U.S. patent application number 14/211027 was filed with the patent office on 2014-09-18 for fluid end with protected flow passages and kit for same.
This patent application is currently assigned to Acme Industries, Inc.. The applicant listed for this patent is Acme Industries, Inc.. Invention is credited to Fred Young.
Application Number | 20140260954 14/211027 |
Document ID | / |
Family ID | 51521472 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140260954 |
Kind Code |
A1 |
Young; Fred |
September 18, 2014 |
FLUID END WITH PROTECTED FLOW PASSAGES AND KIT FOR SAME
Abstract
This application describes systems for protecting steel fluid
end body flow passages from direct impingement by high pressure
fracking fluid. These fluid end body flow passages are protected by
components in the form of cartridges and sleeves, This disclosure
also describes kits and methods which utilize these systems to
provide enhanced erosion and corrosion resistance as well as
improved fatigue properties and extended service life to these
fluid ends.
Inventors: |
Young; Fred; (Naperville,
IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Acme Industries, Inc. |
Elk Grove Village |
IL |
US |
|
|
Assignee: |
Acme Industries, Inc.
Elk Grove Village
IL
|
Family ID: |
51521472 |
Appl. No.: |
14/211027 |
Filed: |
March 14, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61800852 |
Mar 15, 2013 |
|
|
|
Current U.S.
Class: |
92/169.4 |
Current CPC
Class: |
E21B 43/26 20130101;
F04B 53/14 20130101; F04B 53/168 20130101; F04B 53/007 20130101;
F04B 19/22 20130101; F04B 53/16 20130101; F04B 53/166 20130101;
F04B 53/10 20130101 |
Class at
Publication: |
92/169.4 |
International
Class: |
F04B 39/12 20060101
F04B039/12; F04B 53/16 20060101 F04B053/16 |
Claims
1. In a fluid end of a reciprocating pump for delivery of fracking
fluid at high pressure into a well for recovery of oil and natural
gas trapped in shale rock formations, said fluid end having at
least one fluid cylinder assembly including: a body having a first
bore which includes a reciprocating plunger; a second bore which
includes a suction valve; and a third bore which includes a
discharge valve, said first bore being generally perpendicular to
both said second and third bores which are in flow communication
with each other, an outlet of said second bore and an inlet of said
third bore defining a chamber with said first bore that receives a
reciprocating plunger for drawing fracking fluid into said chamber
at low pressure and discharging said fracking fluid at high
pressure. the improvement comprising: at least one tubular sleeve
in said first bore, the outer surface of said tubular sleeve
configured to be in direct contact with the surface of said first
bore that surrounds said at least one tubular sleeve; at least one
tubular cartridge in a fluid passage defined by said second and
third bores, the outer surface of said at least one tubular
cartridge configured to be in direct contact with the surface of
said second and third bores that surrounds said at least one
tubular cartridge; a fluid-tight seal between contacting surfaces
of said at least one sleeve and said at least one cartridge; said
at least one sleeve and said at least one cartridge, when installed
in said fluid end cylinder assembly, cooperating to overlie the
fluid end body portions that surround each of them and to protect
them from direct impingement thereon by high pressure fracking
fluid passing through said fluid end cylinder assembly providing
said fluid end with enhanced erosion and corrosion resistance as
well as improved fatigue properties and extended service life.
2. The improvement of claim 1 wherein said second and third bores
respectively contain first and second tubular cartridges.
3. The improvement of claim 1 wherein a gasket is provided between
said at least one tubular sleeve and said at least one tubular
cartridge.
4. The improvement of claim 1 in which an outer cylindrical surface
on one of said at least one tubular sleeve and said at least one
tubular cartridge is in sealing contact with an annular,
interior-facing edge surface of the other of said at least one
tubular sleeve and at least one tubular cartridge.
5. The improvement of claim 1 wherein said at least one cartridge
and said at least one sleeve is composed of a material with
enhanced erosion and corrosion resistance was well as improved
fatigue resistant properties.
6. The improvement of claim 5 wherein said material is a metal
selected from the group consisting of stainless steel,
Inconel.RTM., Incoloy.RTM. and other metals and alloys exhibiting
suitable corrosion resistance, erosion resistance and strength.
7. The improvement of claim 1 wherein said at least one tubular
sleeve and said at least one tubular cartridge has a protective
coating or surface treatment applied to enhance the erosion and
corrosion resistance and fatigue properties thereof.
8. A fluid end of a reciprocating pump for delivery of fracking
fluid at high pressure into a well to extract and recover oil and
natural gas trapped in shale rock formations, said fluid end having
at least one fluid cylinder assembly comprising: a chamber formed
therein; a first bore in communication with said chamber, said
first bore including a reciprocating plunger for effecting
pressurization in said chamber to draw fracking fluid therein at
low pressure and to discharge said fracking fluid at high pressure;
a second bore formed in said fluid and in communication with said
chamber, said second bore including a section valve for receiving
fracking fluid at low pressure into said chamber; a third bore
formed in said fluid end in communication with said chamber, said
third bore including a discharge valve for release of high pressure
fracking fluid through an outlet in said fluid end; said second and
third bores defining a fluid passageway in said fluid end cylinder
assembly; at least one tubular sleeve in direct contact with said
first bore, the outer surface of said tubular sleeve configured to
be in an interference fit with the surface of said first bore that
surrounds said at least one tubular sleeve; at least one tubular
cartridge in said fluid passageway, the outer surface of said at
least one tubular sleeve configured to be an interference fit with
the surface of said passageway surrounding said at least one
tubular cartridge; a fluid tight seal between contacting surfaces
of said at least one sleeve and said at least one cartridge; said
at least one sleeve and said at least one cartridge cooperating to
overlie the fluid end body portions surrounding each of them and to
protect said underlying fluid body portions from direct impingement
thereon by high pressure fracking fluid passing through said fluid
end and providing said fluid end with enhanced erosion and
corrosion resistance as well as improved fatigue properties and
extended service life.
9. The fluid end of claim 8 wherein said second and third bores
respectively contain first and second tubular cartridges.
10. The fluid end of claim 8 in which an outer cylindrical surface
on one of said at least one tubular sleeve and said at least one
tubular cartridge is in fluid tight sealing contact with an annular
interior-facing edge surface of the other of said at least one
tubular sleeve and said at least one tubular cartridge.
11. The fluid end of claim 8 edge surface wherein said at least one
cartridge and said at least one sleeve is composed of a material
with enhanced erosion and corrosion resistance as well as improved
fatigue resistant properties.
12. The fluid end of claim 11 wherein said material is a metal
selected from the group consisting of stainless steel,
Inconel.RTM., Incoloy.RTM. and other metals and alloys exhibiting
suitable corrosion resistance, erosion resistance and strength.
13. The fluid end of claim 12 wherein said at least one tubular
sleeve and said at least one tubular cartridge has a protective
coating or surface treatment applied to enhance the erosion and
corrosion resistance and fatigue properties thereof.
14. A kit for enhancing the service life of a fluid end of a
reciprocating pump used in the recovery of oil and natural gas
trapped in shale rock formations, said fluid end with at least one
fluid cylinder including: a body having a first bore which includes
a reciprocating plunger; a second bore which includes a suction
valve; and a third bore which includes a discharge valve, said
first bore being generally perpendicular to both said second and
third bores which are in flow communication with each other, an
outlet of said second bore and an inlet of said third bore defining
a chamber in alignment with said first bore that receives said
reciprocating plunger for drawing fracking fluid into said chamber
at low pressure and discharging said fracking fluid at high
pressure, said kit comprising: at least one tubular sleeve adapted
to be received in said first bore, the outer surface of said first
tubular sleeve configured to be in direct contact with the surface
of said first bore that surrounds said at least one tubular sleeve;
at least one tubular cartridge adapted to be received in said
second bore, the outer surface of said at least one cartridge being
configured to be in direct contact with the inner surface of said
second bore; said at least one sleeve and said at least one
cartridge when installed in said fluid body cooperating to protect
the fluid end body portions surrounding the outer surfaces of said
at least one sleeve and said at least one cartridge from
impingement by high pressure fracking fluid passing through said
fluid end to provide said fluid end with enhanced erosion and
corrosion resistance as well as improved fatigue properties and
with extended service life.
15. The kit of claim 14 wherein each of said at least one tubular
sleeve and said at least one tubular cartridge is composed of a
material with enhanced erosion and corrosion resistance and fatigue
properties.
16. The kit of claim 14 wherein each of said at least one tubular
sleeve and said at least one tubular cartridge has a protective
coating or surface treatment applied to enhance it prior to being
installed in said fluid body applied to enhance the erosion and
corrosion resistance and fatigue properties.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from U.S. Provisional
Patent Application Ser. No. 61/800,852, filed Mar. 15, 2013, the
disclosure of which is hereby incorporated by reference in its
entirety.
FIELD OF THE INVENTION
[0002] The present invention generally relates to hydraulic
fracturing pump systems and, more particularly, to the fluid ends
of multiplex reciprocating fracturing pumps.
[0003] 1. Background
[0004] Multiplex reciprocating pumps are generally used to pump
high pressure fracturing fluids into wells for recovery of oil and
gas trapped in shale formations and the like. Typically, these
pumps have two sections, a power end which is coupled to a diesel
engine and transmission that drives the pump and plungers in the
fluid ends in which a mix of water, sand and chemicals are
pressurized up to 15,000 psi or more.
[0005] These multiplex reciprocating pumps are commonly in the form
of triplex pumps having three fluid cylinders and quintuplex pumps
that have five cylinders. It will be appreciated, however, that the
present disclosure has application to pumps which can utilize the
features thereof in forms other than the triplex and quintuplex
pumps. The fluid ends of these pumps typically comprise a single
block having cylinders bored therein and are commonly referred to
as monoblock fluid ends or an assembly of individual bodies with
cylinders, referred to as modular fluid ends.
[0006] The pumping cycle of a fluid end is composed of two stages,
a suction cycle during which a piston moves outward in a bore,
thereby lowering the fluid pressure in the inlet to a fluid end and
a discharge cycle during which the plunger moves forward in the
plunger bore, thereby progressively increasing the fluid pressure
to a predetermined level for discharge through a discharge pipe to
a well site.
[0007] Fluid ends used in well site applications for oil and gas
exploration have limited service life due to fatigue crack
failures. These failures are a result of operating pressures,
mechanical stresses, erosion and corrosion of the internal passages
which have been addressed in prior art efforts with limited
success.
[0008] 2. Discussion of the Prior Art
[0009] International Application No. PCT/IB2011/002771
(International Publication No. WO 2012 052842 A2 entitled "Fluid
End Reinforced With Abrasive Resistant Insert, Coating or Lining")
describes the use of inserts in wear prone areas only and, as such,
does not provide erosion, corrosion and fatigue crack protection
throughout the entire flow passages in the fluid end.
[0010] U.S. Patent Publication 2008/0080994 A1, "Fluid End
Reinforced With a Composite Material," is directed to a fluid end
of a reciprocating pump wherein carbon steel thin base material is
formed into three tubes which are welded and then hydroformed to
give a cross-like configuration. That structure is reinforced with
a composite that provides some additional stress resistance and
reduced weight, however, it does not utilize the inherent benefits
of the originally designed high strength steel in the fluid
block.
[0011] U.S. Pat. No. 3,786,729 is directed to a liner seal for the
plunger bore and does not address the protection of high stress
areas such as those associated with intersecting bores.
SUMMARY OF THE INVENTION
[0012] This disclosure is generally directed to a system for
substantially protecting the portions of the fluid end body flow
passages from impingement by high pressure fracking fluid passing
therethrough to provide enhanced erosion and corrosion resistance
as well as improved fatigue properties and extended service
life.
[0013] A first aspect of this disclosure is directed to sleeve and
cartridge components which cooperate to protect fluid end body
portions surrounding the outer surface thereof from direct
impingement thereon by high pressure fracking fluid passing through
said fluid end.
[0014] A second aspect of this disclosure is directed to a sleeve
that is received in a plunger bore of a fluid end body which sleeve
includes a pair of apertures that are connected to, and in flow
communication with, the outlet of the suction bore and the inlet of
in the discharge bore.
[0015] In accordance with another aspect of the disclosure, a kit
which includes one or two sleeves, a cartridge, and a plug is
provided for installation in a conventional fluid end steel body
which, when installed therein, cooperate to protect the fluid end
body portions surrounding the outer surfaces thereof from
impingement by high pressure fracking fluid passing through said
fluid end.
[0016] A further aspect of the present invention is directed to a
method of installing one or more components in the flow passages of
a fluid end body of a reciprocating pump used in the recovery of
oil and gas for the purpose of extending the service life thereof
and to minimize the effects of erosion, corrosion and fatigue, such
components being configured and located within one or more bores in
said fluid end body to protect the portions of said fluid body
surrounding those components including portions associated with
high stress areas such as the corners of intersecting bores.
[0017] It is to be understood that the foregoing general
description and the following detailed description are exemplary
and provided for purposes of explanation only and are not
restrictive of the subject matter claimed. Further features and
objects of the present disclosure will become apparent in the
following description of the example embodiments and from the
appended claims.
DESCRIPTION OF THE DRAWINGS
[0018] In describing the preferred embodiments, reference is made
to the accompanying drawing figures or in like parts have like
reference numerals and wherein:
[0019] FIG. 1 is a schematic illustration of a power end and fluid
end of a reciprocating pump used in the recovery of oil and natural
gas;
[0020] FIG. 2 is a perspective view of the block component of the
fluid end shown in FIG. 1;
[0021] FIG. 3 is a side elevational view as seen from the mounting
flange surface of the fluid end block shown in FIGS. 2 and 3;
[0022] FIG. 4 is a top plan view of the fluid end block shown in
FIG. 2;
[0023] FIG. 5 is a sectional view of the fluid end block shown in
FIG. 3 taken along the sectional line 5-5 of FIG. 3 which has been
modified to accept the components of the first embodiment described
herein, but prior to the installation of such components;
[0024] FIG. 6 is a perspective view of a sleeve component suitable
for use in accordance with the first embodiment of the present
disclosure;
[0025] FIG. 7 is an end view of the sleeve shown in FIG. 6;
[0026] FIG. 8 is a side elevational view of the sleeve shown in
FIGS. 6 and 7;
[0027] FIG. 9 is a sectional view of the sleeve shown in FIGS. 6-8
taken along the section line 9-9 of FIG. 7;
[0028] FIG. 10 is a perspective view of a cartridge component
suitable for use in the first embodiment of this disclosure;
[0029] FIG. 11 is a front elevational view of the cartridge shown
in FIG. 10;
[0030] FIG. 12 is an end view of the cartridge component shown in
FIGS. 10-11;
[0031] FIG. 13 is a side elevational view of the cartridge shown in
FIGS. 10-12;
[0032] FIG. 14 is a sectional view of the cartridge shown in FIGS.
10-13 taken along the line 14-14 of FIG. 11;
[0033] FIG. 15 is a perspective view of an end plug suitable for
use in the first embodiment of this disclosure;
[0034] FIG. 16 is a top plan view of the plug shown in FIG. 15;
[0035] FIG. 17 is a side elevational view of the plug shown in
FIGS. 15 and 16;
[0036] FIG. 18 is a bottom plan view of the plug shown in FIGS.
15-17;
[0037] FIG. 19 is a sectional view of the plug shown in FIGS. 15-18
taken along the section line 19-19 of FIG. 16;
[0038] FIG. 20 is a schematic sectional view illustrating a
procedure of installing the sleeve component shown in FIGS. 7-10 in
a fluid end in accordance with the first embodiment of the present
disclosure;
[0039] FIG. 21 is a schematic view illustrating a procedure for
installing the cartridge of FIGS. 10-14 in a fluid end block in
accordance with the first embodiment of the present disclosure;
[0040] FIG. 22 is a schematic view, partially in section,
illustrating the assembly of the components of the first embodiment
of the present disclosure;
[0041] FIG. 23 is an assembly drawing, partially in section,
illustrating another embodiment of the present disclosure which
utilizes a single sleeve component;
[0042] FIG. 24 is a perspective view of a sleeve which can be used
in accordance with the embodiment of FIG. 23; and
[0043] FIG. 25 is a perspective view of a retainer nut suitable for
use with the embodiment shown in FIG. 23.
DETAILED DESCRIPTION OF THE INVENTION
[0044] In accordance with an important aspect of the present
disclosure, the subject invention is particularly suited for use in
existing fluid end designs, however, it is not restricted to those
designs and can be utilized in other high pressure pumping
applications where operating pressures, mechanical stresses,
erosion and corrosion of internal passages are a concern. For the
purpose of illustration, however, it will be described in
conjunction with a conventional triplex fluid end such as is
generally shown in FIGS. 1-5.
[0045] Referring to FIG. 1, a triplex reciprocating pump system is
generally designated by the reference numeral 10 and includes a
power end 11, typically driven by a diesel engine and transmission,
which is coupled to a pump body or fluid end 12 that is supplied
with water and other ingredients for the fracking fluid via an
inlet 13. It is pressurized in the fluid end and discharged through
a high pressure outlet 14 therein. Fluid end 12 includes a mounting
surface 16 which can be used to directly secure the fluid end to
the power end by plurality of bolts 17.
[0046] As best shown in FIGS. 2-5, the fluid end 12 includes, a
block 12a formed from a high strength steel forging, which is
machined to provide a first or plunger bore 18, a second or suction
bore 19, center chamber 20 for pressurization of the fracking fluid
and a third bore or high pressure discharge bore 21. Each of the
high pressure discharge bores 21 shown in FIG. 5 feeds into a
common internal high pressure discharge passage 22 which directly
communicates with the high pressure discharge outlet 14.
[0047] The components of this first disclosed embodiment include a
sleeve component, the details of which are shown in FIGS. 6-9, a
cartridge component, the details of which are shown in FIGS. 10-14,
a combination retainer/positioning plug, the details of which are
shown in FIGS. 15-19 and the assembly of these components with
conventional internal valves, seals, etc. are shown in FIG. 22.
[0048] In FIGS. 6-9, the cylindrical sleeve component of the first
disclosed embodiment is designated by the reference numeral 25 and
can be composed of stainless steel, Inconel.RTM. and Incoloy.RTM.
and other metal and alloys exhibiting suitable corrosion and
erosion resistance and strength. If desired, coatings and surface
treatments may be applied to the surfaces of the sleeves to improve
the corrosion and erosion characteristics thereof. As shown, sleeve
component 25 includes a first sleeve portion 25a, a second sleeve
portion 25b which are coupled to each other by integral
interconnecting bridge portion 25c and 25d. The outer surfaces of
the first and second sleeve portions 25a and 25b are configured to
be respectively received in direct contact with a first portion of
the first bore, the plunger bore and a second portion of the first
bore that can also be referred to as an access bore.
[0049] Sleeve 25 also includes a pair of flow passage apertures 26
and 27 defined by inner edges of bridge portions 25c and 25d which
are configured to be in alignment with the second or suction bore
19 and third or high pressure discharge bore 21 when the sleeve is
installed in a fluid cylinder of the fluid end 12.
[0050] If desired, first tubular sleeve portion 25a and second
tubular sleeve portion 25b may be in the form of two separate
sleeves (without the interconnecting bridge portions) which are
respectively received in the first and second portions of the first
bore, namely the plunger and access bores.
[0051] In FIGS. 10-14, the cylindrical cartridge component of the
first disclosed embodiment is designated by the reference numeral
30. As shown, cartridge component includes a first portion 30a
which is configured to be received in the second or suction bore
19, a pair of apertures 30b and 30c, an upper portion 30d are
configured to be received in the third or high pressure discharge
bore 30d and a bottom edge 30e that engages a removable plug which
will be more fully described below. As with sleeve 25, the
cartridge 30 can be composed of stainless steel, Inconel.RTM.,
Incoloy.RTM. as well as other metals and alloys. Correspondingly,
coatings and surface treatments may be applied to the surfaces of
the cartridge to improve the corrosion and erosion characteristics
thereof. Apertures 30b and 30c are positioned to be in alignment
with the first and second portions of the first bore and the center
chamber 20 for accommodating the reciprocal movement of a plunger
31 (FIG. 23).
[0052] As will be described more fully later in conjunction with
FIG. 22, the perimeter of each aperture 30a and 30b includes a full
perimeter groove in which a gasket is received. These gaskets can
be formed from a suitable material which can withstand the high
pressures, chemicals and other conditions associated with tracking
operations and can include elastomers and synthetic fluorocarbon
polymers which exhibit these properties.
[0053] In accordance with an important aspect of this disclosure,
the sleeves and cartridges can be machined and/or surface treated
prior to their assembly into the block. This feature provides
greater flexibility in shaping the internal cylinder contours,
resulting in improved performance and durability of the fluid
end.
[0054] In some applications, it may be preferred to machine the
mating fluid end bore surfaces and the outside surfaces of the
sleeves and cartridge inserts to standard dimensions while
machining the internal surfaces to address the required
configurations. If desired, stress in the fluid end block may be
reduced by increasing the thickness of the sleeve and cartridge
cylinder to optimize the contours of the interfacing surfaces of
the fluid end block. For example, by having a larger radius between
intersecting bores of the block.
[0055] The plug component of this disclosed embodiment is
separately shown in FIGS. 15-19 and designated by the reference
numeral 32 which includes top end face having an annular rim 32a
configured for direct contact with cartridge bottom edge 30(e) and
a threaded annular sidewall 32b that is matingly received in the
threaded lower end of the second or suction bore 19 of fluid end
20. Plug 32 is sized to secure cartridge 30 in a fixed operating
position in the second and third bores with the apertures 30b and
30c in alignment with the first or plunger bore 18. As shown,
wrench-receiving recesses 33-36 can be provided in the bottom end
face 32c of plug 32 to facilitate its installation and removal in
and to the fluid end 12.
[0056] Installation of the sleeve 25 into the first or plunger bore
can be made from either end. For example, in the sleeve
installation step shown in FIG. 20 of the illustrated embodiment,
since the diameters of first bore 18 and sleeve 25 are larger than
the diameter of the open end of the bore opposite the mounting
flange, access to the bore can be made through the mounting flange
surface 16 (FIGS. 2-4). It will be appreciated, however, that if
the relative dimensions of bore 18 and sleeve 25 are appropriate,
access to the interior of the bore and insertion of the sleeve
could be done by removal of the retainer nut 53 (FIG. 22) covering
at that open end.
[0057] The surface of the bore 18 and sleeve 25 are machined to
provide a smooth surrounding surface and to an equally smooth outer
surface of the sleeve. In order to insure intimate
surface-to-surface direct contact between the bore and sleeve, the
sleeve can, if desired, have a slightly larger outer diameter than
the bore. A differential temperature between the two is created to
provide the necessary clearance during insertion and an
interference fit when the temperature of both are normalized.
[0058] As schematically depicted in FIG. 21, after the sleeve 25 is
installed, the cartridge is also machined to have outer diameter
which is again slightly larger than the machined diameters of the
second and third bores. A differential temperature between the
cartridge and these bores is then created to provide the assembly
clearance during this insertion and, when allowed to normalize, to
provide a tight, interference fit between the cartridge and the
second and third bores.
[0059] FIG. 22 illustrates a fluid cylinder assembly 40 in which
the sleeve, cartridge and plug components have been incorporated
along with the internal working elements (e.g., plunger, suction
valve, high pressure discharge valve, etc.). As shown, plunger 31
is received in the first bore 18 and reciprocates to effect
pressurization in the chamber 20 to draw fracking fluid therein, at
low pressure from the second or suction bore 19 containing a
suction valve 41 and associated intake mechanism 42.
Correspondingly, the third high pressure discharge bore 21 receives
pressurized fracking fluid from chamber 20 and discharges the same
into the internal high pressure passage 22 via discharge valve 43
and associated discharge mechanism 44.
[0060] Plunger packing assembly 49 and associated O ring seals in
seal carriers 46 and 47 function to prevent or at least minimize
passage of fracking fluid to the fluid body portions which surround
the sleeve 25 and cartridge 30 components. As shown in FIG. 22,
corrosion resistant material strips and beads 48 composed of a
titanium-reinforced epoxy putty such as Devcon.RTM. (ITW Devon,
Danvers, Mass.) can be utilized to minimizeor eliminate seepage of
fracking fluid into the portions of the fluid end body portions
surrounding the sleeve 25 and cartridge 30.
[0061] As schematically depicted in FIG. 22, during operation, the
regions designated by reference numeral 51 represent the highest
stress location in the assembled sleeve and cartridge.
Correspondingly, the region designated by the reference numeral 52
represents the highest stress location in the block which is lower
than the stress at region 51. Since the sleeve and cartridge
components by reason of their composition (e.g., high strength
stainless steel, Inconel.RTM., Incoloy.RTM., etc.) provide greater
resistance to erosion and corrosion as well as mechanical stresses
and fatigue than is provided by the forged steel block, it follows
the greater service life results.
[0062] Correspondingly, because the stress at the 52 location is
less than that at the 51 location it follows that the overall
stress on the block is reduced.
[0063] As previously noted, each of apertures 30b and 30c in the
cartridge 30 has a perimeter groove in which a gasket is received.
Those gaskets provide an effective seal between the outer surface
of the cartridge and the edges of apertures 26 and 27 of the sleeve
25 which withstand the high pressure of the fracking fluid in the
flow passages.
[0064] As shown, an access opening 18a at one end of bore 18
receives a removable retaining nut 53 to provide selective access
to the interior of the first bore, when desired.
[0065] FIGS. 23-25 depict a further embodiment of the present
invention where like parts have like reference numerals. This
embodiment is designated by the reference numeral 60 and includes a
modified block 61 formed from a high strength steel forging, a
modified first plunger bore 62 and a modified sleeve 63., composed
of high strength stainless steel, Inonel.RTM., Incolon.RTM. and
equivalent metals and alloys. It does not require a cartridge like
the cartridge 30 of the first embodiment.
[0066] As shown in FIG. 23, the modified bore includes a first
section 62a with an enlarged diameter and a second co-axially
aligned reduced diameter section 62b. The sleeve 63 includes a
first portion 63a which is sized to be tightly received in the bore
section 62a and a second portion 63b sized to be received in bore
section 62b with an interference fit between surfaces of bore
sections 62a and 62b and the corresponding cylindrical surface of
sleeve portions 63a and 63b.
[0067] A seal carrier plate 64 has a lip 64a which contacts an
outer end face of sleeve portion 63a. As shown, an annular shoulder
62c in the bore 62 between bore section 62a and 62b is in direct
contact with an annular back face 63e. Lip 64a of seal carrier 64
and the shoulder 62c serve to maintain the sleeve 63 in a fixed
position during tracking operations.
[0068] In accordance with an important feature of this disclosure,
sleeve 63 has a pair of apertures 63c and 63d, each of which is
defined by a full perimeter groove in which a gasket is received.
As with cartridge 30 of the first embodiment, the gaskets are
formed from a suitable material which can withstand the high
pressures and chemical erosion associated with tracking operations
and can include elastomers and synthetic fluorocarbon polymers that
exhibit these properties which are known to those skilled in the
art.
[0069] As shown in FIGS. 23 and 24, the sleeve apertures 63d and
63c can be located in the outer surface of bore 62a at locations
designated by reference numeral 65 and 66 and provide an effective
seal between the sleeve and fluid end body portions in contact
therewith.
[0070] The reference numerals 67 and 68 identify high stress
locations in the sleeve interior portions in the area adjacent the
sleeve apertures 63d and 63c and pressurization chamber 20. As
such, these areas are in locations wherein the resistance to
erosion, corrosion, high stress and fatigue provided by
high-strength stainless steel, Inconel.RTM., Incoloy.RTM. and
equivalents as contemplated by this disclosure is important.
[0071] As shown, an access opening 70 is enclosed by a removable
retaining nut 69.
[0072] While the subject invention has been disclosed and described
with illustrative examples, it will be appreciated that
modifications and/or changes may be made to those examples by those
skilled in the art without departing from the spirit and scope of
this invention as defined by the appended claims.
* * * * *