U.S. patent application number 15/383051 was filed with the patent office on 2017-04-06 for pump assembly.
The applicant listed for this patent is Schlumberger Technology Corporation. Invention is credited to Rod Shampine, Hubertus V. Thomeer.
Application Number | 20170097000 15/383051 |
Document ID | / |
Family ID | 43649717 |
Filed Date | 2017-04-06 |
United States Patent
Application |
20170097000 |
Kind Code |
A1 |
Thomeer; Hubertus V. ; et
al. |
April 6, 2017 |
PUMP ASSEMBLY
Abstract
A pump has power and fluid ends wherein one or more of the drive
rods are offset from the plungers. An offset coupler connects a
drive rod to an offset plunger. A method includes connecting the
offset power end to the standard fluid end using the offset
coupler. A repair and maintenance system includes inventories of
standard fluid ends, power ends including offset power ends, and
adapters, and a population of in service pumps, whereby the pumps
can be repaired by removing and replacing the power ends from
inventory using the adaptor where the replacement power end unit is
offset. Another method includes removing and replacing the power
end with one from the inventory, wherein the adapter is used in the
case of an offset power end, whereby the offset and standard power
ends may be used interchangeably.
Inventors: |
Thomeer; Hubertus V.;
(Houston, TX) ; Shampine; Rod; (Houston,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Schlumberger Technology Corporation |
Sugar Land |
TX |
US |
|
|
Family ID: |
43649717 |
Appl. No.: |
15/383051 |
Filed: |
December 19, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13393634 |
Mar 1, 2012 |
9528508 |
|
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PCT/IB2010/053868 |
Aug 27, 2010 |
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15383051 |
|
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61239654 |
Sep 3, 2009 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04B 53/144 20130101;
Y10T 29/49236 20150115; F04B 53/147 20130101; F04B 1/16 20130101;
F04B 1/124 20130101; F04B 37/12 20130101 |
International
Class: |
F04B 53/14 20060101
F04B053/14; F04B 1/12 20060101 F04B001/12; F04B 1/16 20060101
F04B001/16 |
Claims
1. (canceled)
2. (canceled)
3. (canceled)
4. (canceled)
5. (canceled)
6. (canceled)
7. (canceled)
8. (canceled)
9. (canceled)
10. (canceled)
11. (canceled)
12. (canceled)
13. A pump assembly and maintenance system, comprising: a standby
inventory of standard fluid end assemblies comprising a standard
plunger and tie rod configuration; a standby inventory of a
plurality of different sets of power end units, wherein each set of
power end units has a different drive rod and tie rod configuration
with respect to the other power end sets, including at least one
set of offset power ends having an offset drive rod and tie rod
configuration with respect to the standard plunger and tie rod
configuration; a standby inventory of adapter units to connect the
offset power ends to the standard fluid ends; and a population of
pump assemblies in service, comprising in-service pump assemblies
comprising a said standard fluid end, a said adapter unit and a
said offset power end, whereby the in-service pump assemblies can
be repaired by removing the power end and replacing with a said
power end from the standby inventory thereof wherein the
replacement power end has a different drive rod and tie rod
configuration with respect to the removed power end.
14. The pump assembly and maintenance system of claim 13 wherein
the inventory of standard fluid end assemblies further comprises
interchangeable pump body modules, wherein the fluid end assemblies
comprise a plurality of the modules, whereby the in-service pump
assemblies can be repaired by removing and replacing the standard
fluid end assembly or one or more of the interchangeable pump body
modules.
15. The pump assembly and maintenance system of claim 13 or 11
wherein the inventory of power end units further comprise a set of
standard power ends having a drive rod and tie rod configuration
matching the standard plunger and tie rod configuration, and
wherein the population of in-service pump assemblies further
comprises pump assemblies comprising a standard power end coupled
directly to a standard fluid end.
16. (canceled)
17. (canceled)
18. (canceled)
19. (canceled)
20. (canceled)
21. (canceled)
22. (canceled)
23. (canceled)
24. (canceled)
25. A method, comprising: providing a standby inventory of standard
fluid end assemblies comprising a standard plunger and tie rod
configuration; providing a standby inventory of a plurality of
different sets of power end units, wherein each set of power end
units has a different drive rod and tie rod configuration with
respect to the other power end sets, including at least one set of
offset power ends having an offset drive rod and tie rod
configuration with respect to the standard plunger and tie rod
configuration; providing a standby inventory of adapter units
adapted to connect the offset power ends to the standard fluid
ends; and connecting a said standard fluid end, a said adapter unit
and a said offset power end from the standby inventories into a
pump assembly; placing a plurality of the pump assemblies in
service; removing the power end of one of the in-service pump
assemblies for repair or maintenance and replacing it with a said
power end from the standby inventory, wherein the replacement power
end has a different drive rod and tie rod configuration with
respect to the removed power end.
26. The method of claim 25 wherein the inventory of standard fluid
end assemblies further comprises interchangeable pump body modules,
wherein the fluid end assemblies comprise a plurality of the
modules, and further comprising removing the standard fluid end
assembly or one or more of the interchangeable pump body modules
for repair or maintenance and replacing it with another one from
the inventory of standard fluid end assembly or one or more of the
interchangeable pump body modules.
27. The method of claim 25 wherein the inventory of power end units
further comprise a set of standard power ends having a drive rod
and tie rod configuration matching the standard plunger and tie rod
configuration, and further comprising connecting a said standard
fluid end and a said standard power end from the respective
inventories into a pump assembly.
Description
BACKGROUND OF THE INVENTION
[0001] (1) Field of the Invention
[0002] The invention is related in general to wellsite surface
equipment such as fracturing pumps and the like.
[0003] (2) Description of Related Art including information
disclosed under 37 CFR 1.97 and 1.98
[0004] Multiplex reciprocating pumps are generally used to pump
high pressure fracturing fluids downhole. Typically, the pumps that
are used for this purpose have plunger sizes varying from about 9.5
cm (3.75 in.) to about 16.5 cm (6.5 in.) in diameter. These pumps
typically have two sections: (a) a power end, the motor assembly
that drives the pump plungers (the driveline and transmission are
parts of the power end); and (b) a fluid end, the pump container
that holds and discharges pressurized fluid.
[0005] In triplex pumps, the fluid end has three fluid cylinders.
For the purpose of this document, the middle of these three
cylinders is referred to as the central cylinder, and the remaining
two cylinders are referred to as side cylinders. Similarly, a
quintuplex pump has five fluid cylinders, including a middle
cylinder and four side cylinders. A fluid end may comprise a single
block having cylinders bored therein, known in the art as a
monoblock fluid end.
[0006] The pumping cycle of the fluid end is composed of two
stages: (a) a suction cycle: During this part of the cycle a piston
moves outward in a packing bore, thereby lowering the fluid
pressure in the fluid end. As the fluid pressure becomes lower than
the pressure of the fluid in a suction pipe (typically 2-3 times
the atmospheric pressure, approximately 0.28 MPa (40 psi)), the
suction valve opens and the fluid end is filled with pumping fluid;
and (b) a discharge cycle: During this cycle, the plunger moves
forward in the packing bore, thereby progressively increasing the
fluid pressure in the pump and closing the suction valve. At a
fluid pressure slightly higher than the line pressure (which can
range from as low as 13.8 MPa (2 Ksi) to as high as 145 MPa (21
Ksi)) the discharge valve opens, and the high pressure fluid flows
through the discharge pipe.
[0007] The power end typically includes an engine such as a diesel
or gasoline engine, a transmission and a driveline that provides
the motive force to reciprocate the pump plungers via rods which
are known in the art as pony rods. Often the power ends and fluid
ends from different manufacturers are incompatible due to the
misalignment of the pony rods and plungers, as well as different
profiles and bolting patterns of the attachment flange of the power
end relative to the connection block on the fluid end. Power ends
may be produced by various manufacturers with considerable
variability in the design and/or dimensions of the attachment
flange, pony rods, driveline, etc., both between manufacturers as
well as between different models from the same manufacturer.
[0008] Given a pumping frequency of 2 Hz, i.e., 2 pressure cycles
per second, the fluid end body can experience a very large number
of stress cycles within a relatively short operational lifespan.
These stress cycles, together with the high operating pressures,
the difficult nature of the fluids being pumped, and often extreme
environmental conditions, gives rise to high maintenance
requirements both on the fluid end as well as the power end.
[0009] Frequently it is desired to remove power end and/or fluid
end pump assembly components from a working pump and replace them
with components from inventory to keep the pump assembly in
operation while the removed component can be repaired and returned
to inventory; however, there are substantial differences between
different pump assembly makes and models such that a relatively
large inventory is required to provide suitable replacement power
ends and/or fluid ends for every type an enterprise may have in
operation. A power end from one manufacturer, for example, may not
have the proper orientation of drive rods and tie rods to the fluid
end of another manufacturer, or the appropriate stroke length.
Standardization of fluid ends and pump ends for one manufacturer
can lead to sourcing and pricing issues and for these reasons it is
advantageous to have a wide range of suppliers for the various pump
components.
[0010] It remains desirable to provide improvements in wellsite
surface equipment in efficiency, flexibility, reliability, and
maintainability.
BRIEF SUMMARY OF THE INVENTION
[0011] The present invention in one embodiment uses an adapter to
connect up a power end to a fluid end of a pump assembly where the
power end has drive rods that are offset from the plungers of the
fluid end. In this embodiment non-standard power ends of different
makes and models can be interchangeably adapted for use with the
same fluid end.
[0012] In one embodiment, a pump assembly comprises: a power end
comprising a plurality of reciprocatable drive rods arranged in a
first geometric pattern; a fluid end comprising a plurality of
plungers arranged in a second geometric pattern wherein the second
geometric pattern is different from the first geometric pattern;
and an adaptor to connect the power end to the fluid end, wherein
the adaptor comprises an offset coupler to attach a said drive rod
to an offset one of the plungers.
[0013] In an embodiment, the adaptor further comprises an in-line
coupler to attach a said drive rod to an aligned one of the
plungers. In an embodiment, the first and second geometric patterns
comprise a straight line, wherein the drive rods and plungers are
transversely oriented on opposite sides of the line, and wherein
spacing between the drive rods is different from spacing between
the plungers. In an embodiment, the pump assembly has a triplex or
quintuplex fluid end wherein a middle one of the plungers is
coupled in alignment with a corresponding middle one of the drive
rods, and wherein side ones of the plungers are connected with
corresponding side ones of the drive rods using a respective
plurality of the offset couplers.
[0014] In an embodiment, the offset coupler comprises an eccentric
clamp, which may comprise a split housing halves, a first opening
and recess to receive the drive rod and an enlarged end thereof, a
second opening and recess to receive the plunger and an enlarged
end thereof, and a plurality of bolts to removable secure the
housing halves.
[0015] In an embodiment, the adaptor further comprises a plurality
of tie rods secured at opposite ends to the power end and the fluid
end, wherein at least one of the tie rods includes an offset tie
rod adapter to attach a first tie rod section from the power end
with an offset second tie rod section from the fluid end.
[0016] In an embodiment, the offset tie rod adaptor comprises
opposing first and second elongated blocks abutting at a sloping
transverse surface, a through bore and a threaded bore formed in
each of the first and second blocks, wherein the through bores of
the first and second blocks are aligned at the transverse surface
with the threaded bores of the respective second and first blocks,
wherein the through bores are formed longitudinally in a portion of
the blocks that is longer than a portion of the blocks in wherein
the threaded bores are formed, wherein the first tie rod section is
slideably received in the through bore of the first block and
threadedly engaged in the threaded bore of the second block and
wherein the second tie rod section is slideably received in the
through bore of the second block and threadedly engaged in the
threaded bore of the first block.
[0017] In an embodiment, the fluid end comprises a plurality of
pump body modules secured together to form the fluid end, for
example, in a line with fasteners between opposite end plates.
[0018] In another embodiment, a pump assembly and maintenance
system, comprises: a standby inventory of standard fluid end
assemblies comprising a standard plunger and tie rod configuration;
a standby inventory of a plurality of different sets of power end
units, wherein each set of power end units has a different drive
rod and tie rod configuration with respect to the other power end
sets, including at least one set of offset power ends having an
offset drive rod and tie rod configuration with respect to the
standard plunger and tie rod configuration; a standby inventory of
adapter units to connect the offset power ends to the standard
fluid ends; and a population of pump assemblies in service,
comprising in-service pump assemblies comprising a said standard
fluid end, a said adapter unit and a said offset power end, whereby
the in-service pump assemblies can be repaired by removing the
power end and replacing with a said power end from the standby
inventory thereof wherein the replacement power end has a different
drive rod and tie rod configuration with respect to the removed
power end.
[0019] In an embodiment, the inventory of standard fluid end
assemblies further comprises interchangeable pump body modules,
wherein the fluid end assemblies comprise a plurality of the
modules, whereby the in-service pump assemblies can be repaired by
removing and replacing the standard fluid end assembly or one or
more of the interchangeable pump body modules. In an embodiment,
the inventory of power end units further comprise a set of standard
power ends having a drive rod and tie rod configuration matching
the standard plunger and tie rod configuration, and wherein the
population of in-service pump assemblies further comprises pump
assemblies comprising a standard power end coupled directly to a
standard fluid end.
[0020] Another embodiment provides a method, comprising: (1)
providing a power end comprising a plurality of reciprocatable
drive rods arranged in a first geometric pattern; (2) providing a
fluid end comprising a plurality of plungers arranged in a second
geometric pattern wherein the second geometric pattern is different
from the first geometric pattern; and (3) connecting the power end
to the fluid end via an adaptor comprising an offset coupler to
attach a said drive rod to an offset one of the plungers.
[0021] In an embodiment, the method also includes attaching a said
drive rod to an aligned one of the plungers. In an embodiment, the
method also includes transversely orienting the drive rods and
plungers on opposite sides of a straight line wherein spacing
between the drive rods is different from spacing between the
plungers. In an embodiment, the fluid end comprises a triplex or
quintuplex fluid end assembly, and the method also includes
coupling a middle one of the plungers in alignment with a
corresponding middle one of the drive rods, and connecting side
ones of the plungers with corresponding side ones of the drive rods
at a respective plurality of the offset couplers.
[0022] In an embodiment, the method also includes securing the
power end and the fluid end together by securing opposite ends of a
plurality of tie rods to the power end and the fluid end,
comprising attaching a first tie rod section from the power end to
an offset second tie rod section from the fluid end at an offset
tie rod adapter.
[0023] In an embodiment, the method also includes assembling the
fluid end from a plurality of pump body modules secured together,
for example, securing the pump body modules in a line with
fasteners between opposite end plates.
[0024] In a further embodiment a method comprises: (1) providing a
standby inventory of standard fluid end assemblies comprising a
standard plunger and tie rod configuration; (2) providing a standby
inventory of a plurality of different sets of power end units,
wherein each set of power end units has a different drive rod and
tie rod configuration with respect to the other power end sets,
including at least one set of offset power ends having an offset
drive rod and tie rod configuration with respect to the standard
plunger and tie rod configuration; (3) providing a standby
inventory of adapter units adapted to connect the offset power ends
to the standard fluid ends; (4) connecting a said standard fluid
end, a said adapter unit and a said offset power end from the
standby inventories into a pump assembly; (5) placing a plurality
of the pump assemblies in service; and (6) removing the power end
of one of the in-service pump assemblies for repair or maintenance
and replacing it with a said power end from the standby inventory,
wherein the replacement power end has a different drive rod and tie
rod configuration with respect to the removed power end.
[0025] In an embodiment, the inventory of standard fluid end
assemblies further comprises interchangeable pump body modules,
wherein the fluid end assemblies comprise a plurality of the
modules, and the method also includes removing the standard fluid
end assembly or one or more of the interchangeable pump body
modules for repair or maintenance and replacing it with another one
from the inventory of standard fluid end assembly or one or more of
the interchangeable pump body modules.
[0026] In an embodiment, the inventory of power end units further
comprise a set of standard power ends having a drive rod and tie
rod configuration matching the standard plunger and tie rod
configuration, and the method also includes connecting a said
standard fluid end and a said standard power end from the
respective inventories into a pump assembly.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0027] FIG. 1 is a schematic diagram of a triplex pump assembly
according to an embodiment of the invention.
[0028] FIG. 2 is a schematic diagram of a maintenance inventory
system according to an embodiment.
[0029] FIG. 3 is a schematic diagram of an adaptor module according
to an embodiment.
[0030] FIG. 4 a top plan view of a pump assembly according to an
embodiment.
[0031] FIG. 5 is a sectional view of the pump assembly of FIG. 3 as
seen along the lines 4-4 according to an embodiment.
[0032] FIG. 6 is a side elevation view of the pump assembly of
FIGS. 4-5 according to an embodiment of the invention.
[0033] FIG. 7 is an end view of an offset plunger-drive rod clamp
assembly according to an embodiment.
[0034] FIG. 8 is a top plan view of the clamp of FIG. 7 according
to an embodiment.
[0035] FIG. 9 is a side elevational view of the clamp of FIGS. 7-8
according to an embodiment.
[0036] FIG. 10 is a top plan view of an offset tie rod adaptor
according to an embodiment.
[0037] FIG. 11 is a perspective view of the adaptor of FIG. 10
according to an embodiment.
[0038] FIG. 12 is a top plan view of another offset tie rod adaptor
according to an alternate embodiment.
[0039] FIG. 13 is a perspective view of the adaptor of FIG. 12
according to an embodiment.
[0040] FIG. 14 is a perspective view of a fluid end assembly
according to an embodiment.
[0041] FIG. 15 is an exploded view of the fluid end assembly of
FIG. 14.
DETAILED DESCRIPTION OF THE INVENTION
[0042] With reference to FIG. 1, in an embodiment a pump assembly
100 includes an adaptor 102, comprising a first mechanical
attachment portion 104 for attaching to the drive rods extending
from the power end 106 and a second mechanical attachment portion
108 for attaching to the fluid end modules 110 making up the fluid
end assembly 112. By virtue of the fluid end modules 110 and the
appropriate adaptor 102, the operator and/or assembler has the
ability to create the assembly 100 comprising the adaptor 102, the
fluid end assembly 112, and the power end 106 such that the design
of the fluid end assembly 112 and/or fluid end modules 110 may
remain the same regardless of the type of power end 106 utilized to
form the assembly 100. Such an assembly 100 may be advantageously
cost-effective and allow for greater maintainability of the fluid
end modules 110 and the fluid end assembly 112.
[0043] In one embodiment where the fluid end modules have
substantially identical profiles, i.e., interchangeability of the
fluid end modules 110 in the various fluid end assemblies 112, the
modules 110 may be advantageously interchanged between the middle
and sides in the fluid end assemblies 112, providing advantages in
assembly, disassembly, and maintenance. In operation, if one of the
pump body modules 110 fails, only the failed one of the modules 110
need be replaced, reducing the potential overall downtime of a
fluid end assembly 112. In one embodiment, the pump body modules
110 are smaller than a typical monoblock fluid end having a single
body with a plurality of cylinder bores machined therein, and
therefore provide greater ease of manufacturability due to the
reduced size of forging, castings, etc.
[0044] The adaptor 102 advantageously allows an operator and/or
assembler to orient the fluid end modules 110 for attachment to the
power end 106, regardless of the type of power end 106, e.g., power
ends from different manufacturers and/or different models of power
ends from the same manufacturer. If necessary, the adaptor 102 can
allow for multi-axis adjustments for attaching the fluid end
modules 110 to the power end 106. The adaptor 102, therefore, may
allow the operator and/or assembler to make both lateral and
longitudinal spacing adjustments between the plungers of the fluid
end modules 110 and the drive rods of the power end 106 to account
for relative spacing and alignment adjustments as well as to allow
for adjustments in the stroke of the drive rods and pump
plungers.
[0045] The adaptor 102 allows the use of relatively small
inventories of fluid end modules 110 and/or fluid end assemblies
112 for attachment to a variety of power ends 106. With reference
to FIG. 2, an inventory system for the assembly and/or maintenance
of a population of operating pump assemblies may include an
inventory 120 of a limited number of standardized fluid end
modules, as well as other fluid end components and parts, used to
assemble an inventory 122 of standardized fluid ends having the
same general specifications as well as piston and tie rod
configurations.
[0046] On the other hand, an inventory of power ends 124 can
include offset power ends 126, as well as standard power ends 128,
i.e., power ends having a drive rod and tie rod configuration
compatible with that of the standard fluid ends in the inventory
122. The offset power ends 126, which have a different drive rod
and/or tie rod configuration, with respect to the standard fluid
ends in the inventory 122, may be made by a different manufacturer
or may be a different model from the same manufacturer of the
standard power ends 128. This allows the operator and/or assembler
to obtain power ends that may be more readily available, lower
cost, or more suited to the power requirements in the given
application.
[0047] By maintaining a suitable adaptor inventory 130, including a
set specific for each type of offset power end 126 that may be
present in the inventory 124, the offset power ends 126 can be used
with the appropriate adaptor in any one of the population 132 of
the operating pump assemblies. The standard power ends 128 can be
used in the population 134 of the operating pump assemblies by
direct connection without one of the adaptors 130, or one of the
adaptors 130 can optionally be used as a spacer element. In one
embodiment, where more than one type of standard fluid end is used,
e.g., triplex and quintuplex, the adaptor inventory 108 can include
a set of adaptors specific to each type of fluid end in the
inventory 122 and/or population 132; and additionally or
alternatively, the different types of fluid ends may all have the
same plunger and tie rod configuration throughout, e.g., where more
than one type of fluid end module is used.
[0048] FIGS. 4-6 illustrate a pump assembly 200 incorporating a
standard triplex fluid end 202 and a non-standard or offset power
end 204, according to one embodiment. The fluid end 202 comprises
three interchangeable fluid end modules 206 which have a respective
plunger 208 with a standard spacing in a line, and attachment
flange 210 with a standard configuration for tie rods 212. The
power end 204 has a middle drive rod 214A and side drive rods 214B,
as well as a configuration for tie rods 216, that may or may not
match the configuration for the fluid end plungers 208 and/or tie
rods 212, in whole or in part.
[0049] An adaptor module in the particular example of this
embodiment shown in FIGS. 4-6 includes a standard aligned
plunger-drive rod clamp 218 for the middle drive rod 214A and the
middle one of the plungers 208, and offset plunger-drive rod clamps
220 to connect the side drive rods 214B to the side ones of the
plungers 208. In general, it is preferred to align one of the drive
rods 214A, 214B with one of the plungers 208, preferably the middle
drive rod 214A, to avoid space issues for the offset clamps 220
where the adjacent drive rods 214, 214B may not provide sufficient
room for the use of adjacent offset clamps 220. The combination of
the standard clamp 218 and the particular offset clamps 220 may be
specific to each type of power end 204, depending on the
plunger-drive rod offset distance and direction, and these may be
inventoried separately as components, or alternatively and/or
additionally as prepacked kits or packages comprising one, a
plurality or all of the clamps 218, 220 required for assembly of a
particular combination of power end 204 and fluid end assembly
202.
[0050] The adaptor module may also include offset bolt adaptors 222
as required for the offset tie rods 216. In general, the fluid end
assembly 202 should have one or more tie rods 212 that align with
the tie rod configuration for the offset power end 204, although it
is possible that none or all of tie rods 212, 216 will align for
which the offset bolt adaptors 222 are not required. As with the
plunger clamps 218, 220, the offset bolt adaptors 222 and tie rods
212, 216 of the appropriate number, diameter, thread pitch, length,
etc. may be inventoried separately and/or as part of a kit labeled
for the particular combination of power end 204 and fluid end
assembly 202.
[0051] FIG. 3 illustrates one embodiment of a prepackaged adaptor
module 230 which can be populated with the required number and type
of offset drive rod-plunger clamps 232, standard clamps 234, bolt
adaptors 236, tie rods 238, and so on, for a particular power
end-fluid end assembly. The module 230 can be inventoried
separately, or additionally or alternatively paired with the
appropriate power end. Additionally or alternatively a module 230
can include additional components 232, 234, 236, 238 necessary for
connecting a plurality of some or all of the different types of
power ends or in different configurations or types of
configurations so that the number of adaptor modules kept in
inventory is minimized. Additionally the adaptor modules may
include spare or extra components 232, 234, 236, 238 for the
assembly, and may include any other parts frequently or
occasionally used in making a fluid pump assembly.
[0052] FIGS. 7-9 show an embodiment of an offset plunger-drive rod
clamp 220 having a housing comprised of two split sections 222A,
222B, bolts 224 and alignment pins 226. In this example, openings
228A, 228B and recesses 230A, 230B are provided and formed in the
assembled sections 222A, 222B appropriately offset to receive a
shaft and end or flange of the respective power end drive rod and
fluid end plunger.
[0053] To assemble the clamp 220, after installing the fluid end
and power end, the plunger and drive rod ends are brought together
in the appropriate offset and the clamp sections 222A, 222B are
brought together around the plunger/drive rod ends, using the pins
226 for alignment, and the bolts 224 are secured in place. In this
embodiment, the clamp section 222A has an enlarged through bore 232
and the clamp section has a threaded bore 234 to engage threads on
the bolt 224 which draws the cap 236 tightly against the recessed
surface 238 to secure the clamp sections 222A, 222B together,
holding the opposing ends of the plunger and drive rod in the
appropriate offset alignment. The particular clamp illustrated is
merely for purposes of non-limiting example and other suitable
clamping arrangements will occur to those skilled in the art.
[0054] FIGS. 10-11 illustrate an embodiment of an offset bolt
adaptor 250 which can be used to connect offset tie rods between
the power end and the fluid end. The adaptor 250 is a block having
a pair of threaded bores 252A, 252B to receive the proximal ends of
offset tie rod sections having their opposite ends secured to the
power end and the fluid end assembly. The offset of the bores 252A,
252B matches the offset between the configuration of the tie rod
sections. If desired, the end faces 254A, 254B through which the
bores 252A, 252B are formed may be transversely oriented with
respect to a plane that is at a right angle to the bores.
[0055] FIGS. 12-13 illustrate another embodiment of an offset bolt
adaptor in the form of a block 260 comprised of two split sections
262A, 262B. The block 260 is generally rectangular on all sides.
Each section 262A, 262B has threaded bores 264A, 264B to threadedly
receive the tie rods 266A, 266B and enlarged through bores 268A,
268B to slideably receive the tie rods 266A, 266B. The threaded
bore 264A is aligned with through bore 268B, and the threaded bore
264B with through bore 268A. To compensate for the bending moment
due to the lateral offset of the tie rods 266A, 266B, opposing
surfaces 270A, 270B at which the two sections 262A, 262B are in
abutment, may be transversely oriented with respect to a plane that
is at a right angle to the bores. The tie rods 266A, 266B can be
secured by nuts 272A, 272B opposite the through bores 268A,
268B.
[0056] FIG. 14-15 show a modular fluid end assembly 300 for a
multiplex pump including a plurality of fluid end modules 302
secured between end plates 304 by means of fasteners 306. The end
plates 304 are utilized in conjunction with the fasteners 306 to
assemble the pump bodies 302 to form the fluid end assembly 300.
When the fluid end 300 is assembled, the three pump modules 302 are
assembled together using, for example, four large fasteners or tie
rods 306 and the end plates 304 on opposing ends of the pump
modules 302. At least one of the tie rods 306 may extend through
the pump modules 302, while the other of the tie rods 306 may be
external of the pump modules 302. In addition to the triplex
configuration of fluid end assembly 300, those skilled in the art
will appreciate that the pump modules 302 may also be arranged in
other configurations, such as a quintuplex pump assembly comprising
five pump modules 302, or the like
[0057] Each pump module 302 has an internal passage or bore to
receive a pump plunger 308 through the fluid end connection block
310, which provides a flange for guiding and attaching the pistons
in the pump modules 302 to the drive rods of the power end and
ultimately to a prime mover, such as a diesel engine or the like,
as will be appreciated by those skilled in the art.
[0058] The pump modules 302 may further define inlet and outlet
ports which may be substantially perpendicular to the piston bore
in a crossbore arrangement, i.e., pump modules 302 may define
substantially similar internal geometry as prior art monoblock
fluid ends to provide similar volumetric performance. Those skilled
in the art will appreciate that the internals of the pump modules
302 may comprise bores formed in other configurations such as a
T-shape, Y-shape, in-line, or other configurations.
[0059] In one embodiment, a raised surface 312 extends from an
exterior surface 314 of the pump modules 302, best seen in FIG. 15.
The raised surface 312 may extend a predetermined distance from the
exterior surface 314 and may define a predetermined area on the
exterior surface 314. While illustrated as circular in shape, the
raised surface 312 may be formed in any suitable shape. The end
plates 304 may further comprise a raised surface 316, similar to
the surface 312 on the pump modules 302 for engaging with the
raised surfaces 312 during assembly.
[0060] The tie rods or fasteners 306 may be tightened utilizing a
hydraulic tensioner, as will be appreciated by those skilled in the
art. The tensioner may have its hydraulic power provided by the
outlet flow of the pump assembly 300 itself. The hydraulic
tensioner may provide a constant tension or a variable tension on
the tie rods 306, depending on the requirements of the operation of
the assembly 300. As the tie rods 306 are tightened, via threaded
nuts 318 or the like, to assemble the fluid end 300, the raised
surfaces 312, 316 engage with one another to provide a
pre-compressive force to the areas adjacent the intersection of the
internal bores. The pre-compressive force may counteract the
potential deformation of the areas adjacent the intersection of the
internal bores due to the operational pressure. By counteracting
the potential deformation due to operational pressure, stress on
the adjacent areas is reduced, thereby increasing the overall life
of the pump bodies by reducing the likelihood of fatigue
failures.
[0061] Due to the substantially identical profiles of the plurality
of fluid end modules 302, the fluid end modules 302 may be
advantageously interchanged between the middle and side pump bodies
of the fluid end assembly, providing advantages in assembly,
disassembly, and maintenance, as will be appreciated by those
skilled in the art. In operation, if one of the fluid end modules
302 of the fluid end assembly 300 fails, only the failed one of the
fluid end modules 302 need be replaced, reducing the potential
overall downtime of the fluid end assembly 300 and its associated
monetary impact. The fluid end modules 302 are smaller than a
typical monoblock fluid end having a single body with a plurality
of cylinder bores machined therein and therefore provide greater
ease of manufacturability due to the reduced size of forging,
castings, etc.
[0062] While illustrated as comprising three of the fluid end
modules 302, the fluid end assembly 300 may be formed in different
configurations, such as by separating or segmenting each of the
fluid end modules 302 further, by segmenting each of the fluid end
modules 302 in equal halves along an axis that is substantially
perpendicular to the surfaces 314, or by any suitable
segmentation.
[0063] The fluid end modules 302 may be further pre-compressed in
another additional or alternative embodiment in order to counteract
the potential deformation of internal areas, by expanding one or
more displacement plugs 320 disposed at predetermined locations
within the fluid end modules 302. The plugs 320 are placed in, for
example, a drilled bore or cavity formed in the fluid end modules
302 and expanded with the use of an expansion tool and/or
application of a radial force to the drilled bore or cavity, as
will be appreciated by those skilled in the art. The bore formed in
the fluid end modules 302 may be cylindrical for a cylindrical plug
320, or tapered to accommodate a tapered plug 320 therein.
[0064] The expansion of the displacement plug 320 by application of
a radial force induces a radial plastic yielding of the plug 320
and an elastic radial deformation of the surrounding material of
the fluid end modules 302. When the radial force is removed in one
embodiment, the plug 320 contracts slightly radially inward due
elastic relaxation; however, the radial deformation of the
surrounding material of the fluid end modules 302 does not
completely vanish following the relaxation because the elastic
radial deformation of the fluid end modules 302 is larger than the
plastic radial deformation of the plug 320. As a result, there is a
remaining stress between the plug 320 and the fluid end module 302
after relaxation.
[0065] The pre-compressive force in an embodiment may also be
hydraulically or pneumatically applied pressure, for example, via
suitable sealed hydraulic or pneumatic connections to the cavity.
The pre-compressive force in an embodiment may be applied by
injecting a liquid or semi-liquid material into the bore that
expands as it solidifies, the expansion of the material providing
the pre-compressive force. In another embodiment where the plug 320
is permanently expanded or otherwise larger than the cavity in
which it is received in the fluid end modules 302, the plug 320
displaces the area around the plug, maintaining stress against the
abutting surface of the cavity.
[0066] Accordingly, the invention provides the following
embodiments:
A. A pump assembly, comprising: a power end comprising a plurality
of reciprocatable drive rods arranged in a first geometric pattern;
a fluid end comprising a plurality of plungers arranged in a second
geometric pattern wherein the second geometric pattern is different
from the first geometric pattern; and an adaptor to connect the
power end to the fluid end, wherein the adaptor comprises an offset
coupler to attach a said drive rod to an offset one of the
plungers. B. The pump assembly of embodiment A wherein the adaptor
further comprises an in-line coupler to attach a said drive rod to
an aligned one of the plungers. C. The pump assembly of embodiment
A or embodiment B wherein the first and second geometric patterns
comprise a straight line, wherein the drive rods and plungers are
transversely oriented on opposite sides of the line, and wherein a
spacing between the drive rods is different from a spacing between
the plungers. D. The pump assembly of any one of embodiments A to
C, comprising a triplex or quintuplex fluid end wherein a middle
one of the plungers is coupled in alignment with a corresponding
middle one of the drive rods, and wherein side ones of the plungers
are connected with corresponding side ones of the drive rods using
a respective plurality of the offset couplers. E. The pump assembly
of any one of embodiments A to D wherein the offset coupler
comprises an eccentric clamp. F. The pump assembly of embodiment E
wherein the eccentric clamp comprises a split housing halves, a
first opening and recess to receive the drive rod and an enlarged
end thereof, a second opening and recess to receive the plunger and
an enlarged end thereof, and a plurality of bolts to removable
secure the housing halves. G. The pump assembly of any one of
embodiments A to F wherein the adaptor further comprises a
plurality of tie rods secured at opposite ends to the power end and
the fluid end, wherein at least one of the tie rods includes an
offset tie rod adapter to attach a first tie rod section from the
power end with an offset second tie rod section from the fluid end.
H. The pump assembly of embodiment G wherein the offset tie rod
adaptor comprises opposing first and second elongated blocks
abutting at a sloping transverse surface, a through bore and a
threaded bore formed in each of the first and second blocks,
wherein the through bores of the first and second blocks are
aligned at the transverse surface with the threaded bores of the
respective second and first blocks, wherein the through bores are
formed longitudinally in a portion of the blocks that is longer
than a portion of the blocks in wherein the threaded bores are
formed, wherein the first tie rod section is slideably received in
the through bore of the first block and threadedly engaged in the
threaded bore of the second block and wherein the second tie rod
section is slideably received in the through bore of the second
block and threadedly engaged in the threaded bore of the first
block. I. The pump assembly of any one of embodiments A to H
wherein the fluid end comprises a plurality of pump body modules
secured together to form the fluid end. J. The pump assembly of
embodiment I wherein the pump body modules are secured in a line
with fasteners between opposite end plates. K. A pump assembly and
maintenance system, comprising: (a) a standby inventory of standard
fluid end assemblies comprising a standard plunger and tie rod
configuration; (b) a standby inventory of a plurality of different
sets of power end units, wherein each set of power end units has a
different drive rod and tie rod configuration with respect to the
other power end sets, including at least one set of offset power
ends having an offset drive rod and tie rod configuration with
respect to the standard plunger and tie rod configuration; (c) a
standby inventory of adapter units to connect the offset power ends
to the standard fluid ends; and (d) a population of pump assemblies
in service, comprising in-service pump assemblies comprising a said
standard fluid end, a said adapter unit and a said offset power
end, whereby the in-service pump assemblies can be repaired by
removing the power end and replacing with a said power end from the
standby inventory thereof wherein the replacement power end has a
different drive rod and tie rod configuration with respect to the
removed power end. L. The pump assembly and maintenance system of
embodiment K wherein the inventory of power end units further
comprise a set of standard power ends having a drive rod and tie
rod configuration matching the standard plunger and tie rod
configuration, and wherein the population of in-service pump
assemblies further comprises pump assemblies comprising a standard
power end coupled directly to a standard fluid end. M. The pump
assembly and maintenance system of embodiment K or embodiment L
wherein the inventory of standard fluid end assemblies further
comprises interchangeable pump body modules, wherein the fluid end
assemblies comprise a plurality of the modules, whereby the
in-service pump assemblies can be repaired by removing and
replacing the standard fluid end assembly or one or more of the
interchangeable pump body modules. N. A method, comprising: (a)
providing a power end comprising a plurality of reciprocatable
drive rods arranged in a first geometric pattern; (b) providing a
fluid end comprising a plurality of plungers arranged in a second
geometric pattern wherein the second geometric pattern is different
from the first geometric pattern; and (c) connecting the power end
to the fluid end via an adaptor comprising an offset coupler to
attach a said drive rod to an offset one of the plungers. O. The
method of embodiment N, further comprising attaching a said drive
rod to an aligned one of the plungers. P. The method of embodiment
N or embodiment 0, further comprising transversely orienting the
drive rods and plungers on opposite sides of a straight line
wherein spacing between the drive rods is different from spacing
between the plungers. Q. The method of any one of embodiments N to
P, wherein the fluid end comprises a triplex or quintuplex fluid
end assembly, and further comprising coupling a middle one of the
plungers in alignment with a corresponding middle one of the drive
rods, and connecting side ones of the plungers with corresponding
side ones of the drive rods at a respective plurality of the offset
couplers. R. The method of any one of embodiments N to Q further
comprising securing the power end and the fluid end together by
securing opposite ends of a plurality of tie rods to the power end
and the fluid end, comprising attaching a first tie rod section
from the power end to an offset second tie rod section from the
fluid end at an offset tie rod adapter. S. The method of any one of
embodiments N to R comprising assembling the fluid end from a
plurality of pump body modules secured together. T. The method of
embodiment S comprising securing the pump body modules in a line
with fasteners between opposite end plates. U. A method,
comprising: (a) providing a standby inventory of standard fluid end
assemblies comprising a standard plunger and tie rod configuration;
(b) providing a standby inventory of a plurality of different sets
of power end units, wherein each set of power end units has a
different drive rod and tie rod configuration with respect to the
other power end sets, including at least one set of offset power
ends having an offset drive rod and tie rod configuration with
respect to the standard plunger and tie rod configuration; (c)
providing a standby inventory of adapter units adapted to connect
the offset power ends to the standard fluid ends; (d) connecting a
said standard fluid end, a said adapter unit and a said offset
power end from the standby inventories into a pump assembly; (e)
placing a plurality of the pump assemblies in service; and (f)
removing the power end of one of the in-service pump assemblies for
repair or maintenance and replacing it with a said power end from
the standby inventory, wherein the replacement power end has a
different drive rod and tie rod configuration with respect to the
removed power end. V. The method of embodiment U wherein the
inventory of standard fluid end assemblies further comprises
interchangeable pump body modules, wherein the fluid end assemblies
comprise a plurality of the modules, and further comprising
removing the standard fluid end assembly or one or more of the
interchangeable pump body modules for repair or maintenance and
replacing it with another one from the inventory of standard fluid
end assembly or one or more of the interchangeable pump body
modules. W. The method of embodiment U or embodiment V wherein the
inventory of power end units further comprise a set of standard
power ends having a drive rod and tie rod configuration matching
the standard plunger and tie rod configuration, and further
comprising connecting a said standard fluid end and a said standard
power end from the respective inventories into a pump assembly. X.
Any one of the pump assembly of embodiment I or embodiment J, or
the pump assembly and maintenance system of embodiment M, further
comprising raised surfaces on opposite exterior side surfaces of
the pump body modules, wherein the raised surfaces engage with an
adjacent end plate or the raised surface of an adjacent pump body
module, whereby the tightening of the fasteners applies a
pre-compressive force at the raised surfaces on each of the pump
body modules. Y. Any one of embodiment I, embodiment J, embodiment
M, or embodiment X, further comprising an expanded displacement
plug in a cavity formed in the pump body modules, wherein the
expanded displacement plug applies a pre-compressive force at the
cavity on each of the pump body modules.
[0067] The preceding description has been presented with reference
to present embodiments. Persons skilled in the art and technology
to which this disclosure pertains will appreciate that alterations
and changes in the described structures and methods of operation
can be practiced without meaningfully departing from the principle,
and scope of this invention. Accordingly, the foregoing description
should not be read as pertaining only to the precise structures
described and shown in the accompanying drawings, but rather should
be read as consistent with and as support for the following claims,
which are to have their fullest and fairest scope.
* * * * *