U.S. patent application number 11/047695 was filed with the patent office on 2005-08-11 for apparatus and method for repair of underground conduits.
This patent application is currently assigned to LINK-PIPE, INC.. Invention is credited to Maimets, Lembit.
Application Number | 20050173115 11/047695 |
Document ID | / |
Family ID | 34829816 |
Filed Date | 2005-08-11 |
United States Patent
Application |
20050173115 |
Kind Code |
A1 |
Maimets, Lembit |
August 11, 2005 |
Apparatus and method for repair of underground conduits
Abstract
Apparatus and method for repairing underground conduits, such as
well casings, particularly for repairing internal casings of deep
wells. More particularly, the invention relates to a filter-sleeve
and a method of conduit repair using such sleeve, without complete
removal of the conduit or casing and without abandoning the
well.
Inventors: |
Maimets, Lembit; (Richmond
Hill, CA) |
Correspondence
Address: |
GREENBLUM & BERNSTEIN, P.L.C.
1950 ROLAND CLARKE PLACE
RESTON
VA
20191
US
|
Assignee: |
LINK-PIPE, INC.
Ontario
CA
|
Family ID: |
34829816 |
Appl. No.: |
11/047695 |
Filed: |
February 2, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60541938 |
Feb 6, 2004 |
|
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Current U.S.
Class: |
166/277 ;
166/207; 166/227 |
Current CPC
Class: |
E21B 29/10 20130101;
E21B 43/103 20130101 |
Class at
Publication: |
166/277 ;
166/207; 166/227 |
International
Class: |
E21B 029/00; E21B
023/00 |
Claims
What is claimed is:
1. A filter-sleeve for lining at least a portion of an underground
conduit comprising: a perforated core coiled around a longitudinal
axis adapted to be expanded within the underground conduit at a
site of repair; and a filtering material surrounding the perforated
core.
2. A filter-sleeve according to claim 1, wherein the core comprises
a rolled corrugated metal sheet.
3. A filter-sleeve according to claim 1, wherein the core comprises
a rolled plain metal sheet.
4. A filter-sleeve according to claim 1, wherein the core comprises
a rolled stainless steel sheet.
5. A filter-sleeve according to claim 1, wherein the core comprises
a coated steel or plastic sheet.
6. A filter-sleeve according to claim 1, wherein the core is
equipped with a locking device to facilitate locking of the core at
the site of repair.
7. A filter-sleeve according to claim 1, wherein the filtering
material comprises felt, wire sieve, or a perforated sheet.
8. A filter-sleeve according to claim 1, further comprising at
least one O-ring surrounding the filtering material and for
retaining the core in a coiled position for transporting the
filter-sleeve to the site of repair.
9. A filter-sleeve according to claim 1, further comprising an
external protective material positioned over the filtering
material.
10. A filter-sleeve according to claim 1 in combination with an
expandable installation plug, wherein the filter-sleeve is coiled
around the installation plug and is securely affixed to the
installation plug.
11. A combination filter-sleeve/plug combination of claim 10,
further comprising a plurality of adhesive tapes, each of the tapes
having a first portion attached to an end portion of the
installation plug and to an inner surface of the filter-sleeve.
12. A method of lining a host casing using the filter-sleeve
according to claim 1, the method comprising: coiling the core of
the filter-sleeve on an inflatable installation plug to thereby
produce a filter-sleeve/plug assembly; inserting the
filter-sleeve/plug assembly into an underground host casing and
positioning the assembly at a location to be lined with the
filter-sleeve; expanding the inflatable installation plug to
thereby expand the filter-sleeve and locking the filter-sleeve in
place within the host casing.
13. A method of lining a host casing according to claim 12, wherein
the filter-sleeve includes O-ring(s), or other type of support
device(s), surrounding the core for tightly fitting the
filter-sleeve into the host casing and for supporting the filtering
material.
14. A method according to claim 12, further comprising deflating
and removing the installation plug from the host casing.
15. A method according to claim 14, wherein the filter-sleeve/plug
assembly further comprises a plurality of adhesive tapes, each of
the tapes having a first portion attached to an end portion of the
installation plug, or to a portion of the assembly other than the
filter-sleeve, and to an inner surface of the filter-sleeve, the
method further comprising, after deflating the installation plug,
raising the installation plug through the filter-sleeve and, during
such raising, stripping the tapes from the inner surface of the
filter-sleeve.
Description
[0001] This application is based upon U.S. Patent Application No.
60/541,938, filed on Feb. 6, 2004, the disclosure of which is
hereby incorporated-by-reference thereto in its entirety and the
priority of which is claimed under 35 USC .sctn. 119(e).
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to repairs of underground conduits
and, more particularly, repairs and linings of internal well
casings. More particularly, the invention relates to such repairs
and linings, utilizing a filter-sleeve, without complete removal of
the casing or abandonment of the well.
[0004] 2. Description of Background and Relevant Information
[0005] For the purpose of repairing an underground pipe, such as a
well casing, it is commonly necessary to remove the casing or to
abandon the well in favor of a new well in view of the limitations
of known technology.
[0006] A damaged well casing allows soil fines to enter the well.
This can cause severe damage to pumps and other equipment.
[0007] The state of the art of repairing well casings and other
underground pipes and conduits remains in need of a convenient and
effective method and apparatus for repairing and sealing
underground conduits, pipes, and casings, including those with
screen sections, without removing such conduits, pipes, and
casings, including such repair consisting of a complete
relining.
SUMMARY OF THE INVENTION
[0008] An object of the invention is to provide for the structural
repair and sealing of damaged underground conduits and pipes,
particularly well casings, including casings having screen
sections, by means of the installation of an expandable sleeve,
thus creating support for the structurally weakened conduit, pipe,
or casing.
[0009] An additional object of the invention to provide for the
repair of damaged screens and openings, which might be incorporated
within a damaged conduit, with a filter that can prevent the
ingress of fines and sand into such conduit.
[0010] A still further object of the invention is to provide a
means of continuing repair and maintenance of clogged and damaged
filters with a screen that can be installed and removed for the
purpose of replacement or cleaning, as the need arises.
[0011] A still further object of the invention is to provide a
means by which the service life of a well, or other underground
conduit, can be extended.
[0012] A sleeve according to the invention, hereafter referred to
as a filter-sleeve, includes an expandable perforated
non-corrodible core, such as a stainless steel core, equipped with
a locking mechanism. The choice of core material is determined by
the chemical regime in the well.
[0013] The core of the sleeve, according to a particular embodiment
of the invention, is surrounded by filter material. According an
embodiment of the invention, O-rings or other types of soft,
possibly elastic, support devices are positioned on the sleeve,
which can press the filter tightly against the host pipe upon
expansion and installation of the filter-sleeve, which can create
the pressure needed to secure the sleeve in place.
[0014] Installation, according to the invention, can be
accomplished by use of an inflatable plug as an installation tool.
Once the sleeve is expanded by means of the plug and locked by a
locking device or other type of fastener, the plug is removed.
[0015] Infiltrating water, upon installation of the filter-sleeve,
can pass through the filter material and the perforated sleeve.
[0016] The filter-sleeve of the invention provides an internal
repair method and apparatus, designed for rehabilitation of
conduits, pipes, well casings, and screens. The filter-sleeve can
be used to repair holes, cracks, corrosion and other damage.
BRIEF DESCRIPTION OF DRAWINGS
[0017] Other objects, features, and advantages of the invention
will be become apparent from the description of preferred
embodiments of the invention, when considered in light of the
accompanying drawings, in which:
[0018] FIG. 1 is a schematic illustration, in longitudinal cross
section, of a filter-sleeve according to the invention;
[0019] FIG. 2 is a schematic illustration of a filter-sleeve
combined with an installation plug to bring the filter-sleeve to
the repair site;
[0020] FIG. 3 is a schematic perspective view illustrating the
filter-sleeve combined with an installation plug, CCTV camera, and
weight, being lowered into a damaged pipe;
[0021] FIG. 4a is a schematic perspective view illustrating the
filter-sleeve combined with an installation plug, placed over a
damaged area;
[0022] FIG. 4b is a schematic perspective view illustrating the
filter-sleeve expanded by the installation plug and locked in
place;
[0023] FIG. 5a is a schematic perspective view illustrating the
filter-sleeve installed, the installation plug with camera being
lowered;
[0024] FIG. 5b is a schematic view of the interior of the
filter-sleeve showing a verification that the locks of the sleeve
have been secured;
[0025] FIGS. 6a, 6b, and 6c are schematic illustrations of the
relative position between the filter-sleeve and the installation
plug during different phases of the method of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0026] FIGS. 1-6 schematically illustrate an exemplary apparatus
according to the invention, as well as an exemplary manner by which
such apparatus can be employed in making well repairs. However, the
breadth of the invention is not intended to be limited by the
particular illustrations and particular descriptions of such
illustrations of the exemplary embodiments described herein, and is
applicable to the repair of other types of conduits and pipes,
particularly underground conduits and pipes.
[0027] FIG. 1 shows a filter-sleeve 1 according to the invention,
in a schematic longitudinal cross section positioned within a well
casing 9, or host pipe. As seen in FIG. 1, the well casing 9 has a
damaged area 10, in the form of a hole, over which the
filter-sleeve 1 is to be installed. Such damage can be created, for
example, by electrolytic corrosion caused by the electrical current
of a pump motor within the well/casing or a break caused by ground
movements.
[0028] The filter-sleeve includes a core 2, that can be rolled from
plain or corrugated sheet metal, such as stainless steel, plated or
coated steel or plastic sheet, depending upon the chemical regime
in the host casing/pipe 9.
[0029] The core 2 of the filter-sleeve 1, which can include a
plurality of drain holes 6, is equipped with a locking arrangement,
such as locks 8, or other types of fasteners, for locking the
filter-sleeve according to any of a number of patents, in the name
of the inventor of the instant invention, in the technology of
no-dig repair, i.e., repair of underground pipes and conduits
without excavation of the site of the repair. Among such patents,
the disclosures of the following of which are hereby incorporated
by reference thereto in their entireties, are U.S. Pat. No.
5,119,862, U.S. Pat. No. 5,351,720, and U.S. Pat. No. 6,138,718,
which disclose methods and apparatus for making such repairs, using
a repair sleeve that is transported to the location of damage of a
host pipe, and fixed in place with an inflatable/expandable
installation plug, the plug thereafter removed from the repair
site.
[0030] The filter-sleeve 1 shown in FIG. 1 preferably includes a
reinforcing coiled plate 3 equipped with drain holes. This optional
plate can take the form of a second core made of stainless steel,
for example, which is also perforated to allow water to
penetrate.
[0031] The filter component of the filter-sleeve 1 shown in FIG. 1
is made from a suitable filtering material, such as felt 5,
although such material could comprise a wire sieve, perforated
sheet, or other porous material.
[0032] Further, the filter-sleeve 1 shown in FIG. 1 includes
O-rings 4 or other type of support devices for the purpose of
tightly fitting the filter-sleeve in the well casing 9, or host
pipe, and for the purpose of supporting the filtering material.
[0033] The filter-sleeve 1 shown in FIG. 1 also includes an
optional external protective netting or mesh 7, or other protective
material.
[0034] Only as an exemplary embodiment of the invention, for a host
pipe/well casing 9 having an internal diameter D.sub.hp of 15.25
inches (38.74 mm), the body of the core 2 of the filter-sleeve
shown in FIG. 1 has an outer diameter D.sub.sl, of approximately 14
inches (35.56 mm) and a length L of approximately 24 inches (60.96
mm). Obviously, however, the invention encompasses the lining and
repair of pipes/casings of any size, the components of the
filter-sleeves then being sized appropriately to accomplish the
objectives consistent with the invention.
[0035] FIG. 2 is a schematic illustration of a filter-sleeve 1
coiled down upon and securely fitted onto an inflatable
installation plug 11, thereby forming a sleeve/plug assembly which
is then lowered into a well casing 9 that is in need of repair. For
this purpose, the upper end 11a of the plug 11 is connected to a
coupling 12 via chains 13 or other attachment mechanism, thereby
suspending the plug 11 by means of a cable, wire, or rope, for
example, from an operational/monitoring station above ground.
[0036] The vertical alignment of the sleeve/plug assembly shown in
FIG. 2 is adjusted by the weight 14 attached to the bottom of the
plug 11. Also shown in FIG. 2 are a plurality of optional safety
tapes 15, made of PVC, e.g., which are attached to the upper end of
the plug 11 or to the chains 13 or cable supporting the sleeve/plug
assembly, and to the interior of the filter-sleeve 1. The function
of the safety tapes 15, if used, is explained below in connection
with FIGS. 6a, 6b, and 6c. In short, in the event the plug 11 were
to lose its adherence to the filter-sleeve, the filter-sleeve can
then retain its attachment to the plug 11 by being secured by the
tapes 15 to the interior surface of the core of the filter-sleeve
and to the top of the plug.
[0037] A band of tape 16, such as adhesive tape or other equivalent
means, can be used to surround the entire assembly, at the bottom
thereof as shown in FIG. 2, to assist in maintaining the various
components of the filter-sleeve in place as the assembly is lowered
into position.
[0038] An air hose 17 is fitted to the sleeve/plug assembly, as
shown in FIG. 2, for use to inflate the expandable plug 11 as
needed at the site of the repair in positioning the sleeve in
place. Although air pressure is preferred for this purpose, water
can be used for inflating the plug. Often, the free water surface
in a well can be quite deep. Just by filling the hose the necessary
installation pressure is created. The only complication using water
for this purpose is providing for the release of the water after
the installation is completed. This can be done, however, by using
a valve, such as a pipe surrounding a sleeve that is part of the
aforementioned hose. The sleeve would have a hole in it. During the
installation, the pipe covers the hole. When the pressure must be
released, the pipe is slid upwardly letting the water escape
through the hole.
[0039] In FIG. 3, the filter-sleeve 1 and installation plug 11,
forming the aforementioned sleeve/plug assembly, with weight 14, is
shown being lowered into a damaged pipe 9, i.e., host casing. At
the top of the assembly a CCTV camera 18 is positioned for use
during the positioning of the assembly within the damaged pipe and
for use during the repair.
[0040] FIG. 4a schematically illustrates the sleeve/plug assembly
having been lowered and positioned in place over the damaged area
10 of the pipe 9.
[0041] FIG. 4b schematically illustrates the filter-sleeve 1 having
been expanded, by means of the installation plug, according to
methods taught by the inventor in any of the aforementioned
patents, for example, to securely lock the filter-sleeve 1 in place
within the pipe 9.
[0042] The protective mesh 7, if used, protects the felt 5, or
other filtration material, during the expansion of the plug 11. In
FIGS. 3, 4a, 4b, and 5a, the circular ribbed outer surface of the
filter-sleeve is the filter felt 5. The ribbed appearance results
from the fact that the felt is soft and rests upon the
aforementioned O-rings 4 shown in FIG. 1.
[0043] As the expansion of the plug causes the filter-sleeve 1 to
reach the desired diameter, the locks 8 of the sleeve (or other
locking device or fasteners) are caused to engage and thereby lock
the filter-sleeve in a suitable expanded diameter, as is generally
known in the art, such as disclosed in the aforementioned patents.
The elasticity of the O-rings, upon deflation of the plug 11,
effect the locking of the locks 8.
[0044] FIG. 5a schematically illustrates the filter-sleeve 1
installed within the pipe and the installation plug 11, with camera
18, being lowered through the interior of the filter-sleeve 1, so
that the proper engagement of the locks 8 thereof. FIG. 5b
illustrates the interior of the filter-sleeve, and a verification
that the locks 8 along the length of the sleeve have been properly
secured.
[0045] At the conclusion of the installation, following the
aforementioned verification that the repair has been successfully
completed, the installation plug and other accessories fitted with
the plug are then raised and removed from the casing/pipe 9.
[0046] FIGS. 6a, 6b, and 6c are schematic illustrations showing the
relative position between the filter-sleeve and the installation
plug during different phases of the method according to the
invention. Also shown in these figures is a schematic depiction of
the adhesive safety tapes 15, the use of which had been mentioned
above as optional in connection with the creation of the
filter-sleeve/installation plug assembly shown in FIG. 2.
[0047] For the sake of convenience in understanding, the host pipe
9 has been omitted from FIGS. 6a, 6b, and 6c and reference numerals
are not duplicated throughout these figures.
[0048] In FIG. 6a, the filter-sleeve 1 and the installation plug 11
are shown in their combined position shown in FIG. 2. In FIG. 6a,
however, a plurality of adhesive safety tapes 15 are shown for
ensuring that the filter-sleeve 1 does not slip off of the plug in
the event, as mentioned above, the assembly were to be lowered deep
within a well with sufficiently low temperatures that, for this or
for another reason, the sleeve 1 were to lose its adherence to the
plug. As shown in this optional feature of the invention, the
plurality of tapes 15 are adhered to both the interior surface of
the filter-sleeve 1 and to the plug 11. As can be seen in each of
FIGS. 6a, 6b, and 6c, the lower ends of the tapes 15 are fixed to
the lower end of the plug 11. While the filter-sleeve 1 and
installation plug 11 are positioned as shown in FIG. 6a, of course,
according to the description above, the assembly of filter-sleeve 1
and installation plug 11 is maintained as a unit by means of a
slight expansion of the expandable/inflatable plug applying
pressure from within the coiled sleeve 1.
[0049] After the filter-sleeve has been locked in place by the
expansion of the inflatable plug 11 and the locking of the
filter-sleeve against the well casing/pipe, as explained above, the
deflated installation plug 11 is then lowered through the interior
of the filter-sleeve 1, as shown in FIG. 6b, for verifying the
success of the repair by use of the CCTV camera as described above.
This relative position of plug 11 and sleeve 1 shown in FIG. 6b is
also shown in FIG. 5a, although in the latter figure the tapes 15
are not shown.
[0050] In FIG. 6a, as the filter-sleeve/plug assembly is suspended
by the cable 19 and before the filter-sleeve is locked in place
against the inner surface of the casing, the filter-sleeve 1 is
prevented from inadvertently falling downwardly relative to the
plug by virtue of the attachment of the tapes 15. However, as shown
in FIG. 6b, the plug 11 itself is able to be lowered relative to
the installed filter-sleeve 1 for the purpose of the verification
step. The lower ends of the tapes 15, as shown in FIG. 6b, provide
sufficient slack for this.
[0051] Finally, as the installation plug 11 and other accessories
fitted with the plug are raised from the casing/pipe, as shown in
FIG. 6c at the conclusion of the installation, the adhesive tapes
15 are peeled off of the inner surface of the installed
filter-sleeve 1.
[0052] The filter-sleeve 1 of the invention forms a short single
repair filter-sleeve in place. Alternatively, particularly in the
case of a large damage area, or a damage area that extends along
the casing/host pipe 9, a plurality of filter-sleeves can be
successively installed to thereby form a multi-filter-sleeve repair
inside the casing/host pipe.
[0053] After the filter-sleeve, or multi-filter-sleeve, is locked
in place, the filter prevents fines and sand from entering the pipe
and clean water passes through the felt, or other filtration
material, and through the perforated sleeve into the pipe.
[0054] Over time, the fines and sand will clog the filter. The
clogged filter can then be removed, cleaned for reuse, or
replaced.
* * * * *