(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2012/0255734 A1
`(43) Pub. Date:
`Oct. 11, 2012
`Coli et al.
`
`US 20120255734A1
`
`(54) MOBILE, MODULAR, ELECTRICALLY
`POWERED SYSTEM FOR USE IN
`FRACTURING UNDERGROUND
`FORMATIONS
`
`(76) Inventors:
`
`Todd Coli, Calgary (CA); Eldon
`Schelske, Calgary (CA)
`
`(21) Appl. No.:
`
`13/441,334
`
`(22) Filed:
`
`Apr. 6, 2012
`
`Related U.S. Application Data
`(60) Provisional application No. 61/472,861, filed on Apr.
`7, 2011.
`
`Publication Classification
`
`(51) Int. Cl.
`(2006.01)
`E2IB 43/26
`(52) U.S. Cl. ................................... 166/305.1: 166/177.5
`(57)
`ABSTRACT
`The present invention provides a method and system for
`providing on-site electrical power to a fracturing operation,
`and an electrically powered fracturing system. Natural gas
`can be used to drive a turbine generator in the production of
`electrical power. A scalable, electrically powered fracturing
`fleet is provided to pump fluids for the fracturing operation,
`obviating the need for a constant supply of diesel fuel to the
`site and reducing the site footprint and infrastructure required
`for the fracturing operation, when compared with conven
`tional systems.
`
`
`
`47a
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`47
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`is - - - - - - - - - - - - - as - - - - - - - - - - - - w - - - - - - - - - - - - - - - - - - - - -
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`Oct. 11, 2012
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`MOBILE, MODULAR, ELECTRICALLY
`POWERED SYSTEM FOR USE IN
`FRACTURING UNDERGROUND
`FORMATIONS
`
`CROSS REFERENCE TO RELATED
`APPLICATIONS
`
`0001. This application claims the benefit, and priority ben
`efit, of U.S. Provisional Patent Application Ser. No. 61/472,
`861, filed Apr. 7, 2011, titled “MOBILE, MODULAR,
`ELECTRICALLY POWERED SYSTEM FOR USE IN
`FRACTURING UNDERGROUND FORMATIONS, the
`disclosure of which is incorporated herein in its entirety.
`
`BACKGROUND
`
`0002 1. Field of Invention
`0003. This invention relates generally to hydraulic stimu
`lation of underground hydrocarbon-bearing formations, and
`more particularly, to the generation and use of electrical
`power to deliver fracturing fluid to a wellbore.
`0004 2. Description of the Related Art
`0005 Over the life cycle of a typical hydrocarbon-produc
`ing wellbore, various fluids (along with additives, proppants,
`gels, cement, etc. ...) can be delivered to the wellbore under
`pressure and injected into the wellbore. Surface pumping
`systems must be able to accommodate these various fluids.
`Such pumping systems are typically mobilized on skids or
`tractor-trailers and powered using diesel motors.
`0006 Technological advances have greatly improved the
`ability to identify and recover unconventional oil and gas
`resources. Notably, horizontal drilling and multi-stage frac
`turing have led to the emergence of new opportunities for
`natural gas production from shale formations. For example,
`more than twenty fractured intervals have been reported in a
`single horizontal wellbore in a tight natural gas formation.
`However, significant fracturing operations are required to
`recover these resources.
`0007 Currently contemplated natural gas recovery oppor
`tunities require considerable operational infrastructure,
`including large investments in fracturing equipment and
`related personnel. Notably, standard fluid pumps require
`large Volumes of diesel fuel and extensive equipment main
`tenance programs. Typically, each fluid pump is housed on a
`dedicated truck and trailer configuration. With average frac
`turing operations requiring as many as fifty fluid pumps, the
`on-site area, or “footprint, required to accommodate these
`fracturing operations is massive. As a result, the operational
`infrastructure required to Support these fracturing operations
`is extensive. Greater operational efficiencies in the recovery
`of natural gas would be desirable.
`0008. When planning large fracturing operations, one
`major logistical concern is the availability of diesel fuel. The
`excessive Volumes of diesel fuel required necessitates con
`stant transportation of diesel tankers to the site, and results in
`significant carbon dioxide emissions. Others have attempted
`to decrease fuel consumption and emissions by running large
`pump engines on "Bi-Fuel”, blending natural gas and diesel
`fuel together, but with limited success. Further, attempts to
`decrease the number of personnel on-site by implementing
`remote monitoring and operational control have not been
`
`Successful, as personnel are still required on-site to transport
`the equipment and fuel to and from the location.
`
`SUMMARY
`0009 Various illustrative embodiments of a system and
`method for hydraulic stimulation of underground hydrocar
`bon-bearing formations are provided herein. In accordance
`with an aspect of the disclosed subject matter, a method of
`delivering fracturing fluid to a wellbore is provided. The
`method can comprise the steps of providing a dedicated
`Source of electric power at a site containing a wellbore to be
`fractured; providing one or more electric fracturing modules
`at the site, each electric fracturing module comprising an
`electric motor and a coupled fluid pump, each electric motor
`operatively associated with the dedicated source of electric
`power; providing a wellbore treatment fluid for pressurized
`delivery to a wellbore, wherein the wellbore treatment fluid
`can be continuous with the fluid pump and with the wellbore;
`and operating the fracturing unit using electric power from
`the dedicated source to pump the treatment fluid to the well
`bore.
`0010. In certain illustrative embodiments, the dedicated
`Source of electrical power is a turbine generator. A source of
`natural gas can be provided, whereby the natural gas drives
`the turbine generator in the production of electrical power.
`For example, natural gas can be provided by pipeline, or
`natural gas produced on-site. Liquid fuels such as condensate
`can also be provided to drive the turbine generator.
`0011. In certain illustrative embodiments, the electric
`motor can be an AC permanent magnet motor and/or a vari
`able speed motor. The electric motor can be capable of opera
`tion in the range of up to 1500 rpms and up to 20,000 ft/lbs of
`torque. The pump can be a triplex or quintiplex plunger style
`fluid pump.
`0012. In certain illustrative embodiments, the method can
`further comprise the steps of providing an electric blender
`module continuous and/or operatively associated with the
`fluid pump, the blender module comprising: a fluid source, a
`fluid additive source, and a centrifugal blender tub, and Sup
`plying electric power from the dedicated source to the blender
`module to effect blending of the fluid with fluid additives to
`generate the treatment fluid.
`0013. In accordance with another aspect of the disclosed
`Subject matter, a system for use in delivering pressurized fluid
`to a wellbore is provided. The system can comprise: a well
`site comprising a wellbore and a dedicated source of electric
`ity; an electrically powered fracturing module operatively
`associated with the dedicated source of electricity, the elec
`trically powered fracturing module comprising an electric
`motor and a fluid pump coupled to the electric motor, a source
`of treatment fluid, wherein the treatment fluid can be continu
`ous with the fluid pump and with the wellbore; and a control
`system for regulating the fracturing module in delivery of
`treatment fluid from the treatment fluid source to the well
`bore.
`0014. In certain illustrative embodiments, the source of
`treatment fluid can comprise an electrically powered blender
`module operatively associated with the dedicated source of
`electricity. The system can further comprise a fracturing
`trailer at the well site for housing one or more fracturing
`modules. Each fracturing module can be adapted for remov
`able mounting on the trailer. The system can further comprise
`a replacement pumping module comprising a pump and an
`electric motor, the replacement pumping module adapted for
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`removable mounting on the trailer. In certain illustrative
`embodiments, the replacement pumping module can be a
`nitrogen pumping module, or a carbon dioxide pumping mod
`ule. The replacement pumping module can be, for example, a
`high torque, low rate motor or a low torque, high rate motor.
`0015. In accordance with another aspect of the disclosed
`Subject matter, a fracturing module for use in delivering pres
`surized fluid to a wellbore is provided. The fracturing module
`can comprise: an AC permanent magnet motor capable of
`operation in the range of up to 1500 rpms and up to 20,000
`ft/lbs of torque; and a plunger-style fluid pump coupled to the
`motor.
`0016. In accordance with another aspect of the disclosed
`subject matter, a method of blending a fracturing fluid for
`delivery to a wellbore to be fractured is provided. A dedicated
`Source of electric power can be provided at a site containing
`a wellbore to be fractured. At least one electric blender mod
`ule can be provided at the site. The electric blender module
`can include a fluid source, a fluid additive source, and a
`blender tub. Electric power can be supplied from the dedi
`cated source to the electric blender module to effect blending
`of a fluid from the fluid source with a fluid additive from the
`fluid additive source to generate the fracturing fluid. The
`dedicated Source of electrical power can be a turbine genera
`tor. A source of natural gas can be provided, wherein the
`natural gas is used to drive the turbine generator in the pro
`duction of electrical power. The fluid from the fluid source
`can be blended with the fluid additive from the fluid additive
`source in the blender tub. The electric blender module can
`also include at least one electric motor that is operatively
`associated with the dedicated source of electric power and
`that effects blending of the fluid from the fluid source with the
`fluid additive from the fluid additive source.
`0017. In certain illustrative embodiments, the electric
`blender module can include a first electric motor and a second
`electric motor, each of which is operatively associated with
`the dedicated source of electric power. The first electric motor
`can effect delivery of the fluid from the fluid source to the
`blending tub. The second electric motor can effect blending of
`the fluid from the fluid source with the fluid additive from the
`fluid additive source in the blending tub. In certain illustrative
`embodiments, an optional third electric motor may also be
`present, that can also be operatively associated with the dedi
`cated source of electric power. The third electric motor can
`effect delivery of the fluid additive from the fluid additive
`source to the blending tub.
`0.018. In certain illustrative embodiments, the electric
`blender module can include a first blender unit and a second
`blender unit, each disposed adjacent to the other on the
`blender module and each capable of independent operation,
`or collectively capable of cooperative operation, as desired.
`The first blender unit and the second blender unit can each
`include a fluid source, a fluid additive source, and a blender
`tub. The first blender unit and the second blender unit can each
`have at least one electric motor that is operatively associated
`with the dedicated source of electric power and that effects
`blending of the fluid from the fluid source with the fluid
`additive from the fluid additive source. Alternatively, the first
`blender unit and the second blender unit can each have a first
`electric motor and a second electric motor, both operatively
`associated with the dedicated source of electric power,
`wherein the first electric motor effects delivery of the fluid
`from the fluid source to the blending tub and the second
`electric motor effects blending of the fluid from the fluid
`
`source with the fluid additive from the fluid additive source in
`the blending tub. In certain illustrative embodiments, the first
`blender unit and the second blender unit can each also have a
`third electric motor operatively associated with the dedicated
`source of electric power, wherein the third electric motor
`effects delivery of the fluid additive from the fluid additive
`source to the blending tub.
`0019. In accordance with another aspect of the disclosed
`subject matter, an electric blender module for use in deliver
`ing a blended fracturing fluid to a wellbore is provided. The
`electric blender module can include a first electrically driven
`blender unit and a first inlet manifold coupled to the first
`electrically driven blender unit and capable of delivering an
`unblended fracturing fluid thereto. A first outlet manifold can
`be coupled to the first electrically driven blender unit and can
`be capable of delivering the blended fracturing fluid away
`therefrom. A second electrically driven blender unit can be
`provided. A second inlet manifold can be coupled to the
`second electrically driven blender unit and capable of deliv
`ering the unblended fracturing fluid thereto. A second outlet
`manifold can be coupled to the second electrically driven
`blender unit and can be capable of delivering the blended
`fracturing fluid away therefrom. An inlet crossing line can be
`coupled to both the first inlet manifold and the second inlet
`manifold and can be capable of delivering the unblended
`fracturing fluid therebetween. An outlet crossing line can be
`coupled to both the first outlet manifold and the second outlet
`manifold and can be capable of delivering the blended frac
`turing fluid therebetween. A skid can be provided for housing
`the first electrically driven blender unit, the first inlet mani
`fold, the second electrically driven blender unit, and the sec
`ond inlet manifold.
`0020. Other aspects and features of the present invention
`will become apparent to those of ordinary skill in the art upon
`review of the following detailed description in conjunction
`with the accompanying figures.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`0021. A better understanding of the presently disclosed
`subject matter can be obtained when the following detailed
`description is considered in conjunction with the following
`drawings, wherein:
`0022 FIG. 1 is a schematic plan view of a traditional
`fracturing site;
`0023 FIG. 2 is a schematic plan view of a fracturing site in
`accordance with certain illustrative embodiments described
`herein;
`0024 FIG. 3 is a schematic perspective view of a fractur
`ing trailer in accordance with certain illustrative embodi
`ments described herein;
`0025 FIG. 4A is a schematic perspective view of a frac
`turing module in accordance with certain illustrative embodi
`ments described herein;
`0026 FIG. 4B is a schematic perspective view of a frac
`turing module with maintenance personnel in accordance
`with certain illustrative embodiments described herein;
`0027 FIG. 5A is a schematic side view of a blender mod
`ule in accordance with certain illustrative embodiments
`described herein;
`0028 FIG. 5B is an end view of the blender module shown
`in FIG. 4A;
`(0029 FIG.5C is a schematic top view of a blender module
`in accordance with certain illustrative embodiments
`described herein;
`
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`0030 FIG. 5D is a schematic side view of the blender
`module shown in FIG.5C:
`0031 FIG. 5E is a schematic perspective view of the
`blender module shown in FIG. 5C:
`0032 FIG. 6 is a schematic top view of an inlet manifold
`for a blender module in accordance with certain illustrative
`embodiments described herein; and
`0033 FIG. 7 is a schematic top view of an outlet manifold
`for a blender module in accordance with certain illustrative
`embodiments described herein.
`
`DETAILED DESCRIPTION
`0034. The presently disclosed subject matter generally
`relates to an electrically powered fracturing system and a
`system and method for providing on-site electrical power and
`delivering fracturing fluid to a wellbore at a fracturing opera
`tion.
`0035. In a conventional fracturing operation, a “slurry' of
`fluids and additives is injected into a hydrocarbon bearing
`rock formation at a wellbore to propagate fracturing. Low
`pressure fluids are mixed with chemicals, sand, and, if nec
`essary, acid, and then transferred at medium pressure and high
`rate to vertical and/or deviated portions of the wellbore via
`multiple high pressure, plunger style pumps driven by diesel
`fueled prime movers. The majority of the fluids injected will
`be flowed back through the wellbore and recovered, while the
`sand will remain in the newly created fracture, thus “prop
`ping it open and providing a permeable membrane for
`hydrocarbon fluids and gases to flow through so they may be
`recovered.
`0036. According to the illustrative embodiments
`described herein, natural gas (either Supplied to the site or
`produced on-site) can be used to drive a dedicated Source of
`electrical power, Such as a turbine generator, for hydrocar
`bon-producing wellbore completions. A Scalable, electrically
`powered fracturing fleet is provided to deliver pressurized
`treatment fluid, such as fracturing fluid, to a wellbore in a
`fracturing operation, obviating the need for a constant Supply
`of diesel fuel to the site and reducing the site footprint and
`infrastructure required for the fracturing operation, when
`compared with conventional operations. The treatment fluid
`provided for pressurized delivery to the wellbore can be con
`tinuous with the wellbore and with one or more components
`of the fracturing fleet, in certain illustrative embodiments. In
`these embodiments, continuous generally means that down
`hole hydrodynamics are dependent upon constant flow (rate
`and pressure) of the delivered fluids, and that there should not
`be any interruption in fluid flow during delivery to the well
`bore if the fracture is to propagate as desired. However, it
`should not be interpreted to mean that operations of the frac
`turing fleet cannot generally be stopped and started, as would
`be understood by one of ordinary skill in the art.
`0037. With reference to FIG. 1, a site plan for a traditional
`fracturing operation on an onshore site is shown. Multiple
`trailers 5 are provided, each having at least one diesel tank
`mounted or otherwise disposed thereon. Each trailer 5 is
`attached to a truck 6 to permit refueling of the diesel tanks as
`required. Trucks 6 and trailers 5 are located within region A
`on the fracturing site. Each truck 6 requires a dedicated opera
`tor. One or more prime movers are fueled by the diesel and are
`used to power the fracturing operation. One or more separate
`chemical handling skids 7 are provided for housing of blend
`ing tanks and related equipment.
`
`0038. With reference to FIG.2, an illustrative embodiment
`of a site plan for an electrically powered fracturing operation
`on a onshore site is shown. The fracturing operation includes
`one or more trailers 10, each housing one or more fracturing
`modules 20 (see FIG.3). Trailers 10 are located in region B on
`the fracturing site. One or more natural gas-powered turbine
`generators 30 are located in region C on the site, which is
`located a remote distance D from region B where the trailers
`10 and fracturing modules 20 are located, for safety reasons.
`Turbine generators 30 replace the diesel prime movers uti
`lized in the site plan of FIG.1. Turbine generators 30 provide
`a dedicated source of electric power on-site. There is prefer
`ably a physical separation between the natural gas-based
`power generation in region C and the fracturing operation and
`wellbore located in region B. The natural gas-based power
`generation can require greater safety precautions than the
`fracturing operation and wellhead. Accordingly, security
`measures can be taken in region C to limit access to this more
`hazardous location, while maintaining separate safety stan
`dards in region B where the majority of site personnel are
`typically located. Further, the natural gas powered Supply of
`electricity can be monitored and regulated remotely such that,
`if desired, no personnel are required to be within region C
`during operation.
`0039. Notably, the setup of FIG. 2 requires significantly
`less infrastructure than the setup shown in FIG. 1, while
`providing comparable pumping capacity. Fewer trailers 10
`are present in region B of FIG. 2 than the trucks 6 and trailers
`5 in region A of FIG. 1, due to the lack of need for a constant
`diesel fuel supply. Further, each trailer 10 in FIG. 2 does not
`need a dedicated truck 6 and operator as in FIG. 1. Fewer
`chemical handling skids 7 are required in region B of FIG. 2
`than in region A of FIG. 1, as the skids 7 in FIG. 2 can be
`electrically powered. Also, by removing diesel prime movers,
`all associated machinery necessary for power transfer can be
`eliminated, such as the transmission, torque converter, clutch,
`drive shaft, hydraulic system, etc. . . . . and the need for
`cooling systems, including circulating pumps and fluids, is
`significantly reduced. In an illustrative embodiment, the
`physical footprint of the on-site area in region B of FIG. 2 is
`about 80% less than the footprint for the conventional system
`in region A of FIG. 1.
`0040. With reference to the illustrative embodiments of
`FIG. 3, trailer 10 for housing one or more fracturing modules
`20 is shown. Trailer 10 can also be a skid, in certain illustra
`tive embodiments. Each fracturing module 20 can include an
`electric motor 21 and a fluid pump 22 coupled thereto. During
`fracturing, fracturing module 20 is operatively associated
`with turbine generator 30 to receive electric powertherefrom.
`In certain illustrative embodiments, a plurality of electric
`motors 21 and pumps 22 can be transported on a single trailer
`10. In the illustrative embodiments of FIG. 3, four electric
`motors 21 and pumps 22 are transported on a single trailer 10.
`Each electric motor 21 is paired to a pump 22 as a single
`fracturing module 20. Each fracturing module 20 can be
`removably mounted to trailer 10 to facilitate ease of replace
`ment as necessary. Fracturing modules 20 utilize electric
`power from turbine generator 30 to pump the fracturing fluid
`directly to the wellbore.
`0041
`Electrical Power Generation
`0042. The use of a turbine to directly drive a pump has
`been previously explored. In Such systems, a transmission is
`used to regulate turbine power to the pump to allow for speed
`and torque control. In the present operation, natural gas is
`
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`instead used to drive a dedicated power source in the produc
`tion of electricity. In illustrative embodiments, the dedicated
`power source is an on-site turbine generator. The need for a
`transmission is eliminated, and generated electricity can be
`used to power the fracturing modules, blenders, and other
`on-site operations as necessary.
`0043. Grid power may be accessible on-site in certain
`fracturing operations, but the use of a dedicated power Source
`is preferred. During startup of a fracturing operation, massive
`amounts of power are required such that the use of grid power
`would be impractical. Natural gas powered generators are
`more suitable for this application based on the likely avail
`ability of natural gas on-site and the capacity of natural gas
`generators for producing large amounts of power. Notably,
`the potential for very large instantaneous adjustments in
`power drawn from the grid during a fracturing operation
`could jeopardize the stability and reliability of the grid power
`system. Accordingly, a site-generated and dedicated Source of
`electricity provides a more feasible solution in powering an
`electric fracturing system. In addition, a dedicated on-site
`operation can be used to provide power to operate other local
`equipment, including coiled tubing systems, service rigs, etc.
`
`0044. In an illustrative embodiment, a single natural gas
`powered turbine generator 30, as housed in a restricted area C
`of FIG. 2, can generate sufficient power (for example 31 MW
`at 13,800 volts AC power) to supply several electric motors 21
`and pumps 22, avoiding the current need to deliver and oper
`ate each fluid pump from a separate diesel-powered truck. A
`turbine suitable for this purpose is a TM2500+ turbine gen
`erator sold by General Electric. Other generation packages
`could be supplied by Pratt & Whitney or Kawasaki for
`example. Multiple options are available for turbine power
`generation, depending on the amount of electricity required.
`In an illustrative embodiment, liquid fuels such as condensate
`can also be provided to drive turbine generator 30 instead of
`or in addition to, natural gas. Condensate is less expensive
`than diesel fuels, thus reducing operational costs.
`0045 Fracturing Module
`0046. With reference to FIGS. 4A and 4B, an illustrative
`embodiment of fracturing module 20 is provided. Fracturing
`module 20 can include an electric motor 21 coupled to one or
`more electric pumps 22, in certain illustrative embodiments.
`A Suitable pump is a quintiplex or triplex plunger style pump,
`for example, the SWGS-2500 Well Service Pump sold by
`Gardner Denver, Inc.
`0047 Electric motor 21 is operatively associated with tur
`bine generator 30, in certain embodiments. Typically, each
`fracturing module 20 will be associated with a drive housing
`for controlling electric motor 21 and pumps 22, as well as an
`electrical transformer and drive unit 50 (see FIG. 3) to step
`down the voltage of the power from turbine generator 30 to a
`voltage appropriate for electric motor 21. The electrical trans
`former and drive unit 50 can be provided as an independent
`unit for association with fracturing module 20, or can be
`permanently fixed to the trailer 10, in various embodiments. If
`permanently fixed, then transformer and drive unit 50 can be
`scalable to allow addition or subtraction of pumps 22 or other
`components to accommodate any operational requirements.
`0048. Each pump 22 and electric motor 21 are modular in
`nature so as to simplify removal and replacement from frac
`turing module 20 for maintenance purposes. Removal of a
`single fracturing module 20 from trailer 10 is also simplified.
`For example, any fracturing module 20 can be unplugged and
`
`unpinned from trailer10 and removed, and another fracturing
`module 20 can be installed in its place in a matter of minutes.
`0049. In the illustrative embodiment of FIG. 3, trailer 10
`can house four fracturing modules 20, along with a trans
`former and drive unit 50. In this particular configuration, each
`single trailer 10 provides more pumping capacity than four of
`the traditional diesel powered fracturing trailers 5 of FIG. 1,
`as parasitic losses are minimal in the electric fracturing sys
`tem compared to the parasitic losses typical of diesel fueled
`systems. For example, a conventional diesel powered fluid
`pump is rated for 2250hp. However, due to parasitic losses in
`the transmission, torque converter and cooling systems, die
`sel fueled systems typically only provide 1800 hp to the
`pumps. In contrast, the present system can deliver a true 2500
`hp directly to each pump 22 because pump 22 is directly
`coupled to electric motor 21. Further, the nominal weight of a
`conventional fluid pump is up to 120,000 lbs. In the present
`operation, each fracturing module 20 weighs approximately
`28,000 lbs., thus allowing for placement of four pumps 22 in
`the same physical dimension (size and weight) as the spacing
`needed for a single pump in conventional diesel systems, as
`well as allowing for up to 10,000 hp total to the pumps. In
`other embodiments, more or fewer fracturing modules 20
`may be located on trailer 10 as desired or required for opera
`tional purposes.
`0050. In certain illustrative embodiments, fracturing mod
`ule 20 can include a electric motor 21 that is an AC permanent
`magnet motor capable of operation in the range of up to 1500
`rpms and up to 20,000 ft/lbs of torque. Fracturing module 20
`can also include a pump 22 that is a plunger-style fluid pump
`coupled to electric motor 21. In certain illustrative embodi
`ments, fracturing module 20 can have dimensions of approxi
`mately 136" width:X108" length}x100" height. These dimen
`sions would allow fracturing module 20 to be easily portable
`and fit with a ISO intermodal container for shipping purposes
`without the need for disassembly. Standard sized ISO con
`tainer lengths are typically 20', 40' or 53'. In certain illustra
`tive embodiments, fracturing module 20 can have dimensions
`of no greater than 136" widthx108" length}x100" height.
`These dimensions for fracturing module 20 would also allow
`crew members to easily fit within the confines of fracturing
`module 20 to make repairs, as illustrated in FIG. 4b. In certain
`illustrative embodiments, fracturing module 20 can have a
`width of no greater than 102" to fall within shipping configu
`rations and road restrictions. In a specific embodiment, frac
`turing module 20 is capable of operating at 2500hp while still
`having the above specified dimensions and meeting the above
`mentioned specifications for rpms and ft/lbs of torque.
`0051
`Electric Motor
`0052. With reference to the illustrative embodiments of
`FIGS. 2 and 3, a medium low voltage AC permanent magnet
`electric motor 21 receives electric power from turbine gen
`erator 30, and is coupled directly to pump 22. In order to
`ensure suitability for use in fracturing, electric motor 21
`should be capable of operation up to 1,500 rpm with a torque
`of up to 20,000 f