U.S. patent application number 16/152732 was filed with the patent office on 2019-04-11 for electric powered hydraulic fracturing system without gear reduction.
This patent application is currently assigned to U.S. Well Services, LLC. The applicant listed for this patent is U.S. Well Services, LLC. Invention is credited to Jared Oehring.
Application Number | 20190106970 16/152732 |
Document ID | / |
Family ID | 65993026 |
Filed Date | 2019-04-11 |
United States Patent
Application |
20190106970 |
Kind Code |
A1 |
Oehring; Jared |
April 11, 2019 |
ELECTRIC POWERED HYDRAULIC FRACTURING SYSTEM WITHOUT GEAR
REDUCTION
Abstract
Embodiments include a hydraulic fracturing system for fracturing
a subterranean formation including an electric pump fluidly
connected to a well associated with the subterranean formation and
powered by at least one electric motor, and configured to pump
fluid into a wellbore associated with the well at a high pressure
so that the fluid passes from the wellbore into the subterranean
formation and fractures the subterranean formation. The system also
includes at least one generator electrically coupled to the
electric motor so as to generate electricity for use by the
electric pump. In the system, a shaft of the motor is directly
coupled to a crankshaft of the pump without an intermediate gear
reduction system such that the shaft of the motor rotates at
substantially the same speed as the crankshaft of the pump.
Inventors: |
Oehring; Jared; (Houston,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
U.S. Well Services, LLC |
Houston |
TX |
US |
|
|
Assignee: |
U.S. Well Services, LLC
Houston
TX
|
Family ID: |
65993026 |
Appl. No.: |
16/152732 |
Filed: |
October 5, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62568723 |
Oct 5, 2017 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 43/26 20130101 |
International
Class: |
E21B 43/26 20060101
E21B043/26 |
Claims
1. A hydraulic fracturing system for fracturing a subterranean
formation comprising: an electric pump fluidly connected to a well
associated with the subterranean formation and powered by at least
one electric motor, and configured to pump fluid into a wellbore
associated with the well at a high pressure so that the fluid
passes from the wellbore into the subterranean formation and
fractures the subterranean formation; at least one generator
electrically coupled to the electric motor so as to generate
electricity for use by the electric pump; wherein a shaft of the
motor is directly coupled to a crankshaft of the pump without an
intermediate gear reduction system such that the shaft of the motor
rotates at substantially the same speed as the crankshaft of the
pump.
2. The system of claim 1, further comprising: a coupling device
connecting the shaft of the motor to the crankshaft.
3. The system of claim 2, wherein the coupling device is a flexible
coupling device or a rigid coupling device.
4. The system of claim 2, wherein the coupling device is at least
one of a beam coupling, a bellows coupling, a chain coupling, a jaw
coupling, a diaphragm coupling, a disc coupling, a gear coupling, a
grid coupling, an Oldham coupling, a Schmidt coupling, or clamping
coupling.
5. The system of claim 1, further comprising: a variable frequency
drive connected to the at least one electric motor to control the
speed of the at least one electric motor.
6. The system of claim 1, wherein the at least one generator
comprises one of a turbine generator or a reciprocating engine
generator, or a combination thereof.
7. The system of claim 1, wherein the electric pump comprises
limited gearing.
8. A hydraulic fracturing system for fracturing a subterranean
formation comprising: an electric pump fluidly connected to a well
associated with the subterranean formation and configured to pump
fluid into a wellbore associated with the well at a high pressure
so that the fluid passes from the wellbore into the subterranean
formation and fractures the subterranean formation; at least one
electric motor providing operational energy to the electric pump;
at least one generator electrically coupled to the electric motor
so as to generate electricity for use by the electric pump; a
variable frequency drive connected to the at least one electric
motor to control the speed of the at least one electric motor;
wherein a shaft of the motor is directly coupled to a crankshaft of
the pump such that the shaft of the motor rotates at substantially
the same speed as the crankshaft of the pump.
9. The system of claim 8, further comprising: a coupling device
connecting the shaft of the motor to the crankshaft.
10. The system of claim 9, wherein the coupling device is a
flexible coupling device or a rigid coupling device.
11. The system of claim 9, wherein the coupling device is at least
one of a beam coupling, a bellows coupling, a chain coupling, a jaw
coupling, a diaphragm coupling, a disc coupling, a gear coupling, a
grid coupling, an Oldham coupling, a Schmidt coupling, or clamping
coupling.
12. The system of claim 1, wherein the at least one generator
comprises one of a turbine generator or a reciprocating engine
generator, or a combination thereof.
13. The system of claim 1, wherein the electric pump comprises
limited gearing.
14. The system of claim 13, wherein the limited gearing is internal
to the electric pump.
15. The system of claim 13, wherein the limited gearing is external
to the electric pump.
16. A hydraulic fracturing system for fracturing a subterranean
formation comprising: an electric pump fluidly connected to a well
associated with the subterranean formation and configured to pump
fluid into a wellbore associated with the well at a high pressure
so that the fluid passes from the wellbore into the subterranean
formation and fractures the subterranean formation; at least one
electric motor providing operational energy to the electric pump; a
variable frequency drive connected to the at least one electric
motor to control the speed of the at least one electric motor;
wherein a shaft of the motor is directly coupled to a crankshaft of
the pump such that the shaft of the motor rotates at substantially
the same speed as the crankshaft of the pump and a torque output of
the at least one electric motor is directly transmitted to the
electric pump.
17. The system of claim 16, further comprising: a coupling device
connecting the shaft of the motor to the crankshaft.
18. The system of claim 17, wherein the coupling device is a
flexible coupling device or a rigid coupling device.
19. The system of claim 17, wherein the coupling device is at least
one of a beam coupling, a bellows coupling, a chain coupling, a jaw
coupling, a diaphragm coupling, a disc coupling, a gear coupling, a
grid coupling, an Oldham coupling, a Schmidt coupling, or clamping
coupling.
20. The system of claim 1, further comprising: at least one
generator electrically coupled to the electric motor so as to
generate electricity for use by the electric pump, wherein the at
least one generator comprises one of a turbine generator or a
reciprocating engine generator, or a combination thereof.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and the benefit of
co-pending U.S. Provisional Application Ser. No. 62/568,723 filed
Oct. 5, 2017 titled "ELECTRIC POWERED HYDRAULIC FRACTURING SYSTEM
WITHOUT GEAR REDUCTION" the full disclosure of which is hereby
incorporated herein by reference in its entirety for all
purposes.
BACKGROUND
1. Technical Field
[0002] This disclosure relates generally to hydraulic fracturing
and more particularly to systems and methods for simplifying
pumping components.
2. Background
[0003] With advancements in technology over the past few decades,
the ability to reach unconventional sources of hydrocarbons has
tremendously increased. Horizontal drilling and hydraulic
fracturing are two such ways that new developments in technology
have led to hydrocarbon production from previously unreachable
shale formations. Hydraulic fracturing (fracturing) operations
typically require powering numerous components in order to recover
oil and gas resources from the ground. For example, hydraulic
fracturing usually includes pumps that inject fracturing fluid down
the wellbore, blenders that mix proppant into the fluid, cranes,
wireline units, and many other components that all must perform
different functions to carry out fracturing operations.
[0004] Typical fracturing operations utilize diesel engines to
power fracturing pumps to deliver high pressure fracturing fluid
into the formation. These diesel engines are typically coupled to a
transmission and gear box (e.g., gear reducer) to step down the
operation of the diesel engine compared to the operating parameters
of the pump. A typical system may include a gear ratio of 6.353:1.
This additional equipment adds cost and complexity to the overall
system. The pumping units weigh more and cost more to ship.
Additionally, the added components may be more prone to damage.
[0005] FIG. 1 is a block diagram of an embodiment of a pump
arrangement 100 having one or more disadvantages described above.
For example, the pump 102 includes an internal gear reduction
system 104. The pump 102 is coupled to a transmission 106, which
receives motive power from a diesel engine 108. This diesel engine
may be loud or have significant environmental emissions.
Additionally, the components such as the transmission 106 and the
gear reduction system 104 add weight and complexity to the
unit.
SUMMARY
[0006] Applicant recognized the problems noted above herein and
conceived and developed embodiments of systems and methods,
according to the present disclosure, for operating electric
fracturing pumps.
[0007] In an embodiment a hydraulic fracturing system for
fracturing a subterranean formation includes an electric pump
fluidly connected to a well associated with the subterranean
formation and powered by at least one electric motor, and
configured to pump fluid into a wellbore associated with the well
at a high pressure so that the fluid passes from the wellbore into
the subterranean formation and fractures the subterranean
formation. The system also includes at least one generator
electrically coupled to the electric motor so as to generate
electricity for use by the electric pump. In the system, a shaft of
the motor is directly coupled to a crankshaft of the pump without
an intermediate gear reduction system such that the shaft of the
motor rotates at substantially the same speed as the crankshaft of
the pump.
[0008] In an embodiment a hydraulic fracturing system for
fracturing a subterranean formation includes an electric pump
fluidly connected to a well associated with the subterranean
formation and configured to pump fluid into a wellbore associated
with the well at a high pressure so that the fluid passes from the
wellbore into the subterranean formation and fractures the
subterranean formation. The system includes at least one electric
motor providing operational energy to the electric pump. The system
also includes at least one generator electrically coupled to the
electric motor so as to generate electricity for use by the
electric pump. The system further includes variable frequency drive
connected to the at least one electric motor to control the speed
of the at least one electric motor. In the system, a shaft of the
motor is directly coupled to a crankshaft of the pump such that the
shaft of the motor rotates at substantially the same speed as the
crankshaft of the pump.
[0009] In an embodiment a hydraulic fracturing system for
fracturing a subterranean formation includes an electric pump
fluidly connected to a well associated with the subterranean
formation and configured to pump fluid into a wellbore associated
with the well at a high pressure so that the fluid passes from the
wellbore into the subterranean formation and fractures the
subterranean formation. The system also includes at least one
electric motor providing operational energy to the electric pump.
The system includes a variable frequency drive connected to the at
least one electric motor to control the speed of the at least one
electric motor. In the system, a shaft of the motor is directly
coupled to a crankshaft of the pump such that the shaft of the
motor rotates at substantially the same speed as the crankshaft of
the pump and a torque output of the at least one electric motor is
directly transmitted to the electric pump.
BRIEF DESCRIPTION OF DRAWINGS
[0010] The foregoing aspects, features, and advantage of
embodiments of the present disclosure will further be appreciated
when considered with reference to the following description of
embodiments and accompanying drawings. In describing embodiments of
the disclosure illustrated in the appended drawings, specific
terminology will be used for the sake of clarity. However, the
disclosure is not intended to be limited to the specific terms
used, and it is to be understood that each specific term includes
equivalents that operate in a similar manner to accomplish a
similar purpose.
[0011] FIG. 1 is a block diagram of a prior art diesel powered
pumping system;
[0012] FIG. 2 is a block diagram of an embodiment of a hydraulic
fracturing system, in accordance with embodiments of the present
disclosure;
[0013] FIG. 3 is a block diagram of an embodiment of an electric
powered pump assembly, in accordance with embodiments of the
present disclosure; and
[0014] FIG. 4 is a block diagram of an embodiment of an electric
powered pump assembly, in accordance with embodiments of the
present disclosure.
DETAILED DESCRIPTION
[0015] The foregoing aspects, features, and advantages of the
present disclosure will be further appreciated when considered with
reference to the following description of embodiments and
accompanying drawings. In describing the embodiments of the
disclosure illustrated in the appended drawings, specific
terminology will be used for the sake of clarity. However, the
disclosure is not intended to be limited to the specific terms
used, and it is to be understood that each specific term includes
equivalents that operate in a similar manner to accomplish a
similar purpose.
[0016] When introducing elements of various embodiments of the
present disclosure, the articles "a", "an", "the", and "said" are
intended to mean that there are one or more of the elements. The
terms "comprising", "including", and "having" are intended to be
inclusive and mean that there may be additional elements other than
the listed elements. Any examples of operating parameters and/or
environmental conditions are not exclusive of other
parameters/conditions of the disclosed embodiments. Additionally,
it should be understood that references to "one embodiment", "an
embodiment", "certain embodiments", or "other embodiments" of the
present disclosure are not intended to be interpreted as excluding
the existence of additional embodiments that also incorporate the
recited features. Furthermore, reference to terms such as "above",
"below", "upper", "lower", "side", "front", "back", or other terms
regarding orientation or direction are made with reference to the
illustrated embodiments and are not intended to be limiting or
exclude other orientations or directions. Additionally, recitations
of steps of a method should be understood as being capable of being
performed in any order unless specifically stated otherwise.
Furthermore, the steps may be performed in series or in parallel
unless specifically stated otherwise.
[0017] Embodiments of the present disclosure describe an electric
powered pumping assembly with fewer components than a traditional
diesel system for reduced weight and simplified operation. In
certain embodiments, the assembly removes a transmission arranged
between a power generator and the pump. Moreover, in embodiments,
internal gearing or additional gear boxes are also removed.
Accordingly, the assembly generally has a simplified configuration
with reduced weight and fewer components for potential failure
points.
[0018] FIG. 2 is a schematic diagram of an embodiment of a
hydraulic fracturing system 10 that is used for pressurizing a
wellbore 12 to create fractures 14 in a subterranean formation 16
that surrounds the wellbore 12. Included with the system 10 is a
hydration unit 18 that receives fluid from a fluid source 20 via
line 22, and also selectively receives additives from an additive
source 24 via line 26. The additive source 24 can be separate from
the hydration unit 18 as a stand-alone unit, or can be included as
part of the same unit as the hydration unit 18. The fluid, which in
one example is water, is mixed inside of the hydration unit 18 with
the additives. In an embodiment, the fluid and additives are mixed
over a period of time, to allow for uniform distribution of the
additives within the fluid. In the example of FIG. 2, the fluid and
additive mixture is transferred to a blender unit 28 via line 30. A
proppant source 32 contains proppant, which is delivered to the
blender unit 28 as represented by line 34, where line 34 can be a
conveyer. Inside the blender unit 28, the proppant and
fluid/additive mixture are combined to form a fracturing slurry,
which is then transferred to a fracturing pump system 36 via line
38; thus fluid in line 38 includes the discharge of blender unit 28
which is the suction (or boost) for the fracturing pump system
36.
[0019] Blender unit 28 can have an onboard chemical additive
system, such as with chemical pumps and augers. Optionally,
additive source 24 can provide chemicals to blender unit 28; or a
separate and standalone chemical additive system (not shown) can be
provided for delivering chemicals to the blender unit 28. In an
example, the pressure of the slurry in line 38 ranges from around
80 psi to around 100 psi. The pressure of the slurry can be
increased up to around 15,000 psi by pump system 36. A motor 39,
which connects to pump system 36 via connection 40, drives pump
system 36 so that it can pressurize the slurry. In one example, the
motor 39 is controlled by a variable frequency drive ("VFD").
[0020] After being discharged from pump system 36, slurry is pumped
into a wellhead assembly 41. Discharge piping 42 connects discharge
of pump system 36 with wellhead assembly 41 and provides a conduit
for the slurry between the pump system 36 and the wellhead assembly
41. In an alternative, hoses or other connections can be used to
provide a conduit for the slurry between the pump system 36 and the
wellhead assembly 41. Optionally, any type of fluid can be
pressurized by the fracturing pump system 36 to form injection
fracturing fluid that is then pumped into the wellbore 12 for
fracturing the formation 14, and is not limited to fluids having
chemicals or proppant.
[0021] An example of a turbine 44 is provided in the example of
FIG. 2. The turbine can be gas powered, receiving a combustible
fuel from a fuel source 46 via a feed line 48. In one example, the
combustible fuel is natural gas, and the fuel source 46 can be a
container of natural gas or a well (not shown) proximate the
turbine 44. Combustion of the fuel in the turbine 44 in turn powers
a generator 50 that produces electricity. A shaft 52 connects the
generator 50 to the turbine 44. The combination of the turbine 44,
the generator 50, and the shaft 52 define a turbine generator 53.
In another example, gearing can also be used to connect the turbine
44 and generator 50.
[0022] An example of a micro-grid 54 is further illustrated in FIG.
2, and which distributes electricity generated by the turbine
generator 53. Included with the micro-grid 54 is a transformer 56
for stepping down voltage of the electricity generated by the
generator 50 to a voltage more compatible for use by electrically
powered devices in the hydraulic fracturing system 10. In another
example, the power generated by the turbine generator and the power
utilized by the electrically powered devices in the hydraulic
fracturing system 10 are of the same voltage, such as 4160 V, so
that main power transformers are not needed. In one embodiment,
multiple 3500 kVA dry cast coil transformers are utilized.
Electricity generated in generator 50 is conveyed to transformer 56
via line 58. In one example, transformer 56 steps the voltage down
from 13.8 kV to around 600 V. Other step down voltages can include
4,160 V, 480 V, or other voltages.
[0023] The output or low voltage side of the transformer 56
connects to a power bus 60, lines 62, 64, 66, 68, 70, and 71
connect to power bus 60 and deliver electricity to electrically
powered components of the system 10. More specifically, line 62
connects fluid source 20 to bus 60, line 64 connects additive
source 24 to bus 60, line 66 connects hydration unit 18 to bus 60,
line 68 connects proppant source 32 to bus 60, line 70 connects
blender unit 28 to bus 60, and line 71 connects bus 60 to an
optional variable frequency drive ("VFD") 72. Line 73 connects VFD
72 to motor 39. In one example, VFD 72 can be used to control
operation of motor 39, and thus also operation of pump 36.
[0024] In an example, additive source 24 contains ten or more
chemical pumps for supplementing the existing chemical pumps on the
hydration unit 18 and blender unit 28. Chemicals from the additive
source 24 can be delivered via lines 26 to either the hydration
unit 18 and/or the blender unit 28. In one embodiment, the elements
of the system 10 are mobile and can be readily transported to a
well site adjacent the wellbore 12, such as on trailers or other
platforms equipped with wheels or tracks.
[0025] FIG. 3 is a schematic diagram of an embodiment of a pump 80
utilized in a fracturing operation. The illustrated pump 80 is
powered by the generator 50, which may be part of the turbine
generator 53 in certain embodiments. The pump 80 includes the motor
39 which transmits rotational force to the pump 80 via the
electrical power transmitted from the generator 50. In the
illustrated embodiment, the motor 39 is mechanically coupled
directly to a crankshaft 82 of the pump 80, for example via a
coupling device 84. The coupling device 84 may be rigid or flexible
and arranged to align a shaft 86 of the motor 39 and the crankshaft
82, or to absorb alignment inaccuracies. In various embodiments,
the coupling device 84 may include a beam, a bellows, a chain, a
jaw, a diaphragm, a disc, a gear, a grid, an Oldham, a Schmidt, a
clamping, or the like. It should be appreciated that the coupling
device 84 may be omitted in certain embodiments. As illustrated,
components such as a transmission and/or gear box (e.g., gear
reducer) have been removed from the system in FIG. 3. Accordingly,
the pump 80 and associated equipment, which may be mounted on one
or more trailers, will have a reduced weight, thereby decreasing
the cost of transporting the units to different well sites.
Furthermore, the elimination of components such as the transmission
and gear box, which may include complex moving parts and/or
auxiliary fluid systems, reduces the complexity of the overall
systems and improves reliability by eliminating components that may
be prone to damage or breakdown. Additionally, maintenance costs
may be reduced because there are fewer components to maintain.
[0026] In the illustrated embodiment, the pump 80 is coupled to the
motor 39, which is coupled to the VFD 72 and the generator 50. As
described above, the VFD may control operation of the motor 39,
which thereby regulates operation of the pump. It should be
appreciated that the generator 50 may be a turbine generator or any
other type of electric power source. For example, in embodiments
the VFD may be coupled to a grid or other power supply.
Accordingly, the embodiment illustrated in FIG. 3 enables the
crankshaft 82 of the pump 80 to rotate at substantially the same
speed as the shaft 86 of the motor 39. As such, the speed of the
motor 39 may be adjusted in order to change operating parameters of
the pump 80. In various embodiments, the pump 80 may be configured
to provide a sufficient output pressure at a speed that is
compatible with operation of the motor 39. Accordingly, additional
components such as the above-described gear reduction may be
removed, providing a more streamlined system that weighs less and
also eliminates potential failure points.
[0027] FIG. 4 is a schematic diagram of an embodiment of the pump
80 which includes gearing 90 for spacing. As described above, this
configuration removes the transmission and therefore produces a
smaller, lighter, and less complicated pumping arrangement. In
certain embodiments, the gearing 90 may be referred to as limited
gearing which is utilized for spacing or for other components, such
as lube oil. The gearing 90 may be internal to the pump 90, as
illustrated in FIG. 4, or may be an external component. The
illustrated embodiment also includes the coupling device 84, which
may be eliminated in certain embodiments.
[0028] The foregoing disclosure and description of the disclosed
embodiments is illustrative and explanatory of the embodiments of
the invention. Various changes in the details of the illustrated
embodiments can be made within the scope of the appended claims
without departing from the true spirit of the disclosure. The
embodiments of the present disclosure should only be limited by the
following claims and their legal equivalents.
* * * * *