Note: Descriptions are shown in the official language in which they were submitted.
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RESONANCE-ENABLED DRILLS, RESONANCE GAUGES, AND
RELATED METHODS
[0001] This application claims the benefit of priority of United States
Provisional Patent
Application Serial No. 63/159,435 filed March 10, 2021, the disclosure of
which is incorporated
by reference in its entirety for all purposes.
[0002] The present disclosure generally relates to machines that use resonance
to transfer energy
from the machine to a drill bit or bottom hole assembly to penetrate the
earth, concrete, or any
material to drill a hole or take a sample.
[0003] Generally, sonic drills have used counterrotating eccentrics
mechanically timed to
generate vertical forces while canceling the horizontal forces. The eccentrics
are typically driven
directly from an internal combustion engine or by an internal combustion
engine driving
hydraulics, which have response times longer than the penetration systems
response time
constant. A throttle controls these systems by engine speed or a valve or
driven pump speed.
[0004] Hydraulic controls have a slow response time, making the drill hard to
control by hand.
As the frequency increases and the drill approaches resonance, the system
requires less input
power, which causes the eccentrics rotation speed to increase. As a result,
the system is pulled
into the resonant condition. The operator nor the hydraulic system can respond
fast enough to
avoid speeding up into the resonant peak and remaining on the resonant peak.
[0005] What is needed is a resonance-enabled drill with quick response times
and finer control
so that the drill can stay at the recommended resonance frequency or desired
operating condition
SUMMARY
[0006] The present disclosure provides a resonance-enabled drill, comprising a
housing; one or
more force generators chosen from one or more voice coil actuators, one or
more eccentrics
driven by one or more electric motors, or combinations thereof; one or more
sonic heads coupled
to the one or more force generators; a plurality of springs coupling the
housing to the one or
more sonic heads, and a drill rod disposed on its proximal end to the one or
more sonic heads.
[0007] In certain embodiments, the drill further comprises a bit disposed on
the distal end of the
drill rod.
100081 In certain embodiments, the one or more voice coil actuators comprise a
coil assembly
rigidly disposed on the housing or on a reflection mass, and a magnet assembly
disposed on the
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one or more sonic heads. In certain embodiments, the coil assembly of each of
the one or more
voice coil actuators has little to no motion compared to the one or more sonic
heads.
100091 In certain embodiments, each eccentric is driven by one electric motor.
In certain
embodiments, the one or more force generators comprise two paired sets of
eccentrics configured
to exert no vertical force, using a 180 phase angle between the two paired
sets of eccentrics. In
certain embodiments, the one or more force generators comprise two paired sets
of eccentrics
configured to exert full vertical force, using a 00 phase angle between the
two paired sets of
eccentrics.
100101 In certain embodiments, the drill further comprises a seal disposed
between the housing
and the drill rod.
100111 In certain embodiments, the drill further comprises a spring-damper
disposed between the
drill rod and the bit. In certain embodiments, the spring-damper cushions
impact of the drill bit
by widening and lowering the impulse magnitude, whereby transfer of primary
resonant energy
to unwanted resonant modes is lowered, and the drill bit is kept in motion and
not fused with a
workpiece.
100121 In certain embodiments, the drill further comprises an energy transfer
rod and flange
adaptor disposed between the one or more sonic heads and the drill rod.
100131 In certain embodiments, the drill further comprises a rotor, stator,
and stator housing
disposed between the one or more sonic heads and the drill rod. The rotor is
disposed on the drill
string and the stator and stator housing each disposed on the housing, thus
allowing the sonic
drill rod to rotate. In certain embodiments, this configuration induces
torsional resonances when
the input force is oscillated on the rotary motor. in these embodiments,
between the one or more
sonic heads and the adapter, when present, a rotor provide rotation torques
onto the pipe A
decoupler/stator can also be between the rotation of the pipe and the one or
more sonic heads,
which are stationary. In one configuration, the rotor, stator, and stator
housing are tied together so
that the drill rod does not rotate but can oscillate from the input torque at
the rotor.
100141 In certain embodiments, the kinetic energy stored in the drill by the
one or more sonic
heads is directly offset by potential energy stored within the plurality
springs. In certain
embodiments, the drill further comprises a reflection mass coupled to the one
or more sonic
heads through a second plurality of springs and configured to offset the
kinetic energy stored in
the drill.
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[0015] In certain embodiments, the housing comprises a plurality of plates and
a plurality of
standoffs. In certain embodiments, during operation, the drill has a resonance
frequency and,
when on resonance, an alternating input force is in phase with the oscillation
velocity of the one
or more sonic heads. In certain embodiments, the oscillating input force is
provided from the
spinning eccentrics or voice coil force. In these embodiments, the force is
not constant but rather
oscillates (or alternates) up and down.
[0016] The present disclosure also provides a gauge for a sonic drill
configured to display
information to an operator when the drill is on or near resonance. The sonic
drill may be any
resonance-enabled drill disclosed herein. In certain embodiments, the
information comprises one
or more parameters chosen from an amplitude of the drill bit, a resonant
frequency of the drill, a
stress state, power components of the drill, and safe operating frequencies.
[0017] In certain embodiments, the gauge indicates one or more positions
chosen from bit
decoupling, a lower recommended range, a recommended operating condition, a
high
recommend range, and fusion. In certain embodiments, the power components of
the drill
comprise useful power, power delivered at the bit, power absorbed along the
drill string's length,
energy stored in the drill, and wasted power.
[0018] In certain embodiments, the gauge is further configured to display to
the operator where
mechanical resonance is located compared to operating conditions of the drill.
[0019] In certain embodiments, the gauge is further configured to show the
ratio of bit motion to
motion of the one or more sonic heads.
[0020] In certain embodiments, when penetration of the drill slows or ceases,
the gauge is
configured to display potential problems with options to remedy the lower-than-
desired
penetration rate.
[0021] Any resonance-enabled drill disclosed herein may comprise any gauge
disclosed herein.
[0022] The present disclosure further provides a method for selecting a
resonance frequency in a
sonic drill comprising a force generator, one or more sonic heads, and a
gauge. The phase is
measured between a force generator and one or more sonic heads in the sonic
drill. A resonance
frequency is selected based on the phase displayed on a gauge to indicate the
relative position of
the phase for resonance of the sonic drill. In certain embodiments, phase
between the force
generator and the one or more sonic heads in the sonic drill is measured and
resonance on the
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gauge is displayed to indicates where the resonance frequency is relative to
the current operating
frequency of the drill based on the phase measurement.
[0023] In certain embodiments, when the sonic drill comprises a bit, the
method further
comprises maximizing the ratio between the bit motion and the motion of the
one or more sonic
heads. In certain embodiments, when the sonic drill comprises a bit and
penetration of the bit is
slowed or ceased, the method further comprises reducing the weight on the bit
to adjust the
resonance frequency of the drill to continue drilling.
[0024] In certain embodiments, the method further comprises estimating the
stress state of the
drill. In certain embodiments, the sonic drill selects the resonance frequency
when an operating
condition changes. In certain embodiments, the operating condition is chosen
from pipe length,
the ratio between the drill bit motion and the motion of the one or more sonic
heads, weight on
the bit, or the workpiece.
[0025] In certain embodiments, weight applied to the bit is greater when
drilling a workpiece
with a lower soil stiffness than when drilling a workpiece with a greater soil
stiffness. In certain
embodiments, critical weight on the bit is pushed up to allow motion at the
drill bit to perform
drilling. In certain embodiments, as soil stiffness increases, less weight on
bit is required for
fusing. In certain embodiments, weight on the bit is inversely proportional to
soil stiffness.
[0026] In certain embodiments, the weight applied to the bit is great enough
to provide fusing
with the soil. The bit boundary condition changes from free to fused with the
soil. The soil
stiffness and viscous damping are now a part of the sonic drill system. The
drill system turns into
a sensor to measure the soil stiffness and viscous damping at the drill bit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The disclosure will be readily understood by the following detailed
description in
conjunction with the accompanying drawings, wherein like reference numerals
designate like
structural elements. The drawings provide exemplary embodiments or aspects of
the disclosure
and do not limit the disclosure's scope.
[0028] FIG. 1 shows a resonance-enabled drill comprising a voice coil and a
sonic head.
[0029] FIG. 2 shows a top perspective cross-section of a voice coil in a
resonance-enabled drill.
[0030] FIG. 3 shows a side plan view cross-section of the resonance-enabled
drill of FIG. 2.
[0031] FIG. 4 shows a side plan view of the resonance-enabled drill of FIG. 2.
100321 FIG. 5 shows a top plan view of the resonance-enabled drill of FIG. 2.
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100331 FIG. 6 shows a resonance-enabled drill with two voice coil actuators
coupled on the same
side of a sonic head.
100341 FIG. 7 shows a resonance-enabled corer with a core barrel assembly to
take soil samples.
100351 FIG. 8 shows a resonance-enabled corer with a core barrel assembly and
two sonic heads.
100361 FIG. 9 shows a resonance-enabled corer with a core barrel assembly to
take soil samples
with a configuration to cancel forces to the housing with opposing voice coils
to cancel resultant
forces to the housing.
100371 FIG. 10 shows the percent force with phasing two eccentric pairs from
in-phase (00) to
out of phase (1800).
100381 FIG. 11 shows the phasor vector relation of the resultant force
generated between two
sinusoidal forcing functions from one force phased relative to the other.
100391 FIG. 12 shows a meter that displays the current state of the drill
compared to the closest
system resonance.
100401 FIG. 13 shows the mode shape of (C) the displacement, (D) acceleration,
and (E) stress
of the drill system for (A) different lengths and (B) input frequencies. This
example displays a
single frequency and system length configuration, but the system's length and
frequency may be
adjusted.
100411 FIG. 14 shows the (B) displacement and (C) acceleration amplitudes of
the head and bit
versus the input frequency. The plots may be swept through various lengths of
pipe (A).
100421 FIG. 15 shows a table of the resonant frequencies (in Hertz) of the
penetration system
relative to the number of added sections of drill pipe.
100431 FIG. 16 shows (B) the plot of input power, useful power, wasted power,
and power is
delivered to the bit over the operating frequencies of the penetration system.
(A) The length of
pipes can also be selected. (C) Acceleration of the head and bit is also
plotted on the lower axis
and Input Power vs. Input Frequency.
100441 FIG. 17 shows a plot indicating where resonance is located, stable
operating conditions,
and unstable operation conditions for a hydraulically driven eccentric
penetration system.
100451 FIG. 18 shows the safe operating frequencies in white, where the
operations conditions
are shaded where the system stress state is too great, and failures will
likely occur.
100461 FIG. 19 shows an eccentric-driven sonic drill, where the eccentrics are
counterrotating
and timed together.
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[0047] FIG. 20 shows a dual electric motor drive for a dual eccentric sonic
drill. Each motor
drives a single spinning eccentric.
[0048] FIG. 21 shows four electric motor drives for a four eccentric sonic
drill organized as two
paired sets of eccentrics.
[0049] FIG. 22 shows the potential energy and kinetic energy changes of a
resonant system of
FIG. 21 as a function of time.
[0050] FIG. 23 shows the energy when the resonant system of FIG. 21 operates
at a frequency
below mechanical resonance.
[0051] FIG. 24 shows a single electric motor drive for a dual eccentric sonic
drill, where the
eccentrics are mechanically timed to each other. A rotor and stator drive the
rotational or
torsional vibration of the pipe, allowing the pile to not rotate but to
oscillate instead.
[0052] FIG. 25 shows (B) a plot of displacement amplitude and (C) acceleration
of the head and
bit versus frequency. (A) The length of pipes can also be selected.
[0053] FIG. 26 shows a meter that displays the current state of the drill bit
compared to
decoupled and fusion.
100541 FIG. 27 shows a resonance-enabled machine configured as a drill with a
voice coil-driven
system at the sonic head.
[0055] FIG. 28 displays a critical weight on bit gauge.
[0056] FIG. 29 displays that when the sonic drill was operated at nominally
constant frequency
of 120 Hz between 245 seconds and 250 seconds, the weight on bit affected the
system
performance.
[0057] FIG. 30 shows that a higher penetration rate was observed when the
weight on bit was
below the critical weight on bit.
[0058] FIG. 31 shows the tangents of the penetrations rates from FIG. 30.
[0059] FIG. 32 displays the relative push-and-pull forces from the hydraulic
cylinder of the sonic
drill that lift and push down the sonic drill.
[0060] FIG. 33 shows the resonance meter gauge readings during testing with a
GeoProbe 8150
LS using 40 ft of 4" drill pipe and a coring bit.
[0061] FIG. 34 is a schematic showing the top and bottom boundary conditions
operating on the
drill string of a drill rig with a sonic driver.
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100621 FIG. 35 shows the phase between input force and the measured head
acceleration of a
sonic drill as a function of frequency. The phases at 104.5 Hz are marked for
(A) no coupling at
the bit, (B) full coupling with sand, (C) full coupling with stiff clay, and
(D) full coupling with
granite.
100631 Table 1 lists reference numerals used throughout the figures and this
disclosure.
420 housing-to-second
sonic head
Table 1: Reference numerals
spring
100 drill
430 first-to-second
sonic head spring
105 energy absorbed within the system
440 housing-to-
reflection mass springs
115 peak-to-peak energy absorbed
500 voice coil actuator
within the system amplitude
510 first coil assembly
150 corer
515 first magnet
assembly
200 sonic heads
520 second coil
assembly
205 kinetic energy
525 second magnet
assembly
210 first sonic head
530 first eccentric
215 motion of first sonic head
540 second eccentric
220 second sonic head
530,540 first plurality of eccentrics
225 motion of second sonic head
550 third eccentric
230 (internal force) reflection mass
560 fourth eccentric
300 housing
550,560 second plurality of eccentrics
310 first housing plate
600 pile/drill rod
/drill string
312 housing ledge
610 seal
320 second housing plate
620 spring-damper
330 housing shell
630 bit
350 standoff
640 energy transfer rod
351 fastener
650 flange adaptor
400 springs
660 core barrel
405 potential energy
670 corer bit
410 housing-to-first sonic head spring
680 stator
683 stator housing
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685 rotor 710 core
700 the workpiece (concrete, strata,
etc.)
800 motors 840 fourth motor
810 first motor 845 fourth coupling
815 first coupling k1 first spring
constant
820 second motor k2 second spring
constant
825 second coupling li3 third spring
constant
830 third motor kx reflection mass
spring constant
835 third coupling
DETAILED DESCRIPTION
Resonance-Enabled Drill
[0064] A "resonance-enabled drill" is a type of resonance-enabled machine,
such as a sonic drill
or sonic penetration device, within this disclosure. Generally, within this
disclosure, "drill,"
"sonic drill," and "resonance-enabled drill" are used interchangeably. In
certain embodiments,
the drill is configured to function as a corer and can also be referred to as
a "resonance-enabled
corer."
[0065] Resonance is defined as when an oscillation system over a single
oscillation cycle the
stored energy of the drill matches the kinetic energy stored in the drill and
that results in the
force being in phase with the resultant velocity. By the definition of
resonance, a person of skill
in the art would readily understand how the drill operates. For example, when
the system is on
resonance, an alternating input force is in phase with the system oscillation
velocity of the one or
more sonic heads.
100661 To slow a hydraulically driven eccentric system, finer controls may be
used for the flow
driving the eccentrics. In certain embodiments, an energy-absorbing device,
such as a brake or
generator, may limit the speed. The system can reduce the input power to keep
the input
frequency below resonance. Disclosed herein is another method wherein an
electric motor drives
the counterrotating eccentrics. In certain embodiments, the motor is closed-
loop controlled to
control the speed. In certain embodiments, a motor brakes the system's speed
so that the
eccentrics can spin at any desired rate.
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[0067] The resonance-enabled drills disclosed herein comprise a force
generator, such as one or
more voice coil actuators or one or more pairs of eccentrics.
Voice coil actuators
[0068] A voice coil actuator commonly drives mechanical systems with linear
motion. The coil
assembly is disposed on the sonic head because it is lighter than the magnet
assembly and losses
from the inertia of the oscillating mass prevent the heavier mass from being
the sonic head.
Examples include loudspeakers to generate sound/music. Care has been taken to
reduce the coil
assembly's weight mounted to the speaker to provide the best performance with
the highest
efficiency.
[0069] With the coil moving, power wires delivering current to the coil are
always being
fatigued, limiting the life for the voice coil and the power wires delivering
current to the coil. As
disclosed herein, the voice coil is mounted to housing to mitigate fatigue and
increase reliability.
Still, up to now, this configuration caused reduced performance and lower
efficiency. By
configuring the voice coil assembly in a resonance-enabled drill, the kinetic
energy stored in the
drill by the voice coil assemblies' moving masses is directly offset by
potential energy stored
within the drill's springs Therefore, heavier voice coil assemblies can be
mounted on a sonic
head of the resonance-enabled drill without losing performance or efficiency.
[0070] The one or more sonic heads are configured to operate on a resonant
mode shape. The
one or more sonic heads are out of phase of one another. Each of the one or
more sonic heads is
coupled to the housing through a plurality of springs. When more than one
sonic head is present,
the sonic heads are also coupled with each other through a second plurality of
springs. The drill
is configured so that the forces transferred to the housing through the
coupling springs between
the one or more sonic heads and the housing are at or near zero over the
drill's operating range
around its resonant frequency.
[0071] In resonance-enabled drills driven by a voice coil, the range of
frequencies can and will
vary. A person of skill in the art understands to select a frequency range
suitable for operating the
resonance-enabled drill under the conditions needed for the selected
workpiece. For example, the
voice coil may operate between 60 Hz and 2,000 Hz (2 kHz), such as between 60
Hz and 100
Hz, between 100 Hz and 200 Hz, between 200 Hz and 300 Hz, between 300 Hz and
400 Hz,
between 400 Hz and 500 Hz, between 500 Hz and 600 Hz, between 600 Hz and 700
Hz, between
700 Hz and 800 Hz, between 800 Hz and 900 Hz, between 100 Hz and 1 kHz,
between 1 kHz
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and 1.1 kHz, between 1.1 kHz and 1.2 kHz, between 1.2 kHz and 1.3 kHz, between
1.3 kHz and
1.4 kHz, between 1.4 kHz and 1.5 kHz, between 1.58kHz and 1.6 kHz, between 1.6
kHz and 1.7
kHz, between 1.7 kHz and 1.8 kHz, between 1.8 kHz and 1.9 kHz, or between 1.9
kHz and 2
kHz. In certain embodiments, the frequency is greater than 60 Hz. In certain
embodiments, the
frequency is less than 2 kHz. In certain embodiments, the frequency is between
60 Hz and 250
Hz, such as between 60 Hz and 150 Hz.
[0072] FIG. 1 shows a resonance-enabled drill 100, comprising a housing 300, a
sonic head 210
coupled to the housing 300 by a first plurality of springs 410, a coil
assembly 510 disposed on
the housing 300, a voice coil magnet assembly 515 coupled to the sonic head
210, a drill rod 600
disposed on the proximal end to the sonic head 210 and on the distal end to a
bit 630. A seal 610
is disposed between the drill rod 600 and the housing 300. The voice coil
actuator 500 comprises
a coil assembly 510 and a magnet assembly 515. In this embodiment of the
single sonic head
resonance-enabled drill 100, the voice coil magnet assembly 515 is disposed
beneath and
coupled to the sonic head 210. During operation, the bit 630 contacts the
workpiece 700, which
can be soil, strata, rock formation, concrete, or other natural or manmade
feature, to form a
borehole.
[0073] Optionally, the resonance-enabled drill 100 further comprised a spring-
damper 620
disposed between the drill rod 600 and the bit 630. The spring-damper 620
widens or flattens the
impulse load from the drill bit 630. For example, if a resonance-enabled drill
100 made of only
steel impacts a rock formation 700, the formation has infinite impedance and
reflects the impact
fully onto the drill rod 600. The impact creates an impulse load and excites
all resonant
frequencies of the resonant system. With repeated blows, the energy quickly
transitions from the
primary resonant mode to a broadband of resonant frequencies, fusing the drill
bit 630 with the
formation 700.
[0074] By disposing a spring-damper 620 (with or without internal damping)
between the drill
bit 630 and the drill rod 600, the bit 630 can move with the end of the drill
rod 600 during
normal operation. When a hard substrate is encountered and impulse loads are
generated, the
spring-damper 620 cushions the impact by widening and lowering the impulse
magnitude. This
lowers the transfer of the primary resonant energy to unwanted resonant modes,
keeping the drill
bit 630 in motion and not fused with the strata 700. The bit's 630
susceptibility to fusing is
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lessened, the useful range of weight on bit 630 is widened, and the
acceleration force and energy
onto the bit 630 are lessened during drilling, causing less wear and extending
the service life.
[0075] In certain embodiments, the spring-damper 620 comprises a resilient
member, such as a
spring or a viscoelastic medium. The damping within the spring-damper 620 is
rate-dependent.
When present, the spring gives. The load through the transient impact
transfers by the damping
or viscous part of the viscoelastic medium.
[0076] Referring to FIGS. 2-5, the housing 300 comprises a first housing plate
310 and a second
housing plate 320. The sonic head 210 is coupled to the first housing plate
310 by a plurality of
housing-to-sonic head springs 410. The sonic head 210 is coupled to the second
housing plate
320 by a second plurality of housing-to-sonic head springs 410.
[0077] In certain embodiments, the resonance-enabled drill further comprises
an energy transfer
rod 640 and flange adaptor 650 disposed between the sonic head 210 and the
drill rod 600. In
this configuration, the seal 610 is disposed between the energy transfer rod
640 and the housing
300.
100781 Standoffs provide strength and rigidity to the machine. Separate
resonant modes do not
occur within the machine's structure. For instance, each sonic head 200 is
assumed to be a rigid
body, and the standoffs 350 ensure that each mass acts as a rigid body during
machine operation.
The number of standoffs in the plurality can be selected to accommodate the
size of the machine,
such as between 1 and, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25,
30, 35, 40, 45, 50, 75,
or 100. A large machine typically contains more standoffs than a smaller
machine for strength
and rigidity. Each standoff 350 is matched with springs 410 and fasteners 351,
so as the number
of standoffs 350 increases, so do the number of springs 410 and fasteners 351.
[0079] FIG. 6 shows a resonance-enabled drill 100 with two voice coil
actuators 500 coupled on
the same side of a sonic head 210. Each voice coil comprises a coil assembly
and a magnet
assembly. A first coil assembly 510 and second coil assembly 520 are disposed
on the housing
300. A first magnet assembly 515 and second magnet assembly 525 are coupled to
the sonic head
210.
[0080] FIG. 7 shows a resonance-enabled drill 150 with a core barrel 660 and a
corer bit 670 to
take soil samples. The core barrel 660 is disposed on the proximal end to the
sonic head 210. The
corer bit 670 is disposed on the distal end of the core barrel 660.
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[0081] FIG. 8 shows a resonance-enabled corer 150 with a core barrel 660, a
corer bit 670, and
two sonic heads 210,220. The first sonic head 210 is rigidly coupled to a
first magnet assembly
515, a plurality of housing-to-first moving mass springs 410, a plurality of
housing to second
moving mass springs 420, and a plurality of first moving mass to second moving
mass springs
430. The first sonic head 210 is further coupled to a housing ledge 312 by a
plurality of housing-
to-first sonic head springs 410 and to a second sonic head 220 by a plurality
of first-to-second
sonic head springs 430. The second sonic head 220 is coupled to the housing
300 via a plurality
of housing-to-second sonic head springs 420 and the first sonic head 210 by a
plurality of first-
to-second sonic head springs 430. In certain embodiments, the first coil
assembly 510 is rigidly
coupled to the housing 300 and has little to no motion compared to the sonic
heads 210,220
[0082] FIG. 9 shows a resonance-enabled corer 150 with a core barrel 660 and
corer bit 670 with
a configuration to cancel forces to the housing 300 with opposing voice coils
500 to cancel
resultant forces to the housing 300. In this embodiment, the first sonic head
210 is rigidly
coupled to a first magnet assembly 515, a plurality of housing-to-first moving
mass springs 410,
a plurality of housing to second moving mass springs 420, a plurality of first
moving mass to
second moving mass springs 430. The first sonic head 210 is further coupled to
a housing ledge
312 by a plurality of housing-to-first sonic head springs 410 and to a second
sonic head 220 by a
plurality of first-to-second sonic head springs 430. A first voice coil
assembly 510 is disposed the
top surface of the housing 300 inside the drill 150. The first voice coil
assembly MO is coupled
to the first magnetic assembly 515.
[0083] The second sonic head 220 is coupled to the housing 300 via a plurality
of housing-to-
second sonic head springs 420 and the first sonic head 210 by a plurality of
first-to-second sonic
head springs 430. The second voice coil assembly 520 is disposed on the bottom
surface of the
housing 300 inside the drill 150, pointing in the opposite direction of the
first voice coil 510. The
second voice coil assembly 520 is coupled to the second magnetic assembly 525.
If the housing
springs 410,420 are not completely offset, they can be adjusted to cancel the
resultant forces to
the housing 300.
[0084] FIG. 10 shows the percent force with phasing two eccentric pairs from
in-phase (00) to
out of phase (180 ). The vector math for the resultant force of the pair of
eccentrics is provided.
The vector math represents the image in FIG 11, which shows the phasor vector
relation of the
resultant force generated between two sinusoidal forcing functions from one
force phased
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relative to the other. FIG. 12 shows a meter that displays the current state
of the drill compared to
the closest system resonance.
100851 FIG. 13 shows the mode shape of (C) the displacement, (D) acceleration,
and (E) stress
of the drill system for (A) different lengths and (B) input frequencies. This
example displays a
single frequency and system length configuration, but its length and frequency
may be adjusted.
In certain embodiments, these plots represent angular displacement, angular
acceleration, and
angular stress for a corer rod undergoing torsional forces from the one or
more sonic heads.
100861 FIG. 14 shows the (B) displacement and (C) acceleration amplitudes of
the head and bit
versus the input frequency. The plots (A) may be swept through various lengths
of pipe.
100871 FIG. 15 shows a table of the undamped resonant frequencies of the
penetration system
relative to the number of added sections of drill pipe.
100881 FIG. 16 shows (B) the plot of input power, useful power, wasted power,
and power is
delivered to the bit over the operating frequencies of the penetration system.
(A) The length of
pipes can also be selected. (C) Acceleration of the head and bit is also
plotted on the lower axis
and Input Power vs. Input Frequency.
100891 FIG. 17 shows a plot indicating where resonance is located, stable
operating conditions,
and unstable operation conditions. With a hydraulic system driving spinning
eccentrics, an
unstable condition is encountered below resonance.
100901 FIG. 18 shows the safe operating frequencies in white, where the
operations conditions
are shaded where the system stress state is too great, and failures will
likely occur. The failures
are caused by overstressing the system at various locations, which may cause
instant failure, or
the system may be fatigued prematurely.
Eccentrics
100911 In certain embodiments, the force generator comprises one or more
eccentrics. In certain
embodiments, a motor drives each eccentric. In such embodiments, the motors
are electrically
synchronized. When a primary signal is generated, both motors are controlled
by the primary
signal. These motors counterrotate in relation to each other. Electric motors
have not been used
previously because the control system for electrically controlling motors to
sync to one another
has just recently been achieved. The industry has not understood that the
current operating
conditions are not recommended and could be improved using electric motors.
One favorable
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operating condition is identified. It is often found below resonance, where
the ratio of drill head
motion amplitude over drill bit motion amplitude is minimal.
100921 The drill bit generally moves more than the sonic head, permitting a
higher transfer of
power to the drill bit to drill. The drill may be unstable at this location
and need less energy than
at lower frequencies. The drill eccentrics rotational speed may increase, and
the system is pulled
through the favorable operating point. Therefore, with current technology,
sonic drills may not be
able to operate in such conditions.
100931 In certain embodiments, the resonance-enabled drill comprises double
eccentrics, such as
four in total, with phase control. FIG. 36 shows an eccentric-driven sonic
drill 100, where the
eccentrics 530,540 are counterrotating and timed together. The resonance-
enabled drill 100
comprised a housing 300, a sonic head 210 disposed within the housing 300, a
plurality of
eccentrics 530,540 disposed within the sonic head 210 and coupled to a motor
810 through a
coupling 815, a drill rod 600 is coupled to the sonic head 210 at the proximal
end. A drill bit 630
is coupled to the distal end of the drill rod 600. This drill 100 can be
configured as a corer 150
for a single rod length for sampling.
100941 FIG. 37 shows a dual electric motor drive 810,820 for a dual eccentric
sonic drill 100.
Each motor drives a single spinning eccentric. That is, motor 810 drives
eccentric 530 through
coupling 815, and motor 820 drives eccentric 540 through coupling 825. The
eccentrics 530,540
in this embodiment are counterrotating and electrically synchronized.
100951 FIG. 38 shows four electric motors 810,820,830,840 driving four
eccentrics
530,540,550,560 in a sonic drill 100. The eccentrics 530,540,550,560 are
organized into two
paired sets of eccentrics, 530,540 and 550,560. Each motor drives a single
spinning eccentric.
That is, motor 810 drives eccentric 530 through coupling 815, motor 820 drives
eccentric 540
through coupling 825, motor 830 drives eccentric 550 through coupling 835, and
motor 840
drives eccentric 560 through coupling 845.
100961 FIG. 39 shows the potential energy and kinetic energy changes of a
resonant system of
FIG. 21 as a function of time. The total amount of energy in the system is
constant and no energy
is absorbed within the system. FIG. 40 shows the energy when the resonant
system of FIG. 21
operates at a frequency below mechanical resonance. At this state, the
potential energy amplitude
is greater than the kinetic energy amplitude and the system uses additional
energy to balance the
system. This additional energy is absorbed within the system during operation.
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100971 FIG. 41 shows a cross section view of a single electric motor 810 drive
for a dual
eccentric 530,540 sonic drill 100, comprising a rotor 685 between the sonic
head 210 and the
drill rod 600 and surrounded by a stator 680 and a stator housing 683. The
eccentrics 530,540 are
mechanically timed to each other. The rotor 685 and stator 680 drive the
rotation of the drill rod
600. The rotor 685 and stator 680 can also be configured to drive torsional
vibration of the pipe,
allowing the pile 600 to not rotate but oscillate instead. The drill bit 630
oscillates rotationally.
The torsional modes operate at different frequencies than the vertical
oscillations, allowing the
bit 630 to impact at different locations for each vertical oscillation.
100981 FIG. 42 shows (B) a plot of displacement amplitude and (C) acceleration
of the head and
bit versus frequency. (A) The length of pipes can also be selected. The
resonance conditions are
displayed with a dashed line, and a potential operating point is defined as a
long dash. The
operating point has a recommended bit-to-head amplitude ratio, allowing energy
to be delivered
at the bit while minimizing the acceleration impact at the sonic head. Because
this condition can
be in the unstable operating range, standard hydraulically driven rigs cannot
operate under this
condition.
100991 In certain embodiments, the resonance-enabled drill comprises two sets
of counterrotating
eccentrics. Each set spins at the same frequency, with one set, phased
differently from the other
set. In certain embodiments, at startup, the eccentrics are driven at 180 out
of phase from one
another, which cancels all vertical forces. The vertical force amplitude is
adjusted by changing
the phase between the two sets of eccentrics. As the eccentric's phase
approaches 00, the force
approaches 100% force, which is the total force of the four eccentrics
(m*r*0o2), where 'm' is the
mass of the eccentric, 'r' is the distance from the center of rotation to the
center of mass of the
eccentric, and 'co' is the angular speed of the eccentric rotation.
101001 Commercially-available eccentric-driven drills use one set of
eccentrics and operate at
full force. In certain embodiments, the drill comprises a knob which an
operator can use while
drilling to adjust the input force amplitude to the drill. The operator can
operate on or near
resonance and then adjust the input force amplitude until the desired
operating conditions are
met. The adjustment of the input force amplitude changes the phase between the
two pairs of
eccentrics. The desired operating conditions include, but are not limited to,
head acceleration, bit
acceleration, input power, stress state within the system, penetration rate,
energy transferred into
and stored in various sub-systems, etc. The acceleration is related to the
displacement, velocity,
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and jerk through the frequency of oscillation, and any of these can also be
used. The stress state
in the system can be maximum, mean, amplitude, etc.
[0101] In certain embodiments, torsional modes for the drill string use a
rotary motor as the
torsional driver. The torsional resonant modes are similar to the axial
resonant modes. During
operation, the torsional motor drives the oscillations at different
frequencies, permitting the bit to
impact at different rotational locations with each blow. The buttons on the
bit hit virgin material
and did not impact the same location. Also, the rotation oscillation acts as a
paddle to loosen
materials, such as clays, and move the loosened materials during drilling.
[0102] In certain embodiments, the drill comprises two classes of force
generators, wherein the
one or more voice coil actuators are tuned to a first frequency range and the
one or more
eccentrics are tuned to a second frequency range.
Drill Bit Plug
[0103] When drilling in soil, such as non-cemented clay, sand, and the like,
the most common
configuration for geotechnical drilling, the drill bit is selected
accordingly. In these
embodiments, the drill bit comprises tungsten carbide, steel with tungsten
carbide inclusions or
pellets, or the like. In certain embodiments, the drill bit is configured with
an aggressive
geometry to tear off and remove soil.
[0104] When encountering a boulder or hard layer, the conventional drill bit
will be unable to
progress and wear off rapidly. The sonic bit plug is a downhole wireline tool
that latches into the
bottom hole assembly (BHA) and expands underneath the conventional drill bit
to the full string
diameter or slightly more. Sonic motion is activated, and the pushdown force
is applied to the
drill string. The borehole can be progressed over a short penetration without
rotation or
circulation.
[0105] The sonic generator can be powered with air or fluid pressure or
electric power.
[0106] In certain embodiments, rotation may remove the cuttings underneath the
bit. The whole
string can be gently rotated with a wireline bit-plug inside. Alternatively,
the sonic bit plug could
include a rotation capability, such as powered by electricity or air.
[0107] In certain embodiments, circulation cools the drill bit and evacuates
the cuttings from the
borehole. When present, circulation may be achieved through reverse
circulation by injecting air
at the bottom but inside the drill string at the top of the sonic bit plug.
Reversed circulation is
effective but may generate static pressure in the borehole slightly lower than
the ambient
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hydrostatic, destabilizing the borehole. Reversed circulation cannot be
applied to some types of
soils, such as sand or highly fragmented rock. In certain embodiments, the
sonic bit plug is
pulled out of the borehole, and the borehole is cleaned up by gentle rotation
with low Weight on
Bit (WoB). In this instance, conventional fluid circulation and reaming may
also be performed.
Interface
101081 Commercially available drills have digital displays or analog displays
that give the
drilling operator the drill frequency and head acceleration but cannot be
configured to display the
resonance state. In certain embodiments, the resonance-enabled drill comprises
a gauge
configured to display information to the operator when the drill is on or near
resonance. To be
clear, the gauge continously displays information, not just when the drill is
on or near resonance.
The guauge can indicate to the operator when the drill is operating on or near
resonance. For
example, the gauge displays to an operator where mechanical resonance is
located compared to
operating conditions of the drill. In certain embodiments, the drill is no
longer at resonance and
the gauges displays information on the stress state and safe operating
conditions of the drill. In
certain embodiments, the display comprises a list or visual cues of the
current system setup's
resonant frequencies. In certain embodiments, the display is digital, analog,
or a combination
thereof.
101091 Commercially available drills do not indicate what the bit is doing. In
certain
embodiments, the resonance-enabled drill comprises a gauge configured to
display the amplitude
of the drill bit to the operator. The higher the drill bit motion, the better
penetration. In these
embodiments, the drill shows the bit amplitude to the operator. In certain
embodiments, the
resonance-enabled drill further comprises a secondary gauge configured to show
the ratio of bit
motion to the sonic head motion. In many situations, the operator is
recommended to maximize
this ratio. Commercially available drills only present the penetration rate
and sound to the
operator to describe the drill's vibratory state. These indicators are
misleading because the sound
is only generated by motion at the sonic head and is not a good indicator of
bit motion.
101101 Based on system parameters and the operating conditions, stress states
are also estimated
and configured to display on a gauge for the operator in certain embodiments.
Failures are
common because the readout to the operator is only at the sonic head. Still,
with various drilling
conditions, bit and bottom hole assembly configurations, and lengths and
geometry of pipes, the
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stress states change. Therefore, the same amplitude of motion at the sonic
head can generate
drastically different stress conditions below ground.
101111 The displays in commercially available drills show the total power
delivered to the sonic
head for performing work. The total power is broken into real and reactive
power. The real
power is what the system uses to do work, such as drilling. The reactive power
drives the drill bit
may be unused and reflected onto the driver, causing high power input. In
certain embodiments,
the resonance-enabled drill is configured to display the power components of
the drill to the
operator. These components include, but are not limited to, useful power,
power delivered at the
bit, power absorbed along the drill string's length, energy stored in the
drill, and wasted power
(reactive power).
101121 During penetration, the drill bit may become a node, coupled with and
fused to the
workpiece. As the resonant condition changes, the resonance-enabled drill has
a fixed node at the
bottom of the string. When this occurs, the drill bit motion goes to zero or
near zero, and
penetration stops. When the penetration slows or ceases, the resonance-enabled
drill is
configured to display potential problems with options to remedy the lower-than-
desired
penetration rate. For example, when penetration is slowed or ceased, the
resonance-enabled drill
is configured to indicate to the operator that the weight on the bit should be
reduced. In other
saturations, the resonance-enabled drill may indicate when the weight on the
bit is too great,
causing potential fusing of the bit or damage to the workpiece if a sample is
being taken. This
indication may include a shift in the resonant frequency or be calculated from
the drill's
measurements. A list of resonant frequencies with the bit fused to the bottom
also helps the
operator because those are the resonant frequencies to operate on if the
operator does not know
what they are.
101131 Based on the drilling configuration and system, the resonance-enabled
drill is also
configured to display safe operating frequencies for the operator in certain
embodiments. If the
operator tries to operate outside the safe operating ranges, then the
resonance-enabled drill
indicated such to the operator.
101141 FIG. 26 shows a meter that displays the current state of the drill bit
compared to
decoupled and fusion. A recommended operating condition exists between the bit
decoupled state
(where the drill bit is not engaged with the workpiece) and fusion (where the
drill bit acts as a
node or fused to the workpiece). The indicator displays the system operator
where the system is
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operating compared to the recommended conditions and if it is approaching bit
decoupling or
fusion. The displayed information is referred to as the critical weight on
bit.
101151 FIG. 27 shows a resonance-enabled machine configured as a drill with a
voice coil-driven
system at the sonic head. An internal force reflection mass 230 reacts to the
opposing forces from
the voice coil independent of the ground. The system uses the inertia of the
reflection mass to
react to the force imparted on the sonic head without transmitting the force
to the housing.
Sensor
101161 The sonic drill is a resonant system. When the system is operated on
mechanical
resonance, the system has a low impedance, which means it has a high resultant
output compared
to the input. The low impedance, allows the system to become a sensor and the
system can be
monitored through measurements than can be used to calculate changes in the
boundary
conditions, energy absorption, and damage to the system. An example, is when a
force is applied
at the sonic head that applies a very large weight on bit. The very large
weight on bit is enough to
fuse the bit with the soil. The boundary condition changes based on the new
boundary condition
at the bit. There will be a new resonant frequency based on the soil stiffness
at the drill bit. The
systems new measured phase between the input force amplitude and the resultant
head
acceleration oscillation can be used to calculate the soil stiffness at the
drill bit.
101171 The preceding description is given for clearness of understanding only.
No unnecessary
limitations should be understood, as modifications within the disclosure's
scope may be apparent
to those having ordinary skill in the art. Throughout the specification, where
compositions are
described as including components or materials, it is contemplated that the
compositions can also
consist essentially of, or consist of, any combination of the recited
components or materials,
unless described otherwise. Likewise, where methods are described as including
steps, it is
contemplated that the methods can also consist essentially of, or consist of,
any combination of
the recited steps, unless described otherwise. The disclosure illustratively
disclosed herein
suitably may be practiced in the absence of any element or step which is not
specifically
disclosed herein.
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EXAMPLES
Example 1
[0118] Referring to FIG. 8, the resonance-enabled corer operated at zero or
near-zero alternating
force transmitted to frame during operation. When operating the device of FIG.
8 with a
measured 60 g ( 588 m/s2) of oscillation acceleration at the second sonic
head and drawing an
average of 120 W, the system cored a 1" diameter (2.54 cm) hole with a 0.5
core in a 3" thick
(7.62 cm) piece of sandstone in under 3 minutes.
Example 2
[0119] Testing was performed on a GeoProbeTM 8150 LS using 40 ft of 4" drill
pipe and a coring
bit. The coring was performed in a riverbed with various sizes of gravel,
boulders, and sand. If
too much weight was added to the bit by drill pipe, head weight, or push down
force fusion was
initiated at the bit.
[0120] FIG. 29 displays that when the sonic drill was operated at a nominally
constant frequency
of 120 Hz between 245 seconds and 250 seconds, the weight on the bit affected
the system
performance. Counterintuitively, less weight on a bit increased the
penetration rate.
[0121] In FIGS. 30 and 31, the contrasting solid arrows XYX and dashed arrows
XYZ show a
higher penetration rate XYX was observed when the weight on bit was below the
critical weight
on bit. Conversely, when the weight on bit exceeded the critical weight on
bit, the system's
penetration rate decreased along with the subsequent acceleration. See FIG.
29.
[0122] FIG. 32 displays the relative push-and-pull forces from the hydraulic
cylinder of the sonic
drill that lift and push down the sonic drill. The observed critical weight on
the bit line was
displayed. Here, by reducing the weight on the bit, the resultant system
acceleration increased,
resulting in higher energy transfer to the bit for higher penetration rates.
[0123] FIG. 33 shows the resonance meter gauge readings during testing with a
GeoProbeTM
8150 LS using 40 ft of 4- drill pipe and a coring bit. As the frequency was
increased from 60 Hz
to operation at 120 Hz, the gauge went through resonance the drill was
operated above
resonance.
[0124] A gauge displays the difference between phase estimate from the model
for the no
coupling at the bit and the actual measurement. As the phase deviates, the
gauge moves based on
the coupling caused by the weight on the bit. The gauge has a cutoff between 5
and 45 degrees
for the critical weight on bit. The gauge has a green zone between 0 and 45
degrees and, on some
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applications, a yellow zone between a value between 0 and 45 degrees and 45
degrees. After 45
degrees or the determined cutoff for the critical weight on the bit, the gauge
will be red,
indicating that the controller has exceeded the critical weight on the bit.
Example 3
101251 Referring to FIG. 34, the sonic drill system was continuous with
boundary conditions on
each end. The boundary condition at the top of the drill string comprised the
sonic driver internal
force, sonic head mass, input force, damping force, and the air spring or
isolator force. The top
boundary condition can be expressed as Equation 1:
A du(0,t) d2u(0,t) du(0,t)
E ds1-1 ds insh a + cds at k asu( t) sin(oft)
Equation 1
a x t2
where Irish is the mass of the sonic head, cds is the damping at the sonic
head, kos is the spring rate
at the sonic head, Fo is the input force amplitude, COf is the input angular
frequency of the input
force, t is the time, u is the motion at any point along the x-axis, Eds is
the elastic modulus of the
drill string, and Ads is the cross-sectional area of the drill string.
101261 The boundary condition at the bit end of the drill string comprised the
bit mass and strata
coupling internal force, strata damping force, and strata restoring force. The
bottom boundary
condition can be expressed as Equation 2:
A aU(Lds,t) 32U(L d5,t) alta,ds,t) ,
E dSlidS dx = nldb dtz Cdb dt
tcdbU(Lds, t) Equation 2
where mdb is the mass of the drill bit, Cdb is the damping at the drill bit,
kdb is the stiffness at the
drill bit, and Lds is the length of the drill system.
101271 The spring rate at the drill bit was minimal when the bit was free. The
resonant frequency
was lowest compared to when the bit interacted with the soil. Assuming
different soil types of
dense sand (1250 lbf*in-3 (3.38 x 108 N*m-3)), extremely stiff clay (4680
lbf*in-3 (1.27 x 109
N*m')), and granite (rock, 1.58 x 106 lbf*in-3 (4.28 x 1011N*m3)). The
equivalent spring rate
onto the bit was the values above multiplied by the bit frontal area.
101281 The phase between the input force at the sonic head and the resultant
acceleration of the
sonic head was measured. The critical weight on the bit was defined when the
weight onto the bit
during oscillation coupled with the soil/strata being drilled and the boundary
condition at the bit
changed because the soil stiffness acted onto the bit. If the bit were
suspended, the bit impacted
the soil/strata and did not couple but instead received quick transient
impulses from the short
contact with the strata each cycle. If the sonic drill were operating under
the critical weight on
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the bit, the drill had equivalent phase readouts as the model without spring
coupling at the bit for
the drill during drilling operations. As the bit started to interact enough
with the soil, where the
soil stiffness acted as a boundary condition onto the sonic drill system at
the drill bit, the
resultant phase started to shift.
[0129] A commercial sonic drill has been modeled with 40 feet of drill pipe, a
2-foot stub, and a
drill bit on the end. The sonic drill modeled with a minimal spring rate on
the drill bit provided a
measured phase reading similar to FIG. 34. At -90 of phase difference between
the input force
and the resultant acceleration at the sonic head, the system is on mechanical
resonance (Point A
on FIG. 34). The input force and velocity are in phase with one another. For
this example, the
system operated at ¨104.5 Hz. If the system is held operating at ¨104.5 Hz and
additional
downforce is applied, which applied more weight on the bit, the downforce may
change if the
soil stiffness coupling is enough.
[0130] When the weight on the bit was too great, the bit coupled with the soil
or strata. The soil
stiffness influenced the bit. If the weight on the bit was very great, the bit
fully coupled to the
soil or strata, and the soil stiffness acted as a spring on the bit. Here, the
bit fused onto the soil
and became a node. This transition took the bit from a freer boundary
condition to a fixed
boundary condition. If the soil or strata is rock, the soil stiffness is so
great that it allows no
motion at the bit.
[0131] If the soil is dense sand and enough weight on bit is applied that the
drill bit is fused with
the soil so that all the soil stiffness is pushing on the drill bit, then the
boundary of the system
changes and the measured phase changes based on the soil stiffness. At the
point of fusing with
dense sand, the measured phase reads -46 , shifted from Point A to Point B in
FIG. 34, while the
system is still operating at the same frequency. The system's resonant
frequency has shifted up to
106.5 Hz by changing the boundary condition. With the bit fused, the system
has lost the ability
to dissipate energy by drilling through the strata. Instead, the system has to
dissipate the energy
within the system. In many cases, the system cannot dissipate energy, and the
oscillations grow
until failure occurs. If the soil stiffness is greater than dense sand, as
with stiff clay, the same
conditions will occur, but the phase shift is greater than that of dense sand.
[0132] With stiff clay, the resonant frequency can shift from 104.5 Hz to 112
Hz, and the phase
measured at 104.5 Hz now drops to -10 , a shift from Point A to Point C in FIG
34. Hard rock is
an extreme case. If drilling through granite, the phase will shift above the
150 Hz operating range
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of the drill, and the phase will be within 100 of -180 out of phase, which is
the case when the
system is very far from mechanical resonance, shift from A to D in FIG 35.
101331 From these plots, with soils with lower soil stiffness, sands, and low
stiffness clays, the
weight applied to the bit can be greater than the systems with large soil
stiffness, high stiffness
clays, and rock. Because the system behaves similarly with the low weight on
the bit with the
low stiffness clays and sands, whereas pushing up to the critical weight on
bit allows motion at
the drill bit to perform drilling, and the system performs as intended with a
free boundary
condition at the drill bit. However, with stiff clays, the weight on the bit
needs to be more closely
monitored. After all, it can become fused, and then the drill will be in a
refusal state where the bit
cannot move because it has fused to the boundary condition. The resonant
condition has shifted,
but the resonant condition is the new boundary condition where the bit is
fused with the strata,
making it impossible to uncouple the drill bit from the strata once fusing
has. As the soil stiffness
increases, less weight on bit is required for fusing. Therefore, less weight
on bit should be used
when drilling through stiff clays than sands and even less weight when
drilling through rock than
clays.
101341 If the weight on bit is intentionally applied large enough to provide
fusing of the drill bit
to the soil, then the drill system may be used as a sensor to detect the
change in system response
of phase difference between the input force and the resultant acceleration at
the sonic head to
determine the soil stiffness. In FIG. 34, the system responses change because
of the soil type and
this method was described above to determine the critical weigh on bit, but
the measured phase
can be used to calculate the soil stiffness. One such method is to create a
curve of the change is
drill phase performance vs. the soil stiffness and this can be used to
determine the type of soil at
the drill bit.
101351 The practice of a method disclosed herein, and individual steps
thereof, can be performed
manually and/or with the aid of or automation provided by electronic
equipment. Although
processes have been described concerning embodiments, a person of ordinary
skill in the art will
readily appreciate that other ways of performing the methods' acts may be
used. For example, the
order of various of the steps may be changed without departing from the
method's scope or spirit
unless described otherwise. Some of the individual steps can also be combined,
omitted, or
further subdivided into additional steps.
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101361 It is appreciated that certain features of the invention, which are,
for clarity, described in
the context of separate embodiments, may also be provided in combination in a
single
embodiment. Various features of the invention, which are, for brevity,
described in the context of
a single embodiment, may also be provided separately or in any suitable
subcombination. All
patents, publications, and references cited herein are fully incorporated by
reference. In case of
conflict between the present disclosure and incorporated patents,
publications, and references,
the present disclosure should control.
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