Hydraulic Fracturing Spread and Mechanisms

This application is a divisional of U.S. Non-Provisional application Ser. No. 18/470,215, filed Sep. 19, 2023, which was a continuation of U.S. application Ser. No. 17/762,882 filed on Mar. 23, 2022, now U.S. Pat. No. 11,761,318, issued Sep. 19, 2023, which was a U.S. National Stage Application of PCT/US21/14004 filed on Jan. 19, 2021, which claimed the benefit of U.S. Provisional Application Ser. No. 62/962,007, filed on Jan. 16, 2020, all of which are incorporated herein by reference.

The present disclosure relates to hydraulic fracturing. More particularly, the present disclosure relates to a hydraulic fracturing spread and method.

Hydraulic fracturing has been used for years to extract oil and gas from shale reservoirs far below the earth's surface. To release the oil and gas in the reservoirs, a hole is drilled straight down into the earth. A casing is then placed within the hole and cement is introduced to secure the casing in place. After the casing is secure, horizontal drilling follows and another casing is placed into the horizontal section, which allows a perforating gun to enter and puncture holes in the casing. These holes are then ready to receive fracturing fluid pumped at high pressure, causing the fractures that will release oil and/or gas. This process is a form of well stimulation referred to as hydraulic fracturing. There are many possible constituents of fracturing fluid used in various fracturing treatments, but the most common is primarily water mixed with sand and various chemicals. Pressures in excess of 15,000 psi may be required, depending on the specific well geology and the fracturing treatment.

A pressure pumping arrangement for stimulating an oil well typically involves individual pumping units on truck trailers, which pump fracturing fluid for hydraulic fracturing. Flow from each individual truck is collected into a manifold and directed to a wellhead (this system is typically referred to as a “spread”). A typical fracturing treatment may require the flow of fracturing fluid from twelve trucks, each with 3000 horsepower engines pumping the fluid directly with crank-driven plunger pumps. High pressure connections are required between each pump and the manifold. These connections often present safety concerns and require expensive maintenance and replacement due to wear. With as many as twelve trucks, and often more, in a spread, there are many high-pressure connections that have to be continually checked and maintained to avoid accidents. Additionally, spreads usually require a large footprint to operate, which requires preparing a large pad around a well site.

Accordingly, there is a need for a hydraulic fracturing spread that can decrease the length of high-pressure lines and decrease the number of high-pressure connections, while decreasing the typical footprint of the spread. The present disclosure seeks to solve these and other problems.

In one embodiment, a hydraulic fracturing spread comprises a hydraulic oil tank unit which supplies hydraulic oil at low pressures to manifold assemblies. The hydraulic oil, at low pressure, is sent to low pressure oil-hydraulic manifolds within one or more manifold assemblies. The hydraulic oil is then sent from the oil-hydraulic manifolds to oil-hydraulic pumper units, which increase the pressure of the hydraulic oil and pump the hydraulic oil, now at medium pressure, to intensifier units and valving, each of which are positioned in the manifold assemblies. A fracturing fluid source (e.g., a blender) sends fracturing fluid through low pressure fracturing fluid manifolds to the intensifier pump units, where the pressure of the fracturing fluid is increased to the desired pressure or PSI (e.g., high pressure). The intensifier pumps may be double-acting intensifier pumps or single-acting intensifier pumps. The high-pressure fracturing fluid is then sent to high-pressure fracturing fluid manifolds positioned on the manifold assemblies. The high-pressure fracturing fluid is delivered to a well bore to initiate the fracturing process.

In one embodiment, the oil-hydraulic pumper units comprise diesel-powered pumps. In another embodiment, the oil-hydraulic pumper units comprise electric motors to drive the oil-hydraulic pumps. In another embodiment the oil hydraulic pumper units comprise turbines to drive the oil-hydraulic pumps.

The following descriptions depict only example embodiments and are not to be considered limiting in scope. Any reference herein to “the invention” is not intended to restrict or limit the invention to exact features or steps of any one or more of the exemplary embodiments disclosed in the present specification. References to “one embodiment,” “an embodiment,” “various embodiments,” and the like, may indicate that the embodiment(s) so described may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Further, repeated use of the phrase “in one embodiment,” or “in an embodiment,” do not necessarily refer to the same embodiment, although they may.

Reference to the drawings is done throughout the disclosure using various numbers. The numbers used are for the convenience of the drafter only and the absence of numbers in an apparent sequence should not be considered limiting and does not imply that additional parts of that particular embodiment exist. Numbering patterns from one embodiment to the other need not imply that each embodiment has similar parts, although it may.

Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalents thereof. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Unless otherwise expressly defined herein, such terms are intended to be given their broad, ordinary, and customary meaning not inconsistent with that applicable in the relevant industry and without restriction to any specific embodiment hereinafter described. As used herein, the article “a” is intended to include one or more items. When used herein to join a list of items, the term “or” denotes at least one of the items, but does not exclude a plurality of items of the list. For exemplary methods or processes, the sequence and/or arrangement of steps described herein are illustrative and not restrictive.

It should be understood that the steps of any such processes or methods are not limited to being carried out in any particular sequence, arrangement, or with any particular graphics or interface. Indeed, the steps of the disclosed processes or methods generally may be carried out in various sequences and arrangements while still falling within the scope of the present invention.

The term “coupled” may mean that two or more elements are in direct physical contact. However, “coupled” may also mean that two or more elements are not in direct contact with each other, but yet still cooperate or interact with each other.

The terms “comprising,” “including,” “having,” and the like, as used with respect to embodiments, are synonymous, and are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including, but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes, but is not limited to,” etc.).

As previously discussed, there is a need for a hydraulic fracturing spread that can decrease the number of pressure pumps, decrease the number of high-pressure connections, and that decreases the typical hydraulic fracturing spread footprint. As will be appreciated, the hydraulic fracturing spread disclosed herein solves these problems and others.

A pressure pumping arrangement for stimulating an oil well typically has individual pumping units on truck trailers, which pump fracturing fluid for hydraulic fracturing. Pressures in excess of 15,000 psi may be required, depending on the specific well geology and the fracturing treatment. Flow from each pumping unit is collected in a manifold and directed to the wellhead. The fracturing treatment may require flow of oil from numerous trucks (e.g.,trucks), each having their own pumping unit. High pressure connections are required between each pump and the manifold. These high-pressure lines present safety concerns and require expensive maintenance. This typical spread also requires a large footprint due to the many trucks with pumps and the trucks for transport.

Generally, a hydraulic fracturing spread system described herein comprises manifold assemblies with pressure intensifier pumps. Oil-hydraulic pumps may be coupled separately from a pressure intensifier, where hydraulic oil at medium pressure (e.g., 6000 PSI) drives a piston which pumps the fracturing fluid via a smaller diameter plunger piston. In the pressure intensifier units, the difference of the pressure-affected area of the oil hydraulic piston and the fluid pumping plunger represents an intensification ratio (e.g., 3:1) which, in turn, provides an increase in pressure of the fracturing fluid pumped by the plunger (e.g., 18,000 PSI). It will be appreciated that, due to the aid of the pressure intensifier units, integrated into manifold assemblies which collect and transport the high-pressure fracturing fluid toward the well bore, less length of high-pressure lines is required and fewer high-pressure connections are made on the well site, thereby decreasing safety concerns, increasing efficiency due to less downtime for maintenance. Furthermore, consolidating more horsepower on each oil-hydraulic pumping unit may reduce the number of transportation units and decrease the footprint size required for the spread. Additionally, the manifold assemblies allow a user to easily transport a whole hydraulic fracturing spread from site to site.

Referring to the diagram illustrated in, in one embodiment, a hydraulic fracturing spread systemcomprises a hydraulic oil tank unit(hydraulic oil source) which supplies hydraulic oil at first, low pressures to manifold assembliesA-C, which are coupled together. More specifically, hydraulic oil at low pressure is sent, for example, via low pressure oil lines (shown as lines A) to low pressure oil-hydraulic manifoldsA-C within each of the manifold assembliesA-C. The hydraulic oil is then sent from the oil-hydraulic manifoldsA-C at low pressure (lines A) to oil-hydraulic pumper unitsA-C, which increase the pressure of the hydraulic oil. It will be appreciated that the low pressure oil-hydraulic manifoldsA-C are interposed between the hydraulic oil tank unitand the one or more oil-hydraulic pumper unitsA-C. The hydraulic oil is then pumped at a second, medium pressure flow (shown as lines B) to intensifier units and valvingA-C, each of which are positioned in the manifold assembliesA-C. This is a distinction from the prior art, which requires high-pressure connections from the oil-hydraulic intensifiers and the pumper units. By removing these high-pressure connections, safety is increased, downtime and maintenance is reduced, among other things, which is a considerable improvement over the prior art.

A fracturing fluid source(e.g., a blender) sends fracturing fluid through first, low pressure (lines C) to first fracturing fluid manifoldsA-C (low pressure manifolds) within the manifold assembliesA-C. These low-pressure manifoldsA-C send the fracturing fluid at low pressure (lines C) to the intensifier pump units and valvingA-C, where the pressure for the fracturing fluid is increased to the desired PSI. It will be appreciated that the low-pressure manifoldsA-C may be interposed between the fracturing fluid sourceand the intensifier pump units and valvingA-C. It further will be appreciated that the intensifier pump units and valvingA-C use clean oil-hydraulic pressure to drive and increase the pressure of the fracturing fluid to a second, high pressure fracturing fluid. In some embodiments, as later described, the intensifier pump units and valvingA-C may be double-acting intensifier pumps or single-acting intensifier pumps.

The second, high-pressure fracturing fluid is then sent to second fracturing fluid manifoldsA-C (high-pressure manifolds), positioned on the manifold assembliesA-C, via high pressure flow lines (lines D) from the intensifier pump unitsA-C. The high-pressure flow (lines D) of fracturing fluid is then sent to a well boreto initiate the fracturing process. In some embodiments, the high-pressure flow (lines D) is transported through a large diameter pressure trunk line (shown in).

Accordingly, the high-pressure fracturing fluid is sent from one manifold assembly to the next via the high-pressure trunk line(). In some embodiments, the trunk lines couple the manifold assembliesA-C to each other. While three manifold assembliesA-C are shown, it will be appreciated that one or more assemblies may be used in the hydraulic fracturing spread system. The term “well bore” as used to describeis a generalization of the connection to the formation for fracturing. It will be appreciated there are multiple components after the manifold (or “missile”) in a typical fracturing spread. For example, instrumentation, valves, a “zipper” manifold which connects to multiple well heads, the well heads themselves, tubing and casing may be part of the connection to the wellbore.

Additionally, each of the manifold assembliesA-C as illustrated incomprise low pressure oil-hydraulic manifoldsA-B, intensifier pump units and valvingA-C, low-pressure fracturing fluid manifoldsA-C, and high-pressure fracturing fluid manifoldsA-C. However, it will be understood that numerous configurations of the manifold assemblies may be envisioned. For example, one manifold assembly may comprise a generator, a hydraulic oil tank, and a portion of trunk line while another manifold assembly may comprise a dual-action intensifier pump, oil-hydraulic pumper units, and a portion of the trunk line, with the rest of the manifold assemblies being configured as shown in. The various manifold assembly configurations may then be coupled together, via the trunk line (e.g.,in), to create a hydraulic fracturing spread system.

As shown in, the oil-hydraulic pumper unitsmay be mounted separately from the manifold assemblies(which comprise the intensifier units and valving(shown in)). In the oil-hydraulic pumper units, hydraulic oil at medium pressure (e.g., 6000 PSI) drives a pistonwhich pumps fracturing fluid via a plunger piston (e.g., smaller diameter). The pumper unitscomprise a pump actuator(e.g., engine, motor, turbine, etc.) that drives a pumpof the oil-hydraulic pumper units. The pump actuatormay be coupled with the oil-hydraulic pumpson a truck trailer, skid, or any other location. In one embodiment, multiple pump actuatorsmay be coupled to a truck trailer. Thus, the same amount of hydraulic horsepower can be condensed to a smaller footprint (e.g., 4 truck trailer units instead of 12). The example oil-hydraulic pumper unitsshown inare illustrated as large piston engines (the pump actuator) with a plurality of hydraulic pumpsattached to each engine via a geared transfer case. However, it will be appreciated that one or more pump actuators each driving one or multiple pumps can be unitized for a specific application. Oil-hydraulic pumper unitsrefer to a system which increases the pressure of the hydraulic oil and pumps the hydraulic oil at medium pressure.

While the truck-mounted example is shown and described above, it will be appreciated that, in some embodiments, the oil-hydraulic pumping unitscomprising one or more pump actuatorsmay be mounted to skids and stacked or coupled together with other oil-hydraulic pumping units, and/or with the intensifier pumps. Each pump actuatormay have multiple oil-hydraulic pumpsdriven by a gear train (as shown), or one large oil-hydraulic pump may be driven by the pump actuators. In some embodiments, the oil-hydraulic pumpsare each individually driven by a separate pump actuator, such as a motor, engine, turbine, etc. In some embodiments, the pump actuatorsare internal combustion engines (e.g., diesel or natural gas) or turbine engines. In some embodiments, the pump actuatorsmay be electric motors. The electric motors may be used to drive the oil-hydraulic pumpson the pumper units. In some embodiments, a large, central generator (e.g., diesel or turbine) may produce power to drive a plurality of the electric motors (i.e., pump actuators) of the oil-hydraulic pumper units. Alternatively, turbine or piston engines can be used to power the oil-hydraulic pumps, or any other suitable mechanism or prime mover.

Intensifier units and valvingmay be driven by the oil-hydraulic pumper units, or flow from multiple oil-hydraulic pumps may be consolidated to drive individual intensifiers. In particular, the intensifier units may be driven by hydraulic oil sent through oil-hydraulic lines and connections(e.g., medium pressure lines). It will be appreciated that using medium pressure lines, and fewer of them than is commonly used on spreads, that connect the oil hydraulic pumpsto the pressure intensifier pumpsdecreases maintenance and decreases the likelihood of accident. In contrast, systems in the prior art use many high-pressure fracturing fluid connections and lines that have to be maintained to avoid accidents. In some embodiments, a double intensifier pump may be used, such as the pump disclosed in U.S. Pat. No. 5,879,137, issued on Mar. 9, 1999, which is incorporated herein by reference. The intensifier pump shown in the prior art is double-acting, where fluid is pumped in both directions of the hydraulic piston's travel. The hydraulic spread systemmay comprise a single- or double-acting intensifier pump as shown in the prior art. In some embodiments, the oil-hydraulic pumper unitsand the intensifier units and valvingmay be mounted together, forming a single unit in the manifold assemblies.

However, it will also be appreciated that the intensifier units and the valving (e.g., control valves) may be separated from one another. For example, the valving may be located on the oil-hydraulic pumper unit or in any other location that allows for functionality of the valves.

In one embodiment, electronically controlled pumps could be implemented to control flow. Additionally, control valves for oil-hydraulic pumper unitsmay be on the pumping unitsand/or the intensifier units. The hydraulic oil tank unitand cooling may be on each of the truck bedsor separate from the oil-hydraulic pumper units. For example, one large tank and cooling system can be on a separate truck trailer or skid and shared between multiple hydraulic pump units. Accordingly, a large tank can service a plurality of oil-hydraulic pumper units. Further, in some embodiments, the manifold assembliesmay distribute hydraulic oil flows between themselves (as shown in). For example, low pressure fluid could flow (along lines A) from a large central tanknear the blender unit, through a series of connections (lines A) between manifold assembliesto supply oil-hydraulic pumper units. Exhausted low pressure hydraulic oil leaving intensifiersand control valves can then return through a series of connections (lines A) between manifold assembliesback to the central tank.

As previously discussed, fracturing fluid from the fracturing fluid source() feeds the pressure intensifier manifoldsand the intensifier pumpsat relatively low pressure via a low-pressure intake line(). High-pressure fracturing fluid is then pumped to a wellheadvia a high-pressure output lineat a higher pressure due to the intensifier pumps. Referring to, the high-pressure fracturing fluid can be moved through high pressure fracturing fluid linesto a trunk linecoupled to each of the manifold assemblies. Additionally,show manifold assembliescoupled horizontally to each other via the trunk lines. In particular, the trunk linesmay comprise a joint, which allows each trunk line section on each manifold assemblyto be coupled to each other. The jointmay be a flange with a seal that receives bolts, or any other type of coupler. Furthermore,show manifold assembliescoupled and stacked vertically with the high-pressure fracturing fluid linesconnecting the bottom manifold assemblies to the top manifold assemblies through the intensifier pumpsto consolidate the flow from the bottom and top manifolds into the trunk line. Accordingly, the trunk lineruns through each manifold assembly. Thus, the oil-hydraulic pumper unitsmay be adjacent to each manifold assembly. When multiple manifold assembliesare coupled together, the length of the trunk lineincreases as well as the number of intensifier units and valving. It will be appreciated that having manifold assembliescomprising trunk linesto move the fracturing fluid and intensifier units and valvingto increase the pressure of the fluid creates a smaller, easier to maintain layout. Additionally, the manifold assembliesare easily transported and connected with fewer connections than hydraulic fracturing layouts in the prior art, which increases efficiency, decreases energy loss, and decreases the number of high-pressure lines. In some embodiments, the manifold assembliesmay comprise a frame/skid, allowing the manifold assembliesto be placed directly on the ground. However, it will also be appreciated that components of hydraulic fracturing spreads are commonly transported and used as skids, integrated with a vehicle or as a vehicle trailer assembly. All parts of this system can have any of those options as well for the specific application, or any other means of transporting and placing into service.

To supply the pressure and flow requirements for a particular pumping treatment, multiple manifold assemblieswith multiple intensifier pump unitsmay be used. As shown in, the manifold assembliesmay be coupled horizontally. As shown in, in one embodiment, the manifold assembliesmay be stacked vertically. Additionally, in some embodiments, the hydraulic spread systemmay comprise a combination of both vertically stacked manifold assembliesand horizontally coupled manifold assemblies. It will be appreciated that any other configuration of the manifold assembliesis within the parameters of the hydraulic spread system. The manifold assemblies, whether in a vertical or horizontal coupling position, may couple to each other with alignment hardware, such as tapered alignment pins on the skid, which may allow for ease of attaching the fluid connections between manifold assemblies. For example, API flange connections between manifold assembliesmay allow few large diameter connections rather than multiple small diameter connections with swivel joints.

The hydraulic fracturing spread systemmay condense the footprint further than is possible for truck-mounted units. For example, the systemallows multiple manifold assemblies to be stacked. With off-shore applications, for example, footprint must be minimized and ease of loading and unloading equipment by crane is needed. Accordingly, the systemdecreases footprint size for both land and off-shore applications. Not only is the footprint reduced but the number of connections and lengths required to get the hydraulic fracturing fluid to the high-pressure pumps and to the well bore is reduced. While oil-based fluids were used as examples throughout, the present disclosure is not so limited, and other pressurizable fluids (e.g., water, water and glycol, etc.) may be used without departing herefrom.

It will also be appreciated that systems and methods according to certain embodiments of the present disclosure may include, incorporate, or otherwise comprise properties or features (e.g., components, members, elements, parts, and/or portions) described in other embodiments. Accordingly, the various features of certain embodiments can be compatible with, combined with, included in, and/or incorporated into other embodiments of the present disclosure. Thus, disclosure of certain features relative to a specific embodiment of the present disclosure should not be construed as limiting application or inclusion of said features to the specific embodiment unless so stated. Rather, it will be appreciated that other embodiments can also include said features, members, elements, parts, and/or portions without necessarily departing from the scope of the present disclosure.

Moreover, unless a feature is described as requiring another feature in combination therewith, any feature herein may be combined with any other feature of a same or different embodiment disclosed herein. Furthermore, various well-known aspects of illustrative systems, methods, apparatus, and the like are not described herein in particular detail in order to avoid obscuring aspects of the example embodiments. Such aspects are, however, also contemplated herein.

Exemplary embodiments are described above. No element, act, or instruction used in this description should be construed as important, necessary, critical, or essential unless explicitly described as such. Although only a few of the exemplary embodiments have been described in detail herein, those skilled in the art will readily appreciate that many modifications are possible in these exemplary embodiments without materially departing from the novel teachings and advantages herein. Accordingly, all such modifications are intended to be included within the scope of this invention.