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Патент USA US2374317

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April 24, 1945.
K. AI WRlGHT
2,374,317
WELL PRODUCTION EQUIPMENT
Filed Dec. l0, 1940
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K. A_ WRlGHT
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WELL PRODUCTION EQUIPMENT
Filed Deo. 10, 1940
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2,374,317
Patented Apr. 24, 1945
UNITED STATES PATENT OFFICE
2,374,317
WELL PRODUCTION EQUIPMENT
Kenneth A. Wright, Los Angeles, Calif.
Application December 10, 1940, Serial No. 369,389
15 Claims.
This invention relates to well production equip
ment, and particularly pertains to inventions of
the general type shown in my (zo-pending appli
cation entitled “Method and means of condition
ing the walls of well bores,” Serial No. 291,027,
filed in the United States Patent Office by me on
August 19, 1939, and is a continuation _in part.
In preparing oil wells for production it is often
(ci. 16e-1s)
the cement to the wall of the well bore is ob
tained.
'
When it is desired to produce a Well through
a perforated casing which is placed in the Well,
the mud cake left on the wall of the Well bore
may retard or prevent the oil and/or gas or fluids
in the strata from entering the perforated cas
ing. It is desirable to remove this mud cake from
the wall of the well «bore prior to putting the well
necessary to set a perforated or flank casing in
the well, and it is also common practice to cement 10 on production. To do this the mud rcake must be
abraded and loosened from the wall of the well
casing in position within the well bore. In order
bore and then fluid must be circulated to carry
to do this the casing is lowered into the well
the loosened material from the hole. To accom
and is cemented in place 1by circulating the ce
plish this it is desirable to attach an a-brading
ment slurry downwardly through the casing and
member permanently to the perforated casing,
then upwardly within the well bore and around
which casing and abrading member remains with
the casing. The cement is intended to ñll the
in the well after the removal of the mud cake has
space Ibetween the casing and the walls of the well
been completed. Movement of the casing and
bore and to form a suitable 'bond with the side
abrading member may take place either up or
walls of the Well.
It has ‘been found in actual practice that mud 20 down within the bore or 'by rotation of the casing.
Attention is called to the fact that under normal
remaining on the walls of the well bore after
well conditions when a well is being drilled 0r a
drilling operations is often responsible for ce
casing set, the well is filled with drilling fluid.
mcnting failures due to the fact that the ñuid
This drilling ñuid carries an appreciable propor
which is circulated ahead of the cement, or the
tion of suspended solids which tend to settle out
cement itself, will not eiîectually remove the mud
of the suspending liquid and to deposit on the Wall
cake. The presence of mud cake on the walls of
of the well bore in a sheath. When various de
the well bore causes “channeling” and also pre~
vices have been used heretofore'to ream the wall
vents the cement from completely filling the an
of a well it has been necessary to remove those
nular space between the wall of the well bore and
the casing to form a bond between the actual wall 30 devices by withdrawing the complete assembly
from the well before a well casing could be set.
of the bore and the casing. The mud cake left
In such instances it will be appreciated that not
on the wall of the hole during cementing of a cas
only will the loosened material tend to accumu
ing. or the like. is often the cause of weakness
late in the bottom of the well Ibut that also the
which may result in failure of the cementingr
operation. This failure to obtain a Fbond as de 35 drilling ñuid standing in the well will cause an
additional sheath or layer to form on the wall
scribed, and also the channeling, may be respon
of the well during the time the reaming assem
bly is being removed and the time while the per
manent casing structure is being lowered into the
mingling of fluids or gas contained in such strata.
In order to obtain an effective cementing of 40 well. It is therefore desirable to provide a de
vice which will permit the wall of the well to be
the casing it is necessary that the bond of the
conditioned rapidly just as the casing is being set
cement with the well bore shall be continuous
without the necessity of an elapsed period of time
from the bottom of the casing to the top of the
occurring within which a new sheath of material
cemented area. It is also necessary to form a
may accumulate on the Wall of the well to defeat
continuous cementing bond behind the casing in
the very purpose sought to fbe obtained when the
any given strata and a failure of the cement may
wall was scraped.
result in undesirable leakage and in allowing
It is the principal object of the present inven
water to invade the producing zones. This failure
tion, therefore, to provide a means of condition
may also create high gas oil ratios or the flood
ing of producing zones by water. In order to 50 ing the wall of the `well bore rapidly so that ce
menting operations can `be aided and so that by
obtain the most effective cemcnting of well cas
removing the mud cake the exposed strata be
ing within a Well bore it is desirable to insure
hind the perforated casing in the well may pro
that uniform distribution of cement is made
duce its contained fluid and gas freely and per
around therasing and between it and the wall
of the well bore, and that uniform lbonding of 55 mit a casing to be promptly set before a new
sible for failure to effectively separate or isolate
one stratum from another and thus result in com- t
2
2,374,317
vïsheath of mud accumulates on the wall of the
well bore. It is also an object of the invention
to provide means i or centering the casing in the
well 'bore so that uniform spacing will occur
around the casing, the said method being simple
in its performance and embodying the use of an
inexpensive and easily operable means for ac
comfplishing the same.
Fig. 5 is an enlarged fragmentary view as seen
on the line 5-5 of Fig. 3 showing the cross
sectional formation of the ribs.
Fig. 6 is a view in perspective showing one of
the spring guide and cleaning elements of the
unit provided by the invention.
Referring more particularly to the drawings.
I0 indicates a well bore. Positioned within the
well bore is a string of casing II. This casing
a unit or device for abrading the wall of a well 10 may be perforate (as shown in Fig. 1‘ where it is
bore and for centering a casing in the bore, which
designated as IIß), or imperforate (as shown in
is characterized by novel spring elements an
Fig. l), as required, and may be fitted with a
chored to the body of the device in such a man
lplurality of cleaning and guide units as generally
ner that they may flex and work during opera
indicated at I2. It will be seen that' these units
tion with little or no danger of failure or detach 15 I2 may be spaced from each other throughout
ment. 'I‘he spring elements are of novel shape
a selected length of the casing, and-'that they act
to be effective in the ab'rading of the well wall
to position the casing centrally ofthe well bore
and in centering the casing in the well bore
I0.
l
without gouging into the earth formation and
'I'he lower end of the casing II is provided with
without becoming caught. 'I'he securing or an 20 a suitable guide shoe I3.
choring means for these spring elements is such
Where the casing II‘i is perforated or in the
that extensive integral shanks of the elements
nature of a screen as shown in Fig. ll, a remov
are subjected to a mild torque action when the
»able wash pipe 30 is lprovided to conduct fluid
elements are in operation, the torque being dis
therethrough. The wash pipe 3U extends longi
tributed along the Shanks for a substantial dis 25 tudinally through the casing to the shoe I3 so
tance so that there is no danger of permanent
that the fluid is conducted downwardly to the
distortion or fracture.
shoe for discharge into the well. A cleaning and
A further object of this invention is to provide
centering guide is shown in detail in Figs. 2 to
abradingv and casing centering devices of the
4 of the drawings. Here it will be seen that each
character referred to that are sturdy and depend 30 unit comprises an inner sleeve I4 secured on the
alble and yet are simple and inexpensive to man
casing II and around the circumference of
ufacture. 'I'he low cost of the albrading units
which are mounted ribs I5. The ribs I5 extend
allows the employment of an adequate number '
longitudinally of the sleeve and are secured at
of the units on the casingwhich is to be per
their opposite ends to the outer circumferential
manently set or cemented in the well.
35 face of the sleeve. By reference to Fig. 3 it will
The present invention contemplates the .pro
be seen that the opposite ends of the ribs, as in
vision of a well casing section, adapted to be per
dicated at I6, lie iiat against the circumferential
manently set within a well bore. and which cas
face of the sleeve and may be spot welded in
ing carries a plurality of yieldable wall guides or
place. The major portion of each rib, as indi
abrading units adapted to be manipulated or 40 cated at I1, is of angle section, having an outer
moved longitudinally or around in the bore, to
portion I8 parallel to the outer circumference of
clean the wall of the well b'ore and to space the
the sleeve and an inturned portion I9 stand
Another object of the invention is to provide
casing concentrically with relation thereto for
well cementing operations, the abrading op- .,
eration to be. accompanied by the circulation
of a desired fluid to remove or flush out of
the well bore the abraded and loosened mud cake.
This fluid may be any suitable fluid, such as
ingV substantially radially with respect to the
sleeve. The intumed portions I8 are formed with
a plurality of recesses 20 which are spaced apart
lengthwise of each rib and form guide seats for
the shanks 2l of the cleaning and spacing iin
gers 22.
water, oil, acid or alkaline solutions, or water
treated with desirable reagents, such as chemicals
for reducing surface tension. which chemicals are
known as wetting reagents.
The invention is illustrated by way of example
in the accompanying drawings, in which:
The spring finger structure is shown particu
larly in Fig. 6 of the drawings. Here it will be
seen that the shank portion 2l is arcuate and
as'indicated in Fig. 4 conforms to the outer cir
tion of Fig. 1 showing a slightly modified form
of the invention.
well bore I0. An upturned end part 24 is provided
cumference of the sleeve I4. At one end of the
spring element 2I the finger 22 occurs. 'I’his
Figure 1 is a vertical section of a well showing 65
'finger is arranged or shaped to assume a radial
a casing and device of the present invention in
position with relation to the circumference of the
elevation therein with la portion near the lower
sleeve. 'I'he length of the finger 22 is greater than
end broken away to show in section.
the width of the annulus or space 23 which oc
Fig. l* is a sectional view similar to a por
curs between the casing II and the wall of the
Fig. 2 is an enlarged view in transverse sec
tion as seen on the line 2--2 of Fig.' 1, and dis
closes the manner in which the casing is cen
on the outer end of each finger 22 to act on the
wall *of the well. 'I'he shank 2| and the finger
22 are‘ formed integral from a continuous piece
of round stock spring material. The end of the
tered in the well bore by the device of the present 05 spring shank portion 2I opposite from that
invention.
on‘which the finger 22 occurs is bent outwardly,
Fig. 3 is an enlarged view in side elevation
as indicated at 25, and extends through a per
showing one of the spacing and abrading units
foration 26 in the portion I1 of a rib beneath
provided by the invention in |place on a casing
which it terminates. The extending portion at
and with a portion broken away to show in sec 70 25 'is "riveted over" so that this end of the spring
tion.
Fig. 4 is an enlarged fragmentary view in
section and elevation as seen on the line 4-4
of Fig. 3, showing the construction of the guide
unit.
shank 2| is held in position.
By reference to Fig. 4 it will be seen that each
spring shank 2I is of substantial length. By ref
erence to Fig. 3 it will be seen that the spring and
finger elements 'are arranged in spiralled or hel
2,374,317
ical sets, the fingers 22 being disposed radially of
the sleeve and spaced consecutively around the
3
the width thereof. In the present instance ñve
Where the casing || is imperforate, as shown
in Fig. 1, the fluid is pumped down through the
casing and discharges from the shoe I3 to flow
upwardly through the annulus 23 to the ground
surface. When the casing employed is perfo
rated, as shown in Fig. 1a, the ñuld passes down
through the wash pipe 30 to discharge into the
well at the shoe I3 and returns upwardly through
the space between the casing Il and the well
10 wall. The ñuid thus circulated through the well
sets of springs are shown as thus arranged. The
serves vto carry away the solid matter or mud cake
sleeve in equal spaced relation to each other. The
consecutive ñngers 22 with their spring shanks
2| are disposed in separate horizontal planes as
' determined by the spacing and number of per
forations 20. Each set of springs and fingers lies
along a helix line extending substantially from
one edge to the other of the sleeve I4 and across
formation, proportions and mountings of the
spring insure that the spring ñngers 22 will uni
versally adapt themselves to the surface of the
well bore, whether in a cleaning or spacing oper
ation.
`
It is to be understood that since the spring
fingers 22 are all of the same radial length their
outer ends when unflexed terminate an equal
distance from the sleeve. Attention is also di
rected to the fact that since the arcuate spring
that is being removed from the well wall by the
abradingunits |2, serves to wash or clean the
well wall and operates to prevent'the mud from
15 re-depositing or re-forming on the abraded well.4
wall. The character of the fluid employed at this
stage of the operation may vary with the oper
ating conditions. In most instances the fluid
employed may be clean water or oil but, in other
cases, it may be desirable or necessary to employ
an acidizing solution or a solution containing a
shanks 2| extend for a considerable distance
wetting agent. The fluid may be circulated dur
around the circumference of the sleeve they ex
ing the entire abrading operation to carry away
tend beneath a plurality of ribs |5 and seat within
the major portion of the mud or material removed
a plurality of the recesses 20 in these ribs. Thus 25 from the well wall by the units I2. The wash pipe
the springs are each held at a plurality of points
30 is withdrawn following the abrading .and cir
to properly support the spring shank 2| and their
cullating operations and prior to producing the
ñngers 22 during a time when the spring iingers
we l.
are being flexed, It will he further seen that
When imperforate casing is being set, landed
since the ends of each of the spring portions 2| 30 or cemented, the abrading and the circulating
are anchored by their extensions 25 the spring
operations are celrrìed out simultaneously as
may be subjected to fa suitable torque action while
above described. As the abrading operation con
allowing swinging of the spring lingers longitudi
tinues cement slurry is usually substituted for
nally of the sleeve.
the circulating or mud iiJuid, that is, cement
In operation of the apparatus here disclosed and 35 slurry is passed down through the casing || and
a typical method to be practised the cleaning and
discharges from the shoe |.3 to occupy the an
centering guide units l2 are iixed on the casing
nulus 23 throughout a selected portion of the
in spaced relation to each other along a desired
well. The abrading action may be continued dur
length of the casing. This length of casing
ing the delivery of the cement slurry to assure the
should normally represent the thickness of strata 40 direct intimate contact of the cement slurry with
including the producing formation and the area
the virgin earth formation.
in which cementing operations are to be carried
It is to be observed that the guide members
onv The units l2 are proportioned so that a
|2 sustain the casing || in a position concentric
circumferential line including the ends of the
with the well bore so that a uniform thickness
spring iingers 22 has a diameter somewhat greater
of cement is provided around the casing and the
than the inside diameter of the well bore so that
cement fills the annulus of the well bore to a
as the casing is lowered into the hole the spring
selected level and bonds directly with the
ñngers frictionally and yieldingly engage the
clean native formation penetrated by the well
walls of the well bore, and ilex upwardlv as the
bore. . When the cement is set it will be evident
casing moves downwardly. The strength of the 50 that the well casing, together with the guide units
spring fingers is such that the collective action of
|2, will be held in the well permanently by the
cement, and that the presence of the guide units
the guide units tends to center the casing in the
well bore. It is desirable to mount the guide
including the plurality of fingers 22 imbedded
units l2 permanently on the casing || or well
within the cement will insure a thorough bond
screen as the case may be. The casing is lowered 55 and union between the cement and the well cas
ing.
into position in the well and then reciprocated
From the foregoing it will be evident that the
and/or rotated within the well bore for any de
following advantages are obtained by the prac
sired distance, such for example as a distance
tice of the present invention:
lgreater than that occurring between adjacent
(a) The advantage of cleaning the walls of a
guide units. As previously explained. when the 60
well bore just before and during the placing of
casing is moving downwardly, the fingers 22 flex
upwardly and the curved ends 24 ride along the
the cement slurry, removing the mud cake from
wall of the well bore while centering the casing.
the wall of the well bore, thus permitting actual
When a lifting. lowering or rotating ‘action is
contact between the cement and the walls of the _
produced the ends of the fingers 22 frictionally 65 fonmation.
(b) The advantage of agitating the cement
engage the well bore, and these fingers tend to
iiex so that the end points of the portions 24
while it is being lplaced in its ultimate position
-and location in the well bore and thus «preventing
scratch the walls of the well bore. This is ef
the channeling of the cement slurry.
fective in removing the mud cake. and since the
70
various ñngers 22 of each guide unit are _arranged
(c) The advantage of abrading the walls of
in staggered relation to each other the wall is
the well bore at the point where the cement is to
be placed.
simultaneously engaged in different planes so
that a thorough abrading action is effected. Dur
(d) The advantage of continuous centering of
ing this operation circulation is maintained to
flush the loosened material from the Well.
the casing throughout the productive section or
sections and removal of the mud cake from these
4
2,374,317
the circumference of the cylindrical member, a
sections while placing the cement, thus insuring
improved cement distribution and preventing
fluid migration behind the casing.
(e) 'I‘he advantage of obtaining a perfect seal
plurality of longitudinally extending and circum
ferentially spaced ribs upon the outside of said
cylindrical member having a, plurality of re
cessed seats spaced longitudinally of the ribs, the
seats of the ribs lying in parallel transverse
with cement in the annular space between the
casing and the walls of the formation.
where prevention of iiuid migration is necessary,
planes. the seats of a plurality of ribs in oneÍ plane
receiving the semi-resilient arcuate portion, and
means anchoring the free end of the semi-resil
which further prevents the cement slurry from
ient arcuate portion to one of said ribs, whereby
(j) The advantage of.' removing the mud sheath
from the wall of the well bore in those sections
channeling and provides a cleaned formation sur
face into which the excess mixing water from the
cement slurry may fllter.
It will thus be seen that the invention here dis
closed provides a simple and effective means for
cleaning a well bore preparatory to setting a cas- _
ing, and inexpensive means whereby the casing
may be centered in a well bor'e preparatory vto a
torque may be set up in the arcuate portion as
the finger swings longitudinally.
4. A device of the character described, com
prising a tubular cylindrical member adapted to
is
be lowered into a well bore, semi-resilient ele
ments carried thereby and spaced around the
cylindrical member, said elements each compris
ing a semi-resilient radially disposed finger ter
minating in a free upwardly curved outer end
While I have shown only a typical preferred 20 and being formed integral at its opposite end with
an arcuate semi-resilient element adapted to con
form of the means I have provided for clean
form to .the circumference of the cylindrical
ing a well wall of mud and for centering and ce
member, a plurality of longitudinally extending
menting a casing in a well'bore, it will be under
and circumferentially spaced. ribs upon the out
stood that various changes may be -made in the
invention by those skilled in the art without de 25 side of said cylindrical member having a, plu
rality of recessed seats spaced longitudinally of
parting from the spirit of the invention as
the ribs, the seats of the ribs lying in parallel
claimed, and it is to be further understood that
transverse planes, the seats of a plurality of ribs
this is a continuation in part of my co-pending
in one plane receiving the semi-resilient arcuate
application entitled “Method and means of con
ditioning the walls of a well bore,” Serial No. 30 portion, and means anchoring the free end of the
semi-resilient arcuate portion to one of said ribs,
291,027, filed in the United States Patent Oflice
whereby torque -may be set up in the arcuate
by me on August 19, 1939. I wish it understood
portion as the finger swings longitudinally, said
that I do not limit myself to the particular de
radial fingers in successive planes being circum
. tails or application of the invention herein set
ferentially spaced with relation to each other
forth, but wish to reserve to myself any variations
whereby the fingers will be arranged in groups
or modifications that may appear to those skilled
lying along a line of helix extending across the
in the art and fall within the scope of the follow
face of the cylindrical member and circumferen
ing claims.
tially thereof.
_
Having thus described my invention, what I
5. In well production equipment, a casing to
40
claim and desire to secure by Letters Patent is:
be permanently set in the well, a sleeve on the
1. In combination, a tubular casing to be per
casing, and a plurality of spring fingers spaced
manently installed in a well, a sleeve adapted to
around the circumference of the sleeve and pro
be secured on the casing to be lowered into a well
jecting outwardly from the sleeve to en'gage the
thereon, a plurality of abrading fingers project
ing from the sleeve in spaced relation to one an 45 wail of the well.
other, the outer free ends of said fingers being
6. In combination, a well casing to be perma
well cementing operation.
adapted to engage the wall of a well bore into
which the device is lowered, and means for yield
nently set in a well, a sleeve secured on the casing.
2. In combination, a tubularA casing to be per
manently installed in a well, a sleeve adapted to
7. In combination, a well casing to be perma
nently set in a well, a'sleeve secured on the cas
and a plurality of spring fingers secured to the
ably supporting said fingers on the sleeve whereby 50 sleeve and projecting substantially horizontally
the fingers may swing longitudinally of the sleeve.
therefrom to engage the wall of the well.
be secured on the casing to be lowered into a
ing, and a plurality of spring fingers secured to
well thereon, a plurality of radially projecting
the sleeve and projecting substantially radially
abrading fingers arranged in spaced relation 55 therefrom, the outer portions of the fingers being
around the sleeve, the outer free ends of said fin
gers being adapted to engage the wall of a well
bore into which the device is lowered, and means
upturned and adapted to act on the wall of the
well.
8. In combination, a well casing to be perma
yieldably anchoring said fingers on the sleeve
nently set in a well, a sleeve secured on the cas
whereby the fingers may swing longitudinally of 60 ing,
a plurality of spring members each including
the sleeve, said fingers being disposed in sets of
an elongate shank and a finger projecting from
fingers lying in spaced transverse planes and with
an end of the shank, and means confining the
the fingers in each plane being uniformly spaced
Shanks of said members against the periphery of
circumferentially and the iingers‘in the several
the sleeve to extend circumferentially thereof so
planes being disposed out of axial alignment with
each other.
~
that the ñngers project substantially radially
from the sleeve to engage the wall of the well.
3. A device of the character described, compris
9. In combination, a well casing to be perma
ing a tubular cylindrical member adapted to be
nently set in a Well, a sleeve secured on the cas
lowered into a well bore, semi-resilient elements
carried thereby and spaced around the cylindri 70 ing, a plurality of spring members each includ
ing an elongate shank and a finger projecting
cal member, said elements each comprising a
semi-resilient radially disposed finger terminat
from an end of the shank, and means for hold
ing in a free upwardly curved outer end and being
ing said shanks against the exterior of the sleeve
formed integral at its opposite end with an arcu
to extend circumferentially thereof so that said
ate semi-resilient element adapted to conform to 75 ñngers project outwardly from the sleeve to con
2,374,317
tact the well wall, the contact of the fingers with
the wall subjecting said Shanks to torque.
10. A device for use on a well casing compris
ing a sleeve to be secured on the casing, a plu
rality of flexible resilient members each com
prising an arcuate shank adapted to conform to
the sleeve when extending circumferentially
thereof, and a finger adapted to project outward
ly from the sleeve to engage the wall of the well,
and means for holding said Shanks where they
conform to the sleeve and allowing the applica
tion of torsion to the Shanks when said ñngers
engage the well wall.
11. A device for use on a well casing comprising
a sleeve to be secured on the casing, a plurality
5
13. A device for use on a well casing compris
ing a sleeve to be coniined on the casing, a plu
rality of 'flexible resilient members each compris
ing an arcuate shank adapted to conform to the
sleeve when extending circumferentially there
of. and a finger on one end of the shank adapted
to project outwardly from the sleeve, and means
for holding said Shanks in general conformance
to the sleeve so that the Shanks form torsion
10 spring anchors for the fingers, said means in
cluding longitudinally extending ribs on the
Sleeve engaging over the Shanks, and end parts
on the other ends of the Shanks cooperating with
said ribs to anchor Said other ends of the Shanks.
14. A device for use on a well casing compris
ing a sleeve to be Secured on the casing, a plu- .
of flexible resilient members each comprising an
rality of flexible resilient members each com
arcuate Shank adapted to conform to the sleeve
prising an arcuate Shank adapted to conform
when extending circumferentially thereof, and a
to the sleeve when extending circumferentially
finger on one end of the shank adapted to pro
ject outwardly from the sleeve, and means for 20 thereof, and a n_nger on .pne end of the shank
adapted to project outw’agiiüly from the sleeve,
holding said Shanks in general conformance to
and means for holdinglsai'd Shanks in general
the sleeve so that the Shanks form torsion spring
conformance to the Sleeve so that the Shanks
anchors for the fingers, said means including
form torsion Spring anchors for the fingers, Said
parts on the sleeve engaging each shank at cir
cumferentially spaced points.
12. A device for use on a well casing compris
ing a sleeve to be secured on the casing, a plu
rality of flexible resilient members each com
25 means including circumferentially spaced longi
tudinally extending ribs on the sleeve extending
over the Shanks and having recesses on their
inner Sides receiving the Shanks, and 4bent over
parts on the other ends of the Shanks engaging
prising an arcuate shank adapted to conform to
the sleeve when extending circumferentially 30 the ribs to prevent bodily turning of the Shanks
and circumferential movement of the Shanks.
thereof, and a finger on one end of the shank
15. In combination, a perforate well casing in
adapted to project outwardly from the sleeve,
tended to be permanently installed in the well,
and means for holding Said Shanks in general
a sleeve secured on the casing, and a plurality of
conformance to the sleeve so that the Shanks
form torsion spring anchors for the fingers, said 35 Spring members projecting substantially radially
from the Sleeve for acting on the wall of the well.
means including longitudinally extending ribs
KENNETH A. WRIGHT.
on the sleeve engaging over the Shanks.
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