Patent ID: 12228023

While the invention will be described in connection with the preferred embodiments, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF INVENTION

The method and system of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings in which embodiments are shown. The method and system of the present disclosure may be in many different forms and should not be construed as limited to the illustrated embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey its scope to those skilled in the art. Like numbers refer to like elements throughout. In an embodiment, usage of the term “about” includes +/−5% of the cited magnitude. In an embodiment, usage of the term “substantially” includes +/−5% of the cited magnitude.

It is to be further understood that the scope of the present disclosure is not limited to the exact details of construction, operation, exact materials, or embodiments shown and described, as modifications and equivalents will be apparent to one skilled in the art. In the drawings and specification, there have been disclosed illustrative embodiments and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation.

FIG.1is a schematic example of a hydraulic fracturing system10that is used for pressurizing a wellbore12to create fractures14in a subterranean formation16that surrounds the wellbore12. Included with the system10is a hydration unit18that receives fluid from a fluid source20via line22, and also selectively receives additives from an additive source24via line26. Additive source24can be separate from the hydration unit18as a stand-alone unit, or can be included as part of the same unit as the hydration unit18. The fluid, which in one example is water, is mixed inside of the hydration unit18with 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 ofFIG.1, the fluid and additive mixture is transferred to a blender unit28via line30. A proppant source32contains proppant, which is delivered to the blender unit28as represented by line34, where line34can be a conveyer. Inside the blender unit28, the proppant and fluid/additive mixture are combined to form a fracturing slurry, which is then transferred to a fracturing pump system36via line38; thus fluid in line38includes the discharge of blender unit28which is the suction (or boost) for the fracturing pump system36. Blender unit28can have an onboard chemical additive system, such as with chemical pumps and augers (not shown). Optionally, additive source24can provide chemicals to blender unit28; or a separate and standalone chemical additive system (not shown) can be provided for delivering chemicals to the blender unit28. In an example, the pressure of the slurry in line38ranges from around 80 psi to around 100 psi. The pressure of the slurry can be increased up to around 15,000 psi by pump system36. A motor39, which connects to pump system36via connection40, drives pump system36so that it can pressurize the slurry. In one example, the motor39is controlled by a variable frequency drive (“VFD”). After being discharged from pump system36, slurry is injected into a wellhead assembly41; discharge piping42connects discharge of pump system36with wellhead assembly41and provides a conduit for the slurry between the pump system36and the wellhead assembly41. In an alternative, hoses or other connections can be used to provide a conduit for the slurry between the pump system36and the wellhead assembly41. Optionally, any type of fluid can be pressurized by the fracturing pump system36to form a fracturing fluid that is then pumped into the wellbore12for fracturing the formation16, and is not limited to fluids having chemicals or proppant. Examples exist wherein the system10includes multiple pumps36, and multiple motors39for driving the multiple pumps36. Examples also exist wherein the system10includes the ability to pump down equipment, instrumentation, or other retrievable items through the slurry into the wellbore.

An example of a turbine44is provided in the example ofFIG.1and which receives a combustible fuel from a fuel source46via a feed line48. In one example, the combustible fuel is natural gas, and the fuel source46can be a container of natural gas or a well (not shown) proximate the turbine44. Combustion of the fuel in the turbine44in turn powers a generator50that produces electricity. Shaft52connects generator50to turbine44. The combination of the turbine44, generator50, and shaft52define a turbine generator53. In another example, gearing can also be used to connect the turbine44and generator50. An example of a micro-grid54is further illustrated inFIG.1, and which distributes electricity generated by the turbine generator53. Included with the micro-grid54is a transformer56for stepping down voltage of the electricity generated by the generator50to a voltage more compatible for use by electrical powered devices in the hydraulic fracturing system10. In another example, the power generated by the turbine generator and the power utilized by the electrical powered devices in the hydraulic fracturing system10are 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 generator50is conveyed to transformer56via line58. In one example, transformer56steps the voltage down from 13.8 kV to around 600 V. Other example step down voltages include 4,160 V, 480 V, or other voltages. The output or low voltage side of the transformer56connects to a power bus60, lines62,64,66,68,70, and72connect to power bus60and deliver electricity to electrically powered end users in the system10. More specifically, line62connects fluid source20to bus60, line64connects additive source24to bus60, line66connects hydration unit18to bus60, line68connects proppant source32to bus60, line70connects blender unit28to bus60, and line72connects motor39to bus60. In an example, additive source24contains ten or more chemical pumps for supplementing the existing chemical pumps on the hydration unit18and blender unit28. Chemicals from the additive source24can be delivered via lines26to either the hydration unit18and/or the blender unit28. In one embodiment, the elements of the system10are mobile and can be readily transported to a wellsite adjacent the wellbore12, such as on trailers or other platforms equipped with wheels or tracks.

Schematically illustrated inFIG.2is one example of a fracturing pump system36A having pumps80,82that are respectively powered by motors84,86. Couplings88,90mechanically affix the pumps80,82with motors84,86so that when motors84,86are energized, the motors84,86will drive pumps80,82for pressurizing fracturing fluid that is then delivered to the wellbore12(FIG.1). In this example, the fracturing pump system36A is mounted on a trailer92which provides a mobile surface for transporting components of the fracturing pump system36A to and from designated locations. Thus when operations at a wellsite are deemed complete, the fracturing pump system36A can be transported to another wellsite for subsequent operations, or to a facility for repair or maintenance. Also schematically represented on trailer92and as part of the fracturing pump system36A, are a motor control center94and auxiliary components96. Examples of auxiliaries include heaters for the motors84,86, lights on the fracturing pump system36A, control power for a variable frequency drive (not shown), heater for lube oil for pumps80,82, air blowers (not shown) for motors84,86, a hydraulic pump motor, and a hydraulic cooler motor (not shown). Not shown are variable frequency drives to control and operate motors84,86. In another embodiment, a single variable frequency drive controls and operates a single motor84which turns one or more hydraulic fracturing pumps (80and82).

Also shown inFIG.2is an example of transformer56A having a high voltage side HV connected to line58A; junction boxes98,100respectively mounted on transformer56A and fracturing pump system36A provide means for electrical communication between transformer56A and fracturing pump system36A. Junction box98is mounted on a low voltage side LV of the transformer56A As will be described in more detail below, junction boxes98,100are equipped with quick disconnect receptacles so that lines having conductive wires and that conduct electricity between transformer56A and fracturing pump system36A, can be easily inserted and removed by operations personnel to significantly reduce the time required for assembly and disassembly of the hydraulic fracturing system10. The electrically conducting lines between junction boxes98,100include wire bundles102,104, which as will be described below each include a number of wires within and that are separable and distinct from one another. Wire bundles102,104conduct electrical power from transformer56A and to junction box100and which is used for energizing motors84,86. Also extending between junction boxes98,100is line106and which conducts electricity that is used for powering the motor control center94and auxiliary components96. Also extending between junction boxes98,100is line108which is used as a ground between the transformer56A and the hydraulic fracturing pump unit36A. In one embodiment, the power generated is of the same voltage as the power supplied to the hydraulic fracturing pump unit36. In this case, power for the hydraulic fracturing pump unit36is supplied directly without needing a transformer56.

FIG.3shows an end perspective view of an example of junction box98and having a row110of receptacles1121-1126. The receptacles1121-1126are each equipped with an opening1141-1146in which an electrical conducting plug can be readily inserted and removed thereby providing electrical communication between the plug and attached conducting lead (such as a cable). Set below and extending generally parallel with row110is row116which also includes receptacles1181-1186, wherein the receptacles1181-1186are each equipped with openings1201-1206for receiving an electrically conducting plug. Set adjacent receptacle1126is a ground connection122which connects to ground leads within transformer56A (FIG.2). Below ground connection122is an auxiliary/MCC connection124, which provides a source of electrical power for the auxiliary components96and motor control center94(FIG.2). In another embodiment, the receptacles can be arranged in different patterns and configurations.

FIG.4shows an end perspective view of one example of junction box100which includes a row126of receptacles1281-1286, wherein the receptacles each have an opening1301-1306on their ends distal from where they mount to junction box100. Parallel with and set below row126is row132, which is made up of a line of receptacles1341-1346each having openings1361-1366. Also included with junction box100is a ground connection138and an auxiliary/MCC connection140. In another embodiment, the receptacles can be arranged in different patterns and configurations.

FIG.5shows in a side perspective view one example of a cable assembly142which includes plugs144,146and a cable148extending between the plugs144,146which provides electrical communication between plugs144,146. Plugs144,146as shown each have an outer periphery configured so that plugs144,146can be readily inserted into and removed from openings1141-1146,1201-1206,1301-1306,1361-1366. Optionally included with the plugs144,146are electrodes149which are electrically conductive elements. Electrodes149are shown formed along the outer curved surface of plugs144,146and can be recessed or inlayed on the surface of the plugs144,146or can project radially outward. Alternate examples of electrodes149A resemble planar prongs that project axially outward from the respective ends of plugs144,146opposite from their connection to cable148. When the plugs144,146are inserted into a one of the receptacles1121-1126,1181-1186,1281-1286,1341-1346ofFIG.3or4, the electrodes149,149A come into electrically conducting contact with corresponding electrodes (not shown) provided within the receptacles1121-1126,1181-1186,1281-1286,1341-1346; and thereby providing electrical communication one of the receptacles1121-1126,1181-1188disposed injunction box98and one of the receptacles1281-1286,1341-1346disposed injunction box100.

Referring back toFIG.2, line150is shown within fracturing pump system36A and extending from a side of junction box100opposite from cable bundle102and connecting to motor86. Accordingly, electrical communication between transformer56and motor86takes place from junction box98, through cable bundle102, to junction box100, then to line150. Although shown as a single line, line150can be made up of a plurality of electrically conducting elements such as lines or cables and may include a variable frequency drive. One specific example of forming cable bundle102, six of the cable assemblies142are provided, and one of plugs144,146are inserted into each of the openings1141-1146of receptacles1121-1126. The other one of the plugs144,146of cable assemblies142is then inserted into a corresponding opening1301-1306of receptacles1281-1286. Thus in one example the six cable assemblies142extending between the receptacles1121-1126to receptacles1281-1286define cable bundle102for powering motor86. An advantage of the cable assemblies142with insertable and removable plugs144,146and receptacles1121-1126and receptables1281-1286is that the electrical communication between transformer56A and motor86can be assembled in a matter of minutes, versus the hours that has typically been required for hardwiring the electrical connection between the transformer56A and motor86. Similarly, cable bundle104is formed by providing six of the cable assemblies142and connecting them with the plugs144,146into the receptacles1181-1186and receptacles1341-1346. In similar fashion, a ground connection108between transformer56A and fracturing pump system36A is created by providing cable assembly142and inserting one of plugs144,146into ground connection122and the other one of the plugs144,146into ground connection138. Optionally, simple bolt on lug attachments (not shown) can be used in lieu of the cable assemblies142for the ground connections122,138. Thus, while cable bundles102,104each include six or more of the cable assemblies142, example lines106,108can include a single cable assembly142. Alternatively, line106is made up of four internal conductors and have threaded end connections instead of the plugs. Optionally, cable bundles102,104can be made up of less than six cable assemblies142, or more than six cable assemblies142.

In the example ofFIG.2power to motors84,86from transformer56A is provided along separate and distinctive paths. A separate VFD may control and operate motor84while a second VFD controls and operates motor86. An advantage of the separate and distinct paths of providing power to motors84,86is that should power to one of motors84,86be interrupted, power to the other one of the motors84,86is not affected. More specifically, adjacent rows110,116are not in communication with one another, adjacent rows126,132are not in communication with one another; and adjacent cable bundles102,104are not in communication with one another. Finally, lines150,152are also separate and insulated from each other so that independent electrical paths are maintained for both the motors84,86. An additional advantage is provided by the dedicated ground line which plugs into ground connections122,138. The dedicated ground line may reduce voltage differential between equipment. In another embodiment, one VFD controls and operates one motor (either84or86), which then controls both pump80and pump82.

FIG.6shows in a side perspective view one example of a fracturing pump system36B mounted on trailer92B. In this example, an end of trailer92B distal from pumps80B,82B includes an enclosure160and inside of which is an example of a variable frequency drive162shown in a dashed outline. Adjacent variable frequency drive162a panel164is formed on enclosure160, where panel164is readily removable from enclosure to give ready and full access to variable frequency drive162. Panel164thus provides a way of quick and easy access for the repair, replacement, and/or maintenance of variable frequency drive162. Also provided on enclosure160is a door166which allows access by operations personnel to inside of enclosure160to access and monitor various controls provided within enclosure160. In one embodiment, the enclosure160includes two air conditioning units. Having two air conditioning units provides redundant cooling systems. Each air conditioning unit is capable of cooling both VFDs in the enclosure by itself should the other fail or need to be shut down for repair and maintenance.

FIG.7shows an end perspective view of one example of enclosure160, and wherein rows126,132are provided in a recess168formed within junction box100. Included in this example is an optional electric filter201A in communication with the first VFD and motor84and a second electric filter201B in communication with the second VFD and motor86. Optionally, a second variable frequency drive (not shown) is provided within enclosure160and on a side opposite panel164; a second panel (not shown) can be formed on enclosure to facilitate access to second variable frequency drive. In this example, each motor80B,82B is coupled with a dedicated variable frequency drive. In one embodiment, there is a second door for the enclosure providing a second, separate and distinct escape path from the enclosure. In one embodiment, the exit doors open outwards to allow for quick egress from the enclosure160.

Referring back toFIGS.3and4, the arrangement of the receptacles1121-1126,1181-1186,1281-1286,1341-1346on junction boxes98,100are generally mirror images of one another. Thus, when inserting one of plugs144,146into receptacle1121, the corresponding receptacle, which is 1281, will be aligned so that the cable assembly142can run along a generally straight path between junction boxes98,100and without interfering with other cable assemblies142that connect into other receptacles. Moreover, in the illustrated example motors84,86operate on three phase electricity, thus, in an alternative, the adjacent ones of receptacles transmit electricity that is at the same phase. For example, receptacles1121-1122may transmit electricity at one phase, whereas receptacles1123,1124transmit electricity at a different phase, and receptacles1125,1126transmit electricity at yet another phase, wherein these different phases are approximately 120° apart. Further in this example, receptacles1281,1282operate at one phase, wherein receptacles1283,1284operate at another phase, and receptacles1285,1286operate at a third phase. In one specific example, receptacles1121,1122operate at the same phase as receptacles1281,1282, receptacles1123,1124operated at the same phase as receptacles1283,1284, and receptacles1125,1126operate at the same phase as receptacles1285,1286. By strategically forming a cable bundle102,104made up of wires having dedicated phases, and allocating the same phase of electricity to cross more than one wire, a gauge of wire for the cable assemblies142can be formed which is manageable by operations personnel, which is another advantage of the present disclosure and which speeds the assembly and disassembly of the fracturing system10.

FIG.8shows an end perspective view of an example of transformer56B having recesses170,172and with its sets of receptacles112B1-112B6and118B1-118B6each arranged in a pair of rows respectively in the recesses170,172. As shown, receptacles112B1-112B6are arranged so that receptacles112B1and112B4are vertically aligned with one another, receptacles112B2and112B5are vertically aligned with one another, and receptacles112B3and112B6are vertically aligned with one another. In this example, receptacles112B1and112B4are in communication with electricity at a first phase, receptacles112B2and112B5are in communication with electricity at a second phase, and receptacles112B3and112B6are in communication with electricity at a third phase; where the first, second, and third phases are different, and can be about 120° apart from one another. Further illustrated are that receptacles118B1-118B6in recess172are arranged so that receptacles118B1and118B4are vertically aligned with one another, receptacles118B2and118B5are vertically aligned with one another, and receptacles118B3and118B6are vertically aligned with one another. In this example, receptacles118B; and118B; are in communication with electricity at a first phase, receptacles118B2and118B5are in communication with electricity at a second phase, and receptacles118B3and118B6are in communication with electricity at a third phase; where the first, second, and third phases are different, and can be about 120° apart from one another. Additionally, ground connection122B and auxiliary connection124B are shown disposed in recess172.

The present invention described herein, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While a presently preferred embodiment of the invention has been given for purposes of disclosure, numerous changes exist in the details of procedures for accomplishing the desired results. For example, other the recesses can be put into arrangements other than those described, such as all being in a vertical or other arrangement. These and other similar modifications will readily suggest themselves to those skilled in the art, and are intended to be encompassed within the spirit of the present invention disclosed herein and the scope of the appended claims.