U.S. patent number 3,923,099 [Application Number 05/562,995] was granted by the patent office on 1975-12-02 for methods of well completion or workover of fluid containing subsurface formations.
This patent grant is currently assigned to Orpha B. Brandon. Invention is credited to Clarence W. Brandon.
United States Patent |
3,923,099 |
Brandon |
December 2, 1975 |
Methods of well completion or workover of fluid containing
subsurface formations
Abstract
The invention relates to well completion or workover of fluid
containing subsurface formations by packing off that portion of the
well bore adjacent the fluid containing formation from the well
bore above this formation and thereafter creating a low pressure
void in the packed off portion so as to cause a surge of fluid from
the formation into the created low pressure void. This low pressure
void impressed upon the fluid containing subsurface formation may
be utilized as a source of seismic energy for delineating the type
of fluid or formation existing in the subsurface formations
adjacent to or surrounding the well bore.
Inventors: |
Brandon; Clarence W.
(Nashville, TN) |
Assignee: |
Brandon; Orpha B. (Nashville,
TN)
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Family
ID: |
26998764 |
Appl.
No.: |
05/562,995 |
Filed: |
March 27, 1975 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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355239 |
Apr 30, 1973 |
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557273 |
Jun 13, 1966 |
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853405 |
Nov 16, 1959 |
3255820 |
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665995 |
Jun 17, 1957 |
3302720 |
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296038 |
Jun 27, 1952 |
2866509 |
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241647 |
Aug 31, 1951 |
2796129 |
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Current U.S.
Class: |
166/249; 166/281;
166/307; 166/308.1; 166/286; 166/250.01 |
Current CPC
Class: |
E21B
43/263 (20130101); E21B 37/10 (20130101) |
Current International
Class: |
E21B
37/10 (20060101); E21B 37/00 (20060101); E21B
43/263 (20060101); E21B 43/25 (20060101); E21B
033/13 (); E21B 043/26 (); E21B 043/27 () |
Field of
Search: |
;166/249,250,307,308,285,286,281,299,177,256,268 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Novosad; Stephen J.
Parent Case Text
CROSS-REFERENCES TO RELATED APPLICATIONS
This is a continuation-in-part of application Ser. No. 355,239
filed Apr. 30, 1973, now abandoned, which is a continuation of Ser.
No. 557,273 filed June 13, 1966, now abandoned, which is a
continuation-in-part of application Ser. No. 853,405 filed Nov. 16,
1959, now U.S. Pat. No. 3,255,820, and application Ser. No. 665,995
filed June 17, 1957, now U.S. Pat. No. 3,302,720, which in turn is
a continuation-in-part of application Ser. No. 296,038 filed June
27, 1952, now U.S. Pat. No. 2,866,509, and application Ser. No.
241,647 filed Aug. 13, 1951, now U.S. Pat. No. 2,796,129.
Claims
What I claim is:
1. A method of well completion or workover of oil, gas or other
fluid containing subsurface formations into which a well bore has
been drilled, which comprises the step of
packing off said fluid containing subsurface formation from said
well bore which is above said subsurface formation while providing
controllable communication through tubing between said fluid
containing formation and a wellhead at the surface of said well
bore,
thereafter creating substantially instantaneously at least once a
low pressure void or zone of rarefaction in that portion of the
well bore which is in communication with said fluid containing
subsurface formation but beneath said controlled communication in
said tubing, and
creating a negative fluid pulse or surge of fluid from said
subsurface formation into said created low pressure void or zone of
rarefaction in said packed off portion of said well bore that is in
communication with said fluid containing formation.
2. The method of claim 1 wherein said well bore has a casing or
liner which is cemented through said fluid containing subsurface
formation, comprising the additional step of packing off said
cemented casing or liner above said fluid containing formation,
providing communication between said lower packed off portion of
said well bore and said fluid containing formation by perforating
through said casing or liner.
3. The method of claim 2 including testing the production of fluid
from said subsurface formation through said tubing having
controlled communication with said wellhead at the top of said well
bore.
4. The method of claim 3 inlcuding testing the production of fluid
from said subsurface formation, and
cementing or plugging through said tubing from said wellhead
perforations producing undesired fluids.
5. The method of claim 1 including following said negative pulse or
surge of fluid from said subsurface formation into said packed off
portion of said well bore by an injection of fluid into said fluid
containing formation through said tubing having controlled
communication with said wellhead at the top of said well bore.
6. The method of claim 5 wherein said injected fluid is inclusive
of gases, solvents or emulsions.
7. The method of claim 5 wherein said injected fluid is a gas or
solvent.
8. The method of claim 5 including thereafter testing production of
fluid from said subsurface formation through said tubing having
controlled communication with said wellhead at the top of said well
bore.
9. The method of claim 1 wherein said fluid containing formation is
fractured by establishing formation fluid pressures up to or near
the formation breakdown pressure in said packed off lower portion
of said well bore which is in communication with said fluid
containing formation prior to said creating of said negative pulse
or low pressure void by the injecting of fluids at said wellhead
through said tubing having controlled communication with said fluid
containing formation.
10. The method of claim 9 wherein said established formation fluid
pressures have included therein gases.
11. The method of claim 9 wherein said formation fluid pressures
are created by pressurized gases, solvents or emulsions.
12. The method of claim 9 including the further step of injecting
additional fracturing fluids into said formation following said
negative pulse or surge of fluid from said subsurface formation
into said lower packed off portion of said well bore through said
tubing from said wellhead.
13. The method of claim 12 wherein said additionally injected fluid
is inclusive of gases, solvents or emulsions.
14. The method of claim 12 wherein said additionally injected fluid
is a gas or solvent.
15. The method of claim 12 including thereafter testing production
of fluid from said subsurface formation through said tubing having
said controlled communication with said wellhead at the top of said
well bore.
16. A method of well completion or workover of oil, gas or other
fluid containing subsurface formations into which a well bore has
been drilled, which comprises the step of
packing off said fluid containing subsurface formation from said
well bore which is above said subsurface formation,
thereafter creating substantially instantaneously a low pressure
void or zone of rarefaction in that portion of the well bore which
is in communication with said fluid containing subsurface
formation, and
creating a negative fluid pulse or surge of fluid from said
substrate formation into said created low pressure void or zone of
rarefaction in said packed off portion of said well bore that is in
communication with said fluid containing formation,
including following said negative pulse or surge of fluid from said
subsurface formation into said packed off portion of said well bore
by an injection of fluid into said fluid containing subsurface
formation,
wherein said injected fluid is inclusive of an acidizing agent or
corrosion inhibitor.
17. A method of well completion or workover of oil, gas or other
fluid containing subsurface formations into which a well bore has
been drilled, which comprises the step of
packing off said fluid containing subsurface formation from said
well bore which is above said subsurface formation,
thereafter creating substantially instantaneously a low pressure
void or zone of rarefaction in that portion of the well bore which
is in communication with said fluid containing subsurface
formation, and
creating a negative fluid pulse or surge of fluid from said
substrate formation into said created low pressure void or zone of
rarefaction in said packed off portion of said well bore that is in
communication with said fluid containing formation,
including following said negative pulse or surge of fluid from said
subsurface formation into said packed off portion of said well bore
by an injection of fluid into said fluid containing subsurface
formation,
wherein said injected fluid is heated prior to its injection.
18. A method of well completion or workover of oil, gas or other
fluid containing subsurface formations into which a well bore has
been drilled, which comprises the step of
packing off said fluid containing subsurface formation from said
well bore which is above said subsurface formation,
thereafter creating substantially instantaneously a low pressure
void or zone of rarefaction in that portion of the well bore which
is in communication with said fluid containing subsurface
formation, and
creating a negative fluid pulse or surge of fluid from said
subsurface formation into said created low pressure void or zone of
rarefaction in said packed off portion of said well bore that is in
communication with said fluid containing formation,
including following said negative pulse or surge of fluid from said
subsurface formation into said packed off portion of said well bore
by an injection of fluid into said fluid containing subsurface
formation,
wherein said injected fluid is a formation cementing or plugging
agent.
19. A method of well completion or workover of oil, gas or other
fluid containing subsurface formation into which is well bore has
been drilled, which comprises the step of
packing off said fluid containing subsurface formation from said
well bore which is above said subsurface formation,
thereafter creating substantially instantaneously a low pressure
void or zone of rarefaction in that portion of the well bore which
is in communication with said fluid containing subsurface
formation, and
creating a negative fluid pulse or surge of fluid from said
subsurface formation into said created low pressure void or zone of
rarefaction in said packed off portion of said well bore that is in
communication with said fluid containing formation,
wherein said fluid containing formation is fractured by
establishing formation fluid pressure up to or near the formation
breakdown pressure in said packed off lower portion of said well
bore which is in communication with said fluid containing formation
prior to said creating of said negative pulse or low pressure
void,
including the further step of injecting additional fracturing
fluids into said formation following said negative pulse or surge
of fluid from said subsurface formation into said lower packed off
portion of said well bore,
wherein said additional fracturing fluids are inclusive of an
acidizing agent.
20. A method of well completion or workover of oil, gas or other
fluid containing subsurface formations into which a well bore has
been drilled, which comprises the step of
packing off said fluid containing subsurface formation from said
well bore which is above said subsurface formation,
thereafter creating substantially instantaneously a low pressure
void or zone of rarefaction in that portion of the well bore which
is in communication with said fluid containing subsurface
formation, and
creating a negative fluid pulse or surge of fluid from said
subsurface formation into said created low pressure void or zone of
rarefaction in said packed off portion of said well bore that is in
communication with said fluid containing formation,
wherein said fluid containing formation is fractured by
establishing formation fluid pressure up to or near the formation
breakdown pressure in said packed off lower portion of said well
bore which is in communication with said fluid containing formation
prior to said creating of said negative pulse or low pressure
void,
including the further step of injecting additional fracturing
fluids into said formation following said negative pulse or surge
of fluid from said subsurface formation into said lower packed off
portion of said well bore, and
thereafter testing production of fluid from said subsurface
formation, and
following said testing by cementing or plugging off undesired fluid
production from said fluid containing formation.
21. A method of well completion or workover of oil, gas or other
fluid containing subsurface formations into which a well bore has
been drilled, which comprises the step of
packing off said fluid containing subsurface formation from said
well bore which is above said subsurface formation,
thereafter creating substantially instantaneously a low pressure
void or zone of rarefaction in that portion of the well bore which
is in communication with said fluid containing subsurface
formation, and
creating a negative fluid pulse or surge of fluid from said
subsurface formation into said created low pressure void or zone of
rarefaction in said packed off portion of said well bore that is in
communication with said fluid containing formation,
including following said negative pulse or surge of fluid from said
subsurface formation into said packed off portion of said well bore
by an injection of fluid into said fluid containing subsurface
formation,
thereafter testing production of fluid from said subsurface
formation, and
following said testing by cementing or plugging off undesired fluid
production from said fluid containing formation.
22. A method of well completion or workover of oil, gas or other
fluid containing subsurface formations into which a well bore has
been drilled, which comprises the step of
packing off said fluid containing subsurface formation from said
well bore which is above said subsurface formation,
thereafter creating substantially instantaneously a low pressure
void or zone of rarefaction in that portion of the well bore which
is in communication with said fluid containing subsurface
formation, and
creating a negative fluid pulse or surge of fluid from said
subsurface formation into said created low pressure void or zone of
rarefaction in said packed off portion of said well bore that is in
communication with said fluid containing formation,
wherein said low pressure void or zone of rarefaction is occasioned
by a sonic wave generator, pump or compressor operated by a
separate power source which imposes sonic waves or an increase of
fluid pressure upon fluid contained in said well bore above said
packed off lower portion of said well bore which is in
communication with said fluid containing formation.
23. The method of claim 22 wherein fluid contained in said well
bore above said packed off portion thereof includes an acidizing
agent and said operation by said separate power source allows the
injection of said agent into said fluid containing formation
following said creating of said negative pulse or surge of fluid
from said subsurface formation.
24. The method of claim 22 wherein fluid contained in said well
bore above said packed off portion thereof includes or consists of
gases or solvents and said operation by said separate power source
allows the injection of said fluid into said fluid containing
formation following said creation of said negative pulse or surge
of fluid from said subsurface formation.
25. The method of claim 22 wherein fluid contained in said well
bore above said packed off portion thereof is a formation
pressuring fluid and said operation by said separate power source
allows the injection of said formation pressuring fluid into said
subsurface formation following said creation of said negative pulse
or surge of fluid from said formation.
26. The method of claim 22 including thereafter testing production
of fluid from said subsurface formation.
27. The method of claim 22 including thereafter testing production
of fluid from said subsurface formation, and following said testing
by cementing or plugging off undesired fluid production from said
fluid containing formation.
28. The method of claim 22 wherein said fluid containing formation
is fractured by establishing formation fluid pressures up to or
near the formation breakdown pressure in said packed off lower
portion of said well bore which is in communication with said fluid
containing formation prior to said creating of said negative pulse
or low pressure void.
29. The method of claim 28 including the further step of injecting
additional fracturing fluids into said formation following said
negative pulse or surge of fluid from said subsurface formation
into said lower packed off portion of said well bore.
30. The method of claim 29 including thereafter testing production
of fluid from said subsurface formation.
31. The method of claim 29 including thereafter testing production
of fluid from said subsurface formation, and
following said testing by cementing or plugging off undesired fluid
production from said fluid containing formation.
32. A method of well completion or workover of oil, gas or other
fluid containing subsurface formations into which a well bore has
been drilled, which comprises the step of
packing off said fluid containing subsurface formation from said
well bore which is above said subsurface formation,
thereafter creating substantially instantaneously a low pressure
void or zone of rarefaction in that portion of the well bore which
is in communication with said fluid containing subsurface
formation, and
creating a negative fluid pulse or surge of fluid from said
subsurface formation into said created low pressure void or zone of
rarefaction in said packed off portion of said well bore that is in
communication with said fluid containing formation,
wherein said creation of said low pressure void or zone of
rarefaction becomes a source of seismic energy within said
subsurface formation, and
wherein said source of seismic energy following its creation is
recorded at adjacent well bores to indicate the type of fluid or
formation existing between said source of seismic energy and said
adjacent well bores.
33. The method of claim 32 wherein said low pressure void or zone
of rarefaction is occasioned by a sonic wave generator, pump or
compressor operated by a separate power source which imposes sonic
waves or an increase of fluid pressure upon fluid contained in said
well bore above said packed off lower portion of said well bore
which is in communication with said fluid containing formation.
34. The method of claim 32 wherein said low pressure void or zone
of rarefaction comprises a substantially instantaneous rarefaction
or cavitational modulation imposed on a sonic wave in said fluid in
said lower packed off portion of said well bore which is in
communication with said fluid containing formation.
35. The method of claim 34 including varying the phase angle of
said rarefaction or cavitational modulation in relation to said
sonic wave, producing recognizable variations in said seismic
energy recorded at said adjacent well bores.
36. A method of well completion or workover of oil, gas or other
fluid containing subsurface formations into which a well bore has
been drilled, which comprises the step of
packing off said fluid containing subsurface formation from said
well bore which is above said subsurface formation,
thereafter creating substantially instantaneously a low pressure
void or zone of rarefaction in that portion of the well bore which
is in communication with said fluid containing subsurface
formation, and
creating a negative fluid pulse or surge of fluid from said
subsurface formation into said created low pressure void or zone of
rarefaction in said packed off portion of said well bore that is in
communication with said fluid containing formation,
wherein said creation of said low pressure void or zone of
rarefaction becomes a source of seismic energy within said
subsurface formation, and
wherein said source of seismic energy following its creation is
recorded at the surface surrounding said well bore or at said well
bore to indicate the type of fluid or formation existing in the
subsurface formation.
37. The method of claim 36, wherein said low pressure void or zone
of rarefaction is occasioned by a sonic wave generator, pump or
compressor operated by a separate power source which imposes sonic
waves or an increase of fluid pressure upon fluid contained in said
well bore above said packed off lower portion of said well bore
which is in communication with said fluid containing formation.
38. The method of claim 36 wherein said low pressure void or zone
of rarefaction comprises a substantially instanaeous rarefraction
or cavitational modulation imposed on a sonic wave in said fluid in
said lower packed off portion of said well bore which is in
communication with said fluid containing formation.
39. The method of claim 38 including varying the phase angle of
said rarefaction or cavitational modulation in relation to said
sonic wave, producing recognizable variations in said seismic
energy recorded at said surface or at said well bore.
Description
BACKGROUND OF THE INVENTION
Broadly this invention discloses methods of use of created low
pressure voids or zones of rarefaction within well bores at
locations adjacent to fluid containing subsurface formations and
wherein these created voids within the well bores causes a rarefied
surge of fluids and other matter from the subsurface formations
into the created voids within the well bores.
These low pressure voids impressed upon the fluids of the
subsurface formations, which may be oil, gas, water or other types
or mixtures of fluids, may become sources of seismic energy for
delineation of various types of subsurface fluids or formation
structures existing adjacent to or in the area surrounding the well
bores in which the voids are created.
For the sake of clarification of the hereinafter disclosures
relating to this invention, the creation of the low pressure voids
or the zones of rarefaction and the substantially instantaneous
primary negative pulse or surge of fluid thereinto is termed an
implosion and the positive pulse or reactive surge of fluid outward
therefrom is termed an implosive reaction.
An implosive effect, as distinguished from an explosive effect, is
generally created by the primary immediate inrush of a high
pressure fluid into a created zone of low pressure.
This invention relates to methods and apparatus for creating
implosions and implosive reactions. More particularly, this
invention relates to apparatus for creating implosions and
implosive reactions within a relatively confined space having
fluids under pressure. Still more particularly, this invention
relates to apparatus and methods useful in treating subsurface
formations.
This invention also relates to the use of implosions and implosive
reactions as an augmenting or modulating method and means for sonic
waves which are from a source either in the form of single pulses
in any timed or irregular fashion or with periodic pulses being
created or maintained in fluids.
This invention also is inclusive of method and means of
transference of sonic or energy carrying waves across boundaries of
various pressures and types of fluids within confined areas of
fluids and particularly so in the treatment of subsurface
formations. The problem of creating an implosive reaction resides
first is establishing a zone or space of low pressure within the
confines of a high pressure fluid. In some instances the high
pressure is caused by hydrostatic pressures or in other instances
by mechanically created pressure such as with pumps, compressors,
etc. Secondly, the problem is one of establishing instantaneous
communication or collapse between the low pressure space and high
pressure fluids. The enormity of the implosive reaction and its
resultant pulses will vary according to the differential pressure
established between the low and high pressure spaces, the volume of
the low pressure space, and upon the instantaneous communication
between the two spaces.
Typically, the implosive reaction caused by the instantaneous
communication of high pressure and low pressure zones creates an
initial negative or rarefaction wave impulse instead of a positive
pulse as is created from an explosive reaction. Immediately
following the rarefaction wave pulse is the opposite reactive,
compression or positive high pressure pulse. In some instances this
latter pulse energy is greater than the former. As used and defined
herein the term implosive or implosion reaction pulses is defined
to include both the initial rarefaction pulse and positive or
compression pulse and those pulses resulting thereafter.
The above information relative to implosions and implosive
reactions was substantiated by instrumentation and results by the
use of the apparatus shown in detail in my earlier filed
applications parent hereto, wherein the so-called cavitation valve,
detailed in originally filed FIGURES therein herebefore is
controllably operated as to timed periods of operation in the
creating of and/or modulating of sonic waves. It was found that a
substantially instantaneous collapse of high pressured fluid into a
created low pressure zone within the confines of the high pressured
fluid could be achieved by proper operating control of this
so-called cavitation valve, and that the substantially
instantaneous collapse of the high pressure into the void caused an
implosive effect that was followed thereafter with a very severe
impactual shock wave or an implosive reaction pulse. It was the
results of these findings and the knowledge that this cavitation or
implosive wave generator could be placed down within the well bore,
next to the productive formation if desired, that resulted in the
filing of my parental application Ser. No. 853,405 on Nov. 16,
1959, now U.S. Pat. No. 3,255,820.
In the art of drilling and producing subsurface formations
containing typically oil, gas or water, or combinations of these,
it becomes necessary from time to time to workover and/or
completely clean out the well formation to more efficient
production therefrom. Well known completion techniques such as
hydraulic fracturing, acidizing and perforating have heretofore
been taught and used by others. However, these completion and
workover methods and apparatus typically involve the use of what
might be broadly termed an explosive or positive pressure
characteristic for their usefulness. In some instances it has been
found that this prevents the immediate removal of debris, mud-cake,
sand and the like from the plugged pores of the subsurface
formation and usually tends to wedge them deeper into the
formation.
In the normal production or swabbing of fluids from subsurface
formations by the continuous withdrawal of a packer it appears that
the low pressure area produced below the pump or swab brings
debris, sand or cement materials into narrowed portions of the well
causing plugged or decreased fluid permeability.
In some instances where a swab operation has been used alone in
wells increased production has occurred by the mixing of higher
molecular weight hydrocarbons into the lighter produced crude
aiding flow through previously blocked channels or pores. In other
instances, however, the swabbing disturbs these heavier ends
without solvent or blending action with the lighter ends, forcing
them to the well and decreasing permeability.
In many wells the gas produced around the subsurface formation will
come out of solution with the oil causing a reduction in
temperature of the produced fluids which in turn causes the heavy
end hydrocarbons of the produced fluids to deposit or settle out
within the immediate area of the formation causing plugging and
reduced permeability.
Accordingly, it becomes an important feature of this invention to
provide methods and apparatus for use of implosive reactions which
overcome the objections to methods and apparatus heretofore taught
and used.
In the methods and apparatus disclosed in my parental application
Ser. No. 665,995, filed June 17, 1957, now U.S. Pat. No. 3,302,720,
it was found that this heretofore noted cavitation or implosion
valve worked very satisfactorily at the surface in its initiating
of cavitational or implosive reactions and in its augmentation or
modulation of other sonic or energy carrying waves. Especially was
this so where the subsurface formations had sufficient reservoir
pressure or where the permeability was of small enough value so
that the well bore could be pressured up with but small fluid loss
into the interstices of the formation.
However, it was found that many productive formations would not
sustain a column of pressured fluid without pumping in great
amounts of unwanted fluids which will contaminate and lower the
productive capacity of the formation or which will require a good
deal of time for the fluids to be displaced from the interstices of
the formation. Therefore, where it became desirable to controllably
select the intensity or energy of pressure wave output from
implosive reactions and/or modulated sonic waves, as by increasing
the pressure of the fluid in which the pressure waves are being
created, this method and means was provided whereby limited amounts
of fluids are allowed to go into the formation whereby the well
bore at the surface could be controllably pressured, yet permitting
sonic or energy carrying waves created at the surface to have their
energy content transferred into and out of the formation with
substantially no loss except that which is helpful in increasing
production from the formation. Such a method and means is provided
as an object of this invention wherein apparatus as described is
placed at selected locations in well bores, preferably adjacent a
productive formation, and by controllable back pressure (and/or
variance of exposed areas) between that of a high pressure
hydrostatic column of fluid in the well bore and a lower pressure
of fluid existing in the productive formation, a limited amount of
fluid is shoved or injected back into the formation.
Besides the advantages of the method and means of this invention
described above, when used in conjunction with the method and
apparatus detailed and taught in my parental applications Ser. No.
241,647 filed Aug. 13, 1951, now U.S. Pat. No. 2,796,129, Ser. No.
296,038 filed June 27, 1952, now U.S. Pat. No. 2,866,509, and Ser.
No. 665,995 filed June 17, 1957, now U.S. Pat. No. 3,302,720, there
are other advantages and objects such as provision for method and
means to introduce gases, preferably liquefied, into productive
formations without interference to the transfer of sonic or
pressure wave energy in the well bore by the gas becoming
vaporized, as during rarefactions of the sonic waves or of the
inplosions.
OBJECTS OF THE INVENTION
One object of this invention is to provide methods and apparatus
for general industrial or well use of an implosive action or
reaction by the collapse of high pressure fluids under pressure
into a zone or space of low pressure and further to provide means
for regulating said action or reaction by variations in volume
between the two zones (i.e. vary either the high or low pressure
volume), the resulting differential pressure and the speed of
communication between the two zones.
Another important feature and object of this invention is to
provide methods and apparatus for creating implosive reactions and
to provide means for utilizing the resultant energy from such
reactions.
Another object of this invention is to provide a method and
apparatus for treating subsurface formations and fluids for
increased production therefrom by the creation of an implosive
reaction within the producing formations in situ, or within the
well adjacent the formation.
A further object of this invention is to provide methods and
apparatus for increasing production of fluids from subsurface
formations and maintain solid material in suspension during
swabbing or creation of a zone of low pressure below an upward
moving piston device by simultaneously creating one or periodic
implosive reaction pulses of predetermined amplitude and phase
relationship, the motivating force for such reactions caused by the
upward pull of said piston or swab.
Another object inclusive of the above object is to provide methods
and apparatus for causing intense single or periodic pressure peaks
following, equal to or greater than the pressure change of each
negative implosive reaction pulse.
Another object of this invention is to provide implosive wave pulse
forms having predetermined and controllable characteristics for
application to subsurface formations.
Another object of this invention is to provide methods and
apparatus for producing and lifting fluids from subsurface
formations to the surface by implosive reaction pulses created
within the well, said pulses continuing upward for maximum lift
and/or radiated downward in a short periodic manner.
Another object of this invention is to provide apparatus for
creating implosive and resultant impulses which is removably
anchored in a well adjacent a subsurface formation, said impulses
created by pressure fluid movement through the apparatus.
A further object of this invention is to provide methods and
apparatus which is releasable under extensive hydrostatic fluid
pressure within a well and further provide apparatus which is
operable only under predetermined hydrostatic pressure loads to
create implosive reactions.
A still further object of this invention is to provide method and
apparatus for creating and utilizing implosive reactions and
resultant pulses to rupture and fracture subsurface formations. An
additional object of this invention is to provide methods and
apparatus in accordance with the above which simultaneously
maintains emulsification of fracturing liquids and/or suspension of
bridging and propping agents such as sand, etc., by the implosive
reaction pulse or pulses.
A still further object of this invention is to provide methods and
apparatus for creating implosive reaction impulses in combination
with a reciprocating "cable tool" drilling rig which causes said
impulses to not only assist said drilling but also lift fluids from
the well.
A still further object of this invention is to provide apparatus
adaptable to reciprocating type pumping equipment used in producing
wells whereby implosive reaction pulses are created in combination
with said reciprocation.
An additional object in accordance therewith is to provide a
unitary pumping structure for wells which eliminates standing
valves at the lower end of the production tubing and for creating
kinetic energy from an implosive reaction to assist in pumping
fluids from the formation. Additional methods and apparatus include
selective and continuous fracturing of the subsurface producing
formation by the combined pump and implosive reaction generator. A
further object includes means for preselecting the intensity of the
resultant implosive reaction prior to insertion within a well which
is based on predetermined hydrostatic or mechanical pressure.
A yet further object of this invention is to provide apparatus
which may be readily inserted and withdrawn from a well with
appropriate bypass, safety and release mechanisms to prevent
sticking and overloading by fluid columns in the well.
A still further object of this invention is to provide apparatus
and method for creating implosive and resultant reactions of a
desired pulse form and to further provide means for changing said
pulse form as to intensity and frequency readily and simply by an
operator at the surface such as by placement of the apparatus at
preselected distances from the formation or device treated.
An even further object of this invention is to provide apparatus
and method of creating implosive and resultant reaction pulses
useful in secondary and tertiary recovery of oil from subsurface
formations.
Still another object of this invention is to provide method and
apparatus for treatment of subsurface formations with implosive and
its resultant reaction pulses while simultaneously or in
combination with well known well workover and completion techniques
such as hydraulic fracturing, acidizing, perforating, and
cementing, etc.
A further object in accordance therewith is to provide methods and
apparatus for injection of treating fluids such as fracturing
fluids, solvents, acids, etc., simultaneous with the aforesaid
implosive reaction pulse or timed for introduction at predetermined
phase angle of the initial pulse or resultant pulses.
Another object of this invention is to provide methods and
apparatus for creating implosive reactions wherein the causative
force for actuation of said apparatus occurs by fluid velocity or
quantity of flow or pressure or by separate and distinct sonic wave
generators.
Yet another very important object is to provide method and
apparatus whereby sonic wave generators at the surface may have
their sonic wave output, whether in the form of single pulses in
any timed or irregular fashion or in the form of periodic sonic
pulses capable of creating and maintaining sonic standing waves in
the well bore and/or into the formation, augmented or modulated
adjacent the formation for controllable effects upon, into and
through productive formations.
Another important object in connection with the last above object
is to use the means adjacent the formation as a controllable method
and apparatus for allowing but limited entry of pressured fluid
that is in the well bore into the formation while allowing transfer
of sonic wave energy from the surface down the well bore and into
and out of the formation.
A further object is to provide method and means whereby liquefiable
gas may be introduced into and taken from productive formations
without interference to sonic wave energy being transported in well
bores.
Another very important object is to provide method and apparatus
whereby sonic and energy carrying waves may be transformed and
transferred across various pressure boundaries with substantially
no attentuation of wave energy.
A further object is to provide methods and apparatus for producing
implosive reactions simultaneously or in various phase
relationships in two or more wells connecting with the same
subsurface formation during swabbing, producing, treating or
secondary recovery of the fluids from said well or wells.
A still further object of this invention is to provide methods and
apparatus for creating implosive reactions in combination with
subsurface reservoir testing means, said combination being of
unitized construction to include other well known subsurface
formation treating processes, solutions, and apparatus controlled
at the surface in a step by step operation or in automatic timed
sequence. In accordance therewith, it is an even further object of
this invention to provide a unitized apparatus for perforating a
formation or casing, fracturing said formation with an implosive
pulse, treating the formation with treating fluids, testing the
amount of formation reservoir energy and sequentially plugging same
permanently or temporarily, if necessary.
An even further object of this invention is to provide apparatus
useful particularly in wells for creating heat energy by producing
an implosive reaction in or adjacent the well and by the means of
the implosive reaction to transfer sensible heat from the well to a
distance in the formation.
A still further object is to provide apparatus for creating
implosive reaction pulse or pulses capable of operation in wells
from a wire line, tubing, sucker rods, drill pipe and the like.
Another important object is to permit the use of treating fluids in
a producing formation by the use of the implosive reaction wherein
the means of causing the reaction and the treating fluids are
isolated from fluids of the well bore and are lowered into place in
the well bore on a wire line or pump rods. Yet another object in
conjunction with the last above object is to use the pressure of
the fluids within the well bore as an assisting means in causing
the treating fluids to go into the producing formation. A further
object in conjunction with the last two objects is to provide means
so that fluids from the well bore may follow the treating fluids
into the producing formation.
These and other objects will become more apparent upon further
reading of the description, operation and claims of this invention
when taken in conjunction with the following drawings of which:
FIG. 1 is an elevational view partly in section of apparatus
constructed in accordance with this invention as suspended in
operational position within a well on a wire line cable.
FIG. 2 is an additional diagrammatic illustration of the apparatus
of FIG. 1 suspended within the well on a tubular attachment
conduit.
FIG. 3 is a top continuation of the apparatus according to FIG. 4
and represents an enlarged elevational view partially in
cross-section of apparatus for attachment to surface operational
wireline, sucker rods, tubing or other apparatus, not shown.
FIG. 4 is a detailed front elevational view, partially in
cross-section, of an implosive pulse generating apparatus useful in
wells according to this invention.
FIG. 5 is a partial cross-sectional view of additional attachment
apparatus for the apparatus of FIG. 4 useful according to another
embodiment of this invention.
FIG. 6 represents a back-off or safety attachment device to the
apparatus of FIG. 4 which is useful in a further embodiment
according to this invention.
FIGS. 7, 8 and 9 are views of an implosive reaction method and
apparatus constructed according to an embodiment of this
invention.
FIG. 10 is an elevational view, partly in section, of the apparatus
of this invention in combination with well completion or workover
tools in accordance with an additional embodiment and method of
this invention.
FIG. 11 is an upper continuation of the apparatus and methods
described in FIG. 10.
FIG. 12 is a sectional view taken along the line 12--12 of FIG.
4.
FIG. 13 is a front elevational view partially in cross-section of a
wireline operated embodiment for use in various well treating
procedures using the implosive pulse generator according to this
invention.
FIGS. 14 and 15 are cross-sectional views taken along the lines
14--14 and 15--15, respectively, of FIG. 13.
DESCRIPTION
Referring now to FIGS. 1 and 2, the apparatus of this invention is
described in relation to use within a relatively smooth bore well
casing 10. In the view of FIG. 1 connector 12 is for attachment to
well known and used wirelines socket tools 13 or sucker rods (not
shown) for movement, placement and operation of the apparatus of
this invention in casing 10. The attachment 12 is more clearly
illustrated in FIG. 3. For attachment to tubing 11, or hollow
sucker rods, connector 12A is used. This is likewise described in
FIG. 5 in greater detail. Numeral 14 (see FIG. 1) designates one or
more passageways extending from the fluid filled annulus space 15
into tubular passageway 16, shown more clearly in FIG. 3. Wireline
18 extends from socket 13 to a winch or pulling apparatus at the
surface, not shown. Stuffing boxes 20 and 20A are adapted to seal
the annular space 16 between wireline 18 and casing 10. Valved
connection 22 permits fluid control within space 15. Valved
connection 24 (see FIG. 2) permits fluid control to tubing 11. The
implosive reaction pulse generator is generally indicated by
bracket 30 and extends within the well casing 10 to predetermined
positions with respect to a subsurface formation 32 having
perforations 34 providing communication with the well.
Referring now to the combined views of FIGS. 3 and 4, implosive
reaction pulse generator 30 is described in relation to its use and
placement within a well using a wireline or sucker rod, not
shown.
A check valve 40 and seat 42 are adapted to regulate fluid flow
through passageways 14 and 16. Resilient spring means 44 is adapted
to maintain valve 40 in a normal closed position against seat 42
and further regulates the pressure at which valve 40 will be forced
open or away from seat 42. Rotation of threads 46, part of
attachment or connection 12 and valve seat 42 regulates the tension
of spring 44 for control of the operating or opening pressure
necessary to force valve 40 away from seat 42, the full operation
and function of which will be hereinafter described.
Threaded lock nut 48 retains the spring tension position by
movement about threads 46 into engagement with valve housing member
50. Valve 40 is retained in a non-opening position by threaded
movement of adapter 12 to a lowermost position. In one embodiment
valve 40 is forced in sealing abutment with a portion of the valve
housing 50 therebelow by movement of adapter 12. Valve housing 50
threadably interconnects between adapter 12 and the implosive
reaction generator 30 with one or more tubular subs 52 for
attaining a desired length. The sub includes central bore 54 common
throughout the length of the apparatus 30 from valve 40 into
communication with the fluid in the lower portion of the well.
An inner mandrel 56 is threadably coupled to tubular sub 52 or in
some instances directly to valve housing 50 and extends for the
length of implosive pulse generator 30. An outer mandrel 58 is
threadably connected to inner mandrel 56 at its upper end. The
outer mandrel is adapted to receive unidirectional packing 60 such
as the well known "cup type" packers as used in well servicing
techniques and completions. The packer is adapted in one embodiment
to be slidably received about mandrel 58 between an upper stop 62
and a lower stop 64. In the lower position shown, the packer is
sealed to prevent fluid movement in the annular space 15 from above
to below. The bottom portion of the packer, under fluid pressure
above, tends to seal against stop 64. A splined or beveled portion
66 is provided adjacent packer 60 as shown such that when the
packer is moved upward relative to mandrel 58, as occurs during
lowering within the well, fluids will bypass from below to above.
In the event an overloaded condition occurs during upward movement
of the apparatus, or it becomes undesirable to swab the fluids
above packer 60, a shear release mechanism can be incorporated
between the packer and mandrel 58 to permit bypass of fluids.
Bypass can likewise occur by opening of valve 40 permitting fluid
flow across generator 30.
Passageway 67 extends from above bypass splines portion 66 and
packer 60 providing communication from the annulus space 15 into
main cylinder space 68 formed between outer mandrel 58 and inner
tubular mandrel 56. A cylindrical piston 70 is sealed between the
inner and outer mandrels using O-ring type seals 72. The piston
includes a connected sleeve portion 74 adapted for reciprocation
therewith. Movement of the piston and sleeve is regulated as
desired by spring 80 which normally tends to force sleeve 74 and
piston 70 upward. A retaining sleeve 82 about mandrel 56 is engaged
with retaining nut 84 threaded along the inner mandrel at the lower
end to adjust tension of spring 80. Threaded lock nut 86 is
provided for maintaining such a setting.
Slidably received about piston sleeve 74 between it and the outer
mandrel portion 58 is assembly sleeve 88 which, as seen in
cross-section, comprises an upper sleeve portion 90 sealed with
respect to the sleeve 74 by O-ring packing means 92. A splined or
slotted portion 94 exists longitudinally of assembly 88 to permit
bypass of fluids in the annular space across unidirectional packer
96. Packer 96 extends in an operational direction opposite that of
upper packer 60. This packer is in all respects similar to the
packer 60 in its unidirectional operation and design, i.e., allows
movement of fluids in one direction and prevents flow in the other
direction when so positioned during operation. The cylindrical
assembly 88 is normally in the position as shown permitting bypass
of fluids within the annulus space across packer 96 through slots
94 by the tension of resilient spring means 98 acting between lower
sleeve 100 and retaining nut 102 which is threaded about inner
mandrel 56 and held by lock nut 104. One or more spring loaded
latching devices 106, one of which is shown in cross-section, is
provided about the periphery of assembly 88 to cause engagement
with sleeve 74. Latch 106 is movable about a shaft 108 maintained
by spring means 110 abutting against cylindrical assembly 88, in
engagement through a lip 112 into a recessed portion 114 of piston
sleeve 74, the operational movement of which will be hereinafter
described.
Latch member 106 is adapted, upon rotation about shaft 108 against
the tension spring 110, to be disengaged from recess 114 by
striking release cylinder 116 which is threadably adjusted to a
sleeve 118 formed as a part of nut 84. A lock nut 120 prevents
movement of the cylinder 116. The lower outside threaded portion of
the inner mandrel 56 is adaptable to be attached with other well
servicing and drilling equipment, such as perforators, well pumps,
etc.
Referring now to the embodiments described in FIG. 5, the apparatus
is similar to that described in FIG. 3 in that it describes a top
continuation attachment for the implosive reaction pulse generator
mechanism 30.
The device has primary utility for attachment to tubing, drill
pipe, hollow sucker rods and the like using adapter 12A forming
passageway 16A. The passageway terminates with a rupture seal disc
130 formed as a part of valve 40A. The "go-devil" device 132
illustrated is designed for operation with the device of FIG. 5 to
rupture disc 130 and includes a body portion 134 and guide vanes
136.
Referring now to the safety back-off device 138 of FIG. 6, the
apparatus is typically installed between implosive pulse generator
30 and the upper attachment valve housing 50. However, in some
instances it is attached above valve housing 50 to adapter 12A. The
device includes upper and lower cylindrical members 140 and 142
attached to each other by left-handed threads 144. Bypass openings
146 are sealed from the annulus space by O-ring seal 148. In the
instance a release of pressure from space 54 becomes necessary, as
for example when removal of generator 30 is desired without
swabbing the well and/or creating implosive pulses, right-handed
rotation of cylinder 140 with respect to fixed cylinder 142
releases the seal 148 and permits fluid communication from annulus
15 to interior space 54 through openings 146.
Cylinder 140 of the safety back-off device 138, in one embodiment,
is rotated sufficiently to allow ports 146 to be opened without
being physically parted. This is dependent upon the length of the
threads 144 with respect to ports 146. In those instances where the
generator and/or parts connected thereto are stuck within the well,
member 140 may be physically separated to permit appropriate
fishing tools to connect with member 142 and remove the stuck
apparatus from the well. The relative rotation in either of the
above instances occurs by reason of the anchored generator which is
held by pressure or stuck within the well.
FIGS. 7, 8 and 9 are views of an implosive reaction method and
apparatus constructed according to an embodiment of this invention.
The arrows are indicative of the motion of parts and pressure
fluids.
FIGS. 10 and 11 show an assembly of an alternate embodiment using a
bullet or shaped charge perforating device 150 attached at the
lower end of implosive pulse generator 30. Tubing 11 connects with
tubing 52 above generator 30 through connector 12A, valve housing
50 and safety back-off 138, as described in FIGS. 5 and 6. Tubing
11 terminates at the surface with cap 152. Conduit 24 interconnects
tubing 11 with various well treating materials schematically shown
in containers 154 and 156 and 158, such as acids, fracturing
fluids, solvents, plugging materials such as cement, etc., which
are appropriately connected with a pump means 160. Block diagram
162 represents an energy source such as a pump, compressor, or
sonic wave generator such as tose disclosed in my parental
application Ser. No. 665,995 filed June 17, 1957, now U.S. Pat. No.
3,302,720, which connect with annulus space 15 to provide energy as
may be desired to actuate implosive pulse generator 30, as
hereinafter described.
Referring now to FIGS. 13, 14 and 15, apparatus is illustrated for
operation in connection with the implosive reaction generator 30
when supported within a well on a wireline or pump rods and when it
is desired to treat a subsurface formation with increment injection
of fluids such as acids, fracturing fluids, solvents, emulsions,
sealing or cementing agents, etc. Connector or adapter 200, similar
to adapter 12 (in FIGS. 1 and 3) represents the top of the
apparatus for attachment to a wireline socket or pump rod coupling,
not shown. The adapter is threadably attached to barrel 202 at
threads 204. Passageway 206 provides communication between annulus
space 15 and space 208. Barrel 202 terminates at lengths up to
several hundred feet or more for deep well use to a lower connector
210 at threads 212. Lower threads 214 are usually attached to
coupling 12A and valve housing 50 of the device shown in FIG. 5,
safety sub 138 and thence generator 30, respectively, somewhat
similar to the view of FIG. 1.
Barrel 202 is divided into a multiplicity of separate chambers
using one or more piston devices such as 216 and 218. Free piston
216 provides a solid seal separating chamber 208 and chamber 220
using an O-ring seal 222. Free piston device 218 comprises a type
of check valve permitting bypass of fluids within chamber 220 to
lower chamber 224, optional heating chamber 226 and thence space
227 above valve housing 50. The valved piston 218 includes a solid
valve seat 228 threaded at the lower end 230 for sleeve 232 which
holds perforated retaining ring 234 and spring 236 acting against
piston 238 sealed against valve seat 228 and against barrel 202
with O-ring seal 240. One or more ports 242 are located about the
interior of piston 238, the functional use of which will be
hereinafter described.
Chamber 224 terminates with a control orifice 244 which is seen in
the cross-section of FIG. 14. The orifice includes a central
opening 246 terminating the beveled stop surface 248. At least one
opening 250, preferably more, are spaced about the outer portion of
orifice 244 and are of such diameter that they intersect with the
beveled surface 248. Orifice 246 and openings 250 provide
communication with optional heating chamber 226 from chamber
224.
Heating chamber 226 includes a resistor type heating coil 252 such
as sold under the trademark "CALROD" which is connected to
insulated electrical connection 254 adaptable for connection and
operation with conductor cable 18, not shown in this view. The
electrical connector 254 is attached or clamped to barrel 202 is a
manner well known to those skilled in the art.
OPERATION OF IMPLOSIVE PULSE GENERATOR AND/OR SONIC WAVE
MODULATOR
Although there are numerous methods and processes adaptable to this
invention, broadly speaking, such as in industrial usage, the
purpose of the apparatus described heretofore is the creation and
usage of an implosive pulse and resultant pulses within high
pressure fluids which is specifically adaptable to all phases of
oil well seismic exploration, drilling, completion, workover and
production or as an augmenting or modulating means to sonic or
energy carrying waves used in various methods or processes
thereto.
The implosive operation comprises two or more fundamental steps:
(1) the creation of at least two separate fluid volumes having
differential pressure therebetween, and (2) the instantaneous
collapse or communication between such volumes and a resultant
following high pressure pulse, and (3) if actuated by sonic or
energy carrying pulse or waves steps (1) and (2) become a
modulating means and method for the particular phase angle to which
they are applied to the sonic pulse or waves and/or an intensifier
of said sonic pulse or waves.
Referring specifically now to the apparatus illustrated in FIGS. 1,
3 and 4 and FIGS. 7, 8 and 9 which are a preferred mode of carrying
out the invention, the numerals used in FIGS. 7, 8 and 9 refer to
like numerals in the specific apparatus of FIGS. 3 and 4. Packer 60
is described, however, as a fixed packer for the purpose of
simplification. Preferably the apparatus 30 is used in conjunction
with a confined bore such as a cased well 10 filled with a fluid
supplied through conduit 22 or filled with produced fluid from
formation 32.
However, the use of apparatus 30, or other means that will perform
like methods of operation, is not confined to use in well bores but
may be used generally in industrial methods and processes as well
as those uses later described in this application wherein the
following detailed description and mode of operation is applicable
and wherein casing 10 may be any confining medium or means wherein
the methods and processes herein may be performed.
Using connections 12 and 13, valve housing 50 and tubular subs 52,
implosive pulse generator 30 is lowered on wireline 18 to a desired
position within the well with respect to formation 32. Well fluids
are permitted to bypass packers 60 and 96 through splined areas 66
and 94 respectively during the lowering operation. The initial
starting position will depend to a great extent upon the treatment
desired. For example, it has been found that by locating lower
packer 96 at distances from formation 32 equal to multiples of
one-quarter of the wave length as predetermined or desired from
generator 30 this causes reinforcement of reflected pulses from
formation 32 when repetitive or periodic pulses are generated.
Reinforcement of the compressive wave pulse following the rarefied
implosion reaction pulse occurs through proper placement of valve
40 with respect to the end of mandrel 54 permitting fluid injection
during the compression part of the pulse or wave. Even further
reinforced energy of the compression wave occurs by injecting
heated fluids, such as gases, solvents, light crudes or driving
fluids such as water and liquefied petroleum gases. This added
energy upon attenuation will drop the energy into reconversion of
heat within the formation.
Under certain conditions such as when desired to prevent
contamination of well fluids existing above generator 30, valve 40
in housing 50 is adjusted to an inoperative position by movement of
connector 12 heretofore described. Using proper length of subs 52
the distance valve 40 extending from the lower end of generator 30
becomes of critical importance in certain operations as hereinafter
described.
In the initial starting procedure the pressure across packers 60
and 96 is in equilibrium. Upon the reversal of movement of wire
line 18, e.g., upward, bypass slots 66 are closed as packer 60
seals along mandrel 58 and shoulder 64. Accordingly, fluid within
the well space 15 is prevented from passing from above to below the
packer 60, by fluid pressure expanding same into sealing engagement
with tubular casing 10. Further upward movement of mandrels 56 and
58 force pressure fluid such as hydrostatic pressure fluid into
bypass 67 and cylinder space 68, forcing piston means 70 and its
attached sleeve 74 downward. The amount of pressure necessary to
force movement of piston 70 under the action of high pressure
fluids is largely determined by the size, type and predetermined
tension setting of spring members 80 and 98. Due to interlocking
engagement of latch 106 by lip 112 in recessed portion 114, the
cylindrical assembly 88 is likewise caused to move downward with
the sleeve and piston. Spring 110 associated with latch 106 and
assembly 88 maintains this interlocked relationship. Further
movement of piston 70 and assembly 88 under the pressure existing
in cylinder 68 forces the upper portion 90 of assembly 88 into
sealing engagement with the lower packing means 96 thereby shutting
off packer bypass channel 94. Further movement thereof causes
increased pressure to occur on the lower side of packing element 96
forcing it into sealing engagement with casing 10 similar to that
described with packing element 60. Continued movement and
withdrawal of mandrels 56 and 58 upward begins the creation of a
low pressure space between the two packing members 60 and 96 by the
relative movement of the mandrel members and packer 60 upward with
respect to downward movement of packer 96 in an opposite direction.
This zone of low pressure is sealed from the fluids within the
casing. It appears that the resultant force of the implosion is
largely a function of the differential pressure across packer 96
and the volume of space between packers 60 and 96. Accordingly, it
is possible to arrive at a predetermined intensity of implosive
effect by control of operational movement between the packers 60
and 96 and control of the amount of pressure existing about the low
pressure zone created. Assembly 88 continues movement downward
until latch means 106 strikes release or tripping member 116,
providing an instantaneous movement under the action of spring 98
against lower sleeve 100 of assembly 88. Since release member 116
is threadably adjusted upon retaining sleeve 118 the distance and
length of movement and hence resultant implosive effect may be
readily adjusted or pre-set. The total movement of packers 60 and
96 relative to each other depends upon many characteristics and
conditions in addition to the type of workover or completion
techniques required. This relative movement may be a matter of a
fraction of an inch up to several inches or more.
Although there is some discrepancy as to actually where the
implosive reaction pulse is created, it appears that upon the
substantially instantaneous release of assembly 88 packer 96
likewise moves into abutment with mandrel 58. This instantaneous
packer movement away from the pressure fluid below creates a low
pressure void into which the high pressure fluids below instantly
communicate to cause the initial rarefaction wave pulse. In other
instances, due to changes in spring tension and inertia between
assembly 88 and packer 96, there is instantaneous communication in
space 94 between the low pressure space between the packers and the
relatively high pressure fluid space outside. It is known that an
"in-rush" of fluids establishes the implosive reaction.
Repeated or periodic implosive pulses occur by lowering generator
30 permitting spring tension 80 to return sleeve 74 and piston 70
into engagement with latch 106. Another method consists of
alternately releasing the pressure within cylinder 68. A yet
further method is the use of a sonic pulse or periodic sonic wave
being caused in the fluid within space 15 of casing 10, as for
example using the various methods and apparatus referred to in
parental application Ser. No. 665,995, filed June 17, 1957, now
U.S. Pat. No. 3,302,720, which is a continuation-in-part of prior
applications Ser. No. 241,647, filed Aug. 13, 1951, now U.S. Pat.
No. 2,796,129, and Ser. No. 296,038, filed June 27, 1952, now U.S.
Pat. No. 2,866,509. As taught therein these sonic pulses are either
single pulses in any timed or irregular fashion or periodic pulses
capable of creating and maintaining in the fluid above the
implosive pulse generator 30 a sonic standing wave of multiples of
a quarter wavelength of the fundamental frequency or one of its
various harmonics. In many instances the created implosive and
associated pulses release the pressure sufficiently to cause
re-engagement with assembly 88.
The generator unit 30 may be activated by periodic upward movement
and return of the unit to the original position or by allowing the
generator unit 30 to remain in a fixed position from the formation
and the bottom of the well in combination with the activation means
described in the previous paragraph, that is, by a sonic pulse or
by momentarily increasing the pressure of the fluid above the
generator 30 or by pressure fluid flowing past and through the unit
30.
In operating the generator unit 30, typically the operator selects
the placement at a distance of a quarter wave length that was less
than the quarter of a wave length of the fundamental frequency of a
sonic wave in the medium being used and hence causes the generator
unit to operate at one of the many quarter waves of the harmonics
of the fundamental frequency and thus maintain a standing wave
condition of sonic waves below unit 30. If the unit is pulled
upward continuously, as in a swabbing operation, then the reflected
standing wave from the generator unit would be of an increase in
wave length going through the various harmonics of the fundamental
frequency of wave length in the particular fluid contained in the
well. Accordingly, valve 40 would open due to the rarefaction
portion of the pulse. The length of the tubing upward actually
regulates in time the arrival of the fluid and its joining the
fluid below the valve at a phase angle with the pulses from
generator unit 30 and the particular quarter wave length of
harmonics selected and the resultant position of unit 30 from the
bottom of the well. This regulates the distance valve 40 will be
above generator unit 30 in order to have the fluid combine with the
standing wave impulses at the desired phase angle portion of the
standing waves.
Operation in accordance with this invention using tubular apparatus
of FIGS. 2, 5 and 6 is substantially the same as using the wireline
apparatus described above, i.e., the implosive generator 30
operates in the same manner. The tubular apparatus has particular
utility when it is desired to continuously add treating fluids or
materials to the subsurface formation below the generator 30
independent of annulus fluids, as more particularly described
heretofore and generally under the sub-heading WELL COMPLETION
hereafter.
The implosive reaction occurring from the communication of high and
low pressure zones in the fluid about packing members 60 and 96
causes a negative or rarefaction pressure pulse. This pulse is
impressed upon the pores of the producing formation through the
coupled fluid existing within the well and formation. The fluid
exists within the well as produced fluids or is pumped into the
well prior to inserting of generator 30. Accordingly the coupling
fluid used is an important phase of this invention in well
completion and workover. If the apparatus is used primarily as a
swabbing tool, the formation fluids will form the coupling medium
whereas in other instances oil well acids, solvents, fracturing
fluids and drilling fluids are also capable of use with the
invention. Following the negative pulse there will be a positive
pressure pulse of up to several thousand atmospheres per square
inch or higher. Likewise, the high pressure pulse immediately
following the rarefaction pulse enters the producing formation with
increased beneficial effect for increasing production of fluids
therefrom but unlike the rarefied pulse is also propagated upward
within the well.
SWABBING WELLS
The apparatus is readily adaptable for use as a type of wire line
swab for cleaning oil well formations as illustrated in FIG. 1. By
a continuous withdrawal of the device up the well an alternating
implosive reaction occurs during such travel until the hydrostatic
fluid pressure in space 15 is incapable of further movement of
piston 70 within the generator.
Where the device is continuously withdrawn up the well valve 40
must be set in an operating condition whereby the upward pull of
the device is not sufficient to cause opening of the valve. The
valve is caused to be opened, however, when the rarefied wave pulse
travels upward in tube space 54 and reaches the underside of valve
40. The differential pressure across valve 40 causes the valve to
open, allowing fluid thereabove to be induced down tube 54. This
same induction of fluid at valve 40 also causes piston 70 and
member 74 to move upwardly by the action of spring 80 relatching
into assembly 88 which carries lower packing member 96. In this
manner fluid above generator 30 is caused to go into the fluid
existing below during the compressive or high pressure pulse that
follows the rarefied pulse due to the implosive reaction.
As the generator is pulled along the well the implosive reaction
pulse begins to vary in frequency, such frequency and energy being
sufficient in many instances to fracture the subsurface
formation.
In some instances sufficient pressure is established in the fluid
above the apparatus from auxiliary sources through conduit 22 to
actuate the apparatus where hydrostatic pressure is not available
or is insufficient. A unidirectional (check type) valve can be
located within outlet conduit 22 operable under predetermined
pressure conditions in order to maintain sufficient back pressure
within well space 15 and cylinder 68 of generator 30 for operation.
The implosive rarefaction pulse effect caused by the apparatus
according to this invention places a momentary pressure
differential between the well fluids and the fluids in the
formation with the formation fluids tending to move towards the
well. Thereafter, the rarefaction pulse effect is reversed by a
high pressure impulse into the widened area of the formation near
the well.
In another embodiment instead of a continuous lift swab an
oscillating motion is transferred to wire line 18 from, for
example, a cable tool drilling rig.
It can thus be seen that during what would be a normal swabbing of
a well an implosive reaction occurs by proper setting of device 30
to the amount desired to formation 32.
PUMPING WELLS
The apparatus of this invention has further utility when used in
conjunction with a reciprocating type oil well pump. The implosive
rarefaction pulse creates a momentary suction effect on the
formation fluids bringing them into the pump proper for lifting to
the surface. In addition, the high pressure positive pulse
following causes debris, normally plugging the formation pores, to
be forcefully radiated outward. The reciprocating movement of pump
rods provides the necessary force to actuate generator 30 and to
create the low pressure space with respect to the surrounding high
pressure zones with further communication between them resulting in
the implosive effect. This continued effect not only prevents
clogging of the formation pores and fractures but is also sequence
timed to assist fluid movement to the well surface. In one
embodiment the implosive reaction pulse occurs during the upward
pump stroke, however, this is not to be held limiting as the pulse
can be initiated in the down stroke or on both strokes.
In reservoirs having substantial interstitial fluid pressures, the
apparatus shown in FIGS. 3 and 4 may have its position inverted and
be placed at a selected position in the well bore adjacent the
productive formation. When used in this manner, implosion wave
generator 30 may be caused to operate in a periodic manner from the
sustained pressure of the reservoir fluids. Regulation of the
pumping of this formation pressure induced implosive reaction
operated pumping means may be controlled at the surface as desired
by the amount of fluid allowed to escape from the well head.
By proper location of this formation pressure operated implosive
reaction pump from the bottom of the well bore as compared to the
casing or tubing to the well head at the surface so that even
multiples of a quarter of a wave length or one of its harmonics may
be allowed between wave generator 30 and the bottom of the well
bore and to the top of the well bore, then standing wave conditions
may be set up in the well bore that will assist the pressure energy
of the formation in pumping fluids therefrom, as well as in
assisting in the continuing operation of device 30.
It is also possible to operate device 30 in the upright manner
shown in FIGS. 3 and 4 as a pump actuated by sonic pulses or waves
of any of the various types disclosed in my parental application
Ser. No. 655,995, filed June 17, 1957, now U.S. Pat. No. 3,302,720,
by placing apparatus 30 at a desired location in the well bore
adjacent the productive formation wherein device 30 would be an
assist in maintaining sonic wave energy in the well bore for
pumping fluids from the formation.
WELL COMPLETION
A typical completion or workover of subsurface formations using the
implosive pulse generator of this invention is illustrated in FIGS.
10 and 11. Bullet or jet perforator 150 is fired from the surface
or by timed sequence apparatus to provide openings 34 through
casing 10 into formation 32. Communication exists thereafter, for
example, from the formation to central bore 54 of mandrel 56
through the perforator 150.
Fracturing of the formation, if necessary or possible, occurs in
many ways. For example, valve 40A is placed in an inoperative
position by placing sufficient tesion on spring 44, shown in FIGS.
3 and 5, so that the valve will not open at low fluid pressures
above this valve 40A. Generator 30 is actuated by pressure pulses
in annulus fluid 15 from source 162 or which may be hydrostatic
pressure. The implosive pulse plus the high pressure positive pulse
reaches proportions sufficient to cause breakdown or rupture of the
formation. In some instances incidental fracturing of the formation
from the well bore occurs by the implosion effect. However, it is
preferred to establish pressures in the space below generator 30 up
to or near the formation breakdown pressure prior to initiating the
implosive reaction pulse. Pressures sufficiently greater than the
formation breakdown pressure are created to overcome the overburden
pressure which is generally estimated as approximately equal in
p.s.i. to the depth of the formation in feet.
As a further example of a fracturing procedure, valve 40A in
housing 50 is adapted to open at a predetermined pressure. The
setting of that pressure occurs through adjustment of coupling 12A
being rotated with respect to threads 46 as described in FIGS. 3
and 5. In the preferred embodiment the valve is regulated and
pre-set to open when the implosive rarefaction pulse is initiated
in the coupling or fracturing fluid existing below packer 96 and in
tubular bore 54. As the rarefaction pulse passes the lowermost
portion of the mandrel an induced rarefaction wave is caused upward
through the central bore creating a pressure differential across
valve member 40A, opening same and inducing a pulse of pressure
fracturing liquid from storage 154. The injection of such fluid in
one embodiment is timed with the wave pulse directed toward the
formation being treated to perform cancellation, reinforcement or
augmentation of the induced wave pulses. The additional fluid or
treating liquid in the wave pulse becomes useful as a makeup for
fluids forced into the pores or fractures of the formation.
An even further procedure for rupturing or fracturing subsurface
formations using apparatus of this invention includes use of
rupture seal 130 and valve 40A as illustrated in FIG. 5. When it is
desired to use large quantities of fracturing fluid after
initiation of the fracture using implosive pulse generator 30, seal
disc 130 is ruptured by pressure or go-devil 132. Pump or pumps 160
thereafter force additional fracturing fluid from storage 154 into
the well to expand the fracture with or without simultaneous
implosive pulses.
Although fracturing fluids have been particularly described above,
this is not limiting as other well treating fluids such as acids,
solvents, etc., stored in container 156 may also be used in the
completion or workover of wells in conjunction with the implosive
pulse generator 30.
As a further example of use of the apparatus particularly described
in FIGS. 10 and 11, after perforating and fracturing, a drill stem
test of reservoir 32 can occur by rupture of seal disc 130 of valve
40A permitting fluids to enter tubing 11 for measurement. In the
event productivity is insufficient for producing the formation, or
water encountered, a still further embodiment includes pumping or
squeezing of sealing materials such as cement into the formation
using a pump 160 and sealing materials from storage, e.g., 158, in
a manner well known to those skilled in the art. In some uses no
more pressure is necessary than the hydrostatic head of cement
within tubing 11 to effect operation.
Accordingly, it can be appreciated that this invention concerns
apparatus which is capable of a multiplicity of separate well
treating or completing operations assisted by implosive reaction
pulses and the resultant energy therefrom. Typically, operation of
generator 30 requires a separate power source 162 connected to the
annular space and cylinder space 63. As heretofore explained, this
may be a sonic generator, pump or compressor. In that instance
where generator 162 is a sonic generator and is adapted to maintain
a sonic standing wave to cause actuation of implosive pulse
generator 30, it would be preferable to place the implosive pulse
generator at a predetermined distance from the formation to be
treated so that the distance therebetween can be acoustically
coupled to a multiple of a quarter wave length of the sonic
standing wave being created and/or maintained in the fluid above
the implosive pulse generator 30 thereby causing reinforcement and
augmentation of the implosion and their resultant reaction within
the formation or at the face thereof by reflection.
The sonic generator 162 may impose on the produced sonic standing
wave various modulations whereby the characteristics of the sonic
standing wave actuating the implosive generator 30 may be extremely
variable as to individual waves out of several composing the sonic
standing waves. These periodic sonic waves actuating the implosive
pulse generator 30 may be extremely variable as to individual waves
in that they may have either variations of time and extent of the
rarefaction or low pressure portion, or abruptness and shortness of
time interval wherein vast pressure peaks may be imposed on the
pressure portion, or at various phase angles of individual waves
composing the periodic actuating sonic wave. Accordingly, implosive
pulse generator 30 may have a predetermined setting given to its
tripping means or member 116 in order that groups of the sonic
waves from generator 162 that are substantially uniform or
sinusoidal portion as to its rarefaction and compression portions
thereof will cause the implosion device to be ineffective in
operation and thus to serve merely as a transferring or transducing
means for imposing sonic standing waves into the face of and within
the interstices of the formation. When the modulations are imposed
by the sonic generator 162 upon the periodic sonic standing wave
actuating the implosive pulse generator 30, so that waves of large
magnitude of non-uniformity or non-symmetry of rarefaction and
compression portions occur as previously taught, then the implosive
pulse generator will actuate to produce periodic implosion
reactions on the sonic standing wave resonating at the face of and
within the formation. Accordingly, the modulations produced by
sonic generator 162 will be greatly enhanced, augmented, and
amplified in being transferred through the implosive pulse
generator 30. It is understood that the use of periodic sonic waves
to actuate and enhance implosive pulse reactions as taught herein
and in the above application and patents is applicable to the
various methods taught in this application for uses of implosions
including formation fracturing, fluid injection and producing
methods as well as providing the pumping means for reservoir fluids
of low vapor pressure with the lifting force being the type of
modulations used on the pressure fluids maintained between the
implosive pulse generator 30 and sonic generator 162.
When the various methods and means of my prior parental application
Ser. No. 665,995 filed June 17, 1957, now U.S. Pat. No. 3,302,720,
are used as the sonic generator 162 to operate bottom hole device
30, among several advantages as to the many uses listed in this
application as to the combined use are the following:
It has been found during many years of use of various sonic wave
methods and processes of treating subsurface formations that many
productive formations have not sufficient interstitial fluid
pressure and/or tightness of low enough permeability of the
formation to sustain enough fluid pressure back onto a sonic wave
generator operating at the surface so that enough intensity of
sonic wave may be generated, unless relatively great amounts of
fluids must be introduced through the sonic wave generator and into
the well bore so that a highly pressured acoustic coupling may be
maintained between the sonic wave generator and the formation.
Various pumping means have been attempted to be used in conjunction
with the sonic wave generators in order to sustain high pressures
upon the well heads, but it has been found that where the fluids
were introduced apart from the sonic wave generator, the sonic
waves had disruptive effects upon the pumping means and the pumping
means often interfered with the desired output of the type of sonic
wave from the sonic wave generator to the formation. In order to
correct this, the fluids were introduced into the sonic wave at its
point of generation in the sonic wave generator. Although this was
extremely successful in operation in many formation treating
methods and processes, the many variabilities of formations, even
those in the same field or formation, varied the amount of fluid
that was required to be pumped into the well bore in order to
maintain a pressured fluid upon the sonic generator for it to
generate the desired sonic wave intensity. This varying of the
amount of fluid being introduced into the sonic wave at its moment
of generation caused, where a piston type oscillator was the sonic
wave generating means, an effective increase of lengthening of the
stroke of the oscillator with an increase of input of fluid into
the generated sonic wave. In order to be able to treat the extreme
variability of formations found from well to well and from field to
field, it was necessary to have the sonic wave generator variably
controllable as to its length of stroke, the accelerations
available during said stroke, the control of amounts and pressures
of inputing fluids into and through the sonic wave oscillator, and
means to balance out the vibrations and pressures imposed upon the
system by the sonic wave oscillators, among other things.
By use of device 30 in conjunction with my above described sonic
wave generators, the control of the amounts of fluids desired to be
introduced into a productive reservoir or formation can be
selectively set prior to its introduction into a well bore by the
adjustment of the compression of spring member 44 against valve
means 40 or 40A as shown in FIGS. 3 and 5. By this means, device 30
may be moved from well to well in a particular field and a
formation of substantially the same depth may be treated with about
the same volume of fluid being introduced into each of the wells
during a treatment of the same time period by a presetting of the
opening pressure of valve means 40 or 40A. Thus, considerable of
the variability of controls required in the operation of sonic wave
generator 162 may be eliminated and device 30 may be a transference
as well as a modulating and intensifying means for the various
forms of sonic or energy carrying wave or waves from sonic wave
generator 162.
In various treating and secondary recovery methods and processes
wherein fluids in liquid form are imposed upon the deeper
formations through well bores which often may be several miles in
depth there is relatively enormous potential energy in the well
bore adjacent the productive formation that may be effectively
utilized by the combined use of the device 30 of this application
and the methods and processes of my parental application Ser. No.
665,995 filed June 17, 1957, now U.S. Pat. No. 3,302,720.
This potential energy may be utilized by alternately applying or
transforming its pressure force into an alternate implosive
rarefaction and resultant reactive pressure shock wave which may
be, if desired, combined with various forms of sonic pulses or
periodic waves by varying as desired the effective area of piston
means 70 relative to that of the effective area of piston means or
member 96, and the proper compression settings of spring
compression means 80 and 98 as of FIG. 4 and applying to device 30
the controlling sonic pulse or waves from sonic generator 162 at
the surface or well head. By proper matching of areas of piston
means 70 and 96 relatively low pressures of formation fluids may be
matched to high bottom hole pressures through device 30 and an
acoustic coupling maintained therethrough so that a relatively high
pressured small area of intense sonic wave may be transferred and
transformed across into an effective larger area of sonic wave or
waves that will be capable of allowing the gases contained in the
fluids of the formation to come into and out of solution with the
liquids so that effective treating of formations or driving of
desired recoverable fluids from formations may be accomplished by
being able to localize the sonic energy at the area upon which it
is desired to be effectively used.
In regard to the last above, wherein it has been learned by
considerable field experience that to effectively treat or drive
fluids from formations that it is necessary to have a change of
medium at the face of or in the formation at the areas in which the
sonic wave energy is desired to be utilized. Where liquid is the
acoustic coupling means between the sonic wave generating means and
the formation, it has been found best to use some form of gas as a
receiving or localizing station or means. However, where the gas is
liquefiable or is miscible or absorbable with the liquids of the
formation at the pressures imposed thereon by treating or drive
fluids, then in order to localize or cause reception of the sonic
wave energy at the area desired it is necessary that the sonic wave
energy have rarefactions of sufficient extent as by implosions or
rarefied portions of the wave or waves, so that the gas may come
out of solution and effectively release its work effect whether as
in fracturing of formations or in pulling oil from interstices of
formations. To exceed those pressures wherein gas may remain
liquefied or always in solution allows sonic wave energy to travel
past areas upon which it is desired to localize its energy and
continues out into the formation until the sonic wave energy is
attenuated at various receiving boundaries.
In undersaturated oil and gas containing formations wherein it is
desired to utilize sonic wave energy in the various methods and
processes taught in this application, it has been found that gas,
preferably in a liquefied form, must be introduced to the area
whereupon sonic wave energy is to be utilized. When this has been
done by surface sonic wave generators as depicted by 162 of FIG. 11
of this application or of any of the sonic wave generators of my
prior parental application Ser. No. 665,995, filed June 17, 1957,
now U.S. Pat. No. 3,302,720, it has been found that gas being
released from the formation comes back up the well bore,
particularly so during treating operations such as fracturing, so
that it collects at the well head and, unless it is continuously
bled off, enough gas may accumulate so that interference with sonic
wave transmission to the formation from sonic wave generator may
result.
Also attempting to introduce gas in its liquefiable form or as a
miscible or absorbable agent in the treating of drive fluids at the
surface along with the generation of sonic wave energy causes
considerable problems such as the proper pressures to hold on the
well head relative to the adjusted formation pressure surrounding
the well bore at the bottom of the bore. By the proper use of
bottom hole device 30 along with surface sonic wave generators 162,
gas may be introduced either intermittently or continuously as
desired or dictated by formation conditions and the control of the
amounts of gas and type thereof may be varied at will without
interference with sonic wave transmission and control from the
surface sonic wave generator 162. In such use of device 30 it would
be preferable to replace upper swab cup 60 with a fixed packer to
retain gas therebelow. By referring to FIG. 11 it may be seen that
heat may also be introduced at or adjacent the formation, either in
the form of heated vapors or liquids of various types and these
introduced into the sonic waves during the rarefactions of the
implosions or even of sonic waves transferred and transformed
across device 30 and thus be compressed into the implosive reaction
or the compression portions of the sonic waves going into the
formation.
As a further embodiment of this invention wire line apparatus
constructed according to that illustrated in FIGS. 13 and 14 is of
particular utility in completing wells where smaller quantities of
treating fluids such as acids, emulsions and corrosion inhibitors,
etc., are adequate.
In operation, the treating fluids are placed in chamber 220 above
valved piston 238. This is ordinarily done at the surface with
threaded member 200 and free piston 216 removed from the barrel
202. Barrel 202 is of sufficient length to provide the required
volume of space 220 for treatment of the well; lengths up to
several hundred feet or more for deep wells are taught.
In some instances valve piston 218 is removed, filling barrel 202
including chambers 220 and 226 with treating fluids above valve 40
in housing 50, which ordinarily attaches at lower threads 214.
Usually the back-off safety joint 138 and implosive pulse generator
30 are below housing 50. Valved piston 218 or free piston 216 is
placed on top of the treating fluid for isolation between batches
of other treating fluids or well fluids acting through passage 206
and chamber 208 under hydrostatic pressure head. This latter
pressure assists the entrance of treating fluid at predetermined
phases of implosive reaction, usually the compression pulse through
valve 40 into the producing formation.
If solid free piston 216 is used atop the treating fluids within
chambers 220 and 226, treating fluid entry ceases when the piston
strikes stop orifice 244. In many treating operations, however, it
is necessary to follow one batch of treating fluid with a follower
fluid. In that event valved piston 218 is placed atop the initial
treating fluid with the follower treating fluid thereabove. In some
instances one or more follower fluids are to be injected into the
formation and this would necessitate additional valved piston
members 218. Atop the last of these treating fluids solid free
piston member 216 is used for isolation from the annular fluids. In
operation with valve piston device 218, movement of the treating
fluid into the formation occurs until piston 218 strikes stop
orifice 244 as shown in the dotted line. Further pressure in the
follower treating solution above forces the piston portion 238 from
its seat 228 permitting fluid entry through orifices 242, 250
and/or 246 of the stop orifice. The follower treating fluid batches
continue their injection until solid piston device 216 strikes
valved piston 218. In some instances it is desirable to follow the
treating fluids with fluid from well space 15. This is accomplished
by utilizing valved piston device 218 as the top piston member.
In some well treating operations heating of the treatment fluids
prior to their entrance to the formation is desired. Accordingly, a
heating chamber 226 may be provided as shown attached to the lower
portion of barrel 202. Electrical conduit 254 supplies electricity
to a resistance type heating coil or coils 252 such as that sold
under the trademark CALROD which has an errosive and corrosion
protected and insulated cover. Although it has been found that the
implosive pulse generator 30 in itself creates heat energy which is
capable of being utilized in the formation, the heating chamber 226
adds additional heat energy into a desired phase angle portion of
the compressive pulse resulting from the implosive reaction. This
heating chamber 226 and coils 252 as described above may also be
used above valve 40A where attachment means 12A of FIG. 5 is used
for connecting apparatus 30 to the surface in order to introduce
therein fluids for treating formation 32. In this manner heated
fluids are directly introduced into the compression or high
pressure pulse that follows the rarefied pulse of the implosive
reaction into the formation and upon attenuation of the pulses out
of the formation this heat will be deposited therein for beneficial
effects.
In addition to use as a wireline treating fluid injection chamber,
the apparatus described in FIGS. 13 and 14 is also capable of use
with the implosive pulse generator 30 of this invention in
combination with cement squeezing or plugging operations to seal
off production of undesired fluids, patching leaks in casing, etc.,
at a minimum of trouble and expense.
SECONDARY RECOVERY
It has been found that in many secondary recovery projects, e.g.,
water drive from an injection well to a producing well implosive
reaction pulses can assist removal of oil trapped in minute pore
spaces. Accordingly, the apparatus taught according to this
invention has further application by placement within an injection
well or alternately in both injection well and producing wells. In
the latter instance, it is highly possible to cause cyclic
pulsation through the formation by proper timing of the implosive
pulse generators. For such use the producing well apparatus would
provide means for lifting the fluids from the well to the
surface.
It is entirely within the purview of this invention that in gas
drive or underground combustion recovery techniques that implosive
reaction pulses generated in accordance with this invention be
utilized to assist gas flow or maintain combustion within the
formation respectively.
Although I have described the apparatus of this invention as a
removable type apparatus, i.e., using tubing or wireline, the
apparatus is also capable of being permanently anchored or formed
as a part of a permanent well completion apparatus capable of being
placed into use at the demand of the operator. Accordingly, anchor
slips may be formed as a part of the apparatus, as is well known to
those skilled in the art. In that event the upper packing member 60
is usually retained in a permanently sealed position. As heretofore
described, a separate source of high pressure fluid is introduced
into the generator 30 to cause operation.
In still another embodiment wherein valve 40 is allowed to operate,
the device 30 may be anchored at a particular location and fluids
pumped through the device and thus cause an alternating series of
the implosive reactions, this being similar to the occurrence when
device 30 is pulled upward against fluid in a well, as in swabbing.
That is, actuating fluids are pumped downward through annulus space
15 and thence through passageway 67 into cylinder space 68 against
the top of sleeve or piston 74. This will cause an implosive
reaction as previously described which in turn permits periodic
release of the pressure fluid existing above valve 40. The periodic
release of pressure fluid through valve 40 coincides with the
frequency of the standing wave of the particular harmonic of the
fundamental wave frequency in the fluid used below the generator
unit 30. Additionally, the particular harmonic is created in
accordance with the length of the unit 30 from the bottom of the
well and the reflected quarter of a wave therefrom.
SEISMIC EXPLORATION
In seismic exploration and prospecting, a great many methods have
been devised for furnishing the vibrational signal for reflection
or refraction from or through geological formations deep within the
earth in order to determine the depth and the degree and direction
of slope of subsurface strata.
Among these methods the use of explosives has been the most
popular. However, in the use of explosives for providing the energy
for seismic profile signaling, there has been considerable
disadvantages in their use particularly as to marine seismic
prospecting wherein destruction has been caused to marine life.
Many other methods have been devised to eliminate the use of
explosives in marine seismic profiling, among them being the use of
electrical sparks, gas exploders, etc., but the use of some of
these methods does not provide enough vibrational energy to where
the deeper subsurface strata is delineated or profiled as to its
depths and contour.
By the proper use of implosions and the reactive implosive pulses
seismic vibrational signals may be produced that will approach in
strength those produced by explosives and these deeper strata may
be profiled with less expense and destruction to the surroundings
in which the seismic signaling is done as compared to the use of
explosives.
In the use of implosion wave generator 30 of FIG. 4, outer casing
10 may be towed behind a ship at a preselected depth in water and
with device 30 anchored at a fixed position in the casing, the
pressure of the water upon device 30 producing implosions and
resultant implosive reactions whose sonic or vibrational energy
would penetrate the earth to which the sea water was acoustically
coupled and the seismic signals reflected from or refracted through
the various subsurface strata could be detected and recorded by
geophones towed behind the boat at various locations, as in
conventional marine seismic profiling.
If it was desired to provide a continuous implosive wave marine
seismic profiler that could utilize certain proportions of the
implosive pulses for assisting in creating other implosions, then
device 30 could be located at a proper location within casing 10,
which could be the center, and at certain towing speeds reflective
pulses of a multiple of a quarter of a wave length or one of its
harmonics of the two lengths of the pipe on either side of device
30 would set up standing wave conditions that would assist in
continuing the implosive pulses within close tolerances as to
periodic frequencies.
As an operating means, if desired, the forward end of casing 10
could be closed and have attached thereto liquid and sonic wave
supplying means 162 and the actuation of the implosions could be
sonic waves of any desired type and the implosions could be a
modulating and intensifying means to the actuating sonic waves.
In location with enough water depth, casing 10 with device 30
therein could be vertically suspended from the ship or other
buoyant member and actuation of the implosive reaction generator 30
could be by repeated lift ups and drops of the device within casing
10, or the operation could be by connection to sonic generator 162
as described above in relation to towing the casing and its device
in a substantially horizontal plane.
The above described use of implosions in marine seismic profiling
is not meant to limit the use of implosions to marine use, for
implosions could be used for onshore use by various means, such as
enclosing the bottom of casing 10 with a heavy plate which would
acoustically couple to the earth and thus send vibrational energy
waves into the earth for use in seismic profiling.
Such a use of acoustically coupling a heavy casing member 10 to the
earth and sending seismic signals into the earth as of many of the
various types of sonic or energy carrying waves that may be
produced from the sonic wave generators as are disclosed in my
parental application Ser. No. 665,995, filed June 17, 1957 now U.S.
Pat. No. 3,302,720, of which this application has a
continuation-in-part effect, was tested in the use of a small pilot
model of the apparatus as shown in parent application Ser. No.
296,038 filed June 27, 1952, now U.S. Pat. No. 2,866,509 before
several individuals, among them being petroleum and reservoir
engineers, wherein it was seen that with the casing member 10 being
located some 60 feet away from the sonic wave generating apparatus
means, vibrational signals could be detected coming from the heavy
casing member 10 for a considerable distance.
Further, it was found where sonic standing wave conditions of its
fundamental wave length or one of its harmonics was imposed on the
system and then a controlled modulation of one resonating sonic
wave out of a great many resonating waves was caused to be
intermittently applied to the system by the sonic wave generating
apparatus, the resultant intense vibrational shock wave which could
be clearly detected from the other sonic waves resonating through
the earth could be received at a much further distance than could
the main body of the sonic waves resonating through the earth. It
was also determined that the greater seismic signaling effect was
obtained where sonic wave energy was allowed to build up and
accumulate in the system for a controlled period of time and then
one wave had sonic wave energy and fluid withdrawn in a
cavitational or implosive effect during the rarefaction portion of
only the one wave cycle and the more substantially instantaneous
and the greater the amount of cavitational or implosive effect the
greater and more far reaching the resultant reactive shock wave
vibrational seismic signaling.
Several months of experimentation was conducted with electronic
timing instrumentation with the use of the above various types of
modulated sonic and vibrational waves as to their velocity or time
travel through various fluids wherein a particular recognizable
type of modulated wave was timed at its creation moment in the
sonic wave generating apparatus, timed as to its reflection time
interval from the end of the casing 10 approximately 60 feet away
through various types of fluids such as water, crude oil, various
amounts of gases that were miscible or absorbable in the water or
the oil, which gases could be caused to come in and out of the
liquids during rarefactions of the resonating sonic waves and/or
during rarefactions or cavitations of the one sonic wave being
modulated out of the many sonic waves resonating in the system.
Also tested, as above, was the time interval between the moment of
creation of a particular type of modulated sonic or vibrational
wave, as was recognizable by the phase angle at which it being
modulated on the one sonic wave out of the many sonic waves whose
energy was being accumulated in the system, and its reflection back
through external lines containing various fluids including
liquefiable gases of equal lengths with that which connected casing
10 with the sonic wave generating means 162.
Some of the findings of the considerable experimentation was that a
certain type or form of intense modulated sonic or vibrational wave
could be easily recognized from the other sonic or vibrational
waves and timed as to amount of length that the modulated wave
traveled through a particular type of fluid. It was found that
water appeared to allow the greatest velocity of wave travel in the
liquids tested and the slower velocity of wave travel through crude
oil could be timed in its relationship to sonic wave travel through
water. It was also found that where gases were introduced into the
liquids, as by use of carbon dioxide with water or mixtures of
methane and propane with crude oil, that proportionately as the
increase of gas introduced in proportion to the amount of liquid
used in the fluid system up to the saturation point of the gas into
the liquid at the pressure maintained on the system above
atmospheric pressure, then proportionately as to the velocity of
sonic wave travel through the particular gas used and the amount of
its relationship to the amount of the liquid used the velocity of
sonic waves would be slowed down in its time travel by that
proprotionate amount. Thus it was found that where a particular
liquid was the acoustic coupling means from a sonic generating
means 162 to the end of a casing or member 10 and a peculiar or
particular type of sonic or vibrational wave is created by
modulating one wave from built up or accumulating sonic standing
wave energy of a great many waves, then this one wave may be
recorded at its moment of creation, go through the many wave
lengths of the prime fundamental or one of its harmonics that is
resonating under standing wave conditions between sonic wave
generator 162 and the bottom end of casing 10, be reflected back
through and on the standing waves to its source at 162 and be timed
as to its travel from creation to reflection point and return.
Thus, by the above, as is well known, where the depth of the well
bore of casing 10 is unknown it may be readily ascertained, where
the velocity of sound in the particular liquid being used is known,
by the recorded elapsed time between the time of creation of the
modulated wave and its return.
When the large field model sonic wave generating apparatus as
depicted in my co-pending application Ser. No. 406,045 filed Oct.
12, 1973 which is a continuing development of the small apparatus
discussed as to its use in 1952, was placed into use in 1956 on
waterflood injection wells and for fracture treating of productive
formations considerable of the findings of experimentations of 1952
were substantiated in the field, as follows:
When the sonic generating apparatus 162 as of Ser. No. 406,045
filed Oct. 12, 1973 was placed upon an injection well and operated
several hours with the use of sonic waves resonating in the well
bore under standing wave conditions with the controllable
modulation of one wave out of many sonic waves that were adding
energy to the system, reflections of the modulated wave could be
detected coming back onto sonic wave generator 162. With the
continued use of sonic wave generator 162 with the modulation of
the sonic wave being of a type created by heavy cavitational or
implosive effects which by proper control were able to gather up
by-passed by the waterflood oil and gas in the formation, then
there would gradually begin a heavier reflection of the modulated
wave from the formation until a level of detectable reflected wave
energy would be obtained which would continue until shut down of
the wave generator 162. It could be noted and detected that there
were two reflections coming back to the well head, one a
substantially uniform one that began after starting use of the
modulated sonic waves in the well bore and another a later arriving
in time reflected wave that increased to a heavy beat as the
reflecting wall of gas and oil in the formation was built up. Thus
recording means could not only record the distance to the bottom of
the well bore but it could also delineate and give the underground
distance to the progressing oil and gas front upon which the
waterflood was pushing.
It was also found that the modulating sonic wave beats could be
detected at some of the production wells, particularly those where
water had broken through. Where a production well was gasing
heavily the modulated sonic wave beat would be totally
undetectable, showing that the gas in the interstices of the
formation was reflecting or attenuating the sonic or vibrational
wave energy. Those wells producing oil with very little free gas
allowed a faintly detectable beat at the well head from the
modulated sonic wave in the drive water to be recognized as coming
through the banked up oil and gas front in the formation.
Later, in early 1957, when an oil producing well was being
fractured and treated by the modulated sonic waves of the apparatus
162 as of Ser. No. 406,045 filed Oct. 12, 1973, and oil was used as
the treating fluid, it was noticed that stronger beats were
discernable and detectable at the well heads of offset oil
producing wells then had been the case where the apparatus 162 was
used on a water injection well and the change of sonic wave
transmitting medium, as at the banked up oil and gas front, was
between the well inputting the sonic waves and a well receiving
seismic signals.
It could be seen from the above discussed results and observations
that by acoustically coupling a sonic wave generator to a fluid
containing formation, preferably liquid, that a change of medium or
type of fluid could cause a change of signal strength in the
different types of fluid mediums, or at a discontinuance thereof,
so that geophones or like sensitive instruments for detecting and
recording seismic signals could be used in contact with the earth
at varying locations surrounding the well into which the sonic
waves were being input and delineation or profiling of boundaries
of fluids or fluid containing formations could be recorded and
outlined as to their extent.
It was also obvious that the above methods and processes of
outlining and profiling of various bodies or formations containing
fluids as to the types or extent of the fluids as known by the
seismic signal strength received and velocity or time travel
between the recognizable seismic vibrational beats in different
areas of the earth above the formation and/or between varying
locations on the earth and the time at which the seismic signal was
sent from the seismic signal source, all of which signals could be
recorded on graphs for use as desired, could also be used to
profile the subsurface contours of the fluid containing formations
or surrounding formations or strata, by the seismic signals and/or
the reflections or refractions therefrom received at varying
locations on the earth or water above, as for instance by
measurement of the distance between beats of the seismic signals
received from a like seismic vibrational wave transmitting
medium.
Thus it is possible to profile, delineate and outline substantially
the extent of fluid containing reservoirs, the approximate
boundaries of various types or mixtures of fluids contained in the
reservoirs, as well as the subsurface contours of the fluid
containing formations or the strata surrounding said fluid
containing formations, with access being given to a fluid
containing subsurface formation, preferably liquid, to which a
seismic signaling means or apparatus may be acoustically
coupled.
When the seismic vibrational wave signaling device is set at the
surface as of 162 of FIG. 11, it may be any type or of sonic wave
generator as described in detail in my co-pending application Ser.
No. 406,045 filed Oct. 12, 1973, that produce a pulse, periodic
wave or modulated sonic wave and, if desired, device 30 of this
application may be located adjacent the fluid containing formation
and used in conjunction with apparatus 162 whereby any of the types
of sonic waves from 162 may be the actuating means for operation of
device 30 which may be a transforming, transferring, intensifying
or modulating means for the sonic waves from generator 162.
On the other hand, if desired, or if it be dictated by conditions,
device 30 may be the sole source of seismic vibrational signaling
and be actuated by any of the other means disclosed in this
application.
Thus it may be seen that extremely vital and valuable information
may be obtained by use of the various seismic signaling, profiling
and recording methods and processes disclosed in this application
and, if desired, this seismic delineating and profiling information
may be secured, recorded and retained during sonic wave secondary
recovery or formation treating operations with no necessity of
halting or delaying these operations to obtain the desired seismic
outlining or profiling data as the seismic vibrational signals used
to obtain the data would be side effects or sonic wave vibrational
energy being attenuated during the sonic wave fluid recovery or
formation treating methods or processes.
It may also be discerned that among the various methods and
processes described hereinbefore of the use of implosions or
substantially instantaneously produced rarefactions in that portion
of the well bore packed off from the rest of the bore, but in
communication with the fluid containing subsurface formation, as a
source of energy for seismic signaling, may be those field tested
methods hereinabove described wherein a substantially instantaneous
rarefaction or cavitation is imposed on a sonic wave and in so
being utilized will form a modulated rarefaction or implosion of
variable characteristics by varying the phase angle of use of the
rarefaction impulse in its relationship to the rarefaction portion
of the sonic wave as disclosed and described in considerable detail
in my co-pending application Ser. No. 406,045 filed Oct. 12, 1973
with established continuity being maintained therein from my
original parent application Ser. No. 241,647 filed Aug. 13, 1951
now U.S. Pat. No. 2,796,129.
There are considerable advantages and improvement in the last above
cited methods and processes of the use of rarefaction impulses or
implosions for seismic signaling, besides the already enumerated
one as to the ability to be able to produce sources of seismic
energy of variable characteristics so that the recorded seismic
signals at adjacent well bores, at the surface surrounding the well
bore or back upon the well bore from which the seismic energy
originates within the packed off section of the well bore may have
recognizable recordings so that the arrival times of the recorded
signals may be concisely known and the location or presence is
shown of various types of fluids or formations in the area
surrounding the well bore in which the rarefactions or implosions
are produced.
In the use of these advances found to be of proven worth in
considerable field testing of the use of surging from fluids of
subsurface formations into created rarefactions within packed off
portions of subsurface well bores as a source of seismic energy, it
has been found that the energy from these created implosions or
rarefractions decreases outward from the well bore, so that where
fluids or formations are at large subsurface distances from the
rarefaction source of these seismic signals in the fluids within
the lower packed off portion of the well bores they often will not
record as proficiently as would be desired at the receiving station
or stations.
It has been found in numerous instances of use that where a sonic
wave or one of its harmonics was allowed to assume a standing wave
or resonant condition within the fluid in the packed off portion of
the well bore and in the fluid containing formation in
communication therewith, that the variably phased cavitations or
rarefactions impressed as a modulation thereon would travel to
great distances within certain types of fluids in the fluid
containing subsurface formation and become a source of seismic
energy which could be utilized and recorded as seismic signals to
delineate the extent, location or presence of various types of
subsurface fluids or strata. Any desired use of one or more of
these implosions or rarefactions and any desired intervals of
timing of the phase angle impressing of one or more of these
modulations upon the transporting sonic wave into the fluids within
the lower packed off portion of the well bore allows corresponding
recognizable characteristics of recorded seismic signal at the
receiving station or stations.
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