U.S. patent application number 11/000851 was filed with the patent office on 2006-06-08 for method and apparatus for mounting pumps within a suction vessel.
Invention is credited to William G. Haesloop.
Application Number | 20060120904 11/000851 |
Document ID | / |
Family ID | 36574435 |
Filed Date | 2006-06-08 |
United States Patent
Application |
20060120904 |
Kind Code |
A1 |
Haesloop; William G. |
June 8, 2006 |
Method and apparatus for mounting pumps within a suction vessel
Abstract
A pressure vessel and submerged electric motor pump system may
include a pressure vessel and at least two motor-pump assemblies
located within the pressure vessel. Each of the at least two
motor-pump assemblies may include a submersible electric motor and
a submersible pump in operable communication with the submersible
electrical motor. The submersible pump may be configured to pump
fluid from within the pressure vessel to without the pressure
vessel. A method for pumping a fluid from a pressure vessel may
include supplying a fluid to a pressure vessel, pumping the fluid
with two or more submersible electric motor pumps located within
the pressure vessel and discharging a pumped fluid from the
pressure vessel.
Inventors: |
Haesloop; William G.; (Las
Vegas, NV) |
Correspondence
Address: |
CANTOR COLBURN, LLP
55 GRIFFIN ROAD SOUTH
BLOOMFIELD
CT
06002
US
|
Family ID: |
36574435 |
Appl. No.: |
11/000851 |
Filed: |
December 1, 2004 |
Current U.S.
Class: |
417/423.3 ;
417/423.1 |
Current CPC
Class: |
F04D 1/063 20130101;
F04D 29/606 20130101; F04D 29/426 20130101; F04D 13/08
20130101 |
Class at
Publication: |
417/423.3 ;
417/423.1 |
International
Class: |
F04B 17/00 20060101
F04B017/00; F04B 35/04 20060101 F04B035/04 |
Claims
1. A pressure vessel and submerged electric motor pump system
comprising: a pressure vessel; at least two motor-pump assemblies
located within the pressure vessel, each of the at least two
motor-pump assemblies comprising: a submersible electric motor; and
a submersible pump in operable communication with the submersible
electrical motor, and the submersible pump is configured to pump
fluid from within the pressure vessel to without the pressure
vessel.
2. The pressure vessel and submerged electric motor pump system of
claim 1, wherein the pressure vessel comprises a pressure vessel
pump housing for each of the motor-pump assemblies.
3. The pressure vessel and submerged electric motor pump system of
claim 1, wherein each submersible pump is in operable communication
with a discharge line, and the discharge line is operably
communicable with discharge piping located externally of the
pressure vessel.
4. The pressure vessel and submerged electric motor pump system of
claim 1, wherein each submersible pump is in operable communication
with a vent line, and the vent line is operably communicable with
vent piping located externally of the pressure vessel.
5. The pressure vessel and submerged electric motor pump system of
claim 1, wherein each submersible electrical motor is in operable
communication with an electrical connection, and the electrical
connection is operably communicable with power source.
6. The pressure vessel and submerged electric motor pump system of
claim 1, wherein the pressure vessel has a pressure vessel vent
line, and the pressure vessel vent line is operably communicable
with piping located externally of the pressure vessel.
7. The pressure vessel and submerged electric motor pump system of
claim 1, wherein the pressure vessel has a drain line, and the
drain line is operably communicable with piping located externally
of the pressure vessel.
8. The pressure vessel and submerged electric motor pump system of
claim 1 configured such that: at least one pump is in operable
communication with a discharge line via a first valve; at least one
pump is in operable communication with a suction line via a second
valve; at least one pump is in operable communication with a vent
line via a third valve; and the at least one motor-pump assembly
may be removed from the pressure vessel by closing the first,
second and third valves.
9. The pressure vessel and submerged electric motor pump system of
claim 8, wherein the suction end of the at least one pump is in
operable communication with a foot valve, and the foot valve is in
operable communication with the pressure vessel.
10. The pressure vessel and submerged electric motor pump system of
claim 8, wherein the first valve, second valve and third valve are
foot valves.
11. The pressure vessel and submerged electric motor pump system of
claim 8, further configured such that the system may operate with
at least one motor-pump assembly removed from the pressure
vessel.
12. The pressure vessel and submerged electric motor pump system of
claim 1, wherein a number of motor-pump assemblies located within
the pressure vessel is selected between the range of three to
six.
13. The pressure vessel and submerged electric motor pump system of
claim 1 wherein at least one of the at least two motor-pump
assemblies is removably positionable within the pressure
vessel.
14. The pressure vessel and submerged electric motor pump system of
claim 13 wherein the at least one of the at least two motor-pump
assemblies includes a valve which is open when the at least one of
the at least two motor-pump assemblies is installed in the pressure
vessel and which closes when the at least one of the at least two
motor-pump assemblies is removed from the pressure vessel.
15. The pressure vessel and submerged electric motor pump system of
claim 1 wherein the pressure vessel includes a main tank for
receiving a portion of each of the at least two motor-pump
assemblies and for storing a fluid, and wherein the pressure vessel
further includes a support column, extending exteriorly of the main
tank, for each of the at least two motor-pump assemblies.
16. A submerged electric motor pump system comprising: a pressure
vessel; a single suction and phase separation vessel in operable
communication with the pressure vessel; at least two motor-pump
assemblies located within the pressure vessel, each of the at least
two motor-pump assemblies comprising: a submersible electric motor;
and a submersible pump coupled to the submersible electrical motor,
and the submersible pump is configured to pump fluid from within
the pressure vessel to without the pressure vessel.
17. The submerged electric motor pump system of claim 16 wherein
the pressure vessel is configured to be in operable communication
with the single suction and phase separation vessel via a single
set of suction, drain and vent lines.
18. A method for pumping a fluid from a pressure vessel, the method
comprising: supplying a fluid to a pressure vessel; pumping the
fluid with two or more submersible electric motor pumps located
within the pressure vessel; and discharging a pumped fluid from the
pressure vessel.
19. The method of claim 18 further comprising removing one of the
two or more submersible electric motor pumps from the pressure
vessel.
20. The method of claim 19 wherein supplying a fluid to a pressure
vessel, pumping the fluid with two or more submersible electric
motor pumps located within the pressure vessel, and discharging a
pumped fluid from the pressure vessel continues during removing one
of the two or more submersible electric motor pumps from the
pressure vessel.
21. A method for pumping a fluid from a pressure vessel, the method
comprising: supplying power to two or more submersible electric
motors located within the pressure vessel; rotating a rotor located
within each of the two or more submersible electric motors;
rotating two or more pump shafts each of which are within a
separate pump and each of which are in operable communication with
each of the rotors; pumping a fluid within the pressure vessel with
each of the pumps; and discharging a pumped fluid from the pressure
vessel.
Description
BACKGROUND
[0001] This invention relates generally to submerged electric motor
pumps, and, more particularly, this invention relates to submerged
electric motor pumps having a unique pressure vessel design.
[0002] Submerged electric motor pumps mounted in their own suction
or pressure vessels have found use in a variety of industries. Some
uses include, but are not limited to, the pumping of cryogenic
fluids such as liquid natural gas, and also corrosive and/or
hazardous liquids. A typical configuration of a pressure vessel
mounted submerged electric motor pump is one that has a centrifugal
pump and motor assembly installed in a pressure vessel, with the
pressure vessel filled with the liquid being pumped. The vessel may
be any material but typically is stainless steel, and designed and
fabricated in accordance with the appropriate pressure vessel code,
Section VIII of the ASME Pressure Vessel Code in the USA, for
instance.
[0003] FIG. 1 shows a known pressure vessel and submerged electric
motor pump system 10. A pressure vessel 14 has contained within it
a centrifugal pump 18 (either single or any number of stages) and
an electric motor 22. Each vessel is equipped with nozzles 26 or
fittings for suction, discharge 30, vent 34, drain 38 and
electrical connection 42. There additionally may be one or more
instrumentation connections 46.
[0004] It is common to install two or more pressure vessel mounted
submerged electric motor pump systems in order to increase the
total pumping capacity and/or to have spare capacity in case one of
the pressure vessel and submerged electric motor pump systems
should malfunction. Such systems are usually installed in parallel
with each other. The parallel systems are fed from a common suction
source with individual piping (and isolation valves) to the suction
nozzle of each of the pumps. Similarly each system is fitted with
individual discharge 30, vent line 34, drain line 38 and electrical
connections 42 and may also each have an instrumentation connection
46. Of course all of the fluid lines will have the appropriate
isolation and non-return valves. Further, the individual suction,
drain and vent lines may be routed to a separate suction and phase
separation vessel usually mounted at a higher elevation. In
addition, each of the individual pump suction vessels requires its
own mounting structure. The footprint of such a parallel
configuration is very large and requires much space. This space may
be difficult to come by in certain applications, such as
applications on board ships and/or off shore platforms, or floating
storage and regasification vessels (FSRV). Additionally, the
separate piping, lines, and valves coupled to each of the pressure
vessel and submerged electric motor pump systems increase cost and
make the overall system very complex, and therefore more difficult
and expensive to install and maintain.
BRIEF SUMMARY
[0005] Disclosed herein are embodiments relating to a pressure
vessel and submerged electric motor pump system including a
pressure vessel, at least two motor-pump assemblies located within
the pressure vessel, each of the at least two motor-pump assemblies
including a submersible electric motor, and a submersible pump in
operable communication with the submersible electrical motor, and
the submersible pump is configured to pump fluid from within the
pressure vessel to without the pressure vessel.
[0006] Also disclosed herein are embodiments relating to a system
including a pressure vessel, a single suction and phase separation
vessel in operable communication with the pressure vessel, at least
two motor-pump assemblies located within the pressure vessel, each
of the at least two motor-pump assemblies having a submersible
electric motor, and a submersible pump coupled to the submersible
electrical motor, wherein the submersible pump is configured to
pump fluid from within the pressure vessel to without the pressure
vessel.
[0007] Also disclosed herein are embodiments relating to a method
for pumping a fluid from a pressure vessel, the method including
supplying a fluid to a pressure vessel, pumping the fluid with two
or more submersible electric motor pumps located within the
pressure vessel, and discharging a pumped fluid from the pressure
vessel.
[0008] Also disclosed herein are embodiments relating to a method
for pumping a fluid from a pressure vessel, the method including
supplying power to two or more submersible electric motors located
within the pressure vessel, rotating a rotor located within each of
the two or more submersible electric motors, rotating two or more
pump shafts each of which are within a separate pump and each of
which are in operable communication with each of the rotors. The
method further includes pumping a fluid within the pressure vessel
with each of the pumps and discharging a pumped fluid from the
pressure vessel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Referring now to the figures, which are exemplary
embodiments and wherein like elements are numbered alike:
[0010] FIG. 1 is a sectional view of a known single pressure vessel
mounted submerged electric motor pump system;
[0011] FIG. 2 is a front view of the disclosed pressure vessel and
submerged electric motor pumps system;
[0012] FIG. 3 is a side view of the system shown in FIG. 2;
[0013] FIG. 4 is a side view of a system with a foot valve located
at the suction end of the pump; and,
[0014] FIG. 5 is a front view of the system shown in FIG. 4.
DETAILED DESCRIPTION
[0015] The disclosed pressure vessel mounted submerged electric
motor pump system comprises two or more pumps within one pressure
vessel. No other known pressure vessel pump system for cryogenic
liquefied gas has two or more pumps within one pressure vessel.
Advantages of having two or more pumps within one pressure vessel
is that suction piping and vent piping are simplified, and cost and
space required are reduced. Submerged electric motor pump systems
with two or more pumps within one pressure vessel will have a
smaller footprint than two or more pressure vessel and submerged
electric motor pump systems. This smaller footprint is especially
advantageous where space is at a premium, such as, but not limited
to, offshore platforms, and shipboard installations. Additionally,
since there is only one pressure vessel, as opposed to two or more
pressure vessels, there only needs to be one set of pressure vessel
piping, as opposed to two or more sets of pressure vessel suction
and vent piping, thus making for less complex and less costly
installation.
[0016] FIGS. 2 and 3 show two views of one embodiment of the
disclosed pressure vessel and submerged electric motor pump system
50. The pressure vessel 54 has a plurality of support columns 58,
62, 66, 72 each of which is configured to support a submersible
electric motor pump.
[0017] FIG. 3 shows a cut-away view through support column 58
enabling one to see the motor 108 and the pump 112. In this view,
it can be seen that the support column 58 is fastened to the
pressure vessel 54 as an extension of the pressure vessel 54. Thus
it is clear that as an extension of the pressure vessel 54, the
support column 58 is able to withstand the same internal fluid
pressures as the remainder of the pressure vessel 54. A head plate
116 may be attached to an end of the support column 58. The head
plate 116 provides access to the interior of the pressure vessel
54. The motor 108 comprises a sealed housing 110 and an electric
motor (not seen in this view) with a rotor (not seen in this view)
located within the housing 110. The motor housing 110 may be
attached and supported by the head plate 116. The pump 112
comprises a housing 114, a pump shaft (not seen in this view), and
impellers (not seen in this view). The motor housing 108 may be
attached to a head plate 116 of the support column 58. The pump
housing 114 may be attached to the motor housing 110. Within the
housings 110,114, the pump shaft is normally coupled to the rotor
of the electric motor. The coupling may be a flexible or rigid
coupling, but it is necessary to choose a coupling able to
withstand the particular conditions within the pressure vessel,
which may be extremely cold if cryogenic fluid is being pumped or
highly corrosive if certain corrosive fluids are being pumped. The
interior of the pressure vessel may include support struts 120 or
other means attached to the pump housing 114 in order to provide
lateral support to the pump 112. The methods of attachment for each
of the above structures may include bolting the structures
together, however, other methods may be used, including, but not
limited to: welding, using threaded fittings, using mating pieces,
such as, but not limited to: socket and post. The pressure vessel
54 may have support webs 124 to provide support and stabilization
to the support column 58. Although support webs 124 are shown, any
of a number of known support structures may be used.
[0018] Although only one motor-pump pair's configuration was
described above with respect to FIG. 3, the other motor pump pairs
within support columns 62, 66, 72 may be configured in the same or
similar way. However, there may be situations where the motor-pump
pairs for one or more of the support columns may be configured
differently than the other pairs, for instance if a different sized
pump or motor were installed.
[0019] The pump 112 shown in FIG. 3 is a vertical pump, however,
the pressure vessel and submerged electric motor pump system 50 may
be configured to house horizontal pumps, or pumps positioned at
some orientation other than vertical or horizontal, depending on
the user's requirements. Often times, floor space is a limiting
factor and a vertically oriented pump system typically has a
smaller footprint than a horizontally oriented pump system. It
should be noted that the pump 112 may be any of a number of types
of pumps, including, but not limited to: centrifugal pump, axial
flow pumps, screw pumps, reciprocating pumps, positive displacement
pumps and jet pumps.
[0020] Referring back to FIG. 2, the system may have four support
columns 58, 62, 66, 72. It should be clear however, that other
embodiments of the disclosed system may have as few as two
centrifugal pumps and up to "N" centrifugal pumps, where N is a
positive integer. The embodiment shown has two suction nozzles 76,
however other embodiments may have as few as one suction nozzle, or
three or more suction nozzles. The suction nozzles 76 may be
coupled to an external fluid supply, thereby providing fluid to the
interior of the pressure vessel 54, and ultimately to the inlet of
the pumps located within the pressure vessel 54. The pressure
vessel 54 may include one drain line 80 and at least one pressure
vessel vent line 84, although the embodiment shown has two pressure
vessel vent lines 84. The drain line 80 is coupleable to drain
piping located without the pressure vessel 54. Because there is
only one pressure vessel 54, there only needs to be one set of
suction, drain and vent lines routed to a separate suction and
phase separation vessel which would usually be mounted at a higher
elevation. The two or more pressure vessels can also be configured
to function as a phase separator which would eliminate the need for
a separate suction and phase separation vessel. Also, since there
is only one pressure vessel 54, only one mounting structure is
necessary for the disclosed pressure vessel and submerged electric
motor pump system 50.
[0021] Still referring to FIG. 2, each of the support columns 58,
62, 66, 72 may have a discharge line 88, and a vent line 92
extending therefrom which provides a means for fluid communication
from within the pressure vessel to without (that is, to the
exterior of) the pressure vessel. The discharge line 88 may be
coupleable to piping located outside the pressure vessel 54. The
piping located without the pressure vessel can transport the pumped
fluid to some location. The vent line 92 may also be configured to
be able to be coupled to a vent piping or vent system located
without the pressure vessel, in order to vent fluids and/or vapors
from the pumps located within the pressure vessel 54. Additionally,
each of the support columns 58, 62, 66, 72 may have an electrical
connection 96 extending therefrom. The electrical connections 96
may be coupleable to an external power source in order to provide
power to the electric motors located within the pressure vessel
54.
[0022] FIGS. 4 and 5 show another embodiment of the disclosed
system where one or more of the individual electric motor pump
systems may be removable from the pressure vessel 54, rather than
fixedly attached therein. FIG. 4 shows a cut-away view through one
motor 108 pump 112 pair, wherein each of the plurality of
centrifugal pumps inside the pressure vessel 54 may have a foot
valve 100 installed at the suction end 104 of the pump 112. FIG. 5
shows a front view of the removable pump installed within the
pressure vessel 54. While only one removable pump is shown in
detail within FIG. 5, it should be understood that any number of
the motor-pump pairs supported by the pressure vessel 54 may be
designed to be removable. Thus, it is within the scope of this
invention to have all of the pumps fixedly attached within the
pressure vessel 54, all of the pumps removably inserted within the
pressure vessel 54, or a subset of the pumps fixedly attached and a
subset of the pumps removably inserted. As most clearly shown in
FIG. 4, when the foot valve 100 is opened, fluid from the pressure
vessel 54 may enter the pump 112 and pump housing 114. When the
foot valve 100 is closed, fluid from the pressure vessel 54 cannot
enter the pump 112 or housing 114 and can be forced to leave the
pump housing 114 and return to the pressure vessel 54 by
pressurizing housing 114 with inert gas. This embodiment of
removable pumps, with a foot valve 100, facilitates pump
replacement of a single pump without taking the multi-pump vessel
out of service should a malfunction occur. The foot valve 100 may
be pre-loaded with pre-load devices 130. The pre-load devices may
be springs. Thus, when the weight of the motor 108 pump 112 pair is
lifted up, the pre-load devices 130 will automatically close the
foot valve 100. Thus, the individual pumps may be removable, and
may also include separate valves at each discharge 88, as well as
at each suction as described above, of the pumps for further
simplifying removal of an individual pump. The valves for
discharge, vent, and suction may be open when the pump is installed
and closed when the pump is removed. As shown in FIG. 5, the vents
92 may include valves 115 such that two adjacent pumps 112 may be
connected as shown in FIG. 2. These may be used to equalize the
liquid level in each pump column and assure that the pump is fully
submerged. The valve for each pump may be closed when the pump is
operating or when the pump is removed.
[0023] For the embodiments shown in FIGS. 4 and 5, the time
necessary to replace a single motor pump pair with a new pair is
dramatically reduced from what would otherwise be required. In some
cases the time savings is sufficient to such that a motor pump
replacement operation may be accomplished without requiring the
entire operation, of which the pump system is a part of, to be shut
down. This of course is desirable and therefore beneficial to users
and purchasers of such pump systems.
[0024] The disclosed pressure vessel and submerged electric motor
pump system takes up a smaller footprint than a comparable number
of one pump per pressure vessel systems coupled in parallel. The
disclosed pressure vessel and submerged electric motor pump system
requires fewer piping connections. Therefore the disclosed pressure
vessel and submerged electric motor pump system should be less
expensive than a comparable number of one pump per pressure vessel
systems coupled in parallel, and easier to install, service and
maintain.
[0025] The use of the terms first, second, etc. do not denote any
order or importance, but rather the terms first, second, etc. are
used to distinguish one element from another.
[0026] While the invention has been described with reference to
several embodiments, it will be understood by those skilled in the
art that various changes may be made and equivalents may be
substituted for elements thereof without departing from the scope
of the invention. In addition, many modifications may be made to
adapt a particular situation or material to the teachings of the
invention without departing from the essential scope thereof.
Therefore, it is intended that the invention not be limited to the
particular embodiments disclosed as the best mode contemplated for
carrying out this invention, but that the invention will include
all embodiments falling within the scope of the appended
claims.
* * * * *