U.S. patent number RE32,345 [Application Number 06/622,957] was granted by the patent office on 1987-02-03 for packer valve arrangement.
This patent grant is currently assigned to Completion Tool Company. Invention is credited to Edward T. Wood.
United States Patent |
RE32,345 |
Wood |
February 3, 1987 |
Packer valve arrangement
Abstract
A valve system for use in inflating packers mounted on mandrels
is disclosed. The valve system uses one or more valves to permit,
through the use of seals, the flow of fluid from the interior of a
tubular mandrel to the interior of the inflatable packer when
pressure applied in the mandrel exceeds at least a minimum
pressure. In two embodiments, inflation of the packer beyond a
given pressure is prevented. In all embodiments, the differential
pressure across reciprocating seals is minimized through exposure
of one or both sides, directly or indirectly, to the external
pressure of the mandrel and packer.
Inventors: |
Wood; Edward T. (Kingwood,
TX) |
Assignee: |
Completion Tool Company
(Houston, TX)
|
Family
ID: |
27020059 |
Appl.
No.: |
06/622,957 |
Filed: |
June 21, 1984 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
407898 |
Aug 13, 1982 |
04420159 |
Dec 13, 1983 |
|
|
Current U.S.
Class: |
277/333; 166/151;
166/187 |
Current CPC
Class: |
E21B
33/127 (20130101) |
Current International
Class: |
E21B
33/127 (20060101); E21B 33/12 (20060101); E02D
005/00 (); E21B 033/12 (); F16J 015/46 () |
Field of
Search: |
;277/34,34.3,34.6
;166/151,187 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Ward; Robert S.
Claims
What is claimed as invention is:
1. In a tubular system having
a .[.hollow.]. tubular mandrel;
.[.a packer.]. .Iadd.an inflatable packing element
.Iaddend.attached to the mandrel at one end;
a valve collar mounted on the other end of the mandrel, the other
end of the .[.packer.]. .Iadd.packing element .Iaddend.being
attached to the .Iadd.valve .Iaddend.collar and the .Iadd.valve
.Iaddend.collar being in fluid communication with the .[.packer.].
.Iadd.packing element .Iaddend.by .[.a.]. passage .Iadd.means
.Iaddend.and the .Iadd.valve .Iaddend.collar also being in fluid
communication with the interior .Iadd.bore .Iaddend.and .Iadd.the
.Iaddend.exterior of the mandrel;
a valve system mounted .[.on the mandrel.]. .Iadd.in the valve
collar.Iaddend., the valve system being in fluid communication with
the .[.packer.]. .Iadd.packing element .Iaddend.and the interior
.Iadd.bore .Iaddend.and .Iadd.the .Iaddend.exterior of the mandrel,
the valve system including at least one valve .Iadd.means
.Iaddend.with at least one reciprocating .[.member.]. .Iadd.valve
element .Iaddend.and .[.a.]. stop means for preventing
reciprocation of the reciprocating .[.member.]. .Iadd.valve element
.Iaddend.prior to the application of at least a predetermined
pressure difference to the reciprocating .[.member.]. .Iadd.valve
element.Iaddend., the reciprocating .[.member.]. .Iadd.valve
element .Iaddend.being located .[.at one end of.]. .Iadd.in one
position in .Iaddend.the .[.passage.]. .Iadd.one valve means
.Iaddend.when the stop means prevents reciprocation, the
reciprocating .[.member.]. .Iadd.valve element .Iaddend.having at
least two seals thereon for preventing the flow of fluid from
either side of the .[.reciprocating member around the member.].
.Iadd.seals .Iaddend.to the passage .Iadd.means.Iaddend.;
the improvement comprising:
first means independent of the seals for permitting the flow of
fluid from the interior .Iadd.bore .Iaddend.of the mandrel to one
side of one seal .[.of.]. .Iadd.on .Iaddend.the reciprocating
.[.member.]. .Iadd.valve element.Iaddend.; and
second means independent of the seals for permitting the flow of
fluid from the exterior of the mandrel to oppositely facing
.[.surface.]. .Iadd.side .Iaddend.of the other seal .[.of.].
.Iadd.on .Iaddend.the reciprocating .[.member.]. .Iadd.valve
element.Iaddend.; and
third means independent of the seals for .[.equalizing the pressure
on the other side of each of.]. .Iadd.permitting the flow of fluid
to a location between .Iaddend.the seals .Iadd.for equalizing the
pressure across the seals .Iaddend.to substantially .[.that of.].
.Iadd.the pressure at .Iaddend.the exterior of the mandrel
.Iadd.and to the pressure in the interior bore of the
mandrel.Iaddend.. .[.
2. A tubular system for use in packing off a well bore,
comprising:
a hollow tubular mandrel;
a packer attached to said mandrel at one end of said mandrel;
a valve collar mounted on the other end of said mandrel, the other
end of said packer being attached to said collar and having a
passageway therethrough, and said collar being in fluid
communication with said packer and the interior and exterior of
said mandrel by said passageway;
said passageway having enlarged portions in said collar;
a valve system mounted in said enlarged portions, said valve system
including three valves;
the first of said valves being mounted in the first of said
portions and having a reciprocating member and a stop means for
preventing reciprocation of said reciprocating member prior to the
application of at least a predetermined difference in pressure
between one side of said reciprocating member and the other side,
said reciprocating member being located at one end of a first part
of said passageway when said stop means prevents reciprocation and
having at least two seals thereon for preventing the flow of fluid
from either end of said reciprocating member around the member to
said first passageway part;
said first valve being in fluid communication with a second part of
said passageway in fluid communication with said interior of said
mandrel on one side of said reciprocating member;
said first valve being in fluid communication with said exterior of
said mandrel on the other side of said reciprocating member;
and
the second of said valves having check means for permitting the
flow of fluid from said exterior of said mandrel to said first part
of said passageway when the pressure in said mandrel exceeds the
pressure in said second portion..]. .[.
3. The system of claim 2, wherein said second portion includes a
first bore opening to said exterior of said mandrel and said second
valve is located in said first bore..]. .[.4. The system of claim
3, wherein said second valve uncludes:
a head adapted to connect to said first bore;
a seal mounted on said head and sealingly engaging the walls of
said first bore and said head; and
said check means is mounted in said head..]. .[.5. The system of
claims 2, 3 or 4 wherein the remainder of said second portion is
filled with a liquid..]. .[.6. The system of claims 1, 2, 3 or 4
wherein;
said third valve is mounted in a third of said portions, said third
portion being in fluid communication with said exterior of said
mandrel and a third part of said passageway in fluid communication
between said second portion and said third portion and a fourth
part of said passageway in fluid communication with said
packer;
said third valve including
first seal means for preventing fluid communication between said
third portion and said exterior of said mandrel, and
second seal means for preventing fluid communication between said
third part and said fourth part when the pressure in said fourth
part is greater
than the pressure in said third part..]. 7. A tubular system for
use in packing off a well bore, comprising:
a .[.hollow.]. tubular mandrel;
.[.a packer.]. .Iadd.an inflatable packing element
.Iaddend.attached to said mandrel at one end of said mandrel having
an interior portion separated from said mandrel .Iadd.so as to
receive inflating fluid .Iaddend.and .[.an.]. inlet .Iadd.means to
admit fluid .Iaddend.to said interior portion;
a valve collar mounted on other end of said mandrel and having
.[.a.]. passageway .Iadd.means .Iaddend.therethrough, the other end
of said .[.packer.]. .Iadd.packing element .Iaddend.being attached
to said .Iadd.valve .Iaddend.collar, and said .Iadd.passageway
means in said valve .Iaddend.collar being in fluid communication
with said inlet .[.to said packer.]. .Iadd.means of said packing
element.Iaddend., .Iadd.with .Iaddend.said interior portion of said
.[.packer.]. .Iadd.packing element .Iaddend.and .Iadd.with
.Iaddend.the interior .Iadd.bore .Iaddend.and .Iadd.the
.Iaddend.exterior of said mandrel .[.by said passageway.].;
.Iadd.a valve pocket system in .Iaddend.said passageway .Iadd.means
.Iaddend.having enlarged portions in said .Iadd.valve
.Iaddend.collar, including
.[.a.]. first .[.portion.]. .Iadd.valve pocket means .Iaddend.in
fluid communication .[.with a first part of said passageway in
fluid communication.]. with .Iadd.the .Iaddend.interior .Iadd.bore
.Iaddend.of said mandrel,
.[.a.]. second .[.portion.]. .Iadd.valve pocket means .Iaddend.in
fluid communication with .[.said external part.]. .Iadd.the
exterior .Iaddend.of said mandrel and .[.a second part of said
passageway in fluid communication with said first portion.].
.Iadd.said first valve pocket means.Iaddend., and
.[.a.]. third .[.portion.]. .Iadd.valve pocket means .Iaddend.in
fluid communication with .[.a third part of said passageway in
fluid communication with said second portion, said third portion.].
.Iadd.said second valve pocket means and .Iaddend.also .[.being
in.]. .Iadd.having separate .Iaddend.fluid communication .[.with a
fourth part of said passageway in fluid communication with said
interior at said packer and a fifth part of said passageway in
fluid communication with said inlet to said packer.]. .Iadd.paths
to said inlet means and to the interior of said packing
element.Iaddend.;
.[.a valve system mounted in said enlarged portions;
said valve system including three valves;.].
.Iadd.valve means in said first and third valve pocket means and
operable in response to pressure in said passageway means;
.[.the second of said valves being mounted in said second portion
and having.]. .Iadd.valve means in said second valve pocket means
for controlling the flow of fluid from the interior bore of said
tubular mandrel to said inlet means including a shear valve member
in said second valve pocket means, said shear valve member being
.Iaddend.a reciprocating member .Iadd.movable between a first and
second position .Iaddend.and .[.a stop.]. .Iadd.shear
.Iaddend.means for preventing reciprocation of said reciprocating
member .Iadd.in said first position .Iaddend.prior to the
application of at least a predetermined difference in pressure
between one side of said reciprocating member and the other side
.Iadd.of said reciprocating member.Iaddend., said reciprocating
member being located at one end of said .[.second part.].
.Iadd.second valve pocket means .Iaddend.when said .[.stop.].
.Iadd.shear .Iaddend.means prevents reciprocation and having at
least two seals thereon for preventing the flow of fluid from
either end of said reciprocating member around said
.Iadd.reciprocating .Iaddend.member to said third .[.part.].
.Iadd.pocket
valve means.Iaddend.. 8. The system of claim 7 wherein:
said .[.second valve.]. seals .Iadd.on said shear valve member
.Iaddend.are mounted to .[.avoid prevention of.]. .Iadd.permit
.Iaddend.flow between said .[.second portion and said third portion
through said third part when said stop means permits
reciprocation.]. .Iadd.first valve pocket means and said third
valve pocket means when said reciprocating member is in
said second position.Iaddend.. 9. The system of claims 7 or 8
wherein:
.Iadd.said valve means disposed in said first valve pocket means
include:
a reciprocating valve member movable between a first and second
position and normally resiliently biased to the first position,
.Iaddend.
.[.said first valve is mounted in said first portion,
said first valve including.].
first seal means for preventing fluid communication between said
.[.first portion and said.]. .Iadd.second valve pocket means and
the .Iaddend.exterior of said mandrel, .Iadd.in said first
position; .Iaddend.and
second seal means .Iadd.on said resiliently biased reciprocating
valve member .Iaddend.for preventing fluid communication between
.[.said first part and said second part.]. .Iadd.the interior bore
of said mandrel and said second valve pocket means .Iaddend.when
the pressure in said .[.second part.]. .Iadd.first valve pocket
means .Iaddend.is greater than the pressure in .[.said first
part.]. .Iadd.the interior of the
mandrel.Iaddend.. 10. The system of claims 7 or 8 wherein:
.[.said third portion is in fluid communication with said exterior
of said mandrel;.].
said third valve .[.is mounted.]. in said third portion and
.Iadd.said valve means disposed in said third valve pocket means
.Iaddend.includes a .[.second.]. reciprocating .Iadd.valve
.Iaddend.member .[.and a third reciprocating member connected by a
stem and a second.]. .Iadd.movable between a first and second
position, .Iaddend.stop means .Iadd.in said third valve pocket
means .Iaddend.for preventing reciprocation of said reciprocating
.[.members.]. .Iadd.valve member .Iaddend.prior to the application
of at least a predetermined pressure difference between one side of
said .[.second.]. reciprocating .Iadd.valve .Iaddend.member and the
oppositely facing side of said .[.third.]. reciprocating
.Iadd.valve .Iaddend.member, said .[.second.]. reciprocating
.Iadd.valve .Iaddend.member having two seals thereon and being
positioned .[.in said third portion.]. .Iadd.in a spaced apart
relationship .Iaddend.so that at least one of said seals prevents
fluid flow between said .[.fourth part and said third portion.].
.Iadd.third valve pocket means and said communication path to the
interior of said packing element .Iaddend.when said stop means
prevents reciprocation .Iadd.in said first position.Iaddend.;
said .[.third.]. reciprocating .Iadd.valve .Iaddend.member
.[.includes.]. .Iadd.in said third valve pocket means having
.Iaddend.third seal means .Iadd.along its length .Iaddend.for
preventing fluid communication between .[.a portion of said third
portion and said.]. .Iadd.said third valve pocket means and the
.Iaddend.exterior of said mandrel; and
said .Iadd.first and second .Iaddend.seals thereon being spaced for
preventing .[.the flow of.]. fluid .Iadd.flow .Iaddend.from either
.[.side of said second reciprocating member to said third part.].
.Iadd.the inlet means or the interior of the packing means
.Iaddend.after said .[.second.]. stop means .[.no longer prevents
reciprocation,.]. .Iadd.releases said reciprocating valve member in
said third valve pocket means and said reciprocating valve member
moves to said second position .Iaddend.said seals .Iadd.and
reciprocating valve member in said third valve pocket means
.Iaddend.being positioned to permit flow from said .[.third part to
said fifth part about said stem.]. .Iadd.second valve pocket means
to said inlet means .Iaddend.when said .[.second.]. reciprocating
.Iadd.valve .Iaddend.member .Iadd.in said third valve pocket means
.Iaddend.is .[.prevented from reciprocating by said second stop
means.]. .Iadd.in said first position.Iaddend.. 11. The system of
claim 10 wherein there is further included .[.a small,.]. relief
passage .Iadd.means .Iaddend.between said .[.two.]. .Iadd.first and
second .Iaddend.seals of said .[.second.]. reciprocating
.Iadd.valve .Iaddend.member and one of the ends of said
.[.second.]. reciprocating
.Iadd.valve .Iaddend.member. 12. .[.A tubular member.]. .Iadd.An
inflatable packer .Iaddend.for use in a bore, comprising:
.Iadd.a tubular mandrel; .Iaddend.
.[.a packer.]. .Iadd.an inflatable packing element
.Iaddend.attached to said mandrel at one end of said mandrel
.Iadd.and .Iaddend.having an interior portion separated from said
mandrel;
a valve collar mounted on the other end of said mandrel and having
a passageway therethrough, the other end of said packer being
attached to said .Iadd.valve .Iaddend.collar, and said .Iadd.valve
.Iaddend.collar .[.being in.]. .Iadd.having means providing a
.Iaddend.fluid communication .Iadd.path .Iaddend.with said interior
of said .[.packer by a passage.]. .Iadd.packing element
.Iaddend.and .Iadd.with .Iaddend.the interior .Iadd.bore
.Iaddend.and .Iadd.the .Iaddend.exterior of said mandrel;
said .[.passage.]. .Iadd.fluid communication path .Iaddend.having
at least one .[.enlarged portion forming a part.]. .Iadd.valve
pocket means .Iaddend.in said .Iadd.valve .Iaddend.collar;
.[.a valve system mounted in said enlarged portion, said valve
system being.]. .Iadd.valve element means in said valve pocket
means .Iaddend.in fluid communication with the interior of said
.[.packer.]. .Iadd.packing element .Iaddend.and the interior
.Iadd.bore .Iaddend.and .Iadd.the .Iaddend.exterior of said
mandrel.[.;.]. .Iadd.and including means responsive to a
differential pressure between the pressure exterior to the valve
collar and the pressure within the packing element for closing off
fluid flow in said communication path to said packing element;
.Iaddend.
said valve collar being .[.adapted to be inserted at.].
.Iadd.attached to .Iaddend.the end of said mandrel that is last to
enter the bore. .[.13. A tubular system for use in packing off a
well bore, comprising:
a hollow tubular mandrel;
a packer attached to said mandrel at one end of said mandrel having
an interior portion separated from said mandrel and an inlet to
said interior portion;
a valve holder mounted on other end of said mandrel and having a
passageway therethrough, the other end of said packer being
attached to said valve holder, and said valve holder being in fluid
communication with said inlet to said packer and the interior and
exterior of said mandrel by said passageway;
said passageway having an enlarged portion in said valve holder,
said portion being in fluid communication with:
a first part of said passageway in fluid communication with
interior of said mandrel,
said external part of said mandrel, and
a second part of said passageway in fluid communication with said
inlet to said packer;
a valve system mounted in said enlarged portion, said valve system
including at least one valve, said valve being mounted in said
portion and having a reciprocating member and a stop means for
preventing reciprocation of said reciprocating member prior to the
application of at least a predetermined difference in pressure
between one side of said reciprocating member and the other side,
said reciprocating member being located at one end of said portion
when said stop means prevents reciprocation and having at least two
seals thereon for preventing the flow of fluid from either end of
said reciprocating member around said member to said second
part;
each of said seals being exposed on one side thereof to fluid from
said
second part..]. .Iadd.14. An inflatable well packer for use in a
well bore traversing earth formations where the well packer has a
tubular mandrel, an inflatable packer element on said tubular
mandrel with one end of the packer element attached to the mandrel
and a valve collar means attached to the other end of the packer
element and mandrel,
the improvement comprising:
valve means and passage means in said valve collar means for
selectively admitting fluid from the interior bore of the tubular
mandrel to the interior space between said packer element and said
tubular mandrel, said valve means including a first valve having
spaced apart seal means on an elongated first valve element
slidably received in said valve collar means for movement between
first and second positions, said seal means in a first position of
said valve element straddling a section of the passage means
leading to said interior space between said packer element and said
tubular mandrel,
release means for releasably retaining said first valve element in
said first position and releasable upon the application of
predetermined pressure differential across said seal means to move
said valve element to said second position,
said valve element on one side of said seal means having access to
the pressure exterior of the valve collar and having access on the
other side of said seal means to the pressure in a portion of the
passage means leading to the interior bore of said tubular mandrel
so as to pressure balance said first valve element across said seal
means between the interior bore of the tubular mandrel and the
exterior of the valve collar means. .Iaddend. .Iadd.15. An
inflatable well packer for use in a well bore which traverses earth
formations wherein the lower end of such well packer is intended to
enter the well bore first, and including
a tubular mandrel adapted for coupling a string of pipe,
an inflatable packer element disposed on said tubular mandrel and
attached at its lower end to said tubular mandrel in a fluid tight
relationship,
valve collar means attached to the upper end of said packer element
and said tubular mandrel so as to have access to the pressure in
the well bore above the inflatable packer element,
said valve collar means including at least one releasable valve
means and passage means where said releasable valve means is in
fluid communication with the interior bore of said tubular mandrel,
the interior of the inflatable packer means and the exterior of
said valve collar means above said packer element, said releasable
valve means being normally retained in a first position and being
releasable to a second position with respect to said passage means
upon the application of a predetermined pressure differential
between the fluid in the interior of the packer element and the
fluid at the exterior of the valve collar means to move said
releasable valve means between said first and second positions.
.Iaddend. .Iadd.16. The well packer as defined in claim 15 where
said releasable valve means includes a shear pin and movable valve
element..Iaddend.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to packer inflation systems and more
particularly to the valves which control the inflation of
packers.
2. Description of the Prior Art
The control of the inflation of well packers is important to obtain
integrity between the packer and the well bore for purposes of
working within the bore. It is known in the art to inflate packers
by various mechanisms. See, for example, U.S. Pat. No. 3,503,445,
issued Mar. 31, 1970, to K. L. Cochran et al. entitled "Well
Control During Drilling Operations"; U.S. Pat. No. 3,351,349,
issued Nov. 7, 1967, to D. V. Chenoweth, entitled "Hydraulically
Expandable Well Packer"; U.S. Pat. No. 3,373,820, issued Mar. 19,
1968, to L. H. Robinson, Jr. et al, entitled "Apparatus for
Drilling with a Gaseous Drilling Fluid".
In U.S. Pat. No. 3,437,142, issued Apr. 8, 1969, to George E.
Conover, entitled "Inflatable Packer for External Use on Casing and
Liners and Method of Use", there is disclosed an inflatable packer
for external use on tubular members such as casings, liners, and
the like. A valving arrangement is disclosed therein for containing
fluid within the interior of the inflatable member after it has
been inflated to prevent its return to the tubular member.
Arrangements of valving have been known in the prior art to prevent
further communication between the interior of the tubular member
and the interior of the inflatable element after the inflatable
element has been inflated and set in a well bore. See, for example,
U.S. Pat. No. 3,427,651; issued Feb. 11, 1969, to W. J. Bielstein
et al, entitled "Well Control"; U.S. Pat. No. 3,542,127, issued
Nov. 24, 1970, to Billy C. Malone, entitled "Reinforced Inflatable
Packer with Expansible Back-up Skirts for End Portions"; U.S. Pat.
No. 3,581,816, issued June 1, 1971, to Billy C. Malone, entitled
"Permanent Set Inflatable Element"; U.S. Pat. No. 3,818,922, issued
June 25, 1974, to Billy C. Malone, entitled "Safety Valve
Arrangement for Controlling Communication Between the Interior and
Exterior of a Tubular Member"; and U.S. Pat. No. 3,776,308, issued
Dec. 4, 1973, to Billy C. Malone, entitled "Safety Valve
Arrangement for Controlling Communication Between the Interior and
Exterior of a Tubular Member".
Inflatable packers have also been used in other operations, such as
sealing the annular space between a jacket and a piling. See for
example U.S. Pat. No. 4,063,427, issued Dec. 20, 1977, to Erwin E.
Hoffman, entitled "Seal Arrangement and Flow Control Means
Therefor".
The seals that are used in valves, such as in Malone, are usually
hardened rubber. Such rubber tends to extrude under extreme
pressure differential across the rubber and cause friction between
rubber and metal that adversely affects valve operation. None of
the prior art, however, provides for mechanism for equalizing
pressures across the seals of the valves used to inflate packers to
prevent such extrusion.
SUMMARY OF THE INVENTION
The present invention utilizes a unique arrangement of sealing
mechanisms in conjunction with a valve or valves to permit the
inflation of an inflatable packer element while at the same time
equalizing pressure around the rubber seals of the valve or valves
to prevent distortion of the seals from undue high differential
pressure, and the resulting friction.
The present invention, like the prior art, is constructed and
arranged so that the valve or valves remain seated to prevent
communication between the interior of a tubular member and the
interior of an inflatable element carried on the exterior of the
tubular member until at least a predetermined pressure has been
reached. This reduces the possibility of premature inflation of the
inflatable element by sudden pressure changes or pressure surges
which may occur within the tubular member as the tubular member is
being positioned within a well bore.
However, the valve arrangement of the inflation system of the
present invention includes an appropriate arrangement of the valve
structure to compensate for bore pressure to prevent extrusion from
undue high differential pressures across the seals of certain
rubber seals which must move in the valving operation.
.Iadd.In another aspect of the present invention, the valving
arrangement is located at the top of an inflatable packer so that
inflation of the packer can be obtained under adverse pressure
conditions in the borehole.Iaddend..
BRIEF DESCRIPTION OF THE DRAWINGS
For a further understanding of the nature and objects of the
present invention, reference should be had to the following
detailed description, taken in conjunction with the accompanying
drawings, in which like parts are given like reference numerals and
wherein:
FIG. 1 is a cross-section of a packer showing the three-valve
collar for inflation of the packing;
FIG. 2 is an enlarged cross-section of the valve arrangement of
FIG. 1 taken along section line 2--2 of FIG. 1;
FIG. 3 is an enlarged cross-sectional view of the three valves of a
three-valve arrangement within the three-valve collar of the prior
art;
FIG. 4 is an enlarged cross-sectional view of three valves of a
three-valve arrangement of the first embodiment of the present
invention within the three valve collar;
FIG. 5 is a pictoral view of the cross-section of another valve
arrangement of the prior art showing the valve arrangement during
inflation of the packer;
FIG. 6 is a pictoral view of the cross-section of a second
embodiment of the three valves of a three-valve arrangement of the
present invention within the valve collar;
FIG. 7 is an enlarged pictoral view of a cross-section of the three
valves of the three-valve arrangement of FIG. 6 shown inverted to
the normal position of insertion;
FIGS. 8a-c are enlarged pictoral view of the sequence of steps of
inflation of the packer by the three-valve arrangement of FIG. 6
and FIG. 7 shown inverted to the normal position of insertion;
and
FIGS. 9a-c are a pictoral view of the cross-section of a third
embodiment of the valve arrangement of the present invention
showing the valve and the sequence of steps for inflation of the
packer shown inverted to the normal position of insertion.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A tubular .[.member.]. .Iadd.inflatable packer .Iaddend.10 is shown
in FIGS. 1 and 2. This type of .[.member.]. .Iadd.packer
.Iaddend.could be used for any of the embodiments of the present
invention and is specifically illustrated for embodiments 1 and 2,
.[.and may be.]. .Iadd.as .Iaddend.a casing packer. .[.Member.].
.Iadd.The tubular inflatable packer .Iaddend.10 includes a short
casing joint or casing sub 12 for connection to other tubular
members and is secured by suitable means, such as threads as
illustrated in FIG. 1, to a valve collar 14 secured to .[.the
body.]. .Iadd.a tubular pipe member or mandrel .Iaddend.11.[.of the
tubular member 10.].. It should be noted that .Iadd.in one aspect
of the present invention, .Iaddend.the valve collar 14 could also
be and is preferably secured to .[.the.]. .Iadd.a .Iaddend.sub 36
.[.of.]. .Iadd.at the .Iaddend.other end of .[.body.]. .Iadd.the
tubular pipe member .Iaddend.11 shown in .[.FIG. 1.]. .Iadd.FIGS.
6-8.Iaddend.. .[.Valve.]. .Iadd.The valve .Iaddend.collar 14
includes .Iadd.a .Iaddend.valve mechanism 16 .Iadd.or system of
valves and passageways .Iaddend.(.Iadd.See .Iaddend.FIG. 2) for
.[.communicating.]. .Iadd.placing .Iaddend.fluid .[.from the
interior 21 of tubular member 10 to the.]. .Iadd.in a bore or
interior 21 of the pipe member 11 in fluid communication with a
.Iaddend.fluid channel .Iadd.or chamber .Iaddend.20 (.Iadd.See
.Iaddend.FIG. 2) .[.leading to the.]. .Iadd.under an
.Iaddend.inflatable.[., or.]. packing.[.,.]. element .[.22.].
.Iadd.30 .Iaddend.carried externally on .Iadd.the .Iaddend.tubular
.Iadd.pipe .Iaddend.member .[.10.]. .Iadd.11.Iaddend..
The inflatable .Iadd.packing .Iaddend.element .[.22.]. .Iadd.30
.Iaddend.includes spaced apart .Iadd.upper and lower
.Iaddend.annular packer heads 24, 26. .[.Lower.]. .Iadd.The lower
packer .Iaddend.head 26 is secured to .Iadd.the .Iaddend.valve
collar 14.[.. Upper.]. .Iadd.while the upper packer .Iaddend.head
24 is secured to .Iadd.a .Iaddend.top .Iadd.or upper
.Iaddend.collar 35. .[.Inflatable.]. .Iadd.The inflatable packing
.Iaddend.element .[.22.]. .Iadd.30 .Iaddend.extends between
.Iadd.the packer .Iaddend.heads 24, 26 and is also secured to
.[.mandrel 28.]. .Iadd.the pipe member 11 .Iaddend.which extends
along the inside surface of .Iadd.the packing .Iaddend.element
.[.22.]. .Iadd.30 .Iaddend.between .Iadd.the .Iaddend.valve collar
14 .[.to.]. .Iadd.and the .Iaddend.upper collar 35 .[.where mandrel
28 is connected by threading or other means.].. The inflatable
.Iadd.packing .Iaddend.element .Iadd.30 .Iaddend.may be of any
suitable length and is .[.provided with.]. an elastomer cover .[.30
and two.]. .Iadd.with upper and lower .Iaddend.sets of steel
anti-extrusion ribs 32. .[.Ribs.]. .Iadd.The ribs .Iaddend.32 are
connected to the .Iadd.elastomer .Iaddend.cover .[.30,.]. such as,
for example, .[.vulcanized into the rubber, and extend therein.].
.Iadd.by vulcanizing the elastomer cover to the ribs 32 so that the
ribs 32 extend into the ends of the elastomer cover.Iaddend.. Each
set of ribs 32 is connected to a steel back-up sleeve 34, and one
set .Iadd.of ribs .Iaddend.is connected to .Iadd.the .Iaddend.valve
collar 14 while the other set .Iadd.of ribs .Iaddend.is connected
to .Iadd.the upper .Iaddend.collar 35. .[.Sleeve.]. .Iadd.The
back-up sleeve .Iaddend.34 is also connected to .[.packing element
22,.]. .Iadd.the elastomer cover, .Iaddend.such as vulcanized with
the rubber, and to .Iadd.the .Iaddend.valve collar 14. .[.A.].
.Iadd.The tubular .Iaddend.sub 36 is connected to the .[.other
portion of.]. .Iadd.upper .Iaddend.collar 35 for use with other
tubular members .Iadd.in a string of pipe or casing (not
shown).Iaddend..
.[.A.]. .Iadd.As shown in FIG. 2, a .Iaddend.first set of
.Iadd.annular .Iaddend.grooves 38 is formed .[.on.]. .Iadd.in the
.Iaddend.valve collar 14. The set of grooves 38 includes internal,
circumferential or .Iadd.annular .Iaddend.grooves 40, 42 .[.formed
in valve collar 14. Grooves 40, 42 are partially.]. .Iadd.spaced
longitudinally apart from one another and .Iaddend.covered by
.Iadd.a .Iaddend.juxtaposed screen sleeve 44. .[.Sleeve.].
.Iadd.The screen sleeve .Iaddend.44 includes a hole 46 .[.covered
by.]. .Iadd.which receives .Iaddend.a knock-off rod .Iadd.or plug
.Iaddend.50, usually .Iadd.constructed .Iaddend.of plastic, to
isolate the valve system from .Iadd.fluid under .Iaddend.pressure
in the .[.interior.]. .Iadd.bore .Iaddend.21 of the .[.member 10.].
.Iadd.pipe member 11 .Iaddend.during running .Iadd.of the
inflatable packer 10 into a well bore containing
fluid.Iaddend..
.[.Groove 42 terminates in.]. .Iadd.A .Iaddend.port 52
.[.extending.]. .Iadd.extends .Iaddend.partially through the wall
of the valve collar 14 and .[.connecting to.]. .Iadd.connects a
.Iaddend.passageway 54 .Iadd.to the groove 42.Iaddend..
.[.Passageway.]. .Iadd.The passageway 54 extends vertically in the
wall of .Iadd.the .Iaddend.valve collar 14 .[.to.]. .Iadd.between a
port 56 to a valve in the valve mechanism 16 and .Iaddend.the port
.[.56 of the valve system.]. .Iadd.52 .Iaddend.(.Iadd.See FIG.
3).Iaddend..
.[.Embodiment 1.]. .Iadd.PRIOR ART .Iaddend.
.[.Shear.]. .Iadd.In a prior art valve mechanism as shown in FIG.
3, a shear .Iaddend.valve 58 .[.(FIG. 3, FIG. 4).]. is in fluid
communication with .Iadd.the .Iaddend.port 56 .[.via.]..Iadd., the
.[.insertion of.]. .Iadd.shear .Iaddend.valve 58 .Iadd.being
.Iaddend.in .Iadd.a valve .Iaddend.pocket 60 .Iadd.formed by a
cylindrical bore 63 in the wall of the valve collar 14.Iaddend..
.Iadd.The shear valve 58 includes a movable valve element or valve
body 59 slidably disposed in the valve pocket 60. .[.Pocket 60.].
.Iadd.The valve pocket 60 is .Iaddend.formed in .Iadd.the
.Iaddend.valve collar 14 by drilling .[.of.]. .Iadd.or
.Iaddend.other means. .[.Valve.]. .Iadd.One end of the valve
.Iaddend.pocket 60 is in fluid communication with .Iadd.the
.Iaddend.port 56.[.. Pocket 60 forms.]. .Iadd.and this end of the
valve pocket 60 has an .Iaddend.angled valve seat 62 .[.at the end
of pocket 60 in direct fluid communication with.]. .Iadd.disposed
around the .Iaddend.port 56. The .[.other.]. .Iadd.open
.Iaddend.end of .Iadd.the valve .Iaddend.pocket 60 .[.is threaded
with.]. .Iadd.has .Iaddend.threads 61. .[.Pocket 60 is cylindrical
in shape having upper surface 63 of one.]. .Iadd.The movable valve
element 59 has a cylindrical first surface 65a with a first
.Iaddend.diameter .[.in.]. .Iadd.forming an .Iaddend.upper .Iadd.or
first .Iaddend.chamber 65 .Iadd.with the surface wall of the valve
pocket 60 .Iaddend.and .Iadd.has a cylindrical second .[.coaxial.].
surface 67 .[.of.]. .Iadd.with .Iaddend.a second, .[.smaller.].
diameter .[.in.]. .Iadd.forming a .Iaddend.lower .Iadd.or second
.Iaddend.chamber 69 .Iadd.with the surface wall of the valve pocket
60.Iaddend.. .[.Upper.]. .Iadd.The lower or second .Iaddend.chamber
.[.63.]. .Iadd.69 .Iaddend.has an opening to .Iadd.a
.Iaddend.lateral passageway 71 .[.at one end.]. which extends
further into .Iadd.the .Iaddend.valve collar 14.
.[.Valve 58.]. .Iadd.The movable valve element .[.includes a
cylindrical shaped.]. .Iadd.or valve .Iaddend.body 59
.Iadd.defining the cylindrical second surface 67 terminates
.[.with.]. .Iadd.at.Iaddend.an end portion 64 shaped to .[.fit
in.]. .Iadd.compliment the valve .Iaddend.seat 62. A T-seal, or
other suitable seal.[.,.]. 66 is .[.included.]. .Iadd.disposed
.[.along.]. .Iadd.on .Iaddend.the .[.circumference 73 of.].
.Iadd.second surface 67 the valve .Iaddend.body 59 in .Iadd.a
.Iaddend.groove 68 .[.of.]. .Iadd.near the .Iaddend.end portion 64.
.[.Seal.]. .Iadd.The seal .Iaddend.66 is adapted to engage the
.Iadd.surface .Iaddend.wall .[.67 of.]. .Iadd.of the valve pocket
in .Iaddend.the lower .Iadd.or first .Iaddend.chamber 69
.[.substantially parallel to the circumference 73.].. .[.A
threaded.]. .Iadd.The movable valve element or valve body 59 has a
.Iaddend.bore 70 .[.having.]. .Iadd.with .Iaddend.internal threads
74 .[.is formed longitudinally along the lower portion of body 59.
End 64 is connected by.]. .Iadd.to connect to the end portion 64 by
virtue of .Iaddend.external threads 72, or other suitable means.[.,
to internal threads 74 of the longitudinal bore 70.].. The
.Iadd.movable valve element or .Iaddend.valve body 59, as
illustrated, is reduced in size at the end opposite to .Iadd.the
.Iaddend.end portion 64 to form a valve stem 78 with a first
shoulder 80 .[.formed at the juncture of valve stem 78 and.].
.Iadd.on .Iaddend.the valve body 59. A suitable seal 84, such as an
O-ring, is arranged in .Iadd.a .Iaddend.groove 86 on .[.the
upper.]. .Iadd.a .Iaddend.portion of .Iadd.the .Iaddend.valve body
59 between the end portion 64 and .Iadd.the first .Iaddend.shoulder
80. .[.Seal.]. .Iadd.The seal .Iaddend.84 is adapted to seal
against the .[.upper.]. surface .Iadd.wall .Iaddend..[.63 of upper
chamber 65 of pocket 60.]. and .Iadd.the .Iaddend.groove 86
.Iadd.and separate the upper or first chamber 65 from the lower or
second chamber 69.Iaddend..
.[.Valve.]. .Iadd.The valve .Iaddend.stem 78 terminates at .[.its
top.]. .Iadd.an end .Iaddend.88 which .[.is adjacent.]. .Iadd.abuts
an end surface 98 in a sleeve 94 in a .Iaddend.collet 90.
.[.Collet.]. .Iadd.The collet .Iaddend.90 has .Iadd.a
.Iaddend.thick top section 92 and an elongated .Iadd.tubular
.Iaddend.sleeve 94 terminating in bell-shaped.Iadd., .Iaddend.lower
section 96. .[.Sections 92 and 94 form an inner end 98 which abuts
stem top 88. Collet.]. .Iadd.The collet .Iaddend.90, which abuts
.Iadd.the .Iaddend.valve stem 78 at .[.its inner end.]. .Iadd.the
surface .Iaddend.98.[.,.]. is retained in .Iadd.the valve
.Iaddend.pocket 60 by .Iadd.an .Iaddend.annular retainer housing
100 which annularly surrounds .Iadd.the .Iaddend.collet 90
.Iadd.and a shear pin 106 which interconnects the retainer housing
100 to the collet 90.Iaddend.. .[.Annular.]. .Iadd.The annular
.Iaddend.retainer housing 100 has a base 101 with threads 102
.[.formed on the outer circumference thereof. Threads 102.].
.Iadd.which .Iaddend.mate with .Iadd.the .Iaddend.threads 61
.[.which.]. .Iadd.of the valve pocket 60 and .Iaddend..[.secures.].
.Iadd.secure the retainer .Iaddend.housing 100 to .Iadd.the valve
.Iaddend.pocket 60. .[.Housing.]. .Iadd.The retainer housing
.Iaddend.100 further has a bore 97 formed through .Iadd.its
.Iaddend.base 101 to receive .Iadd.the .Iaddend.collet 90 and an
opening 116 .[.at its top.]. through which .Iadd.the top
.Iaddend.section 92 .Iadd.of the collect 90 .Iaddend.extends.
.[.A.]. .Iadd.The .Iaddend.shear pin 106 extends through a bore 99
in .Iadd.a .Iaddend.notch 103 in .[.the.]. .Iadd.an .Iaddend.end
104 of the retainer housing 100 and a bore 105 in the end 92 of
.Iadd.the .Iaddend.collet 90 as shown in FIGS. 3 and 4 to retain
.Iadd.the .Iaddend.valve .[.58.]. .Iadd.body 59 .Iaddend. in the
seated position with .Iadd.its .Iaddend.end portion 64 adjacent
.Iadd.the valve .Iaddend.seat 62 .[.to.]. .Iadd.so that the seal 66
will .Iaddend.block off .[.fluid flow through.]. .Iadd.fluid and
pressure from the .Iaddend.port 56 .[.from.]. .Iadd.and
.Iaddend.the .[.interior 18.]. .Iadd.bore 21 .Iaddend.of the
tubular .Iadd.pipe .Iaddend.member .[.10.]. .Iadd.from access
.Iaddend.to the .Iadd.passageway 71 and hence prevent fluid or
pressure from reaching the .Iaddend.fluid channel 20 leading to the
interior of the inflatable .Iadd.packing .Iaddend.element 30 .[.via
passageway 71.]..
A spring 108 .[.surrounds.]. .Iadd.is disposed on the
.Iaddend.valve stem 78 with one end of the spring abutting the
shoulder 80 and the other end .Iadd.of the spring .Iaddend.abutting
.[.the.]. .Iadd.an .Iaddend.end 110 of the collet 90, such spring
108 being forced to a collapsed position as illustrated when the
valve .Iadd.body 59 .Iaddend.is in the position as shown in
.[.FIGS..]. .Iadd.FIG. .Iaddend.3 .[.and 4.]. of the drawings.
The strength of shear pin 106 will determine the minimum amount of
fluid .[.differential.]. pressure necessary in .Iadd.the
.Iaddend.port 56 to unseat the valve .Iadd.body 59 and to open the
shear valve .Iaddend.58 and .Iadd.to .Iaddend.permit fluid flow
through the port 56 from the .[.interior of tubular.]. .Iadd.bore
21 of pipe .Iaddend.member .[.10.]. .Iadd.11 .Iaddend.to the
interior of .[.packer.]. .Iadd.packing .Iaddend.element 30.
.[.Seals.]. .Iadd.The seals .Iaddend.66, 84 are positioned .Iadd.on
the valve body 59 .Iaddend.such that when the valve .[.58.].
.Iadd.body 59 .Iaddend.is in the seated position as shown in
.[.FIGS. 3 and 4.]. .Iadd.FIG. 3.Iaddend., the seals 66, 84 prevent
any fluid flow .[.from.]. .Iadd.or pressure in the .Iaddend.port 56
.[.to.]. .Iadd.from reaching the .Iaddend.passageway 71. .[.They.].
.Iadd.The seals 66, 84 .Iaddend.also prevent the flow of any fluids
.Iadd.or pressure .Iaddend.from the exterior of .Iadd.the valve
.Iaddend.collar 14 .Iadd.from reaching the passageway 71. Fluid in
.Iaddend..[.in contact with.]. the bore hole .[.which leak.].
.Iadd.leaks .Iaddend..[.through.]. .Iadd.by the .Iaddend.threads
102 and past .Iadd.the .Iaddend.collet 90 in .Iadd.the
.Iaddend.housing 100 .Iadd.and .Iaddend.into .Iadd.the
.Iaddend.upper .Iadd.or first .Iaddend.chamber 65 .[.to flow into
passageway 71.].. In addition, when the valve .[.58.]. .Iadd.body
59 .Iaddend.is in the seated position, .Iadd.the .Iaddend.shoulder
80 .Iadd.on the valve body 59 .Iaddend.is separated from .Iadd.a
.Iaddend.bottom 110 .Iadd.of the collet 90 .Iaddend.by a sufficient
distance .[.such.]. .Iadd.so .Iaddend.that when the valve .[.58.].
.Iadd.body 59 .Iaddend.is no longer in the seated position
.[.but.]. .Iadd.then the .Iaddend.shoulder 80 is as close to
.Iadd.the .Iaddend.shoulder 110 as the .[.springs.]. .Iadd.spring
108 .Iaddend.will allow.[.,.]. .Iadd.and the .Iaddend.seal 66 is
positioned above .Iadd.the .Iaddend.passageway 71 .Iadd.so that
fluid and pressure is admitted to the passageway 71 from the port
56.Iaddend..
In FIG. 3, .Iadd.the check .Iaddend.valves 120 and 122 are
substantially identical in construction. .[.Valves.]. .Iadd.The
check valves .Iaddend.120, 122 are located in .Iadd.valve
.Iaddend.pockets 123, 125 respectively. Each .Iadd.valve
.Iaddend.pocket 123, 125 is .Iadd.formed by a cylindrical bore and
is .Iaddend.substantially cylindrical in shape with walls 124, 126
respectively formed by drilling or other suitable means .[.of.].
.Iadd.and .Iaddend..[.opening with.]. .Iadd.each valve pocket 123,
125 opens at .Iaddend.one end at the exterior outer surface of
.Iadd.the .Iaddend.valve collar 14. The other end of .Iadd.the
valve .Iaddend.pocket 123 terminates at .Iadd.a .Iaddend.portion
127 .Iadd.which places the valve pocket 123 .Iaddend.in fluid
communication with the .[.pocket 123 and.]. passageway 71.
.[.Pocket.]. .Iadd.The valve pocket .Iaddend.123 .[.forms.].
.Iadd.is formed with an .Iaddend.angled valve .[.seats.].
.Iadd.seat .Iaddend.129 at the end of .Iadd.the valve
.Iaddend.pocket 123 in direct fluid communications with .Iadd.the
.Iaddend.port 127. The other end of .Iadd.the valve .Iaddend.pocket
123 is threaded with threads 129'. .[.Passageway.]. .Iadd.A
passageway .Iaddend.131 also .Iadd.is .Iaddend.formed in .Iadd.the
.Iaddend.valve collar 14 .Iadd.and .Iaddend.extends laterally
further into valve collar 14 from the wall of .Iadd.the valve
.Iaddend.pocket 123 and is in fluid communication with .Iadd.the
valve .Iaddend.pocket 123. The other end of .Iadd.the valve
.Iaddend.pocket 125 terminates at .Iadd.a .Iaddend.port 133
.Iadd.which is .Iaddend.in fluid communication with the .Iadd.valve
.Iaddend.pocket 125 and .Iadd.the .Iaddend.passageway 131.
.[.Pocket.]. .Iadd.The valve pocket .Iaddend.125 .[.forms.].
.Iadd.is formed with an .Iaddend.angled valve .[.seats.].
.Iadd.seat .Iaddend.135 at the end of .Iadd.the valve
.Iaddend.pocket 125 .Iadd.and is .Iaddend.in direct fluid
.[.communications.]. .Iadd.communication .Iaddend.with .Iadd.the
.Iaddend. port 133. The other end of .Iadd.the valve
.Iaddend.pocket 125 is threaded with threads 136. .[.Passageway.].
.Iadd.A passageway .Iaddend.137 .Iadd.is .Iaddend.also formed in
.Iadd.the .Iaddend.valve collar 14 .Iadd.and .Iaddend.extends
laterally further into .Iadd.the .Iaddend.valve collar 14 from the
wall .Iadd.126 .Iaddend.of .Iadd.the valve .Iaddend.pocket 125 and
is in fluid communication with .Iadd.the valve .Iaddend.pocket 125
and .Iadd.the .Iaddend.fluid channel 20. .Iadd.(See FIG. 2)
Each of the .[.poppet.]. .Iadd.check .Iaddend.valves 120, 122
includes an end portion 138, 140 respectively of elastomer
.Iadd.material .Iaddend.for engaging on seats 129, 135 respectively
formed between ports 127, 133 and the walls .[.or.]. .Iadd.of the
valve .Iaddend.pockets 123, 125 respectively. Each .Iadd.check
.Iaddend.valve 120, 122 has a .Iadd.movable .Iaddend.valve body
.Iadd.or element .Iaddend.142, 144 respectively. The general shape
of each valve body 142, 144 is cylindrical in configuration. The
.Iadd.valve .Iaddend.body 142, 144 of each valve .Iadd.pocket
.Iaddend.123, 125 has an upper portion 146, 148 respectively and a
lower, smaller diameter portion 150, 152 respectively with a swage
.Iadd.or annular recess .Iaddend.154, 156 respectively separating
the upper and lower portions of .Iadd.a .Iaddend.valve body. The
tops of elastomer .[.ends.]. .Iadd.end portions .Iaddend.138, 140
are fitted into grooves 158, 160 respectively formed
circumferentially in lower .[.ends.]. .Iadd.portions .Iaddend.150,
152 respectively to hold the elastomer .[.ends.]. .Iadd.end
portions .Iaddend.on .Iadd.the .Iaddend.lower portions 150, 152
respectively. A bore 162, 164 is formed .[.through the.]. .Iadd.in
an .Iaddend.end 166, 168 respectively of .Iadd.the
.Iaddend..[.valves.]. .Iadd.valve bodies .Iaddend.142, 144
.[.facing.]. .Iadd.and faces .Iaddend.away from .Iadd.the
.Iaddend.seats 129, 135 and extends substantially through the valve
bodies 142, 144 respectively. A valve stem 170, 171 is inserted in
.[.the.]. .Iadd.a counter .Iaddend.bore 162, 164 respectively with
a spring 174, 176 in its .[.collapsed.]. .Iadd.expanded
.Iaddend.position circumferentially surrounding .Iadd.the valve
.Iaddend.stems 170, 172 respectively.
Each valve stem 170, 172 is received in a bore 178, 180
respectively in .Iadd.a .Iaddend.retainer housing 182, 184 of
.Iadd.the check .Iaddend.valves 120, 122 respectively. Each
retaining housing 182, 184 is externally threaded with threads 186,
188 adapted to mate with threads 129', 136 respectively of
.Iadd.the valve .Iaddend.pockets 123, 125 respectively. Each
.Iadd.retaining .Iaddend.housing 182, 184 also includes .[.a
slot.]. .Iadd.an annular groove .Iaddend.190, 192 sized to receive
a sealing means 194, 196, such as an O-ring, to sealingly engage
the walls 124, 126 of .Iadd.the valve .Iaddend.pockets 123, 125 and
.[.slots.]. .Iadd.the grooves .Iaddend.190, 192 respectively. Each
.Iadd.retaining .Iaddend.housing 182, 184 also includes a
.[.groove.]. .Iadd.slot .Iaddend.198, 199 respectively cut out in
.[.the head.]. .Iadd.each retaining housing .Iaddend.for external
access .Iadd.or removal of valve stems and valve bodies
.Iaddend.from .Iadd. the .Iaddend.valve collar 14.
In operation, when the rod .Iadd.or knock-off plug .Iaddend.50 is
still in place, .Iadd.(See FIG. 2) .Iaddend.any communication of
fluid .Iadd.or pressure .Iaddend.from the .[.interior.]. .Iadd.bore
21 .Iaddend.of tubular .Iadd.pipe .Iaddend.member .[.10.]. .Iadd.11
.Iaddend.to the fluid port 56 .[.of any of the prior art or the
embodiments.]. is prevented. This prevents pressure variations or
pressure surges from acting through port 56 and unseating the valve
.Iadd.body 59 of the shear valve 58 .Iaddend.which might
prematurely inflate the .Iadd.packing .Iaddend.element 30.
When it is desired to actuate the device .[.of any of the
embodiments.]. and communicate fluid to the channel 20 of .Iadd.the
.Iaddend.packing element .[.22.]. .Iadd.30 .Iaddend.carried on the
exterior of the casing or tubular member .[.10.]..Iadd.11.Iaddend.,
any suitable means (not shown) may be dropped through member
.[.10.]. .Iadd.11 .Iaddend.so as to break or shear the rod 50 to
permit fluid communication with the .[.groove set.]. .Iadd.set of
grooves .Iaddend.38.
Thereafter, fluid may be communicated through the .Iadd.set of
.Iaddend.grooves .[.40, 42,.]. .Iadd.38, .Iaddend.the port 52, and
the passage 54 to the inlet port 56 between the inner and outer
walls of the valve collar 14. The fluid pressure of this fluid acts
upon the end portion 64 of the valve .[.58.]..Iadd.body
59.Iaddend., and the pressure within the tubular member .[.10.].
.Iadd.11 .Iaddend.may be increased so as to .Iadd.produce a
pressure differential between the fluid in the bore 21 of the
tubular member 11 and the fluid exterior to the valve collar 14 and
thereby .Iaddend.shear the pin 106 whereupon the valve body 59
moves to a position where .Iadd.the .Iaddend.seal 66 no longer
obstructs the flow of fluid to .Iadd.the .Iaddend.passageway 71
from .Iadd.the .Iaddend.port 56 thereby permitting fluid flow from
.Iadd.the .Iaddend.port 56 through passageway 71 to .Iadd.the
.Iaddend.port 127. This longitudinal movement of .Iadd.the valve
.Iaddend.body 59 causes the valve stem 78 as well as the collet 90
surrounding the end thereof to move outwardly through the opening
116 of the retainer housing 100, compressing .Iadd.the
.Iaddend.spring 108 between the shoulder 80 and the end 110 of the
collet 90. The flow of fluid to .Iadd.the .Iaddend.port 127 builds
.Iadd.up .Iaddend.pressure on .Iadd.the .Iaddend.end 138 .Iadd.of
the valve body 142.Iaddend.. When the pressure on .Iadd.the
.Iaddend.end .Iadd.portion .Iaddend.138 .Iadd.of the valve body 142
.Iaddend.overcomes the break out friction of .Iadd.the .Iaddend.end
.Iadd.portion .Iaddend.138 and the force .Iadd.required .Iaddend.to
compress .Iadd.the .Iaddend.spring 174, .Iadd.the .Iaddend.valve
body 142 .[.rises.]. .Iadd.moves .Iaddend.so that .Iadd.the
.Iaddend.end .Iadd.portion .Iaddend.138 no longer obstructs the
flow of fluid from .Iadd.the .Iaddend.port 127 through .Iadd.the
.Iaddend.passageway 131 to .Iadd.the .Iaddend.port 133. The flow of
fluid to .Iadd.the .Iaddend.port 133.Iadd., in turn,
.Iaddend.builds .Iadd.up .Iaddend.pressure on .Iadd.the
.Iaddend.end .Iadd.portion .Iaddend.140.[.,.]. .Iadd.of the valve
body 144. .Iaddend..[.when.]. .Iadd.When .Iaddend.the pressure on
.Iadd.the .Iaddend.end .Iadd.portion .Iaddend.140 overcomes the
break out friction of .Iadd.the .Iaddend.end .Iadd.portion
.Iaddend.140 and the force .Iadd.required .Iaddend.to compress
.Iadd.the .Iaddend.spring 176, .Iadd.the .Iaddend.valve body 144
.[.rises.]. .Iadd.moves .Iaddend.so that .Iadd.the .Iaddend.end
.Iadd.portion .Iaddend.140 no longer obstructs the flow of fluid
from .Iadd.the .Iaddend.port 133 to .Iadd.the .Iaddend.passageway
137 to .Iadd.the .Iaddend.channel 20 and .[.packer.]. .Iadd.fluid
supplied to the packing element .Iaddend.30 inflates .Iadd.the
packing element 30.Iaddend..
Those skilled in the art would believe that .Iadd.the
.Iaddend.shear pin 106 .Iadd.in the shear valve 58 .Iaddend.would
shear at a given pressure at .Iadd.the .Iaddend.port 56
.Iadd.relative to the pressure exterior of the valve collar 14
.Iaddend.depending only on the strength of the shear pin 106.
However, this is not the case. At the time the tubular .Iadd.pipe
.Iaddend.member .[.10.]. .Iadd.11 .Iaddend.is lowered into the
well, the pressure in .Iadd.the .Iaddend.passageway 71 is at
atmospheric pressure. The same is true of the pressures in
.Iadd.the .Iaddend.upper .[.pocket.]. .Iadd.or first
.Iaddend.chamber 65 and the pressure at .Iadd.the .Iaddend.port 56.
However, as the tubular .Iadd.pipe .Iaddend.member .[.10.].
.Iadd.11 .Iaddend.is lowered into the well, the pressure in
.Iadd.the .Iaddend.upper .[.pocket.]. .Iadd.or first
.Iaddend.chamber 65 changes to .[.that of the exterior of.].
.Iadd.the pressure in .Iaddend.the well because there is no seal
.[.through.]. .Iadd.to prevent well fluid from leaking by the
.Iaddend.retainer housing 100 as discussed above. In addition, as
pressure within the tubular .Iadd.pipe .Iaddend.member .[.10.].
.Iadd.11 .Iaddend.increases, the pressure at .Iadd.the
.Iaddend.valve port 56 increases. However, there is no path for the
rising .Iadd.or increasing fluid .Iaddend.pressure to enter
passageway 71 and .Iadd.to .Iaddend.raise .[.it.]. .Iadd.the
pressure in passageway 71 .Iaddend.above atmospheric
.Iadd.pressure.Iaddend.. Accordingly, while the valve .Iadd.body 59
.Iaddend.is seated, .Iadd.the .Iaddend.seals 66, 84 will tend to
extrude toward .Iadd.the .Iaddend.passageway 71 because of the high
differential pressure between the upper .[.pocket.]. .Iadd.or first
.Iaddend.chamber 65 and .Iadd.the .Iaddend.passageway 71, and
.Iadd.the high differential pressure .Iaddend.between .Iadd.the
.Iaddend.lower .[.pocket.]. .Iadd.or second .Iaddend.chamber 69 and
.Iadd.the .Iaddend.passageway 71. In such circumstance, the
.[.seal.]. .Iadd.seals .Iaddend..[.rings.]. 66, 84 .[.are.].
.Iadd.become .Iaddend.locked and the pressure .Iadd.required in the
port 56 .Iaddend.to overcome .Iadd.the .Iaddend.breakout friction
to move .Iadd.the valve .Iaddend.body 59 .[.then goes.]. .Iadd.is
.Iaddend.much higher. This is because the O-rings usually used in
the prior art .[.of.]. .Iadd.embodiment shown in .Iaddend.FIG. 3
are designed to only hold 4,000 to 5,000 psi of differential
pressure. In deep wells, this breakout friction would be very high
and normally a discontinuity in breakout .[.pressure.].
.Iadd.friction .Iaddend.is exhibited at wells having a depth which
exhibit downhole pressures of 5,000 to 6,000 psi. In addition,
.[.as discussed above, the diameter.]. .Iadd.the annulus
.Iaddend.of .Iadd.the .Iaddend.upper .[.pocket.]. chamber 65 is
larger than .Iadd.the annulus of the .Iaddend.lower .[.pocket.].
chamber 69. In the prior art, in order to overcome this difference
in .[.diameter.]. .Iadd.the annulus.Iaddend., a sleeve is installed
in .Iadd.the .Iaddend.upper .[.pocket.]. chamber 65. Nevertheless
the .[.sleeves.]. .Iadd.sleeve .Iaddend.may not be perfect and the
remaining space in the upper .[.pocket.]. chamber 65 is elliptical
in shape having a major and a minor diameter both larger than the
diameter of .Iadd.the .Iaddend.lower .[.pocket.]. chamber 69.
Therefore, the force of the pressure on .Iadd.the .Iaddend.seal 84
in .Iadd.the .Iaddend.upper .[.pocket.]. chamber 65 is greater than
the force by an identical pressure acting on .Iadd.the
.Iaddend.seal 66 from .Iadd.the .Iaddend.valve port 56.
Accordingly, as the well .[.is deeper and.]. .Iadd.depth increases,
.Iaddend.the pressure in upper .[.pocket.]. chamber 65
increases.[.,.]. .Iadd.and .Iaddend.the amount of pressure required
at .Iadd.the .Iaddend.port 56 .Iadd.to open the valve 58
.Iaddend.may be far greater than anticipated .[.by knowledge of.].
.Iadd.with respect to .Iaddend.the shear strength .Iadd.required
.Iaddend.of shear pin 106 in order to cause shear pin 106 to shear
.Iadd.at a selected pressure.Iaddend..
.Iadd.1ST EMBODIMENT .Iaddend.
To avoid the problems of the prior art .[.of.]. .Iadd.embodiment
illustrated in .Iaddend.FIG. 3.Iadd., .Iaddend.the .Iadd.present
invention utilizes a .Iaddend.valve system .[.is modified.]. as
shown in FIG. 4. .[.The modifications include removal of shear
valve 58 from pocket 60. In addition,.]. .Iadd.In FIG. 4 as
compared to FIG. 3, the check .Iaddend.valve 120 is .[.also.].
removed .Iadd.from the valve pocket 123.Iaddend.. .[.After.].
.Iadd.When the .Iaddend.shear valve 58 is removed from .Iadd.the
valve .Iaddend.pocket 60.[.. All.]. .Iadd.all .Iaddend.grease is
removed from .Iadd.the .Iaddend.O-ring .Iadd.seal .Iaddend.84 and
.Iadd.the .Iaddend.T-seal ring 66. The shear valve .Iadd.58
.Iaddend.is then lubricated with Baker Tubing Seal Grease Number
499-26 which is not reactant with the O-ring seal 84 or the T-seal
66 at elevated temperatures.[.. The shear valve 58 is.]. .Iadd.and
.Iaddend.then replaced in .Iadd.the valve .Iaddend.pocket 60 in the
manner known in the prior art. .[.Pocket.]. .Iadd.The valve pocket
.Iaddend.123 is then filled, preferably with water or other
suitable substance, although it could be left unfilled. .Iadd.The
shear valve 58 thus has a reciprocating valve element or valve body
member 59 with seals 66 and 84 which prevent flow of fluid to the
passage 71 (part of the passageway means) and stop means in the
form of the shear pin 106 which prevent reciprocation of the
reciprocating valve member prior to the application of a
predetermined pressure difference. .Iaddend.
.[.A modified.]. .Iadd.As shown in FIG. 4, a .Iaddend.retainer
housing 182' is .[.then.]. installed in .Iadd.the valve
.Iaddend.pocket 123. The .[.modified.]. retainer housing 182'
includes a bore 200 of smaller diameter than .Iadd.the
.Iaddend.bore 178.[.drilled coaxially through bore 178.
Housing.]..Iadd.. The housing .Iaddend.182' .[.is.]. further
.[.modified to include.]. .Iadd.includes a .Iaddend.counter bore
202 coaxial with and of smaller diameter than .Iadd.the
.Iaddend.bore 200 .Iadd.and is .Iaddend.formed by drilling or other
means through the approximate center of .Iadd.a transverse
.Iaddend.groove 198. The disparity of diameters causes .Iadd.an
.Iaddend.downwardly, outwardly sloping shoulder 204 to be formed
between .Iadd.the .Iaddend.bore 178 and .Iadd.the .Iaddend.bore 200
and .Iadd.an .Iaddend.downwardly, outwardly sloping shoulder 206 to
be formed between .Iadd.the .Iaddend.bore 200 and .Iadd.the
.Iaddend.bore 202. A ball 208 is located within .Iadd.the retainer
.Iaddend.housing 182' in close proximity to the opening of
.Iadd.the .Iaddend.bore 202 facing .Iadd.the .Iaddend.bore 200.
.[.Ball.]. .Iadd.The ball .Iaddend.208 is held against .Iadd.the
.Iaddend.shoulder 206 by .Iadd.a .Iaddend.compressed spring 212.
.[.Spring.]. .Iadd.The spring .Iaddend.212 is compressed by .Iadd.a
.Iaddend.rod 210 which contains an internal longitudinal fluid
passageway 211 extending therethrough and opening at each end.
.[.Rod.]. .Iadd.The rod .Iaddend.210 is inserted into .Iadd.the
.Iaddend.bore 178 by hammering or other means to force the rod 210
into the entry of .Iadd.the .Iaddend.bore 200 where it is held by
friction with .Iadd.the .Iaddend.spring 212 and .Iadd.the
.Iaddend.ball 208 extending into .Iadd.the .Iaddend.cocurrent bore
200 such that .Iadd.the .Iaddend.ball 208 abuts the shoulder 206
and the rod 210 extends substantially into the shoulder 204 forming
a check valve assembly 214.
.Iadd.The flow passage or port 56 is independent of the seals 84
and 66 for permitting flow of fluid from the interior or bore of
the pipe member 11 to one side of the seal 66 and the retainer
housing 100 is independent of the seals 84 and 66 for permitting
the flow of fluid from the exterior of the valve collar 14 and the
pipe member 11 to an oppositely facing surface of the seal 84.
The structure in the valve pocket 123 comprises means independent
of the seals 84 and 66 for permitting the flow of fluid via passage
71 at the pressure exterior to the pipe member 11 and the valve
collar 14 to the other side of each of the seals to equalize the
pressure across the seals 66 and 84. .Iaddend.
In operation, .Iadd.when the valve system of FIG. 4 is installed in
.Iaddend.the .[.member 10 of the first embodiment of FIG. 4,
when.]. .Iadd.valve collar 14 and .Iaddend.lowered into the bore
hole, .[.will cause.]. the pressure in .Iadd.the
.Iaddend.passageway 71 .[.to.]. .Iadd.will .Iaddend.be
approximately the same as the pressure in .Iadd.the .Iaddend.upper
.[.pocket.]. chamber 65 of .[.bore.]. .Iadd.the valve pocket
.Iaddend.60. This is effected by the check valve assembly 214
.Iadd.in the valve pocket 123.Iaddend.. As pressure from the bore
hole acts on .Iadd.the .Iaddend.tubular .Iadd.pipe .Iaddend.member
.[.10.]. .Iadd.11.Iaddend., and particularly on .[.modified.].
.Iadd.the retainer .Iaddend.housing 182', fluid will flow from
.Iadd.the .Iaddend.counter bore 202 through .Iadd.the .Iaddend.bore
200 to .Iadd.the .Iaddend.bore 178, around .Iadd.the .Iaddend.ball
208, through .Iadd.the .Iaddend.passageway 211 in .Iadd.the
.Iaddend.hollow rod 210 and thence to .Iadd.the valve
.Iaddend.pocket 123, .Iadd.the .Iaddend.port 127 and .Iadd.the
.Iaddend.passageway 71. This will permit the fluid in .Iadd.the
valve .Iaddend.pocket 123 to be maintained at the pressure
approximately that surrounding the tubular .Iadd.pipe
.Iaddend.member .[.10.]. .Iadd.11 .Iaddend.which is substantially
the pressure in the upper .[.pocket.]. chamber 65. Accordingly, the
differential pressure between .Iadd.the .Iaddend.upper .[.pocket.].
chamber 65 .Iadd.in the valve pocket 60 .Iaddend.and .Iadd.the
pressure in the .Iaddend.passageway 71 across .Iadd.the
.Iaddend.seal 84 will be very small. Further, the pressure at
.Iadd.the .Iaddend.port 56 will also initially be approximately
that of the .Iadd.well .Iaddend.bore so that the differential
pressure across .Iadd.the .Iaddend.seal 66 will be very small. In
addition, as the pressure in port 56 .[.increases, and.]. .Iadd.is
increased to shear the .Iaddend.pin 106 .[.shears, causing.].
.Iadd.and cause the valve .Iaddend.body 59 to move .[.such
that.]..Iadd., the .Iaddend.seal 66 moves to a position
longitudinally above passageway 71.[.,.]. .Iadd.and .Iaddend.the
pressure in .Iadd.the valve .Iaddend.pocket 123 will increase
causing .Iadd.the .Iaddend.ball 208 to seat on the shoulder 206
thereby stopping further fluid communication between .Iadd.the
.Iaddend.bore 200 and .Iadd.the .Iaddend.bore 202. Therefore, the
pressure in passageway 71 .[.will.]. .Iadd.can .Iaddend.continue to
rise .Iadd.or increase .Iaddend.causing .Iadd.the check
.Iaddend.valve 122 to unseat and permitting fluid flow to .Iadd.the
.Iaddend.passageway 137.
The .[.modified port plug.]. .Iadd.retainer housing .Iaddend.182'
is usually covered with Shell Darina Grease Number 2 or other
suitable lubricant to prevent plugging of the check valve 214.
In addition, because multiple packers are usually run along a
tubular string comprised of tubular .Iadd.pipe .Iaddend.members
.[.10.]. .Iadd.11 .Iaddend.and other tubular members, the seal
diameters should be measured and an indication of such be made,
such as on the valve collar 14. In this manner the packer with the
smallest upper seal 84 area will be run closest to the bottom of
the hole to minimize distortion caused by different areas between
.Iadd.the .Iaddend.seals 84 and 66 since the devices of the prior
art always have a larger area for .Iadd.the .Iaddend.seal 84 than
for .Iadd.the .Iaddend.seal 66.
.[.Embodiment 2.]. .Iadd.PRIOR ART .Iaddend.
Referring to FIG. 5, a different .Iadd.prior art .Iaddend.valve
configuration for use with a tubular .Iadd.pipe .Iaddend.member
.[.10.]. .Iadd.11 and inflatable casing packer where the packer
element 30 .Iaddend.is shown in .[.the.]. .Iadd.an
.Iaddend.inflated and locked position. Except for the valve collar,
the rest of the elements of .[.tubular member.]. .Iadd.inflatable
packer .Iaddend.10 are substantially identical and like reference
numerals will be used in reference to same. As shown in FIG. 5,
.Iadd.a .Iaddend.valve collar 14' includes three valves 58, 120,
224.
.[.In embodiment 2,.]. .Iadd.In the device shown in FIG. 5,
.Iaddend.after the rod 50 is displaced, fluid again flows through
.Iadd.a .Iaddend.passageway .[.54,.]. and optionally a screen 226,
and enters .Iadd.a .Iaddend.port 56 which is .Iadd.initially
.Iaddend.sealed by a .Iadd.shear .Iaddend.valve 58. The problem of
extrusion of .Iadd.the .Iaddend.seals 66 and 84 when the
.Iadd.shear .Iaddend.valve .Iadd.58 .Iaddend.is initially lowered
into the well is still a problem in the prior art of FIG. 5 except
that a .Iadd.valve .Iaddend.pocket .[.60'.]. .Iadd.60 .Iaddend.is
used .[.with.]. .Iadd.where .Iaddend.the diameter of .Iadd.an
.Iaddend.upper pocket chamber .[.65'.]. .Iadd.65 .Iaddend.is
substantially identical to the diameter at .Iadd.a .Iaddend.lower
pocket chamber 69. The problem results from the pressure in
.Iadd.the .Iaddend.passageway 71 being substantially at atmospheric
pressure when the valve collar .[.14.]. .Iadd.14' .Iaddend.is
lowered into the bore because .Iadd.the .Iaddend.seal 138 .Iadd.on
the check valve 120 normally .Iaddend.prevents any flow to
passageway 71 from the .[.packer channel 20.]. .Iadd.passageway 137
.Iaddend.and .Iadd.the .Iaddend.seals 66, 84 prevent any leakage
from chambers .[.65'.]. .Iadd.65.Iaddend., 69 to .Iadd.the
.Iaddend.passageway 71. Accordingly, the prior art arrangement as
set out in FIG. 5 fails to prevent the extrusion of the seals 66,
84 and, accordingly, does not have a predictable shear valve
pressure for the same reasons as set out in the description of
.Iadd.the prior art valve in .Iaddend.FIG. 3.
.Iadd.Embodiment 2 .Iaddend.
As shown in FIG. 6, the present invention utilizes .[.the same
valves 58, 120.]. .Iadd.a shear valve 58 and a check valve 120
.Iaddend.as the prior art of FIG. 5 .Iadd.and all of the valves are
located in a valve collar 14 at the upper end of a packer.Iaddend..
.[.However,.]. .Iadd.In FIG. 6, however, the shear .Iaddend.valve
58 and .Iadd.the check .Iaddend.valve 120 are interchanged .[.in
pockets 60', 123..]. .Iadd.so that the shear valve 58 is in the
middle valve pocket 123 and the check valve 120 is in the first
valve pocket 60. .Iaddend.In addition, a third valve .[.228.].
.Iadd.224 .Iaddend.is used .Iadd.in a valve pocket 230
.Iaddend.which is substantially different from .Iadd.the
.Iaddend.valve 122 .Iadd.shown in FIG. 3 in the valve pocket 125
.Iaddend.and is, preferably, identical to prior art valve 224
.[.supplied.]. .Iadd.shown in FIG. 5 and is used .Iaddend.by Lynes,
Inc. in its External Casing Packer. As seen in .[.FIG. 7.].
.Iadd.FIGS. 5-7.Iaddend., .Iadd.the third .Iaddend.valve .[.228.].
.Iadd.224 .Iaddend.is located in .Iadd.the valve .Iaddend.pocket
230.
.[.Valve 228.]. .Iadd.The valve 224 in the valve pocket 230 and
illustrated in FIG. 7, is a pressure limit valve which
.Iaddend.includes .[.split.]. .Iadd.separated .Iaddend.valve
bodies, .Iadd.i.e., an .Iaddend.upper valve body .Iadd.or member
.Iaddend.254 and .Iadd.a .Iaddend.lower valve body .Iadd.or member
.Iaddend.256.[., in.]. .Iadd.which are disposed in the valve
.Iaddend.pocket 230. .[.Pocket.]. .Iadd.The valve pocket
.Iaddend.230 is substantially longer than .Iadd.the valve
.Iaddend.pocket 125 .Iadd.(FIG. 3, FIG. 4).Iaddend., such extension
being formed by a longer bore .[.extension.]. .Iadd.252 extending
.Iaddend.into .Iadd.the .Iaddend.valve collar 14' (the prime is
used to denote a different collar 14 with substantially the same
pocket and passageway configuration except as otherwise described
in the description of this Embodiment 2).[., forming a substantial
pocket chamber.]. .Iadd.. The bore .Iaddend.252 .Iadd.extends the
valve pocket 230 .Iaddend.beyond passageway 131 and
.[.eliminating.]. .Iadd.thus eliminates the .Iaddend.port 133
.Iadd.(FIG. 3).Iaddend.. .[.Valve chamber.]. .Iadd.The bore
.Iaddend.252 is in fluid communication with .[.the rest of the
valve pocket 230, including with.]. .Iadd.the .Iaddend.passageways
131, 137. .[.Pocket chamber.]. .Iadd.The bore .Iaddend.252 .[.is.].
.Iadd.has a .Iaddend.cylindrical .[.in shape with walls.].
.Iadd.wall .Iaddend.231 and .[.forms.]. .Iadd.has an
.Iaddend.angled valve seat 232 at .[.the.]. .Iadd.one .Iaddend.end
.[.of chamber 252.]. in direct fluid communication with .Iadd.a
.Iaddend.port 234 leading to a passageway 236 which is a return
.Iadd.passage .Iaddend.from the interior of .[.packer.]. .Iadd.the
packing element .Iaddend.30. The other end of .Iadd.the valve
.Iaddend.pocket 230 is threaded with threads 238.
.[.Lower.]. .Iadd.A lower .Iaddend.valve body 256 includes an end
portion 258 shaped to .[.fit in.]. .Iadd.compliment the valve
.Iaddend.seat 232. First and second seals 260, 262 .Iadd.in the
valve body 256 .Iaddend.are adapted to engage the wall 231 of the
.[.lower chamber.]. .Iadd.bore .Iaddend.252 of .Iadd.the valve
.Iaddend.pocket 230. .[.End.]. .Iadd.The end portion .Iaddend.258
may be a separate piece and connected by external threads or other
suitable means to internal threads of a longitudinal bore in the
rest of the .Iadd.lower valve .Iaddend.body 256. The valve body
256, as illustrated, is cylindrical in configuration and is reduced
in size .[.at the end opposite to end portion 258 to form a short
valve stem 264.]. .Iadd.intermediate of the upper valve body 254
and the lower valve body 256.Iaddend.. In addition, a relief bore
265 is drilled in .Iadd.the valve .Iaddend. body 256 between
.Iadd.the .Iaddend.seals 260, 262 and .Iadd.is .Iaddend.in fluid
communication with .[.chamber.]. .Iadd.the bore .Iaddend.252 there
between .Iadd.and .Iaddend.through .Iadd.the .Iaddend.end portion
258 .[.and.]. .Iadd.is .Iaddend.in fluid communication with
.Iadd.the .Iaddend.port 234.
.[.Valve.]. .Iadd.The valve .Iaddend.stem 264 terminates at
.Iadd.the .Iaddend.upper body member 254. .[.Member.]. .Iadd.The
upper body member .Iaddend.254 also has a seal 266 .[.disposed
about member 254 and.]. adapted to seal against .Iadd.the
.Iaddend.wall 231. .[.Upper.]. .Iadd.The upper .Iaddend.valve body
.Iadd.member .Iaddend.254, as illustrated, is cylindrical in
configuration and is reduced in size at the end opposite .Iadd.to
the valve .Iaddend.stem 264 to form .[.a.]. .Iadd.another
.Iaddend.valve stem 268 .[.forming.]. .Iadd.and forms .Iaddend.a
shoulder 267 therebetween. .[.Valve.]. .Iadd.The valve
.Iaddend.stem 268 extends through a bore 269 in a retainer housing
270 at the end of .Iadd.the valve .Iaddend.pocket 230 opposite
.Iadd.to the valve .Iaddend.seat 232. This end .Iadd.of the valve
pocket 230 .Iaddend.is an open portion of the external surface of
.Iadd.the .Iaddend.valve collar 14'. .[.Annular.]. .Iadd.The
.Iaddend.retainer housing 270 .Iadd.is annular and .Iaddend.has a
base 272 with threads 274 formed on the outer circumference
thereof. .[.Threads.]. .Iadd.The threads .Iaddend.274 match with
threads 238 .[.which secures.]. .Iadd.and secure the retainer
.Iaddend.housing 270 to .Iadd.the valve .Iaddend.pocket 230.
.[.Housing.]. .Iadd.The retainer housing .Iaddend.270 further has a
wing extension 275 in .Iadd.an .Iaddend.end 276 .Iadd.of the
retainer housing 270 .Iaddend.to control the length of extension of
.[.valve 228.]. .Iadd.the valve body members .Iaddend.into
.Iadd.the valve .Iaddend.pocket 230.
A shear pin 277 extends through a bore 278 in a notch 280 in the
end 276 of the retainer housing 270 and a bore 282 in the end of
the .Iadd.valve .Iaddend.stem 268 adjacent .Iadd.to the
.Iaddend.bore 269 as shown in FIG. 7 to retain .Iadd.the
.Iaddend.valve .[.228.]. .Iadd.stem 268 and valve body members
.Iaddend.in the seated position adjacent .Iadd.to the .Iaddend.seat
232 to block off fluid flow from or to .Iadd.the .Iaddend.port 234
and .Iadd.to .Iaddend.permit the flow of fluid from .Iadd.the
.Iaddend.passageway 131 to .Iadd.the .Iaddend.passageway 137. The
.Iadd.shear .Iaddend.strength of .Iadd.the .Iaddend.shear pin 277
will determine the amount of fluid pressure necessary in .Iadd.the
.Iaddend.port 234 to unseat the valve .[.228.]. .Iadd.body member
256 .Iaddend.and block the flow through the .Iadd.the
.Iaddend.passageway 131 to passageway 137. In this regard,
.Iadd.the .Iaddend.seals 260, 262 are located on .Iadd.the valve
.Iaddend.body members 256 and .Iadd.254 and are .Iaddend.spaced far
enough apart from each other so that as .Iadd.the .Iaddend.end 267
.Iadd.of the valve body member 254 .Iaddend.abuts the bottom of
.Iadd.a .Iaddend.base 272 .Iadd.of the retainer housing 270
.Iaddend.as pressure in port 234 urges .Iadd.the .Iaddend.end
.Iadd.portion .Iaddend.258 away from .Iadd.the .Iaddend.seat 232,
.Iadd.the .Iaddend.seals 260, 262 will straddle .Iadd.the
.Iaddend.passageway 131 (FIG. 8c).
As shown in FIGS. 8a and 8b, in operation the invention of FIG. 6
.Iadd.and FIG. 7 .Iaddend.is activated initially by pressure of
fluid in .Iadd.the .Iaddend.port 56 from the .[.internal portion.].
.Iadd.bore .Iaddend.of tubular .Iadd.pipe .Iaddend.member .[.10.].
.Iadd.11 .Iaddend.acting on .Iadd.the .Iaddend.end .Iadd.portion
.Iaddend.138 of .Iadd.the check .Iaddend.valve 120 after .Iadd.the
.Iaddend.rod 50 is removed. Only sufficient pressure is needed to
overcome .[.the.]. .Iadd.a .Iaddend.spring 174 and raise .Iadd.or
move the .Iaddend.end .[.120.]. .Iadd.portion 138 .Iaddend.above
.Iadd.the .Iaddend.passageway 71 .Iadd.so that fluid can flow to
the shear valve 58.Iaddend.. Therefore, .[.the.]. atmospheric
pressure trapped in .Iadd.the .Iaddend.passageway 71 will be
relieved and no adverse effect would be had on the seals 66, 84
.Iadd.or the seals 260, 262 and 266. When the pressure in
passageway 71 exceeds the retaining force of the shear pin in shear
valve 58, the shear valve 58 opens passageway 131.Iaddend.. In this
regard, it should be noted that before an inflatable .Iadd.packing
.Iaddend.element 30 is permitted to be lowered into a well hole,
some fluid is flushed through it to make sure no air pockets exist
in the assembly to prevent failure, for example, by support rubber
between the .[.casing 10.]. .Iadd.tubular pipe member 11
.Iaddend.and the .[.end assembly.]. .Iadd.sleeve 34 (see FIG. 2)
.Iaddend.or extrusion of the rubber into the fluid channel 20 when
the tubular .Iadd.pipe .Iaddend.member .[.10.]. .Iadd.11
.Iaddend.is initially lowered into the well. Accordingly, as seen
in FIG. 8a, the well pressure will act on this trapped fluid
through .[.packer.]. .Iadd.the packing element .Iaddend.30 thereby
causing .[.it.]. .Iadd.the trapped fluid .Iaddend.to flow through
.Iadd.the .Iaddend.channel 20, .Iadd.the .Iaddend.passageway 137,
.Iadd.the valve .Iaddend.pocket 230 and .Iadd.the
.Iaddend.passageway 131 and the pressure therethrough .[.to.].
.Iadd.will .Iaddend.be approximately equal to the well pressure.
.Iadd.It is noted that the pressure in passageways 137 and 236 is
equal and does not affect the valve body member 256. The pressure
through fluid leakage about the valve stem 268 is also equal to the
well pressure. .Iaddend.
.[.When.]. .Iadd.Thus when .Iaddend.the pressure in .Iadd.the
.Iaddend.passageway 71 exceeds the pressure necessary to shear
.Iadd.the shear .Iaddend.pin .[.106.]. .Iadd.in the shear valve 58
.Iaddend.(not shown .Iadd.in detail .Iaddend.in FIGS. 6-8), the
shear pin .[.106.]. will shear and .Iadd.the .Iaddend.seal 66
.Iadd.of the shear valve 58 .Iaddend.will rise above passageway
.[.13.]. .Iadd.131 .Iaddend.as shown in FIG. 8b in the manner set
out above. Fluid will then flow through .Iadd.the
.Iaddend.passageway 131, around .Iadd.the valve .Iaddend.stem 264
of .Iadd.the .Iaddend.valve .[.224.]. .Iadd.body members 256 and
254 .Iaddend.and thence through .Iadd.the .Iaddend.passageway 137
into .Iadd.the .Iaddend.channel 20 .Iadd.(see FIG. 2) .Iaddend.for
inflation of the .[.packer.]. .Iadd.packing element .Iaddend.30.
Fluid returning to .Iadd.the .Iaddend.passageway 236 and .Iadd.the
.Iaddend.port 234 from .[.packer.]. .Iadd.the packing element
.Iaddend.30 will build .Iadd.or increase in .Iaddend.pressure as
the .[.packer 30 inflates.]. .Iadd.packing element 30 is inflated
.Iaddend.until the .Iadd.differential .Iaddend.pressure between
.Iadd.the .Iaddend.port 234 and the .Iadd.pressure exterior to the
.Iaddend.valve pocket 230 exceeds the .Iadd.shear .Iaddend.capacity
of shear pin 277 .Iadd.in the valve 224 .Iaddend.(FIG.
.[.6.]..Iadd.7.Iaddend.). As shown in FIG. 8c, when this occurs,
.Iadd.the .Iaddend.shear pin 277 will shear and .Iadd.the
.Iaddend.lower .Iadd.valve .Iaddend.body .[.section.]. 256 will be
moved into position adjacent .Iadd.to the .Iaddend.passageway 131
with .[.end.]. .Iadd.the shoulder portion .Iaddend.267 abutting the
bottom of .Iadd.the retainer housing 270. In that position
.Iadd.the .Iaddend.seals .[.60, 84.]. .Iadd.260, 262 .Iaddend.will
straddle .Iadd.the .Iaddend.passageway 131 preventing further flow
from .Iadd.the .Iaddend.passageway 131 to .Iadd.the
.Iaddend.passageway 137 thereby locking the .[.packer.].
.Iadd.pressure in the packing element .Iaddend.30 in the inflated
position. In this regard, .Iadd.the .Iaddend.bore 265 is provided
for fluid communication for the .[.chamber.]. .Iadd.portion of the
bore .Iaddend.252 .[.portion.]. between .Iadd.the .Iaddend.seals
260 and 262 to .[.bore.]. .Iadd.the port .Iaddend.234 and .Iadd.the
.Iaddend.passageway 237 so that atmospheric pressure captured
between these two seals 260, 262 will be vented to prevent
possibility of extrusion of .Iadd.the .Iaddend.seals 260 and 262
from .Iadd.the .Iaddend.differential pressure either as a result of
pressure in .[.chamber 256.]. .Iadd.the bore 252 .Iaddend.or in
.Iadd.the .Iaddend.passageway 236. Alternatively, the portion of
the lower .[.chamber.]. .Iadd.bore .Iaddend.252 opposite .Iadd.to
the .Iaddend.seal 260 when .Iadd.the .Iaddend.seal 260 is in its
lower most position may be slightly enlarged or grooved to permit
fluid communication between .Iadd.the .Iaddend.seals 260, 262 and
.Iadd.the .Iaddend.passageway 236. Such enlargement or groove would
be spaced such that .Iadd.the .Iaddend.seal 260 would rise above
the enlargement or groove in its uppermost position and seal
against the wall of .Iadd.the .Iaddend.lower .[.chamber.].
.Iadd.bore .Iaddend.252.
It all embodiments .Iadd.of FIG. 6-8.Iaddend., it should be noted
that the valve collar .Iadd.14' .Iaddend.is located at the upper
end of the tubular .Iadd.pipe .Iaddend.member .[.10.]. .Iadd.11
.Iaddend.instead of the lower end. In this manner, .Iadd.the
.Iaddend.pressure .Iadd.in the well bore .Iaddend.cannot be trapped
between, for example, the well bottom and the .[.packer.].
.Iadd.inflated packing element .Iaddend.30 which would have an
effect on the differential pressure across the valves thereby
preventing the valve 224 from closing. .Iadd.In other words, if the
valve system of FIGS. 6-8 is located at the bottom of the packer,
when the packer inflates, the pressure on the exterior of the pipe
member 11 below the packer may be higher or lower than the
hydrostatic pressure above the packer. With the valve 224 above the
packer the hydrostatic pressure above the packer will always be
less than the internal pressure in the packer element 30 and will
always operate. .Iaddend.
Embodiment 3
Referring to FIG. 9a, there is .Iadd.diagramatically .Iaddend.shown
a third embodiment .[.of the.]. .Iadd.which utilizes a single
.Iaddend.inflation control valve in a single .Iadd.valve
.Iaddend.pocket 300. .[.The.]. .Iadd.A valve .Iaddend.pocket 300 is
bored into a valve collar 14" (the double prime is used to denote a
different collar than collar 14 or 14' with substantially the same
pocket and passageway configuration, .Iadd.between the interior or
bore of the pipe member 11, the exterior of the valve body and the
channel 20 to the interior of the packing element 30,
.Iaddend.except having one .Iadd.valve .Iaddend.pocket and except
as otherwise described in the description of this embodiment 3) or
formed in a sleeve or other suitable location. .[.Bore.]. .Iadd.A
bore .Iaddend.301, .Iadd.a .Iaddend.first counterbore 302 and
.Iadd.a .Iaddend.second counterbore 304.[., counterbores.].
.Iadd.are the single valve pocket 300. Counterbores
.Iaddend.302.[.,.]. .Iadd.and .Iaddend.304 .Iadd.are
.Iaddend.separated by stop wings 306, .Iadd.and the counterbores
.Iaddend.are formed by drilling or other suitable operation in
.Iadd.the .Iaddend.pocket 300. .[.Stop.]. .Iadd.The stop
.Iaddend.wings 306 form an upwardly facing shoulder 316 with
.Iadd.the .Iaddend.counter bore 302 and a downwardly, outwardly
facing shoulder 307 with .Iadd.the .Iaddend.enlarged counterbore
304. Passageways 54, 303, 137 and 236 are formed in the valve
collar 14" to be in communication to .[.interior.]. .Iadd.bore
.Iaddend.21 of .Iadd.the pipe .Iaddend.member .[.10.].
.Iadd.11.Iaddend., the external surface of valve collar 14" on the
outside of .[.tubular element.]. .Iadd.the packer .Iaddend.10, the
fluid channel 20 and the interior of .[.packer.]. .Iadd.the packing
element .Iaddend.30, respectively, and to .Iadd.the valve
.Iaddend.pocket 300. .[.The.]. .Iadd.A .Iaddend.valve element 318,
which is inserted into .Iadd.the valve .Iaddend.pocket 300,
includes .Iadd.a .Iaddend.first .Iadd.valve .Iaddend.body member
320 having .Iadd.an .Iaddend.upper surface 373 and .Iadd.a
.Iaddend.lower surface 346 located in .Iadd.the second
.Iaddend.counterbore 304, .Iadd.a .Iaddend.spring 322 located in a
.[.bore.]. .Iadd.first counterbore .Iaddend.302, and .Iadd.a
.Iaddend.second .Iadd.valve .Iaddend.body .[.element.].
.Iadd.member .Iaddend.324 having upper surface 372 .[. and.].
.Iadd.located in the bore 301 and a .Iaddend.lower surface 374
located in .[.bore 301 and.]. .Iadd.the .Iaddend.counterbore 302 in
the initial assembled position. .[.Passageway.]. .Iadd.The
passageway .Iaddend.303 has a lower surface 315 substantially
coplaner with .Iadd.the .Iaddend.spring 322 in the initial
assembled position. .[.First.]. .Iadd.The first valve .Iaddend.body
member 320 includes .Iadd.an .Iaddend.enlarged .Iadd.valve
.Iaddend.portion 330 having .Iadd.a .Iaddend.groove 332 formed
thereabout for reception of .Iadd.a .Iaddend.seal 334 therein.
.[.Seal.]. .Iadd.The seal .Iaddend.334 is sized to sealingly engage
the .[.sides.]. .Iadd.wall .Iaddend.of .Iadd.the
.Iaddend.counterbore 304 and the bottom surface 336 of .Iadd.the
.Iaddend.groove 332. .[.Stem.]. .Iadd.A valve stem
.Iaddend.338.[.,.]. .Iadd.on the valve body member is .Iaddend.of
smaller diameter than .Iadd.the enlarged valve .Iaddend.portion
330.[.,.]. .Iadd.and .Iaddend.extends from .Iadd.the enlarged valve
.Iaddend.portion 330 longitudinally to the end of .Iadd.the
.Iaddend.counterbore 304 approximately coplaner with
.[.shoulders.]. .Iadd.the shoulder .Iaddend.316. The diameter of
.Iadd.the valve .Iaddend.stem 338 is substantially less than the
diameter of .Iadd.the valve .Iaddend.body portion 330 and forms
.Iadd.a .Iaddend.shoulder 340 at the interface between the
.Iadd.valve .Iaddend.steam 338 and .Iadd.the valve .Iaddend.body
portion 330. .[.Stop wings 342 extend from stem 338..]. Stop wings
342 extend laterally from .Iadd.the valve .Iaddend.stem 338 and are
appropriately positioned along the length of .Iadd.the valve
.Iaddend.stem 338 to perform as set out below .Iadd.approximately
midway along the length of the valve stem 338.Iaddend.. The
longitudinal placement of .Iadd.the .Iaddend.stop wings 342 is
determined by the .[.length.]. .Iadd.dimension .Iaddend.of
.Iadd.the .Iaddend.shoulder 307. .[.Stop.]. .Iadd.The stop
.Iaddend.wings 342 must be sufficiently displaced from .Iadd.the
.Iaddend.shoulder 340 along the surface of .Iadd.the valve stem
.Iaddend.338 to permit .Iadd.the stop .Iaddend.wings 342 to extend
above .Iadd.the .Iaddend.shoulder 316 when .Iadd.the
.Iaddend.shoulder 340 meets the lower downwardly outwardly
extending surface 307. A first shear pin 344, or collet.Iadd.,
.Iaddend.or other suitable mechanism for prevention of
reciprocation, extends through the surface of .Iadd.the
.Iaddend.valve collar 14" and into the base 346 of .Iadd.the valve
.Iaddend.portion 330 .Iadd.and releasably holds the valve portion
330 in its initial position.Iaddend..
Spring 322 is of any suitable material having an inner diameter
larger than the diameter of .Iadd.the valve .Iaddend.stem 338 and
having a collapsed length substantially equal to the distance from
.Iadd.the .Iaddend.shoulder 316 to the lower surface 315 of
.Iadd.the .Iaddend.passageway .[.314.]. .Iadd.303.Iaddend..
.[.Upper.]. .Iadd.The upper .Iaddend.valve element .Iadd.or member
.Iaddend.324 includes .Iadd.a valve .Iaddend.base portion 350
having a diameter greater than the diameter of .Iadd.the
.Iaddend.bore 301. .[.Element.]. .Iadd.The upper valve element
.Iaddend.324 is reduced in size along .[.most of.]. the portion
extending away from .[.lower valve element 322.]. .Iadd.the valve
base portion 350 .Iaddend.to form a valve stem portion 352 having a
smaller diameter than .Iadd.the .Iaddend.bore 301 with a shoulder
354 formed at the juncture of .Iadd.the valve .Iaddend.stem
.Iadd.portion .Iaddend.352 and .Iadd.the valve .Iaddend.base
.Iadd.portion .Iaddend.350. Two grooves 356, 358 are formed along
the circumference of .Iadd.the valve .Iaddend.stem .Iadd.portion
.Iaddend.352 .Iadd.and .Iaddend.spaced such that circumferential
seals 360, 362 may be fit therein .Iadd.and .Iaddend.sealingly .[.
engaging.]. .Iadd.engage .Iaddend.the walls of .Iadd.the
.Iaddend.bore 301 and the walls 364, 366 respectively of .Iadd.the
valve .Iaddend.stem .Iadd.portion .Iaddend.352. Grooves 356, 358
are spaced apart sufficiently so that .Iadd.the .Iaddend.seals 362,
366 engage the walls on either side of .Iadd.the .Iaddend.passage
137 when .Iadd.the .Iaddend.shoulder 354 abuts .Iadd.the
.Iaddend.shoulder 368 formed between .Iadd.the .Iaddend.counterbore
302 and .Iadd.the .Iaddend.bore 301. A shear pin 369, or
collet.Iadd., .Iaddend.or other suitable mechanism for prevention
of reciprocation, extends through the surface of .Iadd.the
.Iaddend.valve collar 14" and into a bore 370 formed in .Iadd.the
.Iaddend.valve stem .Iadd.portion .Iaddend.352 upon initial
assembly .Iadd.and releasably holds the valve stem portion 352 in
its initial position.Iaddend..
Referring to FIGS. 9a-9c, in operation the pressure from the
.[.internal portion of tubular member 10.]. .Iadd.bore 21 of the
pipe member 11 .Iaddend.is applied .[.at.]. .Iadd.through the
.Iaddend.passageway 54 against .Iadd.the .Iaddend.surface 372 of
.Iadd.the .Iaddend.upper .[.member.]. .Iadd.valve body element
.Iaddend.324. .Iadd.At the same time, pressure in the borehole
external to the valve collar 14" is applied via passageway 303 to
the areas defined by seals 362 and 334 in the pocket. Pressure in
the borehole external to the valve collar 14" is applied via the
packing element 30 and the passageway 236 to the other side of seal
334 and is applied via the packing element 30 and to the passageway
137 to the portion of the bore 301 located between the seals 360
and 362. .Iaddend.When .[.this.]. .Iadd.the .Iaddend.pressure
.Iadd.within tubular pipe member 11 .Iaddend.is sufficient to
overcome the .Iadd. shear .Iaddend.strength of .Iadd.the
.Iaddend.shear pin 369, .Iadd.the .Iaddend.shear pin 369 shears
(FIG. 9b) permitting the pressure acting on .Iadd.the
.Iaddend.surface 372 to move .[.member.]. .Iadd.the second valve
body member .Iaddend.324 longitudinally towards .[.lower.].
.Iadd.second .Iaddend.valve .[.portion.]. .Iadd.body member
.Iaddend.320 and .Iadd.to .Iaddend.compress .Iadd.the
.Iaddend.spring 322. Accordingly, .Iadd.the .Iaddend.valve seal 360
no longer prevents flow of fluid from .Iadd.the .Iaddend.passageway
54 to .Iadd.the .Iaddend.passageway 137, and fluid then flows to
passageway 137 from passageway 54. Fluid in passageway 137 flows
into .Iadd.the .Iaddend.channel 20 and thence to the interior of
.[.packer.]. .Iadd.the packing element .Iaddend.30 and inflates
.[.packer.]. .Iadd.the packing element .Iaddend.30. Fluid
communication with the interior of the .[.packer.]. .Iadd.packing
element .Iaddend.30 is accomplished through .Iadd.the
.Iaddend.passageway 236 .[.and permits pressure to build in
passageway 236. When.]. .Iadd.equal to the pressure within the
packing element 30. It will be noted that the pressure area across
the seal 334 is larger than the pressure area across the seal 362
and thus when the .Iaddend.fluid in .Iadd.the .Iaddend.passageway
236 has reached a predetermined pressure, greater than or equal to
the pressure in .Iadd.the .Iaddend.passageway 303, as determined by
.Iadd.the shear force of the .Iaddend.shear pin 344 .[.and the
surface area of seal 334,.]. .Iadd.the .Iaddend.shear pin 344
shears (FIG. 9c) forcing .[.lower.]. .Iadd.the second valve body
.Iaddend.member 320 to rise .Iadd.or move .Iaddend.and the end
surface 373 of 171 upper.]. .Iadd.the second .Iaddend.valve
.Iadd.body .Iaddend.member 320 to abut the surface 374 of
.[.upper.]. .Iadd.first .Iaddend.valve .Iadd.body .Iaddend.member
324. Because the surface area of .Iadd.the .Iaddend.surface 346 is
substantially greater than the surface area of .Iadd.the
.Iaddend.surface 372, the pressure in .Iadd.the .Iaddend.passageway
236 acting on .Iadd.the .Iaddend.surface 346 will eventually force
both .[.lower.]. .Iadd.the second .Iaddend.valve .Iadd.body
.Iaddend.member 320 and .[.upper.]. .Iadd.the first .Iaddend.valve
.Iadd.body .Iaddend.member 324 to move through their respective
.[.pockets.]. .Iadd.bores .Iaddend.until .Iadd.the
.Iaddend.shoulder 340 .Iadd.on the second valve body member 320
.Iaddend.contacts .Iadd.the .Iaddend.inclined surface 307. At this
point, the seals 360, 362 .Iadd.on the second valve body member 320
.Iaddend. would be again spaced around .Iadd.or to either side of
the .Iaddend.passageway 137 to prevent further flow .Iadd.of fluid
.Iaddend.into the .Iadd.the .Iaddend.passageway 137 from passageway
54 thereby retaining the inflation .[.of.]. .Iadd.pressure in
.Iaddend.the .[.packers.]. .Iadd.packing element .Iaddend.30.
Should there .[.by.]. .Iadd.be .Iaddend.a small loss in pressure in
the passageway 236 against surface 346, the .[.optional.].
.Iadd.stop .Iaddend.wings 342 .Iadd.(which can be optional)
.Iaddend.would prevent .[.lower.]. .Iadd.the .Iaddend.valve
.Iadd.body .Iaddend.member 320 and .[.upper.]. .Iadd.the
.Iaddend.valve .[.element.]. .Iadd.body member .Iaddend.324 from
moving sufficiently to again permit flow between .Iadd.the
.Iaddend.passageways 54 and 137.
Although the system described in detail above is most satisfactory
and preferred, many variations in structure and method are
possible. For example, wings 342 may be eliminated. Also, the
members may be made of any material suitable for the environment.
Further, reciprocating member or .[.upper.]. valve .[.element.].
.Iadd.body member .Iaddend.324 may be split horizontally so that
the member has two pieces, each piece having one seal and the lower
seal being of a poppet type.
The above are examples of the possible changes or variations.
Because many varying and different embodiments may be made within
the scope of the inventive concept herein taught and because
modifications may be made in accordance with the descriptive
requirements of the law, it should be understood that the details
herein are to be interpreted as illustrative and not in a limiting
sense.
* * * * *