U.S. patent application number 15/756654 was filed with the patent office on 2018-09-20 for access pump casing.
The applicant listed for this patent is TSC Manufacturing and Supply, LLC. Invention is credited to Ian HAAS, David KERR.
Application Number | 20180266413 15/756654 |
Document ID | / |
Family ID | 63521173 |
Filed Date | 2018-09-20 |
United States Patent
Application |
20180266413 |
Kind Code |
A1 |
KERR; David ; et
al. |
September 20, 2018 |
ACCESS PUMP CASING
Abstract
A new pump design is described. The pump features a casing with
a continuous enclosure extending from a power end of the casing to
a fluid end of the casing for housing the reciprocating assembly of
the pump, which includes a crankshaft, a plurality of control rods
coupled to the crankshaft, and a plurality of crossheads coupled to
the control rods. A detachable lid is attached to the casing at the
power end and the fluid end of the casing, and encloses the
reciprocating assembly. An alignment plate oriented substantially
parallel to a stroke axis of the pump maintains alignment of the
crossheads.
Inventors: |
KERR; David; (Houston,
TX) ; HAAS; Ian; (Houston, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TSC Manufacturing and Supply, LLC |
Houston |
TX |
US |
|
|
Family ID: |
63521173 |
Appl. No.: |
15/756654 |
Filed: |
April 21, 2016 |
PCT Filed: |
April 21, 2016 |
PCT NO: |
PCT/US16/28538 |
371 Date: |
March 1, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
14841856 |
Sep 1, 2015 |
9702359 |
|
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15756654 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04B 1/16 20130101; F04B
53/22 20130101; F04B 47/02 20130101; F04B 53/006 20130101; F04B
53/16 20130101; F04B 53/144 20130101; F04B 1/0421 20130101 |
International
Class: |
F04B 53/16 20060101
F04B053/16; F04B 1/04 20060101 F04B001/04; F04B 1/16 20060101
F04B001/16; F04B 47/02 20060101 F04B047/02; F04B 53/00 20060101
F04B053/00; F04B 53/14 20060101 F04B053/14 |
Claims
1. A pump, comprising: a reciprocating assembly comprising a
crankshaft, a plurality of control rods coupled to the crankshaft,
and a plurality of crossheads coupled to the control rods, wherein
the stroke of the crossheads define an axis of the pump, and the
crankshaft is disposed transverse to the axis of the pump; a casing
with a continuous enclosure extending from a power end of the
casing to a fluid end of the casing for housing the reciprocating
assembly; and a detachable lid that fastens to the casing at the
power end and at the fluid end.
2. The pump of claim 1, further comprising an alignment plate that
fastens to the casing in an orientation aligned with the axis of
the pump.
3. The pump of claim 2, wherein the lid has a first portion that
covers the crankshaft and a second portion that covers the
crossheads, and the first and second portions are non-coplanar.
4. The pump of claim 3, wherein the first portion and the second
portion of the lid are connected by a third portion that forms an
angle with the first portion and the second portion.
5. The pump of claim 4, wherein the alignment plate has a curved
alignment surface for each crosshead.
6. The pump of claim 5, wherein the pump casing has an alignment
feature opposite each alignment surface of the alignment plate.
7. The pump of claim 6, wherein the alignment plate contacts a
curved surface of the casing.
8. The pump of claim 7, further comprising a seal between the
alignment plate and the casing.
9. The pump of claim 8, wherein the alignment plate has a curved
surface that contacts a flat surface of the casing.
10. A pump, comprising: a reciprocating assembly comprising a
crankshaft, a plurality of control rods coupled to the crankshaft,
and a plurality of crossheads coupled to the control rods, wherein
the stroke of the crossheads define an axis of the pump, and the
crankshaft is disposed substantially perpendicular to the axis of
the pump; a casing with a continuous enclosure extending from a
power end of the casing to a fluid end of the casing for housing
the reciprocating assembly; a detachable lid that fastens to the
casing at the power end and at the fluid end; and an alignment
plate that fastens to the casing in an orientation substantially
parallel to the axis of the pump, wherein the alignment plate has a
curved alignment surface for each crosshead.
11. The pump of claim 10, wherein the pump casing has an alignment
feature opposite each alignment surface of the alignment plate.
12. The pump of claim 11, wherein the alignment plate contacts a
curved surface of the casing.
13. The pump of claim 12, wherein the curved surface of the casing
intersects a stress point of the casing.
14. The pump of claim 13, wherein the casing has an opening through
which the crankshaft is disposed, and the stress point is a span
between an edge of the opening and the curved surface.
15. The pump of claim 14, wherein the casing has two sides
connecting the power end and the fluid end, the attachment plate
fastens to the sides of the casing, and the lid fastens to the
sides of the casing.
16. The pump of claim 10, wherein the lid has a first portion that
covers the crankshaft and a second portion that covers the
crossheads, and the first and second portions are non-coplanar.
17. The pump of claim 16, wherein the first portion and the second
portion of the lid are connected by a third portion that forms an
angle with the first portion and the second portion.
18. A pump, comprising: a reciprocating assembly comprising a
crankshaft, a plurality of control rods coupled to the crankshaft,
and a plurality of crossheads coupled to the control rods, wherein
the stroke of the crossheads define an axis of the pump, and the
crankshaft is disposed substantially perpendicular to the axis of
the pump; a casing with a continuous enclosure extending from a
power end of the casing to a fluid end of the casing for housing
the reciprocating assembly and an alignment feature for each
crosshead; a detachable lid that fastens to the casing at the power
end and at the fluid end; and an alignment plate that fastens to
the casing in an orientation substantially parallel to the axis of
the pump, wherein the alignment plate has a curved alignment
surface for each crosshead opposite each respective alignment
feature of the casing.
19. The pump of claim 18, wherein the casing has two sides
connecting the power end and the fluid end, the attachment plate
fastens to the sides of the casing, and the lid fastens to the
sides of the casing.
20. The pump of claim 19, wherein the alignment plate contacts a
curved surface of the casing located at a stress point of the
casing.
Description
FIELD
[0001] Embodiments described herein relate to pumps for oilfield
applications. More specifically, the embodiments described herein
relate to pump designs having improved access to internal
parts.
BACKGROUND
[0002] Production of oil and gas is a trillion dollar industry.
Producers continually seek ways to increase the speed and
flexibility, and lower the cost of, production apparatus for
onshore and offshore oil and gas production. Equipment downtime is
costly, so efficient repair and replacement of equipment in the
field is valuable.
[0003] Reciprocating pumps are used in the oil industry for many
purposes. In one type of pump, a crankshaft turns inside a casing,
and control rods couple to the crankshaft to drive one or more
crossheads in a reciprocating motion to pump a fluid. In
conventional pump designs, to remove any of the control rods and
crossheads from the pump, the crankshaft must also be removed. This
adds costly time to any repair or maintenance of the control rods
and crossheads. There is a need for a pump design that enables fast
access and servicing of pump components without removing the
crankshaft.
SUMMARY
[0004] Embodiments disclosed herein provide a pump with a
reciprocating assembly comprising a crankshaft, a plurality of
control rods coupled to the crankshaft, and a plurality of
crossheads coupled to the control rods, wherein the stroke of the
crossheads define an axis of the pump, and the crankshaft is
disposed substantially perpendicular to the axis of the pump; a
casing with a continuous enclosure extending from a power end of
the casing to a fluid end of the casing for housing the
reciprocating assembly; and a detachable lid that fastens to the
casing at the power end and at the fluid end.
[0005] Other embodiments described herein provide a pump with a
reciprocating assembly comprising a crankshaft, a plurality of
control rods coupled to the crankshaft, and a plurality of
crossheads coupled to the control rods, wherein the stroke of the
crossheads define an axis of the pump, and the crankshaft is
disposed substantially perpendicular to the axis of the pump; a
casing with a continuous enclosure extending from a power end of
the casing to a fluid end of the casing for housing the
reciprocating assembly; a detachable lid that fastens to the casing
at the power end and at the fluid end; and an alignment plate that
fastens to the casing in an orientation substantially parallel to
the axis of the pump, wherein the alignment plate has a curved
alignment surface for each crosshead.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] So that the manner in which the above-recited features of
the present invention can be understood in detail, a more
particular description of the invention, briefly summarized above,
may be had by reference to embodiments, some of which are
illustrated in the appended drawings. It is to be noted, however,
that the appended drawings illustrate only typical embodiments of
this invention and are therefore not to be considered limiting of
its scope, for the invention may admit to other equally effective
embodiments.
[0007] FIG. 1 is a perspective view of a pump 100 according to one
embodiment.
[0008] FIG. 2 is a perspective view of the pump of FIG. 1 the lid
and end plate separated from the casing.
[0009] FIG. 3 is a side view of the lid.
[0010] FIG. 4 is a side view of an alignment plate according to one
embodiment.
[0011] FIG. 5A is a perspective view of the casing of the pump of
FIG. 1.
[0012] FIGS. 5B and 5C are perspective views of alternate
embodiments of the alignment plate of FIG. 4.
[0013] FIG. 6 is a perspective view of a pump casing according to
another embodiment.
[0014] To facilitate understanding, identical reference numerals
have been used, where possible, to designate identical elements
that are common to the figures. It is contemplated that elements
disclosed in one embodiment may be beneficially utilized on other
embodiments without specific recitation.
DETAILED DESCRIPTION
[0015] FIG. 1 is a perspective view of a pump 100 according to one
embodiment. The pump 100 is a high pressure pump that may be used
for pumping fluids in an oil production operation or an oil and gas
drilling operation. For example, the pump 100 may be used to pump
crude oil or drilling fluids.
[0016] The pump 100 has a power end 102 and a fluid end 104. The
power end 102 features a crankcase 105 in which a crankshaft 106 is
disposed for operation. The crankshaft 106 may be removed from the
crankcase 105 for maintenance. A bearing assembly 108 positions and
controls the crankshaft 106, which protrudes through the bearing
assembly 108 outside the crankcase 105 for power coupling.
[0017] The pump 100 has a casing 110 that partially encloses the
operating components of the pump 100, including the crankshaft 106
and control rods and crossheads shown in other figures and
described below in more detail. The casing extends from the power
end 102 to the fluid end 104, and has a generally rectangular
profile. The casing has a depth d.sub.1 at the power end 102 that
accommodates the crankshaft 106 and transitions to a depth d.sub.2
at the fluid end 104 that accommodates connection to a fluid
coupling (not shown). The depth d.sub.1 is larger than the depth
d.sub.2 in the embodiment of FIG. 1, but is not necessarily so.
[0018] The pump 100 has a detachable lid 112 that covers and
encloses the operating components of the pump 100. The detachable
lid 112 fastens to the casing 110 at the power end 102 and near the
fluid end 104, and along the sides 113 of the lid 112. The lid 112
has an angled portion 114 that connects a first portion 116 of the
lid that encloses the crankcase 105 with a second portion 118 of
the lid that attaches to the casing 110 near the fluid end 104,
such that the first portion 116 and the second portion 118 are
non-coplanar. The second portion 118 may be a flange that provides
only connection to the casing 110 at the fluid end, or the second
portion 118 may be a cover portion that encloses the stroke area of
the crossheads, depending on the extent of the second portion 118.
The pump 100 has optional mounts 120 that may be used to affix or
secure the pump 100 to another support. An end plate 122 provides
access to the operating cavity of the pump 100 through the casing
110 at the power end 102.
[0019] FIG. 2 is a perspective view of the pump 100 with the lid
112 and end plate 122 separated from the casing 110. The crankshaft
106 is visible inside the crankcase 105. The casing 110 defines a
continuous operating cavity 200 that extends from the power end 102
to the fluid end 104, with no dividers positioned in the operating
cavity 200. Control rods 202 are shown coupled to the crankshaft
106, and crossheads 204 are shown coupled to the control rods 202.
The detachable lid 112 may be removed from the casing 110 to
provide access to the control rods 202 and crossheads 204 so the
control rods 202 and crossheads 204 may be removed or otherwise
manipulated without removing the crankshaft 106 from the crankcase
105. This capability simplifies pump maintenance and repair.
[0020] The crankshaft 106, control rods 202, and crossheads 204
together define a reciprocating assembly 208 that is housed in the
operating cavity 200. When the lid 112 is fastened in place, the
operating cavity 200 is a continuous enclosure from the end plate
122 to the fluid end 104, with no walls, partitions, or dividers in
the operating cavity 200. The stroke of the crossheads 204 defines
an axis 205 of the pump parallel to the stroke of the crossheads
204. Each of the crossheads 204 travels along a stroke axis 207
aligned with the axis of the pump, and the crankshaft 106 is
disposed transverse to the axis 205 of the pump. Alignment of the
crossheads 204 is maintained by an alignment plate 210 that is
fastened to the casing 110 in an orientation aligned with the axis
205 of the pump. A major axis 211 of the alignment plate 210 is
oriented transverse to the axis 205 of the pump when the alignment
plate 210 is installed, and the alignment plate 210 fastens to the
sides of the pump casing 110 at a notch 212 in the sides of the
pump casing 110. The notch 212 positions the alignment plate 210
such that alignment surfaces 214 of the alignment plate 210 are in
close proximity to the crossheads 204 during operation.
[0021] The lid 112 is fastened to the casing 110 at the power end
102, at the fluid end 104, and at the sides 215 of the casing 110.
Two fastening points 216 adjacent to the notch 212, on either side
thereof, fasten the lid 112 to the side of the casing 110. A pair
of such fastening points 216 are on each side of the casing 110.
The lid 112 has two fastening points 218 at the power end 102 of
the pump 100 and two fastening points 220 at the fluid end 104 of
the pump. The fastening points 218 are located near the sides 113
of the lid 112 at the power end corners 222 of the lid 112. The
fastening points 220 at the fluid end 104 of the pump are spaced
apart from the fluid end corners 224 of the lid 112, and are
located near a center line 226 of the lid 112. In the embodiment of
FIG. 2.
[0022] The pump 100 is shown with three control rod/crosshead pairs
coupled to three cycle points of the crankshaft 106, buy any number
of pairs may be used with appropriate enhancement of the crankshaft
106. The stroke axis 207 of each control rod/crosshead pair extends
substantially through the center of each crosshead 204. The stroke
axis 207 of an outermost control rod/crosshead pair 226 is disposed
between a fastening point 218 and a corresponding fastening point
220. The fastening point 218 and the fastening point 220 are on
opposite sides of a plane defined by the stroke axis 207 of the
outermost control rod/crosshead pair 226. The fastening points 218
and fastening points 220 are in the same geometric relationship
with respect to the outermost control rod/crosshead pair 226 on
either side of the pump 100.
[0023] Placement of the fastening points 218 and 220 in this
relationship reduces twisting of the pump casing 110 and separation
of the lid 112 from the casing 110 as stresses produced by stroking
the crossheads 204 propagate through the pump 100. Each power
stroke produces a downward thrust on the casing 110, which may be
off-axis with respect to the pump casing 110. The off-axis power
stroke causes a torque on the pump casing 110 that would engender
separation of the lid 112 from the casing 110 but for the fasteners
fastening the lid 112 to the casing 110 at the sides.
[0024] The alignment plate 210 has a flange 230 that fastens to the
sides of the pump casing 110. The flange 230 has a thickness that
substantially fills the notch 212 and provides a surface continuity
with the portions of the pump casing 110 on either side of the
notch, thus providing a flat surface for mating with the lid 112.
Referring back to FIG. 1, the flange 230 of the alignment plate 210
is shown with a top surface 231 aligned with a top surface 232 of
the casing 110 adjacent to the notch 212. The aligned surfaces 231
and 232 provide a flat surface for mating with the lid 112. If
desired, a seal member may be disposed in a surface of the lid 112
for sealing against the surfaces 231 and 232 on either side of the
pump 100. Additionally, the surfaces 231 and 232 may be uneven, and
the lid 112 may be contoured at the sides 113 of the lid to follow
and abut the surfaces 231 and 232.
[0025] FIG. 3 is a side view of the lid 112 according to one
embodiment. The lid 112 has a corner section 302 that follows
contours in the casing 110 (FIG. 1). A first corner 304 follows a
transition in the casing 110 from the crankcase 105 to a
mid-section of the casing 110 proximate to the control rods 202
(FIG. 2). A vertical surface 306 mates with a vertical surface of
the crankcase 105. A second corner 308 mates with a corner where
the vertical surface of the crankcase 105 meets the top surface 231
of the alignment plate 210, when the alignment plate 210 is
installed in the notch 212. A lower surface 310 of the lid abuts
the surfaces 231 and 232 of the alignment plate 210 and the casing
110. An upper abutment 312 of the lid abuts the portion of the
casing 110 above the crankcase 105. The upper abutment 312, the
vertical surface 306, and the lower surface 310 together press
against the casing 110 to seal the operating cavity 200 against
leakage.
[0026] The lid 112 has a bevel 314 that matches a corresponding
bevel in the casing 110 at the power end 102 of the pump 100. The
fastening points 218 are provided with fastening tabs 316 for
convenient seating and optimal positioning of fasteners. Fastening
tabs 318 are also provided for optimal positioning of fasteners to
engage the fastening points 216 of the casing 110.
[0027] FIG. 4 is an end view of the alignment plate 210 viewed from
the fluid end. The flange 230 and the alignment features 214 are
visible. Strength features 402 may be included in the alignment
plate to provide additional strength to the entire pump structure
during operation. The strength features 402 may include a
transverse strength feature 404 and an axial strength feature 406
to provide enhanced strength along two axes. The alignment plate
210 has a thickness selected to provide a minimum strength at the
thinnest parts of the plate 210. For example, at an apex 408 of
each alignment feature 214, the thickness of the alignment plate
210 is at least about 100 mils.
[0028] The alignment plate 210 has a flat portion 410 between each
alignment feature 214. The flat portion 410 results from the
process of forming the alignment features 214. In one embodiment, a
precursor to the alignment plate 214, which is a plate with a flat
bottom, is attached to the pump casing 110. With the end plate 122
removed, a bore is then performed through the power end of the
casing 110 to bore the alignment features 214 into the precursor
plate to form the alignment plate 214. The bore process leaves the
flat portions 410 between the alignment features 214. It should be
noted that in some embodiments the flat portions 410 may be
processed following the bore process to round or smooth the edges
of the flat portions 410.
[0029] The alignment features 214 of the alignment plate 210 may be
coated with a lubricant coating, such as Teflon, if desired. The
alignment features 214 may also have a surface treatment, applied
following the bore process described above, to increase smoothness
of the alignment features.
[0030] FIG. 5A is a perspective view of the casing 110 according to
one embodiment. The casing 110 may have a curved surface 502 at a
stress point 504. The casing 110 has an opening 506 through which
the crankshaft 106 is disposed, and the stress point 504 is at a
span 505 between the opening 506 and the curved surface 502. The
curved surface 502 is provided to minimize the possibility of
stress cracking due to cyclical stresses from the reciprocating
assembly.
[0031] The curvature of the curved surface 502 is selected to
provide stress reduction at the stress point 504 while maintaining
the capability to seal the operating cavity 200. A minimum
curvature is typically needed to ensure acceptable life of the
casing 110. The minimum curvature depends on dimension of the span
and thickness of the side of the casing 110. The size of the span
505 will scale with the size and power of the pump 100. In one
embodiment the span will be from about 1 inch to about 2 inches,
for example about 1.5 inches. The curvature of the curved surface
505 may be defined by a radius of curvature. In one embodiment, the
radius of curvature of the curved surface 505 is from about 0
inches, in other words limited only by the tool used to make the
curved surface, to about 0.75 inches, for example about 0.5
inches.
[0032] As noted above in connection with FIG. 2, the curved surface
502 defines a portion of the notch 212, in which the alignment
plate 210 is fastened. The alignment plate 210 may have a curved
portion 506 of the flange 230 for mating with the curved surface
502 of the notch 212, as shown in FIG. 5B, which is a perspective
view of an alternate embodiment of the alignment plate 210. For
ease of machining, the alignment plate 210 may alternately have a
beveled portion 508 of the flange 230 for mating with the curved
surface 502 of the notch 212, as shown in FIG. 5C, which is a
perspective view of another alternate embodiment of the alignment
plate 210. In the event a beveled alignment plate is used, a seal
may be disposed between the beveled portion 508 and the curved
surface 502 for sealing the opening between the two features. The
seal may be pressure fit or adhesive bonded in the opening. The
seal is typically a compliant material to maintain a seal under
cyclical loading.
[0033] The casing 110 has alignment features 510 in a bottom wall
512 of the casing 110. The alignment features 510 cooperate with
the alignment features 214 of the alignment plate 210 to maintain
alignment of the crossheads 202 during operation. The alignment
features 510 may be made in a way similar to the way the alignment
features 214 are made. A precursor casing lacking the alignment
features 510 may have the precursor plate to the alignment plate
installed, and a bore process may be performed through the power
end 102 of the casing 110. The bore process cuts through a portion
of the bottom wall 512 and the alignment plate 210 to form the
alignment features 214 and 510. As with the alignment features 214,
the alignment features 510 may be coated with a lubricant coating,
such as Teflon, or may have a surface treatment to increase
smoothness. The sides 113 of the casing 110 may also have alignment
features 514 formed in the same bore process.
[0034] The pump 100 provides improved access to the operating
cavity 200 through use of a detachable lid 112. The operating
cavity 200 is a continuous cavity, with no walls or dividers, and
alignment of the crossheads 202 is maintained using an alignment
plate 210 with alignment features 214, optionally in addition to
alignment features 510, 514 in the bottom and sidewalls of the
casing 110. Such features allow rapid maintenance and parts
replacement without the need to remove the entire reciprocating
assembly from the pump 100.
[0035] FIG. 6 is a perspective view of a pump casing 600 according
to another embodiment. FIG. 6 omits internal components of the pump
itself for simplicity. Similar to the other embodiments described
herein, the pump casing 600 has a power end 602 and a fluid end
604. An alignment plate 606 of the pump casing 600 differs from the
alignment plate 210 mainly in being located entirely internal to
the pump casing 600. Where the alignment plate 210 fastens to the
sides of the pump casing 110 at the notch 212, the alignment plate
606 is fastened to ledges 610 the project from the sides of the
pump casing 600 toward the interior of the pump casing 600. As
shown in FIG. 6, the sides of the alignment plate 606 are fastened
to the ledges 610. Additionally, the side of the alignment plate
606 facing the fluid end 604 features tabs 614 that are fastened to
mounts 612 at a wall of the pump casing 600 between the power end
602 and the fluid end 604. A lid 616 encloses the pump casing 600
by fastening to the sides of the pump casing 600. The embodiment of
FIG. 6 provides similar cross-head alignment benefits without the
need to provide a seal between the alignment plate 606 and the
sides of the pump casing 600.
[0036] While the foregoing is directed to embodiments of the
invention, other and further embodiments of the invention may be
devised without departing from the basic scope thereof.
* * * * *