U.S. patent application number 10/441159 was filed with the patent office on 2004-11-25 for fluid end assembly.
Invention is credited to Vicars, Berton L..
Application Number | 20040234404 10/441159 |
Document ID | / |
Family ID | 33449944 |
Filed Date | 2004-11-25 |
United States Patent
Application |
20040234404 |
Kind Code |
A1 |
Vicars, Berton L. |
November 25, 2004 |
Fluid end assembly
Abstract
A fluid end for a high-pressure pump. The fluid end includes a
pump housing having a plunger bore within which is positioned a
reciprocating plunger. Extending upwardly at an incline from the
inner end of the plunger bore is a discharge passage. Extending
downwardly at an incline from the inner end of the plunger bore is
a suction passage. Discharge and suction valves are secured,
respectively, within the discharge and suction passages.
Inventors: |
Vicars, Berton L.; (Odessa,
TX) |
Correspondence
Address: |
James B. Conte
Barnes & Thornburg
P.O. Box 2786
Chicago
IL
60690-2786
US
|
Family ID: |
33449944 |
Appl. No.: |
10/441159 |
Filed: |
May 20, 2003 |
Current U.S.
Class: |
417/571 |
Current CPC
Class: |
F04B 53/102 20130101;
F04B 53/16 20130101; F04B 53/22 20130101 |
Class at
Publication: |
417/571 |
International
Class: |
F04B 053/10 |
Claims
I claim:
1. A pump housing for a fluid end assembly, comprising: a metal
forging having: a plunger bore for receiving a reciprocating
plunger, said plunger bore being oriented along a first centerline
and having a closed inner end and an open outer end; a suction
passage intersecting said plunger bore for receiving a suction
valve, said suction passage being oriented along a second
centerline that is coplanar with said first centerline and that
intersects said first centerline at a first reference point so as
to define a first obtuse angle; a discharge passage intersecting
both said plunger bore and said suction passage for receiving a
discharge valve, said discharge passage being oriented along a
third centerline that is coplanar with said second centerline and
said first centerline and that intersects said first centerline at
a second reference point that is closer to said open outer end than
said first reference point so as to define a second obtuse angle;
and, an outlet passage intersecting said discharge passage
substantially at right angles.
2. The pump housing for a fluid end assembly according to claim 1
wherein said suction passage and said discharge passage are each
provided with portions of reduced diameter that define
valve-supporting decks at their tops.
3. The pump housing for a fluid end assembly according to claim 1
wherein said discharge passage has a diameter that is greater than
that of said suction passage so that, when servicing is required,
the suction valve can be removed from said pump housing through
said discharge passage.
4. The pump housing for a fluid end assembly according to claim 1
wherein said first obtuse angle measures about 125.degree. and said
second obtuse angle measures about 115.degree..
5. A fluid end assembly, comprising: a pump housing with: a plunger
bore being oriented along a first centerline and having a closed
inner end and an open outer end; a suction passage intersecting
said plunger bore and being oriented along a second centerline that
is coplanar with said first centerline, said suction passage
intersecting said first centerline at a first reference point so as
to define a first obtuse angle; a discharge passage intersecting
both said plunger bore and said suction passage, said discharge
passage being oriented along a third centerline that is coplanar
with said second centerline and said first centerline and that
intersects said first centerline at a second reference point that
is closer to said open outer end than said first reference point so
as to define a second obtuse angle; an outlet passage intersecting
said discharge passage substantially at right angles; a
reciprocating plunger being located in said plunger bore; a suction
valve being located in said suction passage; a discharge valve
being located in said discharge passage; and, a fluid supply
manifold secured to said pump housing and being in fluid
communication with said suction passage.
6. The fluid end assembly according to claim 5 wherein said suction
passage and said discharge passage are each provided with portions
of reduced diameter that define a pair of decks for supporting,
respectively, said suction-valve and said discharge valve within
said suction passage and said discharge passage.
7. The fluid end assembly according to claim 5 wherein said
discharge passage has a diameter that is greater than that of said
suction passage so that, when servicing is required, the suction
valve can be removed from said pump housing through said discharge
passage.
8. The fluid end assembly according to claim 5 wherein said first
obtuse angle measures about 125.degree. and said second obtuse
angle measures about 115.degree..
9. The fluid end assembly according to claim 5 further comprising a
pony rod assembly attached by means of threaded fasteners to said
plunger for connecting said plunger to a reciprocating part of the
power end of a pump.
10. The fluid end assembly according to claim 5 wherein said
suction valve includes: a first valve seat in said suction passage
a piston having a head for engaging the top of valve seat and a
stem extending downwardly from said head through said valve seat,
said stem having a transverse aperture; a valve guide being
positioned adjacent the bottom of said first valve seat and
slidably receiving said stem; a valve keeper being fitted upon said
stem such that said valve guide is disposed between said valve seat
and said valve keeper; a keeper pin being slidably positioned
within said transverse aperture in said stem and abutting said
keeper; and, a compressed spring being positioned between said
valve guide and said keeper so as to normally retain said head in
flush engagement with the top of said valve seat thereby closing
said suction valve.
11. The fluid end assembly according to claim 5 wherein said
discharge valve includes a valve seat positioned within discharge
passage; a piston releasably engaging said valve seat, said piston
having a head for releasably engaging said valve seat and stem
extending upwardly from said head and away from said valve seat; a
valve guide mounted in said discharge passage adjacent said valve
seat, said valve guide having a socket for receiving said stem and
also having a plurality of apertures that traverse said valve guide
and intersect said socket to provide pressure relief to said
socket; and, a compressed spring being disposed between said valve
guide and said head for normally retaining said head in flush
engagement with the top of said valve seat and keeping said
discharge valve closed.
12. A fluid end assembly, comprising: a pump housing with: a
plunger bore having a closed inner end and an open outer end; a
suction passage intersecting said plunger bore; a discharge passage
intersecting both said plunger bore and said suction passage such
that said discharge passage, said suction passage and said plunger
bore radiate outwardly from their point of intersection to define a
shape resembling a "Y", said discharge passage having a diameter
greater than that of said suction passage; an outlet passage
intersecting said discharge passage substantially at right angles;
a reciprocating plunger being located in said plunger bore; a
suction valve being located in said suction passage; a discharge
valve being located in said discharge passage; and, a fluid supply
manifold secured to said pump housing and being in fluid
communication with said suction passage.
13. The fluid end assembly according to claim 12 wherein said
suction passage and said discharge passage are each provided with
portions of reduced diameter that define a pair of decks for
supporting, respectively, said suction valve and said discharge
valve within said suction passage and said discharge passage.
14. The fluid end assembly according to claim 12 wherein said
discharge passage has a diameter that is greater than that of said
suction passage so that the suction valve can be removed from said
pump housing through said discharge passage.
15. The fluid end assembly according to claim 12 further comprising
a pony rod assembly bolted to said plunger.
16. The fluid end assembly according to claim 12 wherein said
suction valve includes: a first valve seat positioned within said
suction passage a piston having a head for engaging the top of said
first valve seat and a stem extending downwardly from said head
through said first valve seat, said stem having a transverse
aperture; a valve guide being positioned adjacent the bottom of
said first valve seat and slidably receiving said stem; a valve
keeper being fitted upon said stem such that said valve guide is
disposed between said first valve seat and said valve keeper; a
keeper pin being slidably positioned within said transverse
aperture in said stem and abutting said keeper; and, a compressed
spring being positioned between said valve guide and said keeper so
as to normally retain said head in flush engagement with the top of
said first valve seat thereby closing said suction valve.
17. The fluid end assembly according to claim 16 wherein said
discharge valve includes a second valve seat positioned within
discharge passage; a piston releasably engaging said second valve
seat, said piston having a head for releasably engaging said second
valve seat and a stem extending upwardly from said head and away
from said second valve seat; a valve guide mounted in said
discharge passage adjacent said second valve seat, said valve guide
having a socket for receiving said stem and also having a plurality
of apertures that traverse said valve guide and intersect said
socket to provide pressure relief to said socket; and, a compressed
spring being disposed between said valve guide and said head for
normally retaining said head in flush engagement with the top of
said second valve seat and keeping said discharge valve closed.
18. A piston and valve seat for said suction valve described in
claim 5 wherein: said valve seat is a tube with open, top and
bottom surfaces; said piston has a head for engaging said top
surface of said valve seat and a stem extending downwardly from
said head through said valve seat, said stem having a transverse
aperture; said valve has an engaged position wherein in said
engaged position an abutment is positioned within said transverse
aperture, and a compression spring is disposed between said head
and said aperture, and a compression spring is disposed between
said head and said aperture.
19. A discharge valve for the fluid end of claim 11, comprising: a
valve seat positioned within a discharge passage; a piston
releasably engaging said valve seat, said piston having a head for
releasably engaging said valve seat and stem extending upwardly
from said head and away from said valve seat; a valve guide mounted
in said discharge passage adjacent said valve seat, said valve
guide having a socket for receiving said stem and also having a
plurality of apertures that traverse said valve guide and intersect
said socket to provide pressure relief to said socket; and a
compressed spring being disposed between said valve guide and said
head for normally retaining said head in flush engagement with the
top of said valve seat and keeping said discharge valve closed.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to pumps having
pumping chamber pressure-responsive fluid distributors and, more
particularly, to such pumps having distributors positioned opposite
the pumping member's end face.
BACKGROUND OF THE INVENTION
[0002] It is often difficult to produce hydrocarbons in an economic
manner from low permeability reservoir rocks. Production rates are
often boosted by resorting to hydraulic fracturing, a technique
that increases rock permeability by opening channels through which
hydrocarbons can flow to recovery wells. During hydraulic
fracturing, a fluid is pumped into the earth under high pressure
(sometimes as high as 50,000 PSI) where it enters a reservoir rock
and cracks or fractures it. Proppants are carried in suspension by
the fluid into the fractures. When the pressure is released, the
fractures partially close on the proppants, leaving channels for
oil and gas to flow.
[0003] Specialized pumps are used to develop the pressures
necessary to complete a hydraulic fracturing procedure or "frac
job." These pumps are usually provided with fluid ends having both
reciprocating plungers that place fluids under pressure and valves
that control fluid flow to and from the plungers. The body of a
fluid end is typically a collection of parts releasably fastened
together to provide access to internal components for servicing.
Unfortunately, the joints between the parts and the supporting
features for the valves tend to weaken the body of a fluid end,
limiting its pressure rating, and making it susceptible to
corrosion, leaks and cracks as high, cyclic stresses take their
toll. Thus, it is not unusual for the bodies of fluid ends to
prematurely fail under load, cutting short their useful lives.
[0004] In an effort to reduce the number of failures of fluid ends,
"Y-type" fluid ends have been proposed. As is well known, Y-type
fluid ends reduce concentrated stresses in the body of a fluid end
by increasing the angles at which bores within the body intersect
one-another above 90.degree. to about 120.degree.. Unfortunately,
none of the proposed Y-type designs have seen widespread use or
great commercial success since such have been difficult and costly
to manufacture and equally difficult to service in the field. A
need, therefore, exists for an improved Y-type fluid end.
SUMMARY OF THE INVENTION
[0005] In light of the problems associated with the known fluid end
employed in high-pressure pumps that are prone to premature fatigue
failures, it is a principal object of the invention to provide a
fluid end assembly having a Y-type configuration that is very
robust, neither being prone to wear quickly nor fail under repeated
cyclic loading present during normal usage. Should parts of the
fluid end assembly wear or break during use, such are easy to
repair or replace. No special tools are required to accomplish the
task.
[0006] It is another object of the invention to provide a fluid end
assembly of the type described that is relatively compact in size
and is easy to transport. The fluid end assembly can be truck-,
trailer-, and skid-mounted to further facilitate its transport to
and from the "oil patch."
[0007] It is a further object of the invention to provide a Y-type
fluid end assembly of the type described whose internal, fluid flow
passageways have the shortest practicable lengths so as to minimize
pressure losses as fluid moves through the fluid end. The
passageways are configured, in terms of the shapes of their
sidewalls and their positions relative to one another, so as to
minimize pressure losses as fluid moves through the fluid end
assembly. Thus, the fluid end assembly of this invention is
believed to be more efficient than conventional, fluid end
designs.
[0008] Still another object of the invention is to provide a fluid
end assembly that features turbulence-reducing suction and
discharge valves. The valves reduce pressure losses as fluids move
through the fluid end assembly thereby increasing the efficiency of
the fluid end assembly. The valves are configured such that major
portions of both can be removed from the assembly from a single
accessway for repair and replacement, conserving the operator's
time and resources.
[0009] It is an object of the invention to provide improved
elements and arrangements thereof in a fluid end assembly for the
purposes described which is lightweight in construction,
inexpensive to manufacture, and fully dependable in use.
[0010] Briefly, the fluid end assembly in accordance with this
invention achieves the intended objects by featuring a pump housing
with a plunger bore having a closed inner end and an open outer
end. A suction passage intersects the plunger bore and a discharge
passage intersects both the plunger bore and the suction passage
such that the discharge passage, the suction passage and the
plunger bore radiate from their point of intersection to define a
shape resembling a "Y". An outlet passage intersects the discharge
passage substantially at right angles. A reciprocating plunger is
located in the plunger bore whereas a suction valve is located in
the suction passage and a discharge valve is located in the
discharge passage. A fluid supply manifold is secured to the pump
housing and is in fluid communication with the suction passage.
[0011] The foregoing and other objects, features and advantages of
the present invention will become readily apparent upon further
review of the following detailed description of the preferred
embodiment as illustrated in the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
[0012] The present invention may be more readily described with
reference to the accompanying drawing that is a cross-sectional
view of a fluid end assembly in accordance with the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] Referring now to the drawing, a fluid end assembly in
accordance with the present invention is shown at 10. Fluid end
assembly 10 includes a pump housing 12 having a plunger bore 14
within which a plunger 16 reciprocates. At its inner end, plunger
bore 14 terminates in a pumping chamber 18 that is supplied with
fluid by a suction passage 20 in pump housing 12. Fluid pressurized
by plunger 16 exits pumping chamber 18 through a discharge passage
22 in pump housing l2. Fluid flow through suction and discharge
passages 20 and 22 is controlled by means of suction and discharge
valves 24 and 26 located therein. Suction valve 24 connects a fluid
supply manifold 28 to suction passage 20 and discharge valve 26
ports fluid from discharge passage 22 into an outlet passage 30 for
release from fluid end assembly 10.
[0014] Pump housing 12 is a steel forging whose overall height and
width are substantially the same, making such compact and
relatively easy to transport. To lower weight and increase
strength, housing 12 is provided with a plunger section 32 of
reduced height that contains plunger bore 14 and is adapted for
attachment to the power end 34 of a high-pressure pump by a
plurality of stay rods 36. A suction section 38, containing suction
passage 20, is integrally formed with plunger section 32 and
extends forwardly and downwardly from plunger section 32.
Similarly, a discharge section 40, containing discharge passage 22,
is integrally formed with plunger and suction sections 32 and 38
and extends forwardly and upwardly from plunger section 32. Suction
and discharge sections 38 and 40 taper from their inner ends, where
such are at least 2.5 times the width of the passage 20 or 22 they
contain, to their outer ends where such are about 1.5 times the
width of contained passage 20 or 22.
[0015] Plunger bore 14 is provided within pump housing 12 along a
first centerline A. At its outer end, plunger bore 14 is widened
and partly threaded at 42 to receive a packing and gland nut unit
44 giving a fluid-tight seal around plunger 16. A lubricating port
46 in plunger section 32 permits lubricant to be provided to
plunger 16 within the packing and gland nut unit 44. As was noted
above, at its inner end, plunger bore 14 terminates in pumping
chamber 18.
[0016] Suction passage 20 intersects plunger bore 14 and has a
second centerline B that is coplanar with first centerline A and
intersects first centerline A at a first reference point AB to
define a first obtuse angle. Suction passage 20 extends from the
bottom to the top of suction section 38 of pump housing 12.
Preferably, suction passage 20 has a zone of reduced diameter
extending upwardly from the bottom of suction section 38 to a point
about halfway to pumping chamber 18. The top of the zone of reduced
diameter forms a deck 48 upon which a cylindrical, suction valve
seat 50 rests.
[0017] Discharge passage 22 intersects both plunger bore 14 and
suction passage 20 and has a third centerline C. Third centerline C
is coplanar with second centerline B and first centerline A that it
intersects at a second reference point AC so as to define a second
obtuse angle Additionally, discharge passage 22 has a zone of
reduced diameter extending between the bottom of discharge passage
22 and about the midpoint of discharge passage 22 the top of which
defines a deck 52 upon which a cylindrical, discharge valve seat 54
rests. The bottom of deck 52, like the bottom of deck 48, slopes
outwardly and upwardly at an angle of approximately 30.degree..
This slope allows decks 48 and 52 to transfer forces imparted by
valve seats 50 and 54 evenly to pump housing 12 thus reducing the
likelihood of fatigue-induced cracks forming in housing 12 at these
locations.
[0018] Discharge passage 22 and seat 54 are provided with diameters
that are greater than that of suction valve seat 50 and the piston
56 that engages valve seat 50. With plunger 16 positioned at the
beginning of its stroke into pumping chamber 18, suction valve seat
50 and piston 56 can be pulled from pump housing 12 through
discharge passage 22 for inspection, repair or replacement. Thus,
plunger 16 does not have to be removed from pump housing 12 to
service suction valve 24.
[0019] Reference points AB and AC are spaced along first centerline
A with reference point AB being located nearer to the threaded end
42 of plunger bore 14 to facilitate the movement of fluid from
pumping chamber 18 into discharge passage 22. Obtuse angle,
measuring about 125.degree., is greater than obtuse angle ,
measuring about 115.degree., to facilitate access to suction
passage 20 and valve 24. The resulting Y-shaped configuration
offered by the intersections of plunger bore 14, suction passage
20, discharge passage 22 and their associated centerlines A, B and
C reduces stresses within pump housing 12 during use and minimizes
the likelihood of pump housing 12 failing over time.
[0020] Outlet passage 30 extends through discharge section 40 from
one of its ends to the other. To either end of discharge section 40
can be connected one or more conduits (not shown) to carry
pressurized fluid away from fluid end assembly 10. This pressurized
fluid is, of course, used to perform work.
[0021] Manifold 28 includes a tubular body 58 from which a tubular
connector 60 extends upwardly to place tubular body 58 and suction
passage 20 in fluid communication with one another. Connector 60 is
axially aligned with centerline B and admits the bottom of suction
valve 24 into manifold 28 to reduce the height of fluid end
assembly 10. The top of connector 60 is provided with a radial
flange 62 that, by means of threaded fasteners 64, is attached to
the bottom of suction section 38 of pump housing 12. The opposite
ends of tubular body 58 are open and connected to a fluid source
when fluid end assembly 10 is operated.
[0022] Suction valve 24 has valve seat 50 and piston 56 movably
joined to valve seat 50. Piston 56 has a head 66 for engaging the
top of valve seat 50 and a stem 68 extending downwardly from head
66 through valve seat 50. A valve guide 70 is positioned adjacent
the bottom of valve seat 50 and slidably receives stem 68. A valve
keeper 72 is fitted upon stem 68 such that valve guide 70 is
disposed between valve seat 50 and keeper 72. A keeper pin 74 is
slidably positioned within a transverse aperture 76 in stem 68 and
abuts the bottom of keeper 72. A compressed spring 78 is positioned
between, and exerts opposing forces upon, valve guide 70 and keeper
72 so as to normally retain head 66 in flush engagement with the
top of valve seat 50 thus closing suction valve 24.
[0023] Discharge valve 26 includes valve seat 54 and a piston 80
for engaging valve seat 54. Piston 80 has a stem 82 that extends
upwardly from a head 84 away from valve seat 54 and into a socket
86 in a valve guide 88 retained in passage 22 by a threaded
discharge nut 90. A number of apertures 92 traverse guide 88 and
intersect socket 86 to provide pressure relief to socket 86. A
compressed spring 94 is disposed between valve guide 88 and head 84
for normally retaining head 84 in flush engagement with the top of
valve seat 54 and keeping discharge valve 26 closed. When plunger
16 pressurizes fluid in chamber 18, the fluid flows through seat
54, past head 84, and into outlet passage 30.
[0024] Plunger 16 is a hollow cylinder that is open at its outer
end and is closed at its inner end. As shown, the outer end of
plunger 16 is provided with a central recess 96 surrounded by a
plurality of threaded apertures 98. The inner end of plunger 16, on
the other hand, is tapered and rounded at 100 in a manner
resembling the tip of a bullet. It is believed that this
bullet-like configuration reduces turbulence and pressure losses
within pumping chamber 18, especially as plunger 16 travels
forward, thereby displacing fluid from pumping chamber 18 more
efficiently.
[0025] A pony rod extension 102 connects the reciprocating
crosshead (not shown) of power end 34 to plunger 16 and allows
plunger 16 to be removed from pump housing 12 without need to
remove housing 12 from power end 34. Rod extension 102 includes a
pony rod 104 for attachment to a reciprocating crosshead and a pony
rod adapter 106 that connects pony rod 104 to plunger 16.
Preferably, pony rod 104 is a hollow cylinder that has an integral
plug 108 at one of its ends and a radial flange 110 at the other of
its ends. Plug 108 has a central socket 112 surrounded by a
plurality of threaded apertures 114 and flange 110 has a plurality
of apertures 116 through which threaded fasteners (not shown) are
extended to fasten pony rod 104 to a crosshead. Adapter 106,
however, includes a cylindrical body 118 having an outer diameter
that is less than that of both plunger 16 and pony rod 104.
Apertured peripheral flanges 120 and 122 at the opposite ends of
cylindrical body 118 permit threaded fasteners 124 to pass into
apertures 98 and 114 and connect adapter 106 to both plunger 16 and
pony rod 104. Pins 126 and 128 extend from the opposite ends of
adapter 106 for snug positioning, respectively, in central socket
112 and recess 96 to ensure that the axial alignment of pony rod
104, adapter 106 and plunger 16 is maintained at all times while
assembly 10 is in operation.
[0026] Fluid end 10 produces useful work by pressurizing fluid by
means of the reciprocating action of plunger 16. Valves 24 and 26,
of course, permit fluid pressurized by plunger 16 to move only in
one direction from manifold 28 to outlet passage 30. The Y-shaped
configuration of bore 14 and passages 20 and 22 in addition to the
thick, tapered walls provided to plunger, suction and discharge
sections 32, 38 and 40 pump housing 12 with a construction that is
durable and not prone to fail under repeated cyclic loading
developed by plunger 16. Should plunger 16, valves 24 and 26,
packing and gland nut unit 44, or pony rod extension 102 ever
require servicing, such are easy to repair or replace with ordinary
tools and without major disassembly of fluid end assembly 10.
[0027] While the invention has been described with a high degree of
particularity, it will be appreciated by those skilled in the art
that modifications may be made thereto. Therefore, it is to be
understood that the present invention is not limited to the sole
embodiment described above, but encompasses any and all embodiments
within the scope of the following claims.
* * * * *