U.S. patent number 3,741,298 [Application Number 05/143,787] was granted by the patent office on 1973-06-26 for multiple well pump assembly.
Invention is credited to Lawrence J. Canton.
United States Patent |
3,741,298 |
Canton |
June 26, 1973 |
**Please see images for:
( Certificate of Correction ) ** |
MULTIPLE WELL PUMP ASSEMBLY
Abstract
An adapter housing for mounting an auxiliary well pump in a bore
hole to supplement the production of, and act as a standby for, the
main well pump. The adapter housing is mounted above the main pump
in the bore hole and comprises an elongate tubular member having a
diameter preferably no greater than that of the main pump. Inside
the housing are a longitudinal chamber for mounting an auxiliary
pump smaller than the main pump and a longitudinal bypass portion
for conducting fluid under pressure upward from the main pump. The
lower end of the housing is coupled with the discharge port at the
top of the main pump, and the upper end of the housing is coupled
with the well discharge pipe which extends to the ground surface.
The two ends of the housing communicate through the bypass portion
to form a continuous conduit from the main pump to the surface. The
auxiliary pump chamber runs almost the entire length of the housing
and has a cross section smaller than that of the housing to allow
room for the bypass portion. The chamber is completely sealed from
the bypass portion but is exposed to the surrounding well fluid by
means of a window in the side of the housing. The small auxiliary
pump mounted within the chamber draws fluid through the window and
discharges it under pressure through a discharge port into the
bypass portion of the housing. There the fluid mixes with and
supplements the fluid discharged by the main pump, and the combined
discharge of the two pumps is conducted by pump pressure to the
ground surface, through the well discharge pipe. The interior of
the bypass portion of the housing is provided with streamlined
surfaces to minimize turbulence and is coated with a suitable
material to reduce flow friction and resist corrosion. Power means
are provided for running both pumps simultaneously to augment
production for peak flow requirements, or alternatively for running
each pump separately when lower volume is required or when one of
the pumps breaks down.
Inventors: |
Canton; Lawrence J. (Vancouver,
WA) |
Family
ID: |
22505633 |
Appl.
No.: |
05/143,787 |
Filed: |
May 17, 1971 |
Current U.S.
Class: |
166/105;
137/565.33; 417/62; 417/426 |
Current CPC
Class: |
E21B
43/128 (20130101); Y10T 137/86163 (20150401) |
Current International
Class: |
E21B
43/12 (20060101); E21b 043/00 () |
Field of
Search: |
;166/105,65R
;417/62,201,203,205,426 ;137/567 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Leppink; James A.
Claims
What is claimed is:
1. A well pump adapter housing for mounting an auxiliary pump above
a main pump in a well bore hole and conducting the fluid discharged
from both pumps into a well discharge pipe comprising:
a. an elongate shell having an inlet port adjacent its bottom end
for coupling with the discharge conduit of said main pump, a
discharge port adjacent its upper end for coupling with said well
discharge pipe, and a passageway between the exterior and interior
of said shell;
b. wall means within said shell for dividing its interior into two
portions sealed from one another to prevent the passage of fluid
therebetween;
c. one of said portions comprising a chamber for housing said
auxiliary pump exposed to the exterior of said shell through said
passageway;
d. the other said portion comprising a longitudinal bypass conduit
circumventing said chamber and connecting said inlet port and
discharge port of said shell for conducting the fluid discharged by
said main pump toward said well discharge pipe; and
e. auxiliary pump discharge conduit means coupled with said
auxiliary pump for conducting the fluid discharged by said
auxiliary pump toward said well discharge pipe.
2. The adapter housing of claim 1 wherein said auxiliary pump
conduit means penetrates through said wall means into said bypass
circuit.
3. The adapter housing of claim 1 comprising a tubular shell having
an opening in one side thereof and an elongate channel member
therein, said channel member being of a width and depth smaller
than the inside diameter of said tubular shell and fitting within
said shell with its concave side exposed to said opening, said
concave side of said channel member forming said chamber for
mounting said auxiliary pump and the portion between the convex
side of said channel member and the interior of said shell forming
said bypass conduit.
4. The adapter housing of claim 3 wherein said main pump is
generally cylindrical in shape and wherein said tubular shell has
an outside diameter no greater than the outside diameter of said
main pump.
5. The adapter housing of claim 1 wherein the side of said wall
means facing the interior of said bypass conduit includes
streamlining means for minimizing turbulence with respect to fluid
discharged through said bypass conduit.
6. The adapter housing of claim 1 wherein the portions of said
shell and wall means facing the interior of said bypass conduit are
coated with a layer of material for minimizing pipe friction
pressure losses with respect to fluid discharged through said
bypass conduit and for resisting corrosion.
7. A well pump assembly for drawing underground fluid and pumping
the fluid through a well bore hole toward ground level
comprising:
a. a first pump housed within said bore hole having a cross-section
transverse to said bore hole;
b. a second pump housed in said bore hole at a higher elevation
than said first pump and having a cross section transverse to said
bore hole smaller in area than said cross section of said first
pump;
c. bypass conduit means sealed from the intake of said second pump
for conducting fluid discharged from said first pump upwardly past
said second pump in side-by-side relation with the latter; and
d. conduit means for joining the fluid discharged from said second
pump with said fluid discharged from said first pump.
8. The well pump assembly of claim 7 wherein the cross sectional
area of said bypass conduit means transverse to said bore hole is
sufficiently small that, when added to the corresponding
side-by-side transverse cross sectional area of said second pump,
the total area of the combined said cross sections is no larger
than the transverse cross-sectional area of said first pump.
9. The well pump assembly of claim 7 wherein the greatest outside
transverse width of said first pump is at least as large as the
greatest outside transverse width of said second pump and bypass
conduit assembly taken together.
10. A well pump assembly for drawing fluid from an underground
fluid source and pumping the fluid through a well bore hole toward
ground level comprising:
a. a main pump means and an auxiliary pump means, each comprising a
vertically elongate pump member, both housed in said bore hole with
their discharge ends connected by fluid conduit means with a common
well discharge pipe for pumping said fluid from said fluid source
through said well discharge pipe, said auxiliary pump means being
mounted vertically above said main pump means and having a
discharge flow rate capacity and a transverse cross sectional area
less than that of said main pump means;
b. power source means selectively coupled with said pair of pump
means and operable, in a first selective mode, for driving said
main pump means to produce a relatively high discharge flow rate of
said fluid through said discharge pipe and operable, in a second
selective mode, for driving said auxiliary pump means without
thereby driving said main pump means to produce a lower discharge
flow rate of said fluid through said discharge pipe; and
c. a bypass conduit for conducting fluid discharged from said main
pump means upwardly past said auxiliary pump means in side-by-side
relation therewith.
11. The well pump assembly of claim 10 wherein said selectively
coupled power source means is operable, in said first selective
mode, for driving said main pump means without thereby driving said
auxiliary pump means to produce said relatively high discharge flow
rate of said fluid.
12. The well pump assembly of claim 11 wherein said selectively
coupled power source means is operable, in a third selective mode,
for driving said main pump means and said auxiliary pump means
simultaneously to produce a total discharge flow rate of said fluid
greater than the flow rates obtainable from either said main or
auxiliary pump means individually.
13. The well pump assembly of claim 10 wherein said selectively
coupled power source means is operable, in said first selective
mode, for driving said main pump means and said auxiliary pump
means simultaneously to produce said relatively high discharge flow
rate of said fluid.
14. The well pump assembly of claim 10 wherein said main pump
member is generally cylindrical in shape and wherein said auxiliary
pump member and said by-pass conduit are housed within a tubular
member having an outside diameter no larger than that of said main
pump member.
Description
BACKGROUND OF THE INVENTION
This invention relates to improvements in well pump assemblies of
the type where multiple pumps are positioned one above the other in
a well bore hole, and conduit means are provided in the bore hole
for conducting the fluid discharged by the pumps to the ground
surface. More specifically, the pump assembly is of the type
particularly adaptable for use in water wells where the pumps draw
from the same fluid source and supplement one another's flow
production.
Well pump assemblies of the type commonly used in water wells
usually consist of a single elongate cylindrical pump, normally
electrically powered, immersed in water at the bottom of the well
bore hole. The volumetric flow capacity of the pump under given
discharge pressure and depth conditions depends on its diameter,
horsepower rating and number of stages, greater diameters and
horsepower rating and fewer stages generally corresponding to
greater flow capacity. The size of pump required is determined by
the estimated peak flow demands which may occur during the year.
Pump size is also determined by the well bore diameter, which must
be of sufficient size to house a pump capable of satisfying such
peak flow demands.
The drawbacks of this common approach to water well pump design are
threefold. First, the provision of only one pump in the bore hole
does not provide any emergency or standby pumping capacity if the
pump should fail. Such failure, for only 1 day's time, might for
example cause a dairyman the loss of an entire day's milk crop. The
dairyman might, for emergency requirements, drill a separate bore
hole for a second pump, but this would be inordinately
expensive.
Second, the size of the pump and bore hole are determined by peak
flow requirements which may typically arise only three or four
times a year during periods of high irrigation demand. The high
cost of providing a large enough pump and bore hole to satisfy
these peak flow demands must be borne even though normal everyday
volume requirements are much lower and require a substantially
smaller pump and bore hole.
Third, a pump large enough to satisfy peak flow demands is not
particularly efficient for satisfying everyday low flow demands,
requiring costly excess power to do so. Moreover, a high flow
capacity pump can be allowed to run only for short periods of time
when small flow volumes are required, and such intermittent
operation can be harmful to the pump and shorten its useful
life.
Multiple well pump assemblies have on occasion been utilized in a
single well bore hole in an attempt to overcome the above-mentioned
difficulties. These prior art arrangements comprise two pumps of
the same size and flow capacity positioned one above the other,
immersed in water at the bottom of the bore hole. The pumps are
plumbed in parallel to discharge into a common well discharge pipe
and are individually actuated for low flow demands and jointly
actuated for high flow demands. These systems do overcome several
of the disadvantages inherent in the single pump assemblies
inasmuch as one pump can act as a standby or emergency pump if the
other breaks down, and only one pump need be actuated to satisfy
small flow requirements while both may be run simultaneously for
peak flow requirements. However, these assemblies require parallel
plumbing which is difficult and expensive to install. Moreover, the
additional plumbing causes operational problems not found in single
pump assemblies by introducing turbulence and pipe friction
pressure losses, particularly in the regions of the elbows and tees
commonly utilized in such plumbing. These pressure losses tend to
reduce the flow capacity of the pump assembly.
Furthermore, the expense of drilling an excessively large bore hole
is not overcome by the multiple pump assemblies of the prior art,
even though smaller diameter pumps can be used in combination for
peak requirements. This results from the fact that a conduit must
be provided bypassing the upper pump to conduct fluid discharged by
the lower pump. Since both pumps are of the same diameter, the
bypass circuit creates a "bulge" in the pump assembly adjacent the
upper pump. This requires that the bore hole be of sufficient
diameter to house the "bulge", which necessitates the provision of
a hole diameter greater than that otherwise required merely to
house the pumps themselves. Many existing wells do not have bore
holes of sufficient diameter to accommodate such a "bulge".
SUMMARY OF THE PRESENT INVENTION
The present invention is directed to a multiple well pump assembly
of the general type described in which upper and lower pumps are
both housed in a single well bore hole and the pumps are connected
in parallel so as to supplement each other's output. The upper
pump, which is smaller in diameter and has a flow capacity less
than the lower pump, is mounted in a prefabricated tubular adapter
housing preferably having a diameter no greater than the diameter
of the lower pump. The housing is positioned above the lower pump
and contains a chamber exposed to the surrounding well water for
mounting the upper pump, together with a conduit portion bypassing
the chamber and coupled to the discharge end of the lower pump.
Both pumps discharge into the bypass circuit of the housing where
their fluid outputs mix with and supplement each other. The
combined discharge of the two pumps is conducted to the ground
surface through a well discharge pipe connected to the upper end of
the housing. The interior of the bypass portion is provided with
streamlined surfaces to reduce turbulence and is coated with a
suitable material to minimize flow friction and resist corrosion.
Power means are provided for running both pumps simultaneously to
augment production for peak flow requirements, or alternatively for
running each one separately when lower volume is required or when
one of the pumps breaks down.
The combination of features contained in the well pump assembly of
the present invention provide it with several important advantages
not found in well pump assemblies of the prior art, with respect to
both initial installation and operation. First, the presence of two
pumps supplementing each other and producing a peak flow rate equal
to the sum of their individual discharge flow rates provides a
substantial reduction in the diametric size of the pump means
needed to satisfy peak flow demands, which in turn reduces the size
of the bore hole diameter required. More importantly, the bore hole
size is further minimized by the fact that the upper pump of the
present invention has a smaller diameter than the lower pump and
thus provides room for a bypass conduit without thereby creating a
"bulge" adjacent the upper pump as is found in prior art upper and
lower pump assemblies. Accordingly, the adapter housing need be no
larger than the lower pump, and the bore hole therefore need only
be large enough to house the lower pump. This advantage is
particularly critical when it is desired to modify an existing well
to increase output capacity, provide a standby pump, and supply
multiple flow rates. The assembly of the present invention can
accomplish this without need for enlarging the bore hole or well
casing since the hole is already large enough to house the lower
pump and therefore large enough to receive the adapter housing.
Second, the provision of a prefabricated upper pump housing having
an integral bypass conduit for the lower pump and a mounting
chamber for the upper pump, readily installable merely by coupling
the housing with the discharge end of the lower pump without the
need for any other plumbing, allows rapid, simple and inexpensive
installation and removal.
Third, the provision of streamlined and coated surfaces within the
bypass conduit of the housing minimizes the pressure losses in the
fluid produced by the two pumps by reducing flow friction and
turbulence below the levels encountered with prior art multiple
pump devices.
Fourth, the provision of two pumps having different flow capacities
coupled with power means for running each pump individually or both
simultaneously provides a well pump system capable of selectively
delivering three different effective flow rates from a single well
bore hole to satisfy varying flow demands.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation view of the well pump assembly installed
in a well casing, with portions of the casing cut away to expose
the elements of the assembly.
FIG. 2 is an enlarged extended detail view of a portion of the
assembly taken along line 2--2 of FIG. 1, with the casing and
portions of the assembly cut away to show inner parts.
FIG. 3 is a top sectional view of the assembly taken along lines
3--3 of FIG. 2.
FIG. 4 is a bottom sectional view taken along line 4--4 of FIG.
2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The well pump assembly, designated generally as 10 in FIG. 1,
comprises a main pump 12 and an auxiliary pump adapter housing 12
containing an auxiliary pump 14 mounted above the main pump 12. The
entire pump assembly is mounted in a well bore hole lined with a
conventional tubular well casing 18, the interior of which is
exposed to the surrounding well fluid. Both main pump 12 and
auxiliary pump 14 are positioned below the level of the water or
other fluid within casing 18.
Main pump 12 and auxiliary pump 14 are conventional, electrically
powered submersible turbine pumps of the type for example
manufactured by Fairbanks Morse of Kansas City, Kans. The main pump
12 is of elongate, generally cylindrical shape with a series of
rotary impellers 22 driven by an electric motor 20. Impellers 22
draw the surrounding well fluid from the interior of casing 18
through intake strainer 24 and discharge the fluid under pressure
through threaded discharge conduit 26. Auxiliary pump 14 is similar
in construction having electric motor 28 and impellers 30 which
draw surrounding fluid through intake strainer 32 and discharges it
through discharge conduit 34.
Each of the pump motors is connected to a source of electrical
power through waterproof electrical cable 36 which contains a
separate set of leads 37, 37a respectively for each pump. Each set
of leads is coupled with a separate electrical switch 39, 39a
respectively at ground level operable either to conduct or
interrupt the flow of electrical current to each pump individually.
Thus, with a single switch in the closed position only the pump
coupled with that switch is driven, while with both switches in the
closed position both pumps are driven simultaneously.
The discharge conduits of main pump 12 and auxiliary pump 14 are
connected in parallel by fluid passageways so as to discharge into
a common well discharge pipe 38 which extends to ground level. This
parallel plumbing, plus the means for mounting auxiliary pump 14
between main pump 12 and well discharge pipe 38, is provided by a
novel auxiliary pump adapter housing 16 which will now be described
in detail.
Adapter housing 16, as best seen in FIG. 2, comprises an elongate
tubular shell 40 with a threaded inlet port 42 at its bottom end
for coupling with the threaded discharge conduit 26 of main pump
12, and a discharge port 44 at its upper end for coupling with the
well discharge pipe 38. The shell 40 also contains an elongate
opening or window 46 in one side of the shell forming a passageway
between its exterior and interior.
Inside the shell is a wall assembly comprising upper streamlining
member 48, U-shaped channel member 50 and lower streamlining member
52 which are sealingly joined with each other and with the interior
of shell 40, as for example by welding, so as to divide the
interior of the shell into two portions. The channel member 50 is
of smaller width and depth than the diameter of shell 40 and has an
upper end plate 54 sealing its upper end and a lower streamlining
portion 56 sealing its lower end. Both plate 54 and streamlining
portion 56 have flat edges 54a and 56a respectively, as best seen
in FIGS. 3 and 4. Streamlining members 48 and 52 have flat sides
48a and 52a respectively which mate with and are sealingly joined
with edges 54a and 56a respectively to form a continuously sealed
wall. The pair of longitudinal edges 50a of channel member 50 are
sealingly joined along their entire length with the inside surface
of shell 40 and encompass the longitudinal edges of opening 46 so
as to expose the concave side of channel member 50 to the opening
while sealing its convex side from the opening. The sealing of the
wall assembly with the interior of shell 40 is completed at the
juncture of peripheral edges 48b and 52b of streamlining members 48
and 52 respectively (FIG. 2) with the inner surface of shell
40.
From the above description of the wall assembly and the manner in
which its components are sealingly joined with one another and with
the interior of the shell, it is seen that the wall assembly seals
the two interior portions of the shell from one another so as to
prevent the passage of fluid between them. The portion exposed to
opening 46 in the side of the shell and formed by the concave side
of channel member 50 comprises a chamber 58 for housing auxiliary
pump 14. The other portion comprises a longitudinal bypass conduit
60 which circumvents chamber 58 and connects inlet port 42 with
discharge port 44 through their sealed junctures with streamlining
portions 52 and 48 respectively.
Shell 40 has an outside diameter and a transverse cross sectional
area preferably no larger than the outside diameter and transverse
cross sectional area, respectively, of main pump 12 so as not to
require a casing or bore hole larger than that necessary to house
main pump 12. Since both bypass conduit 60 and auxiliary pump 14
are housed within shell 40, pump 14 has a smaller transverse cross
section and a smaller diameter than that of main pump 12. This is
convenient since it is desirable that auxiliary pump 14 also have a
discharge flow rate capacity less than that of main pump 12 to
provide a choice of flow rates from the well in a manner to be
explained hereafter.
Auxiliary pump 14 is mounted within chamber 58 with its discharge
conduit 34 sealingly joined with and penetrating through upper end
plate 54 of channel member 50. Chamber 58 is exposed to the
surrounding well water in casing 18 by virtue of opening 46,
enabling pump 14 to draw from the surrounding fluid and discharge
through upper end plate 54 into bypass conduit 60. Since bypass
conduit 60 is also coupled with discharge conduit 26 of main pump
12 via inlet port 42, the discharge ends of the two pumps are
connected in parallel for emptying into discharge pipe 38 via
discharge port 44. This plumbing arrangement, together with the
aforementioned electrical switches which control the pumps, enables
either pump to be actuated separately to discharge at their
respective different flow rates into discharge pipe 38 or,
alternatively, to be actuated simultaneously to discharge jointly
into pipe 38 to produce a third flow rate greater than the
individual flow rates obtainable from either pump individually.
Thus, during periods of high irrigation demand, it might be
desirable to drive both pumps simultaneously to achieve the highest
flow rate possible. At other times, for example when washing a
barn, a somewhat lesser but still substantial flow rate might be
desired in which case main pump 12 alone might be actuated. At
still other times, when water is needed only for low volume
domestic uses, auxiliary pump 14 alone might be actuated. In each
case the pump system would be delivering fluid at a rate consistent
with its most efficient and economic capacity, thus helping to
conserve power and lengthen pump life.
Housing 16 is provided with several internal features designed to
maximize the flow rate of fluid discharged by pumps 12 and 14 by
minimizing pressure losses incident to such flow. For example
channel member 50 is provided with a lower streamlining portion 56
in the shape of a flattened cone with its pointed end facing inlet
port 42. Streamlining portion 46 reduces the turbulence and
consequent pressure loss which might otherwise result from the
directional deviation of flow through bypass conduit 60 caused by
the protrusion of auxiliary pump chamber 58 into the bypass
conduit. Moreover, upper and lower streamlining members 48 and 52,
each formed in the shape of a flattened truncated cone, minimize
the turbulence which might otherwise be caused by the change in
conduit cross section at the inlet and discharge ports 42 and 44 of
housing 16.
In addition, the interior surfaces of bypass conduit 60 are
preferably coated with a suitable material such as PVC (polyvinyl
chloride) or Teflon (polytetrafluorethylene) to reduce pipe
friction pressure losses in the conduit and, at the same time, help
to resist corrosion.
It should be noted that the flattened sides of upper streamlining
member 48 and lower streamlining member 52 respectively provide a
pair of cavities 62 and 64 within shell 40 through which electrical
cable 36 can be threaded for connection with pumps 12 and 14. This
ensures that the cable is protected by shell 40 and that no
additional space for the cable within the well casing is required
exterior of shell 40.
The terms and expressions which have been employed in the foregoing
abstract and specification are used therein as terms of description
and not of limitation, and there is no intention, in the use of
such terms and expressions, of excluding equivalents of the
features shown and described or portions thereof, it being
recognized that the scope of the invention is defined and limited
only by the claims which follow.
* * * * *