to twelve total blades. Such other
embodiments may have the same or different circumferential,
azimuthal or angular spacing between adjacent blades. Gouging
cutters may be affixed to the bit body on a part thereof separate
from any blade structure, e.g., as shown in FIGS. 1 and 3.
[0030] A drill bit according to the present disclosure having one
or more gouging cutters on a drill bit having shear cutters may
include one or more of the following:
[0031] (i) protects the shear cutters from impact damage;
[0032] (ii) create large fractures in the formations which are more
efficient for drilling than shearing in some types of
formations;
[0033] (iii) drills formations with a smoother torque response than
a comparable drill bit having shear cutters alone; and
[0034] (iv) enables the bit drill to successfully drill through
formations that conventional fixed cutter (shear cutter only) drill
bits cannot drill.
[0035] While the invention has been described with respect to a
limited number of embodiments, those skilled in the art, having
benefit of this disclosure, will appreciate that other embodiments
can be devised which do not depart from the scope of the invention
as disclosed herein. Accordingly, the scope of the invention should
be limited only by the attached claims.
* * * * *