Hydraulic fracturing system, apparatus, and method
11149514 · 2021-10-19
Assignee
Inventors
- Brian C. Witkowski (Fort Worth, TX, US)
- Nadiya Fuller (Plano, TX, US)
- Nuder Said (Fort Worth, TX, US)
- Duc Thanh Tran (Spring, TX, US)
- Peter Walter (Fort Worth, TX, US)
Cpc classification
F16K5/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F04B23/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B01F2101/49
PERFORMING OPERATIONS; TRANSPORTING
E21B33/068
FIXED CONSTRUCTIONS
F16L41/03
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16K11/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16K5/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F04B47/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16K11/048
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
E21B43/2607
FIXED CONSTRUCTIONS
F04B15/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16K31/126
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
E21B33/068
FIXED CONSTRUCTIONS
F04B23/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F04B15/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F04B47/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
E21B33/038
FIXED CONSTRUCTIONS
F16K11/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16K5/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16K5/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16L41/03
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F04B23/06
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16K31/126
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
An apparatus according to which a subterranean formation in which a wellbore extends is hydraulically fractured, the apparatus comprising first and second manifolds, the first manifold including first and second flow lines adapted to be in fluid communication with first and second pumps, respectively, the first pump being adapted to pressurize fluid received from the first flow line, and the second pump being adapted to pressurize fluid received from the second flow line, and the second manifold including a third flow line adapted to convey pressurized fluid from the first and second pumps to the wellbore to hydraulically fracture the subterranean formation in which the wellbore extends. The apparatus is adapted to be connected to another apparatus used to hydraulically fracture the subterranean formation in which the wellbore extends by moving one, or both, of the first and second flow lines relative to the third flow line.
Claims
1. A system used to hydraulically fracture a subterranean formation in which a wellbore extends, the system comprising: a first manifold adapted to be in fluid communication with first and second pumps, the first and second pumps being adapted to pressurize fluid received from the first manifold; a second manifold adapted to receive pressurized fluid from the first and second pumps; a first skid to which the first and second manifolds are mounted; a third manifold adapted to be in fluid communication with third and fourth pumps, the third and fourth pumps being adapted to pressurize fluid received from the third manifold; a fourth manifold adapted to receive pressurized fluid from the third and fourth pumps; a second skid to which the third and fourth manifolds are mounted, wherein the first manifold is adapted to be connected to, and in fluid communication with, the third manifold; and wherein, while the first and second manifolds are mounted to the first skid and the third and fourth manifolds are mounted to the second skid, one, or both, of the first and third manifolds are movable, relative to the second and fourth manifolds, respectively, to permit the connection of the first manifold to the third manifold.
2. The system of claim 1, wherein the second manifold is adapted to be connected to, and in fluid communication with, the fourth manifold to convey the pressurized fluid from the first, second, third, and fourth pumps to the wellbore to hydraulically fracture the subterranean formation in which the wellbore extends.
3. The system of claim 1, wherein: the first manifold comprises first and second flow lines adapted to be in fluid communication with the first and second pumps, respectively; the third manifold comprises third and fourth flow lines adapted to be in fluid communication with the third and fourth pumps, respectively; and the third and fourth flow lines are adapted to be connected to, and in fluid communication with, the first and second flow lines, respectively.
4. The system of claim 3, wherein: one, or both, of the first and third flow lines are movable relative to the second and fourth manifolds, respectively, to permit the connection of the third flow line to the first flow line; and one, or both, of the second and fourth flow lines are movable relative to the second and fourth manifolds, respectively, to permit the connection of the fourth flow line to the second flow line.
5. The system of claim 4, wherein the first skid comprises first and second rails; wherein the second skid comprises third and fourth rails; and wherein the system further comprises first, second, third, and fourth trucks to which the first, second, third, and fourth flow lines, respectively, are connected; wherein one, or both, of the first and third trucks are movable along the first and third rails, respectively, to thereby permit the movement of one, or both, of the first and third flow lines relative to the second and fourth manifolds, respectively; and wherein one, or both, of the second and fourth trucks are movable along the second and fourth rails, respectively, to thereby permit the movement of one, or both, of the second and fourth flow lines relative to the second and fourth manifolds, respectively.
6. The system of claim 3, wherein: the second manifold comprises a fifth flow line, the second manifold being supported in an elevated position above the first manifold so that the fifth flow line is vertically offset from the first and second flow lines; and the fourth manifold comprises a sixth flow line, the fourth manifold being supported in an elevated position above the third manifold so that the sixth flow line is vertically offset from the third and fourth flow lines.
7. The system of claim 6, wherein: the first, second, and fifth flow lines define first second and third inner diameters, respectively, the third inner diameter being greater than the first and second inner diameters; and the third, fourth, and sixth flow lines define fourth, fifth, and sixth inner diameters, respectively, the sixth inner diameter being greater than the fourth and fifth inner diameters.
8. The system of claim 1, further comprising a zipper manifold adapted to convey the pressurized fluid from the second manifold to the wellbore and at least one other wellbore extending in the subterranean formation to hydraulically fracture the subterranean formation in which the wellbore and the at least one other wellbore extend.
9. A method of hydraulically fracturing a subterranean formation in which a wellbore extends, the method comprising: providing first and second manifolds, the first manifold being adapted to be in fluid communication with first and second pumps, the first and second pumps being adapted to pressurize fluid received from the first manifold, and the second manifold being adapted to receive pressurized fluid from the first and second pumps; mounting the first and second manifolds to a first skid; providing third and fourth manifolds adjacent the first and second manifolds, respectively, the third manifold being adapted to be in fluid communication with third and fourth pumps, the third and fourth pumps being adapted to pressurize fluid received from the third manifold, and the fourth manifold being adapted to receive pressurized fluid from the third and fourth pumps; mounting the third and fourth manifolds to a second skid; connecting the fourth manifold to the second manifold; connecting the first manifold to the third manifold by moving one, or both, of the first and third manifolds relative to the connected second and fourth manifolds, respectively, while the first and second manifolds are mounted to the first skid and the third and fourth manifolds are mounted to the second skid; and communicating pressurized fluid from the first, second, third, and fourth pumps to the wellbore via the second and fourth manifolds to hydraulically fracture the subterranean formation in which the wellbore extends.
10. The method of claim 9, wherein: the first manifold comprises first and second flow lines adapted to be in fluid communication with the first and second pumps, respectively; and the third manifold comprises third and fourth flow lines adapted to be in fluid communication with the third and fourth pumps, respectively.
11. The method of claim 10, wherein: connecting the first manifold to the third manifold further comprises connecting: the third flow line to the first flow line; and the fourth flow line to the second flow line; and moving one, or both, of the first and third manifolds relative to the second and fourth manifolds, respectively, comprises moving: one, or both, of the first and third flow lines relative to the second and fourth manifolds, respectively; and one, or both, of the second and fourth flow lines relative to the second and fourth manifolds, respectively.
12. The method of claim 10, wherein the first skid comprises first and second rails; and wherein the second skid comprises third and fourth rails.
13. The method of claim 12, further comprising connecting the first, second, third, and fourth flow lines to first, second, third, and fourth trucks, respectively; wherein moving one, or both, of the first and third flow lines relative to the second and fourth manifolds, respectively, comprises moving one, or both, of the first and third trucks along the first and third rails, respectively; and wherein moving one, or both, of the second and fourth flow lines relative to the second and fourth manifolds, respectively, comprises moving one, or both, of the second and fourth trucks along the second and fourth rails, respectively.
14. The method of claim 12, wherein the second manifold comprises a fifth flow line and the fourth manifold comprises a sixth flow line; wherein mounting the first and second manifolds to the first skid comprises supporting the second manifold in an elevated position above the first manifold so that the fifth flow line is vertically offset from the first and second flow lines; and wherein mounting the third and fourth manifolds to the second skid comprises supporting the fourth manifold in an elevated position above the third manifold so that the sixth flow line is vertically offset from the third and fourth flow lines.
15. The method of claim 10, wherein the second manifold comprises a fifth flow line and the fourth manifold comprises a sixth flow line; wherein the first, second, and fifth flow lines define first, second, and third inner diameters, respectively, the third inner diameter being greater than the first and second inner diameters; and wherein the third, fourth, and sixth flow lines define fourth, fifth, and sixth inner diameters, respectively, the sixth inner diameter being greater than the fourth and fifth inner diameters.
16. The method of claim 9, further comprising: providing a zipper manifold adapted to convey the pressurized fluid from the second manifold to the wellbore and at least one other wellbore extending in the subterranean formation to hydraulically fracture the subterranean formation in which the wellbore and the at least one other wellbore extend.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
(15) Turning to
(16) The manifold assemblies 12 and 14 are identical to one another, and, therefore, in connection with
(17) Turning to
(18) Turning to
(19) The skid 40 also includes lifting tabs 52a-d and transport brackets 54a-d. The lifting tabs 52a and 52b are connected to a transversely-extending structural member (not shown) extending between the transversely-extending structural members 48a and 48b and connected to the longitudinally-extending structural members 44a and 44b. The lifting tabs 52c and 52d are connected to another transversely-extending structural member (not shown) extending between the transversely-extending structural members 48b and 48c and connected to the longitudinally-extending structural members 44a and 44b. The transport brackets 54a and 54c are connected to the longitudinally-extending structural member 44a, and the transport brackets 54b and 54d are connected to the longitudinally-extending structural member 44b. The transport brackets 54a and 54b are adapted to support flow line components (not visible in
(20) In addition, the skid 40 includes a pair of longitudinally-extending rails 58a and 58b connected to the carriage plates 50a and 50b. The longitudinally-extending rails 58a and 58b support trucks 60a-d. The trucks 60a-d are movable along the rails 58a or 58b in opposing longitudinal directions, as indicated by arrows 62 and 64, to permit alignment and connection of the manifold assembly 12's low pressure manifold 36 with the corresponding low pressure manifold (not visible in
(21) The trucks 60a-d are identical to one another and, therefore, in connection with
(22) Turning to
(23) The flow lines 84a and 84b each include valves 86a and 86b such as, for example, butterfly valves, at or near opposing end portions thereof. The flow lines 84a and 84b each include handles 88a and 88b extending therefrom to facilitate movement of the flow lines 84a and 84b along the longitudinally-extending rails 58a and 58b via the trucks 60a-d in the opposing longitudinal directions 62 and 64. The flow lines 84a and 84b each include a locking tab 90 adapted to engage the skid 40's locking tabs 66a or 66b to secure the manifold assembly 12's low pressure manifold 36 in place after the low pressure manifold 36 is aligned with, and connected to, the corresponding low pressure manifold of the manifold assembly 14.
(24) The hydraulic fracturing pumps 18a, 18b, and 18c (shown in
(25) The hydraulic fracturing pumps 18d, 18e and 18f (shown in
(26) The high pressure modules 42a-c are identical to one another, and, therefore, in connection with
(27) The high pressure module 42a's fluid block 104 is connected to the corresponding fluid block 104 of the high pressure module 42b via a longitudinally-extending tubular member, or flow line 112, and the high pressure module 42b's fluid block 104 is connected to the corresponding fluid block 104 of the high pressure module 42c via a longitudinally-extending tubular member, or flow line 114. More particularly, the respective fluid blocks 104 of the high pressure modules 42a and 42b are connected to opposing end portions of the flow line 112, and the respective fluid blocks 104 of the high pressure modules 42b and 42c are connected to opposing end portions of the flow line 114. As a result, the respective vertical supports 108 of the high pressure modules 42a-c are adapted to support the respective fluid blocks 104 and the flow lines 112 and 114 in an elevated position above the skid 40 (or the another horizontal surface).
(28) The hydraulic fracturing pumps 18a, 18b, and 18c (shown in
(29) Turning to
(30) Turning to
(31) The fluid block 126a is connected to the flow line 128a and supported by the vertical support 132a in an elevated position above the skid 124 at or near the transversely-extending end member 46a (visible in
(32) In an embodiment, side ports 134a and 134b (visible in
(33) Turning to
(34) Turning to
(35) In an embodiment, side ports 152a and 152b (visible in
(36) Turning to
(37) Turning to
(38) The manifold assembly 12's flow line 84a is displaced via the associated trucks 60a and 60b in the longitudinal direction 62, and/or the manifold assembly 14's flow line 84a is displaced via the associated trucks 60a and 60b in the longitudinal direction 64, as shown in
(39) The manner in which the flow line 118b is connected between the respective flow lines 84b of the manifold assemblies 12 and 14 is substantially identical to the manner in which the flow line 118a is connected between the respective flow lines 84a of the manifold assemblies 12 and 14, and, therefore, will not be described in further detail. The jacks 56a-d may be connected to the skid 40 and lowered to support the manifold assembly 14 before, during, or after, the connection of the flow line 120 between the fluid block 104 of the manifold assembly 12's high pressure module 42c and the fluid block 104 of the manifold assembly 14's high pressure module 42a, as shown in
(40) In operation, the hydraulic fracturing fluid is prepared in the blender 16 and communicated to the pressurization manifold 22 via the rear header 26. The respective valves 86a of the manifold assembly 12's flow lines 84a and 84b are opened to permit communication of the hydraulic fracturing fluid from the rear header 26 to the flow lines 84a and 84b via the flow lines 116a and 116b. Moreover, the respective valves 86b of the manifold assembly 12's flow lines 84a and 84b, and the respective valves 86b of the manifold assembly 14's flow lines 84a and 84b, are opened to permit communication of the hydraulic fracturing fluid from the low pressure manifold 36 of the manifold assembly 12 to the low pressure manifold 36 of the manifold assembly 14 via the flow lines 118a and 118b. The respective valves 86b of the manifold assembly 14's flow lines 84a and 84b are closed to cap the low pressure manifold 36 of the manifold assembly 14. The hydraulic fracturing fluid is communicated from the manifold assembly 12's low pressure manifold 36 to the respective hydraulic fracturing pumps 18a-f via one (or both) of outlet ports 92a and 92b, one (or both) of outlet ports 94a and 94b, and one (or both) of outlet ports 96a and 96b, one (or both) of outlet ports 98a and 98b, one (or both) of outlet ports 100a and 100b, and one (or both) of outlet ports 102a and 102b. The hydraulic fracturing pumps 1 8a-f receive, pressurize, and communicate the hydraulic fracturing fluid to the associated high pressure module 42a 42b, or 42c of the manifold assembly 12's high pressure manifold 38. The blind flange 119 connected to the fluid block 104 of the manifold assembly 12's high pressure module 42a prevents communication of the hydraulic fracturing fluid to atmosphere. In a similar manner, the hydraulic fracturing fluid is communicated from the manifold assembly 14's low pressure manifold 36 to the respective hydraulic fracturing pumps 18g-1, and from the respective hydraulic fracturing pumps 18g-1 to the manifold assembly 14's high pressure modules 42a, 42b, or 42c.
(41) The hydraulic fracturing fluid is communicated from the pressurization manifold 22 to the valve assembly 32 via the respective fluid blocks 104 of the manifold assembly 12's high pressure modules 42a-c, the manifold assembly 12's flow lines 112 and 114, the flow line 120 connected between the fluid block 104 of the manifold assembly 12's high pressure module 42c and the fluid block 104 of the manifold assembly 14's high pressure module 42a, the respective fluid blocks 104 of the manifold assembly 14's high pressure modules 42a-c, the manifold assembly 14's flow lines 112 and 114, and the flow line 138 connected between the fluid block 104 of the manifold assembly 14's high pressure module 42c and the valve assembly 32's fluid block 126a.
(42) The hydraulic fracturing fluid is communicated from the valve assembly 32 to the iron assembly 30 via the fluid block 126a, the flow line 128a, the valve 130a, the valve 130b, the valve 130c, the flow line 128b, the fluid block 126b, and the flow line 140 connected between the valve assembly 32's fluid block 126b and the iron assembly 30's fluid block 146a. In those embodiments in which the valves 130a and 130b are plug valves, the valves 130a and 130b are operable to selectively prevent communication of the hydraulic fracturing fluid from the manifold assembly 14 to the iron assembly 30 via the valve assembly 32. In those embodiments in which the valve 130b is a check valve, the valve 130b is operable to prevent backflow of the hydraulic fracturing fluid from the iron assembly 30 to the manifold assembly 14 via the valve assembly 32. In some embodiments, during the communication of the hydraulic fracturing fluid from the valve assembly 32 to the iron assembly 30, at least one of the side ports 134a, 134b, 136a and 136b of the fluid blocks 126a or 126b is used to establish fluid communication with the fluid conduit 122 and to support instrumentation (not shown) for measuring one or more characteristics of the hydraulic fracturing fluid exiting the respective high pressure manifolds 38 of the manifold assemblies 12 and 14.
(43) The hydraulic fracturing fluid is communicated from the iron assembly 30 to the zipper manifold 34 via the fluid block 146a, the flow line 148a, the flow line 148b, the fluid block 146b, and the flow line 156 connected between the iron assembly 30's fluid block 146b and the zipper manifold 34. In some embodiments, during the communication of the hydraulic fracturing fluid from the iron assembly 30 to the zipper manifold 34, at least one of the side ports 152a, 152b, 154a and 154b of the fluid blocks 146a or 146b is used to establish fluid communication with the fluid conduit 142 and to support instrumentation (not shown) for measuring one or more characteristics of the hydraulic fracturing fluid exiting the respective high pressure manifolds 38 of the manifold assemblies 12 and 14.
(44) The system 10 has been described herein as including the manifold assemblies 12 and 14, the valve assembly 32, and the iron assembly 30; however, the iron assembly 30 may be omitted and the valve assembly 32 may instead be connected between the manifold assembly 14 and the zipper manifold 34; the valve assembly 32 may be omitted and the iron assembly may instead be connected between the manifold assembly 14 and the zipper manifold; or the iron assembly 30 and the valve assembly 32 may be omitted and the manifold assembly 14 may be connected to the zipper manifold 34. Moreover, systems analogous to the system 10 are contemplated in which varying numbers of manifold assemblies, valve assemblies, and iron assemblies are used to construct the system depending on the particular requirements of the fracturing job.
(45) In some embodiments, the flow lines 84a and 84b of the manifold assembly 12's low pressure manifold 36 define first and second inner diameters, respectively, and the flow lines 112 and 114 of the manifold assembly 12's high pressure manifold 38 each define a third inner diameter, the third inner diameter being greater than the first and second inner diameters. In some embodiments, fluid blocks 104 of the manifold assembly 12's high pressure modules 42a-c each define an inner diameter substantially the same as the third inner diameter. In some embodiments, the flow lines 84a and 84b of the manifold assembly 14's low pressure manifold 36 define fourth and fifth inner diameters, respectively, and the flow lines 112 and 114 of the manifold assembly 14's high pressure manifold 38 each define a sixth inner diameter, the sixth inner diameter being greater than the fourth and fifth inner diameters. In some embodiments, fluid blocks 104 of the manifold assembly 14's high pressure modules 42a-c each define an inner diameter substantially the same as the sixth inner diameter. In several embodiments, the third and sixth inner diameters are about 5⅛ inches, are greater than about 5⅛ inches, range from about 5⅛ inches to about 7 1/16 inches, or are about 7 1/16 inches.
(46) In some embodiments, the flow lines 128a and 128b of the valve assembly 32 each define a seventh inner diameter, the seventh inner diameter being about the same as the third and sixth inner diameters of the manifold assemblies 12 and 14, respectively. In some embodiments, the fluid blocks 126a and 126b and/or the valves 130a-130c of the valve assembly 32 each define an inner diameter substantially the same as the seventh inner diameter. In some embodiments, the components (i.e., the one or more hoses, p1pmg, swivels, flowline components, other components, or any combination thereof) used to establish fluid communication with the fluid block 126a or 126b via the side ports 134a and 134b or the side ports 136a and 136b, respectively, each define an inner diameter smaller than the inner diameter of the fluid blocks 126a and 126b. For example, such components (and/or the side port(s) 134a, 134b, 136a, or 136b) may define an inner diameter of about 3 inches, and the fluid blocks 126a and 126b may define an inner diameter of about 7 inches.
(47) In some embodiments, the flow lines 148a and 148b of the iron assembly 30 each define an eighth inner diameter, the eighth inner diameter being about the same as the third and sixth inner diameters of the manifold assemblies 12 and 14, respectively. In some embodiments, the fluid blocks 146a and 146b of the iron assembly 30 each define an inner diameter substantially the same as the eighth inner diameter. In some embodiments, the components (i.e., the one or more hoses, piping, swivels, flowline components, other components, or any combination thereof) used to establish fluid communication with the fluid block 146a or 146b via the side ports 152a and 152b or the side ports 154a and 154b, respectively, each define an inner diameter smaller than the inner diameter of the fluid blocks 146a and 146b. For example, such components (and/or the side port(s) 152a, 152b, 154a, or 154b) may define an inner diameter of about 3 inches, and the fluid blocks 146a and 146b may define an inner diameter of about 7 inches.
(48) In some embodiments, the hydraulic fracturing system 10 described herein decreases setup time and labor costs, provides adjustability, decreases safety risks associated with potential leak points, and/or increases pumping efficiency during hydraulic fracturing operations. As a result, in some embodiments, the hydraulic fracturing system 10 increases the overall effectiveness of fracturing operations, thereby enabling operators to effective address challenges such as, for example, continuous duty operations, harsh downhole environments, and multiple extended-reach lateral wells, among others.
(49) It is understood that variations may be made in the foregoing without departing from the scope of the present disclosure.
(50) In some embodiments, the elements and teachings of the various embodiments may be combined in whole or in part in some or all of the embodiments. In addition, one or more of the elements and teachings of the various embodiments may be omitted, at least in part, and/or combined, at least in part, with one or more of the other elements and teachings of the various embodiments.
(51) In some embodiments, while different steps, processes, and procedures are described as appearing as distinct acts, one or more of the steps, one or more of the processes, and/or one or more of the procedures may also be performed in different orders, simultaneously and/or sequentially. In some embodiments, the steps, processes and/or procedures may be merged into one or more steps, processes and/or procedures.
(52) In some embodiments, one or more of the operational steps in each embodiment may be omitted. Moreover, in some instances, some features of the present disclosure may be employed without a corresponding use of the other features. Moreover, one or more of the above-described embodiments and/or variations may be combined in whole or in part with any one or more of the other above-described embodiments and/or variations.
(53) In the foregoing description of certain embodiments, specific terminology has been resorted to for the sake of clarity. However, the disclosure is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes other technical equivalents which operate in a similar manner to accomplish a similar technical purpose. Terms such as “left” and right”, “front” and “rear”, “above” and “below” and the like are used as words of convenience to provide reference points and are not to be construed as limiting terms.
(54) In this specification, the word “comprising” is to be understood in its “open” sense, that is, in the sense of “including”, and thus not limited to its “closed” sense, that is the sense of “consisting only of’. A corresponding meaning is to be attributed to the corresponding words “comprise”, “comprised” and “comprises” where they appear.
(55) Although some embodiments have been described in detail above, the embodiments described are illustrative only and are not limiting, and those skilled in the art will readily appreciate that many other modifications, changes and/or substitutions are possible in the embodiments without materially departing from the novel teachings and advantages of the present disclosure. Accordingly, all such modifications, changes, and/or substitutions are intended to be included within the scope of this disclosure as defined in the following claims. In the claims, any means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Moreover, it is the express intention of the applicant not to invoke 35 U.S.C. § 112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the word “means” together with an associated function.