U.S. patent number RE31,265 [Application Number 06/033,650] was granted by the patent office on 1983-06-07 for method and apparatus for making subsea pipe connections.
This patent grant is currently assigned to Exxon Production Research Co.. Invention is credited to Joseph A. Burkhardt, Thomas W. Childers, Arthur C. Daughtry, Albert R. Sinclair.
United States Patent |
RE31,265 |
Sinclair , et al. |
June 7, 1983 |
Method and apparatus for making subsea pipe connections
Abstract
A subsea pipeline hub is connected to the hub of an adjacent
spool piece connected to an in-place manifold of a subsea structure
used in the production of oil and/or gas. The pipeline hub is
positioned relative to the opposing spool hub and a remotely
operated pipeline connecting tool is lowered from the water's
surface to the subsea structure using guidelines and structural
guidance for alignment of the pipeline hub with the spool piece
hub. The spool piece hub is then drawn to the pipeline hub and the
hubs are clamped together by operation of the connecting tool. The
seal in the connection can be tested by means of the connecting
tool. The spool piece may be retrieved and replaced by the
connecting tool if maintenance is needed. Connecting tool
operations are powered by hydraulic fluid and controlled from the
surface. The pipeline hub may be lowered vertically and pivoted
into its position adjacent the spool piece or may be pulled into
that position.
Inventors: |
Sinclair; Albert R. (Houston,
TX), Daughtry; Arthur C. (Houston, TX), Childers; Thomas
W. (Mandeville, LA), Burkhardt; Joseph A. (New Orleans,
LA) |
Assignee: |
Exxon Production Research Co.
(Houston, TX)
|
Family
ID: |
26709959 |
Appl.
No.: |
06/033,650 |
Filed: |
April 26, 1979 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
667758 |
Mar 17, 1976 |
04019334 |
Apr 26, 1977 |
|
|
Current U.S.
Class: |
405/169; 285/18;
29/237; 405/170 |
Current CPC
Class: |
E21B
43/0107 (20130101); F16L 37/002 (20130101); F16L
1/26 (20130101); Y10T 29/5367 (20150115) |
Current International
Class: |
E21B
43/00 (20060101); E21B 43/01 (20060101); F16L
37/00 (20060101); F16L 001/04 () |
Field of
Search: |
;405/168,169
;166/338-347 ;29/237 ;285/18,24,27,DIG.21,137 ;251/63.6 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Taylor; Dennis L.
Attorney, Agent or Firm: Schneider; John S.
Claims
Having fully described the nature, operation, advantages and
apparatus of our invention we claim: .[.1. A method for connecting
a spool piece hub, connected to a subsea structure manifold, to a
fixed pipeline hub aligned for connection to said spool piece hub
comprising the steps of:
1owering a remotely operated connecting tool from the water's
surface;
guiding said connecting tool onto said pipeline and said
manifold;
1atching said connecting tool to said spool piece;
moving said spool piece hub by means of said connecting tool into
engagement with said pipeline hub; and
clamping said engaged hubs together by means of said connecting
tool..]. .[.2. A method as recited in claim 1 including supplying
test fluid to said hub connection to test the seals
therebetween..]. .[.3. A method as recited in claim 2 including
unlatching said connecting tool from said spool piece and
retrieving said connecting tool..]. .[.4. A method as recited in
claim 3 in which prior to lowering said connecting tool from the
water's surface lowering said pipeline hub attached to a pivotal
trunnion assembly from the water's surface vertically; guiding said
trunnion assembly to a prepared location on said subsea structure
and releasably securing said trunnion assembly to said subsea
structure, said pipeline hub being rotated from said vertical
position to a horizontal position and into alignment position with
said spool hub as additional sections of pipe are added from a pipe
laying vessel..]. .[.5. Apparatus for connecting a spool hub,
connecting to a subsea structure manifold, to a fixed pipeline hub
aligned for connection with said spool hub comprising:
clamp means arranged on said spool hub for clamping said spool hub
and pipeline hub together; and
a remotely operated connector tool including:
guidance means engageable with said manifold;
1anding means engageable with said pipeline hub;
means connecting said guidance means and said landing means for
moving said spool hub into engagement with said pipeline hub;
means for engaging said clamp means for operating said clamp means
to clamp said spool piece hub and pipeline hub together; and
means for releasably locking said connector tool to said spool
piece..]. .[.6. Apparatus as recited in claim 5 including conduit
means associated with said clamp means for supplying test fluid to
said clamped hubs and means on said connecting tool for connecting
said conduit means to a source of test fluid to test the connection
between said hubs..]. .[.7. Apparatus as recited in claim 6
including a pivotal trunnion connected to said pipeline hub and
releasable means securing said turnnion assembly to said subsea
structure..]. .[.8. Apparatus as recited in claim 7 wherein said
spool piece comprises a valve spool..]. .[.9. Apparatus as recited
in claim 8 including a manifold hub on said manifold and said
guidance means including a yoke for engaging said manifold hub..].
.[.10. Apparatus as recited in claim 9 in which said connecting
tool includes spaced apart adjustable plates engaging said spool
piece, said plates containing guide means, wrench means, and motor
means for operating said wrench means; and said spool piece
containing guide posts engageable with said guide means and said
clamp means containing wrench heads engageable with said wrench
means..]. .Iadd.11. A method for use in connecting and
disconnecting a spool piece to and from, respectively, spaced-apart
first and second subsea pipes comprising:
1owering a remotely operable pipe connecting-disconnecting tool
from the water's surface to said underwater pipes, said tool being
capable of latching to and unlatching from two spaced-apart clamp
assemblies, one at each end of said spool piece; one of said clamp
assemblies being capable of clamping one end of said spool piece to
said first subsea pipe and the other of said clamp assemblies being
capable of clamping the other end of said spool piece to said
second subsea pipe;
guiding said tool onto said first and second subsea pipes, said
first subsea pipe being clamped to said one end of said spool piece
by means of said one of said clamp assemblies;
moving said other end of said spool piece into engagement with said
second subsea pipe by means of said tool; and
operating said other clamp assembly by means of said tool to clamp
said other end of said engaged spool piece and said second subsea
pipe together. .Iaddend. .Iadd.12. A method as recited in claim 11
including testing at least one of said clamped spool piece
connections for leaks. .Iaddend. .Iadd.13. A method as recited in
claim 12 including unlatching said tool from said clamp assemblies
and retrieving said tool to the water's surface. .Iaddend.
.Iadd.14. A method as recited in claim 13 wherein said subsea pipe
comprises a pipeline and includes
1owering said pipeline attached to a pivotal trunnion assembly from
the water's surface prior to lowering said tool from the water's
surface;
guiding said trunnion assembly to a subsea template at said pipe
location; and
releasably securing said trunnion assembly to said subsea template,
said pipeline being rotated from a vertical position to a
horizontal position and into alignment position with said spool
piece as additional sections
of pipe are added from a pipelaying vessel. .Iaddend. .Iadd.15. A
method as recited in claim 13 including:
1owering said tool to said underwater location;
guiding said tool onto said first and second subsea pipes;
1atching said tool to each of said clamp assemblies; operating said
clamp assemblies by means of said tool to unclamp said engaged
first subsea pipe-spool piece and said engaged second subsea
pipe-spool piece connections;
disengaging said one end of said spool piece from said first subsea
pipe and disengaging said other end of said spool piece from said
second subsea pipe by means of said tool; and
raising said spool piece and said clamp assemblies latched thereto
to the water's surface by means of said tool. .Iaddend. .Iadd.16. A
method as recited in claim 15 including
1owering said tool containing said spool piece and two clamp
assmemblies from the water's surface to said underwater
location;
guiding said tool onto said first and second subsea pipes;
moving said second subsea pipe into engagement with said other end
of said spool and moving said one end of said piece into engagement
with said first subsea pipe by means of said tool;
operating said clamp assemblies by means of said tool to clamp said
spool piece to said first and second subsea pipes;
testing each of said connections for leaks; and
unlatching said tool from each of said clamp assemblies and
retrieving said
tool to the water's surface. .Iaddend. .Iadd.17. A method as
recited in claim 16 in which said first subsea pipe comprises a
pipeline and said second subsea pipe comprises a manifold on said
subsea template. .Iaddend. .Iadd.18. A method as recited in claim
17 in which said spool piece contains maintainable equipment.
.Iaddend. .Iadd.19. A method as recited in claim 18 in which said
maintainable equipment comprises a hydraulically operable fail-safe
valve. .Iaddend. .Iadd.20. Apparatus for use in connecting and
disconnecting a spool piece to and from, respectively, spaced-apart
first and second subsea pipes comprising:
two clamp assemblies for clamping the ends of said spool piece to
the ends of said first and second subsea pipes;
a remotely operable pipe connecting-disconnecting tool
including:
guidance means engageable with said second subsea pipe;
1anding means engageable with said first subsea pipes;
means connecting said guidance means and said landing means for
moving said spool piece into engagement with said first subsea
pipe;
means for engaging one of said clamp assemblies for operating said
one clamp assembly to clamp said spool piece and said first subsea
pipe together; and
means for releasably latching said tool to each of said clamp
assemblies. .Iaddend. .Iadd.21. Apparatus as recited in claim 20 in
which said spool piece comprises maintainable equipment. .Iaddend.
.Iadd.22. Apparatus as recited in claim 21 in which said
maintainable equipment comprises a hydraulically operable fail-safe
valve. .Iaddend. .Iadd.23. Apparatus as recited in claim 22
including a hub formed on said second subsea pipe, said guidance
means including a yoke for engaging said second subsea pipe hub.
.Iaddend. .Iadd.24. Apparatus as recited in claim 23 including:
two spaced-apart adjustable plates for engaging said spool piece,
each of said plates containing guide means, wrench means, and motor
means for operating said wrench means;
guide sleeves arranged on said clamp assemblies to receive said
guide means; and
wrench heads arranged on said clamp assemblies, said wrench means
being engageable with said wrench heads. .Iaddend.
Description
BACKGROUND OF THE INVENTION
The present invention relates to the remote connection of subsea
flowlines and, in particular, to method and apparatus for
connecting subsea pipelines to a submerged structure without the
use of divers. More particularly, the invention concerns attaching
subsea pipelines to subsea manifolds employing a connecting tool
which is capable of aligning, clamping, testing and maintaining the
connections between the pipelines and the manifold.
SUMMARY OF THE INVENTION
The present invention provides improved method and apparatus for
connecting a spool piece hub, connected to the manifold of a subsea
structure or template, to a pipeline hub. In the method a remotely
operated pipeline connecting tool is lowered from a surface vessel
to the template and properly positioned over the pipeline and
manifold hubs. The connector tool is latched to the spool piece and
the spool piece hub and pipeline hub are drawn together by
hydraulic cylinders attached to sliding frames on the connecting
tool. The hubs are then clamped together and pressure tested.
To retrieve a spool piece for replacement the connecting tool is
lowered and latched onto the spool piece which is disconnected by
unclamping the spool piece hubs from the manifold and pipeline
hubs. The sliding frames on the connecting tool spread the manifold
and pipeline hubs and the connecting tool is locked to the spool
piece which is lifted from between the hubs and retrieved. All
connecting tool operations except the alignments are surface
controlled, hydraulic power fluid being supplied from a surface
vessel.
Prior to lowering the connecting tool a section of the pipeline
containing the pipeline hub and a trunnion assembly attached
thereto is lowered vertically to adjacent the spool piece hub. As
the pipeline hub and trunnion assembly are lowered additional
sections of pipe are connected to the initial pipeline section
attached to the trunnion assembly. Lowering the continues until the
trunnion assembly latches to the template. Additional sections of
pipe are laid out and during the laying operations the pipeline
pivots 90.degree. to the horizontal at the trunnion assembly which
places the pipeline hub in final position for connection to the
spool piece hub.
The apparatus for carrying out the method of the invention includes
a spool piece having one spool piece hub adjacent said pipeline hub
for connection thereto and the other hub thereof connected to a
manifold hub which connects to a template; clamp means arranged on
the spool piece hub for clamping the spool piece hub and pipeline
hub together; and a remotely operated connecting tool having
guidance frame means engageable with the manifold hub, landing
frame means engageable with the pipeline hub, means connecting the
guidance frame means and the landing frame means for moving the
spool piece hub into connection with the pipeline hub; means for
engaging the clamp means for operating the clamp means to clamp the
spool piece hub and pipeline hub together and means for releasably
locking the connector tool to the spool piece. In addition, conduit
means are provided on the clamp means for supplying fluid to the
connected hubs to test the connection and means are provided on the
connecting tool for connecting the conduit means to a source of
fluid. The spool piece may include a hydraulically operable valve,
the operation thereof being controlled from the template through
connections in the manifold and spool piece hubs.
Further, the apparatus includes two guide posts connected to
guidelines; a pipeline section having a pipeline hub; a trunnion
assembly attached to the pipeline section and containing guide
funnels and a latch for latching onto the template.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 2 are schematic views of a pipeline hub being
positioned on a subsea template in alignment with a spool piece hub
in accordance with the method of the invention;
FIG. 3 is a schematic view of a remote pipeline connecting tool
positioned on the pipeline and manifold hub assemblies for
connecting the spool piece hub to the pipeline hub;
FIG. 4 is a schematic view of the spool piece hub clamped to the
pipeline hub;
FIG. 5 is a schematic view illustrating recovery of the connecting
tool;
FIG. 6 is a side view which illustrates the apparatus for clamping
the spool piece hub to the pipeline and manifold hubs;
FIG. 7 is a view taken along lines 7--7 of FIG. 6;
FIG. 8 is a view illustrating details of the connecting tool;
FIG. 9 is a view taken along lines 9--9 of FIG. 8;
FIG. 10 is a view taken along lines 10--10 of FIG. 8;
FIG. 11 is a fragmentary view illustrating one of the wobble plate
assemblies positioned adjacent the spool piece hub;
FIG. 12 is a top view of the wobble plate assembly shown in FIG.
11;
FIG. 13 is a view taken along lines 13--13 of FIG. 12;
FIG. 14 is a view taken along lines 14--14 of FIG. 11; and
FIGS. 15 and 16 are fragmentary views illustrating operation of the
latch fingers.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 there is shown a subsea template 10 to which is latched a
trunnion assembly 11 by latches 13 having latch releasing arms 13A
and to which is pivotally attached by pins 11A a pipeline 14 with a
connection hub 15. Trunnion assembly 11 also includes a base member
12, guide funnels 12A and other suitable securing means as, for
example, tapered pins extending from base member 12 into holes in
template 10, not shown, to fix trunnion assembly 11 on template 10.
An isolation valve 16 is located on pipeline 14 adjacent trunnion
assembly 11 on which pipeline 14 and hub 15 pivot relative to base
member 12. Pipeline 14, hub 15 and trunnion assembly 11 are lowered
into position on template 10 by two guide posts 17 positioned on
template 10 and guide cables 18 connected to the guide posts. Base
member 12 is latched to template 10 by latch 13, as shown. A valve
spool piece 19 contains a valve 20 and a hub 21 to which hub 15 is
to be connected and a hub 22 which is connected to a hub 23 of a
manifold hub assembly 24 connected to manifold piping 24. Valve 20
is a balanced stem fail-safe valve such as described and claimed in
U.S. No. 3,933,338 by D. P. Herd et al. Hub assembly 24 is
supported by and shear pinned to a post 27 supporting cone end
support 26. Hubs 22 and 23 are clamped together by a clamp assembly
50 and hub 21 is provided with a clamp assembly 51 which is used to
clamp it to hub 15. Each clamp assembly is the type clamp connector
described and claimed in U.S. Pat. No. 3,843,168 by C. D. Morrill
et al. In FIG. 2 pipeline hub assembly 11 is shown pivoted into
horizontal and properly aligned with valve spool 19 for connection
of hubs 15 and 21.
Referring to FIG. 3 a remote pipeline connecting tool 30 is lowered
on drill pipe 31 from the water's surface guided by guide posts 17
and cables 18 and guide sleeves 17A on the connecting tool onto
trunnion assembly 11 and manifold hub assembly 24. Connecting tool
30 includes a support frame 32 which provides structural support
for the other components of the connecting tool. A valve operator
33 is supported on frame 32. A wobble plate assembly 34 includes
vertical plate assemblies 35 and 36 slidably mounted on guide rods
37 and 38 which are secured to frame 32. A pair of piston-cylinder
assemblies 39 connect plate 35 of wobble plate assembly 34 and a
guidance frame 40. As shown, guidance frame 40 is positioned
adjacent hub 23 of the manifold hub assembly 24. A landing frame
41, shown in landed position on trunnion assembly 11, is located
adjacent hub 15. A pair of piston-cylinder assemblies 42 connect
landing frame 41 and guidance frame 40. Guidance frame 40 is also
slidably mounted on guide rods 37 and 38 while landing frame 41 is
slidably mounted on guide rods 37. A pair of piston-cylinder
assemblies 43 connect landing frame 41 and support frame 32 as
shown. Connecting tool 30 in FIG. 3 is in position for moving hub
21 to hub 15.
In FIG. 4 hubs 15 and 21 are shown made up and clamped together by
clamp assembly 51 and valve actuator 33 is in position to open or
close isolation valve 16. Manifold piping 25 contains a loop, not
shown, that acts as a spring to allow manifold hub movement without
overstressing the piping.
In FIG. 5 connecting tool 30 is shown being retrieved to the
surface following successful testing of the made up connection.
FIG. 5 also illustrates lowering of connecting tool 30 into
position on trunnion assembly 11 and the manifold hub assembly 24
for removal of spool piece 19.
Referring now to FIGS. 6 and 7 in which the details of spool piece
19 and clamp assemblies 50 and 51 on hubs 21 and 22 are
illustrated. Clamp assemblies 50 and 51 each include a vertical
plate 52 bolted to each hub 21 and 22 by bolts 53. A pair of
horizontal plates 54 on each clamp assembly support a pair of guide
sleeves 55 and clamp operating rods 56 which are provided with hex
shaped wrench heads 57. Also supported on one of the horizontal
plates 54 is the male half of test hydraulic connector 58 which is
connected by a conduit 59 to a port, not shown, on each hub 21 and
22 between seals 60 and 61 (indicated on the contacting surface
face of hub 21). Clamp halves 62 are shown threaded onto rods 56.
The clamp assemblies are in closed position on hub 22 and in the
open position on hub 21. A semicircular saddle sleeve 66 is fixed
to the back of plate 52.
Plate 52 has an opening 63 at its upper end forming lug ears 64
which are shown engaged by latch fingers 65 (see FIG. 7).
Guidance frame 40, as seen in FIGS. 8 through 10, includes guide
yoke 40A, the lower tapered, wedge-shaped portion of which aids in
moving manifold hub assembly 24 into proper position with respect
to spool piece 19. Each plate assembly 35 and 36 includes a plate
73 and a wobble plate 74, the latter being pulled against plate 73
by tie rods 75. Guidance frame 40 is attached to sleeves 70 which
slide on guide rods 37 and 38. Plates 73 of wobble plate assembly
34 are attached to sleeves 71 which slide on guide rods 37 and 38.
Landing frame 41 is attached to sleeves 72 which slide on upper
guide rods 37. A plate 76 is movably mounted on a roller 77 which
is attached to each wobble plate 74. Attached to the underside of
each plate 76 are downwardly extending guide pins 78. Each plate 76
also has a pair of torque motors 79 attached to it.
In FIG. 11 it is seen that each motor 79 is attached to a wrench 80
which extends below plate 76 and is positioned to engage a hex head
57 of the clamp assemblies. Each wobble plate 74 sits on a
semicircular shoulder 81 attached to plate 73 by bolts 82. The
center portion 83 of the upper surface of each wobble plate 74 is
formed as a curved surface having a center point 84 which is also
the center point for the semicircular surface 91 on shoulder 81. A
roller 85 is mounted on plate 73 and bears against curved surface
83. A pair of centering springs 86 surround pins 87 which are
attached to the upper end of plate 74 and extend through spring
retainer boxes 88 which are attached to plate 73 by bolts 89. Each
of the two tie rods 75 extend through an enlarged opening 90 in
plate 73. The limited movement afforded by the mountings of plates
74 and 76 permits adjustments in aligning guide sleeves 55 with
guide pins 78 and hex heads 57 with wrenches 80. When the wobble
plates are lowered into position on valve spool 19 surfaces 91A
engage saddle sleeves 66. In that position of connecting tool 30
guide pins 78 are aligned in sleeves 55 and wrenches 80 engage
wrench heads 57.
Referring to FIGS. 12 through 16, in which details of the latch
assemblies are shown, latch pins 65 are mounted in openings 95 on a
rod 96 which is mounted for rotation in each wobble plate 74. A
piston-cylinder assembly 97 is pivotally connected at one end to
wobble plate 74, as at 98, and at the other end to link arm 99
which is also attached to rod 96. When shoulder 81 engages saddle
sleeve 66 (see FIG. 11) latch fingers 65 are in position within
opening 63 to be extended and engage underneath ears 64. Once so
extended, spring fingers 76 lock connecting tool 30 to spool piece
19.
In operation, after guide posts 17 and guidelines 18 are installed
at a prepared location on template 10 trunnion assembly 11, with
pipeline 14 and hub 15 attached, is lowered with guidelines 18
within the two guide funnels 12A of the trunnion assembly. As
trunnion assembly 11 is lowered additional sections of pipe are
joined to the original pipeline section. Addition of pipe sections
continues until guide funnels 12A slide over guide posts 17.
Lowering continues until latches 13 latch trunnion assembly 11 to
template 10. An additional sections of pipeline are laid out
pipeline section 14 is pivoted 90.degree. from vertical to
horizontal which places pipeline hub 15 in final position for
connection to spool piece hub 21.
Connecting tool 30 is then lowered with guidelines 18 within guide
sleeves 17A to guide posts 17 where initial alignment is achieved.
As lowering continues guidance yoke 40A of guidance frame 40
engages manifold hub assembly 24 between hub 23 and cone-shaped
support 26. The three points of alignment, the two guide posts and
the manifold hub correctly position connecting tool 30 over
pipeline hub 15 and spool piece hub 21. Lowering continues and the
weight of connecting tool 30 is landed on trunnion assembly 11 by
landing frame 41. The hydraulically powered landing frame 41 is
retracted by piston-cylinders 43 and the entire connecting tool 30
drops from its landing point into position for pipeline connection.
During the last downward movement wobble plate assembly 34 permits
final alignment of guide pins 78 and sleeves 55. Latch fingers 65
are activated to lock connecting tool 30 and spool piece 19
together. Spool piece hub 21 and pipeline hub 15 are drawn together
by hydraulic cylinder assemblies 42 attached to sliding guidance
and landing frames 40 and 41, respectively, of connecting tool 30.
Movement of manifold piping 25 toward pipeline hub 15 disconnects
the manifold piping 25 from post 27 by shearing the pins connecting
them. The female half of connector 58 on hydraulic connecting tool
30 is extended to connect with the male half of hydraulic connector
58 on clamp assembly 51, the seals between hubs 15 and 21 are then
tested for pressure integrity. A suitable hydraulic connector 58
may be that disclosed and claimed in U.S. Pat. No. 3,918,485 by R.
A. Weber et al. After a good pressure test and on command from the
surface connecting tool 30 opens manual isolation valve 16 and
releases latch fingers 65 from spool piece 19. The tool is
retrieved to the surface, guidelines are retrieved and the
connection is complete.
To retrieve a spool piece for replacement, connecting tool 30 is
lowered and latched onto the installed spool piece 19. Spool piece
19 is disconnected from the manifold and pipeline hubs by operation
of torque motors 79 to release clamp assemblies 50 and 51 and by
operation of piston-cylinder assemblies 39 and 43 to move guidance
frame 40 and landing frame 41 to spread the manifold and pipeline
hubs. The wobble plate assembly 34 is centered and spool piece 19
is lifted from between the hubs and connecting tool 30 is
retrieved.
In U.S. Pat. No. 3,775,986 entitled "Method and Apparatus of Making
Remote Pipeline Connections" a "pull-in" method to align subsea
pipelines is disclosed and claimed. The method of the present
invention for connecting the pipeline hub to the spool piece hub
may also be used with that "pull-in" method once the pipeline hub
and spool piece hub are properly positioned and aligned.
Spool piece 19 may be, as described, a valve spool or it may be a
pipe, control pod or any other maintainable component. Also, the
method for connecting the pipelines may be conducted from a
floating vessel or grounded platform. Further, instead of
guidelines to guide the trunnion assembly and connecting tool into
proper position other known guiding techniques, such as the
acoustic positioning technique, may be used. Other changes and
modifications may be made in the illustrative embodiments of the
invention shown and/or described herein without departing from the
scope of the invention as defined in the appended claims.
* * * * *