Not applicable.
Reciprocating pumps (e.g., piston pumps, plunger pumps, diaphragm pumps, etc.) are used in a variety of applications for providing fluid flow. For instance, for the recovery of hydrocarbons or minerals from a subsurface formation using a drilling system, it is typical practice to connect a drill bit onto the lower end of a drillstring formed from a plurality of pipe joints connected together end-to-end, and then rotate the drillstring so that the drill bit progresses downward into the earth to create a borehole along a predetermined trajectory. Drilling fluid or “mud” is typically pumped under pressure down the drillstring using a mud pump located at the surface. The drilling mud flows out of a face of the drill bit and into the borehole, and then up the annulus between the drillstring and the borehole sidewall to the surface. Mud pumps often comprise plunger or piston reciprocating pumps having multiple plungers/pistons (e.g., duplex pumps, triplex pumps, quintuplex pumps, etc.) that are configured to circulate the drilling mud under high pressure (e.g., pressures greater than 1,000 pounds per square inch (PSI)). Mud pumps typically comprise a fluid end that receives a suction flow of drilling mud and outputs a discharge flow of pressurized drilling mud, and a power end that provides the reciprocating motion to the one or more plungers/pistons of the mud pump responsible for creating the suction and discharge fluid flows.
An embodiment of a reciprocating pump system comprises a reciprocating pump including a fluid end configured to receive a suction fluid flow and discharge a discharge fluid flow, and a suction booster assembly coupled to the fluid end, the suction booster assembly comprising a venturi including a venturi passage, and a jet configured to jet a fluid received from the discharge of the fluid end into the venturi passage, wherein the suction booster assembly is configured such that the jet of the suction booster assembly jetting the fluid into the venturi passage increases the pressure of the suction fluid flow. In some embodiments, the suction booster assembly comprises an inlet adapter coupled to the venturi, wherein the inlet adapter comprises a central passage and an angled passage spaced from the central passage that receives the jet. In some embodiments, the jet of the suction booster assembly includes a nozzle extending along a jet axis disposed at a non-zero angle to a central axis of the venturi passage. In certain embodiments, the suction booster assembly comprises a plurality of jets configured to jet the fluid received from the discharge of the fluid end into the venturi passage, and wherein the inlet adapter comprises a plurality of angled passages circumferentially spaced about the central passage of the inlet adapter. In certain embodiments, the inlet adapter of the suction booster assembly has an outer surface comprising an annular channel that is in fluid communication with the plurality of angled passages. In some embodiments, the venturi passage of the suction booster assembly is defined by an inner surface that comprises a converging section, a throat, and a diverging section. In some embodiments, the system further comprises a backflow line configured to divert a portion of the discharge fluid flow to the jet of the suction booster assembly, wherein the backflow line includes a filter coupled to the backflow line and configured to filter debris from the discharge fluid flow provided to the jet. In certain embodiments, the system further comprises a bypass line including a first end coupled to the backflow line at a first location that is upstream of a first valve of the bypass line, and a second end coupled to the backflow line at a second location that is between the filter and a second valve of the bypass line, and a drain line including a first end coupled to the backflow line at a third location that is between the first valve of the backflow line and the filter, wherein the bypass line is configured to backflush the filter in response to closing the first valve and the second valve of the backflow line. In certain embodiments, the system further comprises a pulsation dampener coupled to the fluid end of the reciprocating pump and the suction booster assembly, wherein the pulsation dampener is configured to dampen pulsations in pressure or flowrate of the suction fluid flow received by the fluid end.
An embodiment of a jet pump for increasing suction pressure of a reciprocating pump comprises a venturi including a venturi passage, and an inlet adapter coupled to the venturi and comprising a central passage and an angled passage that receives a jet, wherein the jet includes a nozzle extending along a jet axis disposed at a non-zero angle to a central axis of the venturi passage. In some embodiments, the angled passage is radially spaced from the central passage of the inlet adapter. In some embodiments, the jet pump further comprises a plurality of jets each including a nozzle extending along a jet axis disposed at non-zero angles to the central axis of the venturi passage, wherein the inlet adapter comprises a plurality of angled passages circumferentially spaced about the central passage of the inlet adapter. In certain embodiments, the inlet adapter of the suction booster assembly has an outer surface comprising an annular channel that is in fluid communication with the plurality of angled passages. In certain embodiments, the venturi passage is defined by an inner surface that comprises a converging section, a throat, and a diverging section. In some embodiments, the jet axis intersects the central axis of the venturi passage of the jet pump at a location in the venturi passage that, in a side view of the venturi passage, is defined by the diverging section of the inner surface of the venturi passage. In some embodiments, the inlet adapter comprises a radial port in fluid communication with the angled passage, and wherein the inlet adapter is configured to receive a portion of a fluid flow discharged by the reciprocating pump.
An embodiment of a method for increasing suction pressure of a reciprocating pump comprises (a) diverting a portion of a discharge fluid flow from a discharge line coupled to the reciprocating pump, (b) increasing a flow velocity of the diverted discharge fluid flow by jetting the diverted discharge fluid flow from a nozzle of a jet, (c) jetting the diverted discharge fluid flow into a suction fluid flow, and (d) flowing the suction fluid flow through a venturi passage. In some embodiments, the method further comprises (e) increasing the flow velocity of the diverted discharge fluid flow by jetting the diverted discharge fluid flow from a plurality of jets that are radially spaced from a central axis of the venturi passage. In some embodiments, the method further comprises (e) jetting the diverted discharge fluid flow into the suction fluid flow along a jet axis that is disposed at a non-zero angle to a central axis of the venturi passage. In certain embodiments, the method further comprises (e) flowing the suction fluid flow through a pulsation dampener coupled to the reciprocating pump. In certain embodiments, the method further comprises (e) flowing the diverted discharge fluid flow through a filter located upstream of the jet, and (f) reversing a direction of the diverted discharge fluid flow through the filter to remove debris from the filter.
For a detailed description of disclosed exemplary embodiments, reference will now be made to the accompanying drawings in which:
The following discussion is directed to various embodiments. However, one skilled in the art will understand that the examples disclosed herein have broad application, and that the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that embodiment. The drawing figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in interest of clarity and conciseness.
In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . ” Also, the term “couple” or “couples” is intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct engagement or connection of the two devices, or through an indirect connection as accomplished via other intermediate devices, components, and connections. In addition, as used herein, the terms “axial” and “axially” generally mean along or parallel to a central axis (e.g., central axis of a body or a port), while the terms “radial” and “radially” generally mean perpendicular to the central axis. For instance, an axial distance refers to a distance measured along or parallel to the central axis, and a radial distance means a distance measured perpendicular to the central axis. Any reference to up or down in the description and the claims is made for purposes of clarity, with “up”, “upper”, “upwardly”, “uphole”, or “upstream” meaning toward the surface of the borehole and with “down”, “lower”, “downwardly”, “downhole”, or “downstream” meaning toward the terminal end of the borehole, regardless of the borehole orientation.
Referring to
In some embodiments, BHA 40 may include a downhole mud motor for converting the fluid pressure of the drilling fluid pumped downward through drillstring 21 by mud pump system 100 into rotational torque for driving the rotation of drill bit 90. With force or weight applied to the drill bit 90, also referred to as weight-on-bit (“WOB”), the rotating drill bit 90 engages the earthen formation and proceeds to form borehole 16 along a predetermined path toward a target zone. The drilling fluid or mud pumped down the drillstring 21 and through BHA 30 passes out of the face of drill bit 90 and back up the annulus 18 formed between drillstring 21 and the wall 19 of borehole 16. The drilling fluid cools the bit 90, and flushes the cuttings away from the face of bit 90 and carries the cuttings to the surface 7 where the recirculated drilling fluid is received in a fluid source or mud pit 42. At the surface 7 the drilling fluid recirculated from borehole 16 may be conditioned or treated (e.g., to remove drill cuttings or other debris from the drilling fluid, etc.) prior to being pumped back into drillstring 21 via mud pump system 100 and kelly 40.
Referring to
In this embodiment, each fluid end module 116 of fluid end 110 includes a cylindrical bore that receives a piston or plunger. Mud pump system 100 also includes a power end (not shown in
The power end of mud pump system 100 includes a reciprocating drive (e.g., crankshaft, connecting rods, etc.) that reciprocates the plungers/pistons through their respective cylindrical bores formed in fluid end module 116. Particularly, each plunger/piston of pump 115 includes a suction stroke where the plunger/piston travels draws fluid into its respective fluid end module 116 from suction manifold 112, and a discharge stroke where the plunger/piston discharges fluid from its respective fluid end module 116 into discharge manifold 114. Given that pump 115 discharges drilling fluid into discharge line 120 via the reciprocating movement of its respective plungers/pistons, the flow rate of drilling fluid discharged from pump 115 varies over time. In other words, pump 115 provides a pulsating flow of fluid (e.g., pulsating fluid flowrate and/or fluid velocity over time) from suction line 102 into pump 115, and from pump 115 into discharge line 120. Additionally, the resistance of drilling fluid flowing through suction line 102 to accelerations or changes in fluid flowrate and/or fluid velocity (e.g., the impedance of the drilling fluid) may periodically or intermittently decrease the amount of Net Positive Suction Head (NPSH) provided to the suction manifold 112 by the drilling fluid flowing through suction line 102, a phenomena sometimes referred to as “acceleration head.” As will be described further herein, suction booster assembly 200, which is disposed between suction line 102 and suction manifold 112, is configured to boost the pressure or NPSH provided to suction manifold 112 to prevent cavitation in the drilling fluid flowing into suction manifold 112 that may result from insufficient NPSH.
In this embodiment, mud pump system 100 also includes a backflow line or conduit 130 extending between discharge line 120 and suction booster assembly 200. As will be described further herein, backflow line 130 diverts or bleeds a portion of the drilling fluid flowing through discharge line 120 to suction booster assembly 200. In this embodiment, backflow line 130 diverts approximately 5%-20% from discharge line 120 to suction booster assembly 200; however, in other embodiments, the percentage of drilling fluid diverted from discharge line 120 by backflow line 130 may vary. Additionally, in this embodiment, backflow line 130 includes a filter 132 for filtering out particulates of a predetermined size from the drilling fluid flowing through backflow line 130 towards suction booster assembly 200.
Referring to
The outer surface 208 of inlet adapter 202 includes an annular groove or channel 210 extending radially therein and a pair of annular seals 212 disposed therein, where one seal 212 is positioned adjacent each side of channel 210 to restrict fluid communication between channel 210 and the environment surrounding suction booster assembly 200. Inlet adapter 202 additionally includes a plurality of circumferentially spaced angled passages 214 (shown schematically in
Outlet adapter 240 of suction booster assembly 200 is generally cylindrical and has a first or inlet end 240A, a second or outlet end 240B opposite inlet end 240A, and a central bore or passage 242 defined by a generally cylindrical inner surface 244 extending between ends 240A, 240B. In this embodiment, the outlet end 240B of outlet adapter 240 couples with an end of the suction manifold 112 of fluid end 110 (e.g., via releasable fasteners). Additionally, in this embodiment, the inner surface 244 of outlet adapter 240 includes an annular shoulder 246 extending axially from inlet end 240A of outlet adapter 240. Cylinder 250 of suction booster assembly 200 has a first end 250A, a second end 250B opposite first end 250A, and a central bore or passage defined by a generally cylindrical inner surface 252 extending between ends 250A, 250B. In this embodiment, cylinder 250 houses venturi 260 of suction booster assembly 200 and, in this embodiment, the inner surface 252 of cylinder 250 includes an annular groove 254 that receives an annular retainer 256 for releasably coupling venturi 260 with cylinder 250 such that relative axial movement between venturi 260 and cylinder 250 is substantially restricted.
Venturi 260 of suction booster assembly 200 is generally cylindrical and has a first or inlet end 260A, a second or outlet end 260B opposite inlet end 260A, a central bore or venturi passage 262 defined by a generally cylindrical inner surface 264 extending between ends 260A, 260B, and a generally cylindrical outer surface 266 extending between ends 260A, 260B. When venturi 260 is received in cylinder 250, the inlet end 260A of venturi 260 is axially aligned or positioned adjacent the first end 250A of cylinder while outlet end 260B of venturi 260 contacts or is disposed directly adjacent the retainer 256 positioned proximal second end 250B of cylinder 250. Additionally, when venturi 260 is received in cylinder 250, inlet end 260A of venturi 260 contacts or is disposed directly adjacent outlet end 202B of inlet adapter 202. In this embodiment, an annular seal 268 is positioned radially between the outer surface 266 of venturi 260 and the inner surface 252 of cylinder 250 to restrict fluid flow through the annular interface formed therebetween.
In This embodiment, the inner surface 264 of venturi passage 262 includes a first or frustoconical or converging section 264A extending axially from inlet end 260A, a second or throat 264B extending axially from an end of converging section 264A positioned distal inlet end 260A of venturi 260, and a frustoconical or diverging section 264C extending axially between an end of throat 264B located distal converging section 264A and the outlet end 260B of venturi 260. In this configuration, moving from inlet end 260A to outlet end 260B of venturi 260: passage 264 of venturi 260 converges from a first or inlet diameter located at inlet end 260A to a second or throat diameter D2 located at the interface between converging section 264A and throat 264B, where second diameter D2 is smaller than the inlet diameter D1 of the passage 204 of inlet adapter 202, and diverges or expands (beginning at the interface between throat 264B and diverging section 264C) from throat diameter D2 to a third or outlet diameter D3 located at, or proximal to, outlet end 260B of venturi 260, where outlet diameter D3 is greater than throat diameter D2. The diverging section 264C of venturi 260 is disposed at a taper or diffuser angle θ to venturi axis 265. In this embodiment, diffuser angle θ is 5°; however, in other embodiments, diffuser angle θ may vary. For instance, in some embodiments, diffuser angle θ of diverging section 264C may be approximately between 5°-10°.
In this embodiment, throat diameter D2 of venturi passage 262 is approximately 20%-40% smaller than the inlet diameter D1 of inlet adapter 202, and an axial throat length 267 of throat 264B is approximately 100%-125% the size of throat diameter D2 (e.g., the same size or up to 25% greater in size than throat diameter D2); however, in other embodiments, the relationship in size between throat diameter D2 and the inlet diameter D1 of inlet adapter 202, as well as the relationship in size between throat length 267 and throat diameter D2, may vary. Additionally, in this embodiment, the inlet diameter D1 of inlet adapter 202 is greater than outlet diameter D3 of venturi 260; however, in other embodiments, outlet diameter D3 of venturi passage 262 may the same or greater than inlet diameter D1. Venturi passage 262 of venturi 260 extends along a central or venturi axis 265, where the jet axis 215 of the nozzle 218 of each jet 216 is disposed at a jet angle α to venturi axis 265 (each jet 216 being radially spaced from venturi axis 265). In this embodiment, the jet angle α formed between venturi axis 265 and each jet axis 215 is 15°; however, in other embodiments, the jet angle α may vary. Moreover, in some embodiments, the jet angle α may vary between each jet 216 of suction booster assembly 200 such that jets 216 of assembly 200 are disposed at varying jet angles α to venturi axis 265. In this embodiment, the jet axis 215 of the nozzle 218 of each jet 216 is directed towards (but does not necessarily intersect) venturi axis 265 such that drilling fluid jetted from jets 216 flows towards or in the direction of venturi axis 265. In this embodiment, the jet axis 215 of the nozzle 218 of each jet 216 intersects venturi axis 265 in a side view of suction booster assembly 200 (e.g., the side, cross-sectional view of suction booster assembly 200 shown in
Housing 280 of suction booster assembly 200 is disposed about the outlet end 202B of inlet adapter 202 and the first end 250A of cylinder 250. In this embodiment, housing 280 is generally cylindrical and includes a first end 280A, a second end 280B opposite first end 280A, and a central bore or passage defined by a generally cylindrical inner surface 282 extending between ends 280A, 280B, and a generally cylindrical outer surface extending between ends 280A, 280B. In this embodiment, the inner surface 282 of housing 280 includes an annular shoulder 284 extending axially from second end 280B. Additionally, in this embodiment, housing 280 includes a radial port 286 (shown schematically in
In this embodiment, the first end 250A of cylinder 250 is welded to the inner surface 282 of housing 280 at shoulder 284 while the second end 250B of cylinder 250 is welded to the inner surface 244 of outlet adapter 240 at shoulder 246. In this manner, sealing engagement is provided at the welded interface between cylinder 250 and shoulder 284 of housing 280, as well as the welded interface between cylinder 250 and shoulder 246 of outlet adapter 240, to prevent fluid communication between venturi passage 262 of venturi 260 and the environment surrounding suction booster assembly 200. Additionally, in this embodiment, the outer surface 208 is releasably coupled to the inner surface 282 of housing 280. In other embodiments, inlet adapter 202, outlet adapter 240, cylinder 250, and housing 280 may be releasably coupled to each other, using annular seals to prevent fluid communication between venturi passage 262 of venturi 260 and the surrounding environment. In still other embodiments, inlet adapter 202, outlet adapter 240, cylinder 250, and housing 280 may be monolithically formed from a single body or member.
As described above, the impedance of drilling fluid flowing through suction line 102 may intermittently decrease the amount of NPSH provided to the suction manifold 112 by the drilling fluid flowing through suction line 102. Additionally, in at least some applications, cavitation may occur in the drilling fluid flowing into and through suction manifold 112 if a threshold or minimum NPSH is not provided to pump 115 during the operation of mud pump system 100, where cavitation may damage or otherwise inhibit the operation of mud pump system 100. Suction booster assembly 200 boosts or increases the pressure of drilling fluid flowing therethrough before the drilling fluid enters suction manifold 112, preventing or at least reducing the risk of the NPSH provided to suction manifold 112 falling below the minimum NPSH required to avoid cavitation.
Particularly, the fluid velocity of drilling fluid supplied to jets 216 of suction booster assembly 200 via backflow line 130 substantially increases as the drilling fluid is jetted from the flow restriction provided by the relatively small diameter of the nozzles 218 of jets 216. The interaction between the high velocity drilling fluid jetted into venturi passage 265 from jets 216 and the drilling fluid of a suction fluid flow 270 entering venturi 265 from the passage 204 of inlet adapter 202 increases the pressure of suction fluid flow 270 as suction fluid flow 270 flows through the diverging portion of venturi passage 262 defined by the diverging section 264C of inner surface 264. In other words, the pressure (P1) of suction fluid flow 270 flowing through passage 204 of inlet adapter 202 is less than the pressure (P2) of suction fluid flow 270 as suction fluid flow 270 exits venturi passage 265 at the outlet end 260B of venturi 260.
In this manner, suction booster assembly 200 increases the pressure of the suction fluid flow 270 entering suction manifold 112 of fluid end 110. Additionally, suction booster assembly 200 increases the pressure of suction fluid flow 270 without requiring external power or the use of moving parts. Thus, suction booster assembly 200 pressurizes suction fluid flow 270 in an inexpensive and space-efficient (e.g., relative to a centrifugal pump, for instance) manner. The space-efficiency of suction booster assembly 200 may be particularly advantageous in applications that require a compact pump system, such as offshore well systems. Further, by using a plurality of jets 216 rather than a single jet (e.g., a jet positioned in passage 204 of inlet adapter 202), the nozzle 218 of each jet 216 may be reduced to flow a fixed amount of drilling fluid therethrough to thereby maximize the increase in fluid velocity of the drilling fluid jetted from jets 216 while minimizing turbulence in suction fluid flow 270 as suction fluid flow 270 receives the high velocity drilling fluid jetted from jets 216. Moreover, by positioning jets 216 circumferentially about venturi axis 265 within the angled passages 214 of inlet adapter 202, the axial length (e.g., the axial length between the inlet end 202A of inlet adapter 202 and the outlet end 240B of outlet adapter 240) and overall size of suction booster assembly 200 may be minimized.
Referring to
Referring to
In this embodiment, valves 356A, 356B of backflow line 352 may be closed to allow drilling fluid diverted from discharge line 120 to flow into the outlet of filter 132 via bypass line 35, and out of the inlet of filter 132 to a drain via drain line 362. In this manner, the flow of fluid may be reversed through filter 132 to thereby flow particulates and debris captured by filter 132 from filter 132 into a drain via drain line 362, thereby increasing the service life of filter 132. In some embodiments, suction may be applied to drain line 362 to assist with removing collected particulates and debris from filter 132. During normal operation of mud pump system 350, bypass valve 360 and drain valve 364 may be closed to permit drilling fluid diverted from discharge line 120 to flow into suction booster assembly 200.
Referring to
The vessel 408 of pulsation dampener 402 retains a volume of drilling fluid therein during the operation of mud pump systems 400A, 400B, where the volume of drilling fluid received in vessel 408 acts to minimize variations in pressure and flowrate of drilling fluid (e.g., variations or pulsations introduced by equipment located upstream of pulsation dampener 402) flowing from pulsation dampener 402 into the suction manifold 112 of fluid end 110 which could otherwise cause cavitation or otherwise inhibit the operation of mud pump 115. Pulsation dampener 402 may be used in conjunction with a suction booster assembly (e.g., suction booster assembly 200) to both dampen pulsations and increase the pressure of drilling fluid flowing into suction manifold 112 of fluid end 110. For instance, in the embodiment of mud pump system 400A shown in
While disclosed embodiments have been shown and described, modifications thereof can be made by one skilled in the art without departing from the scope or teachings herein. The embodiments described herein are exemplary only and are not limiting. Many variations and modifications of the systems, apparatus, and processes described herein are possible and are within the scope of the disclosure. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims. Unless expressly stated otherwise, the steps in a method claim may be performed in any order. The recitation of identifiers such as (a), (b), (c) or (1), (2), (3) before steps in a method claim are not intended to and do not specify a particular order to the steps, but rather are used to simplify subsequent reference to such steps.
This application claims benefit of U.S. provisional patent application Ser. No. 62/580,294 filed Nov. 1, 2017, and entitled “Reciprocating Pump Systems,” which is hereby incorporated herein by reference in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/US2018/058255 | 10/30/2018 | WO | 00 |
Number | Date | Country | |
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62580294 | Nov 2017 | US |