Note: Descriptions are shown in the official language in which they were submitted.
CA 02533725 2006-O1-23
APPARATUS AND METHOD FOR PERFORMING EARTH BOREHOLE
OPERATIONS
1
2 FIELD OF THE INVENTION
3 The invention relates to apparatus for performing earth borehole
4 operations such as drilling, and in particular to apparatus which can use
both
coiled tubing and jointed-pipe.
6
7 BACKGROUND OF THE INVENTION
8 The use of coiled tubing (CT) technology in oil and gas drilling and
9 servicing has become more and more common in the last few years. In CT
technology, a continuous pipe wound on a spool is straightened and pushed
11 down a well using a CT injector. CT technology can be used for both
drilling and
12 servicing.
13 The advantages offered by the use of CT technology, including economy
14 of time and cost are well known. As compared with jointed-pipe technology
wherein typically 30-45 foot straight sections of pipe are threadedly
connected
16 one section at a time while drilling the wellbore, CT technology allows the
17 continuous deployment of pipe while drilling the well, significantly
reducing the
18 frequency with which such drilling must be suspended to allow additional
19 sections of pipe to be connected. This results in less connection time, and
as a
result, an efficiency of both cost and time.
21 However, the adoption of CT technology in drilling has been less
22 widespread than originally anticipated as a result of certain problems
inherent in
23 using CT in a drilling application. For example, because CT tends to be
less
24 robust than jointed-pipe for surface-level drilling, it is often necessary
to drill a
surface hole using jointed-pipe, cement casing into the surface hole, and then
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CA 02533725 2006-O1-23
1 switch over to CT drilling. Additionally, when difficult formations such as
rock are
2 encountered down-hole, it may be necessary to switch from CT drilling to
jointed
3 pipe drilling until drilling through the formation is complete, and then
switch back
4 to CT drilling to continue drilling the well. Similarly, when it is
necessary to
perform drill stem testing or coring operations to assess conditions downhole,
it
6 may again be necessary to switch from CT drilling to jointed-pipe drilling
and
7 then back again. Finally, a switch back to jointed pipe operations may be
8 necessary to run casing into the drilled well. In short, in CT drilling
operations it
9 is generally necessary for customers and crew to switch back and forth
between
CT drilling rig and jointed-pipe conventional drilling rigs, a process which
results
11 in significant down-time as one rig is moved out of the way, and another
rig put
12 in place.
13 Another disadvantage of CT drilling is the time consuming process of
14 assembling a (bottom-hole-assembly (BHA) - the components at the end of the
CT for drilling, testing, well servicing, etc.), and connecting the BHA to the
end of
16 the CT. Presently, this step is performed manually through the use of
rotary
17 tables and make-up/breakout equipment. In some instances, top drives are
used
18 but the CT injector and the top drive must be moved out of each others way,
i.e.,
19 they cannot both be in line with the borehole. Not only does this process
result
in costly downtime, but it can also present safety hazards to the workers as
they
21 are required to manipulate heavy components manually.
22 In U.S. Publication 2004/0206551 there is disclosed a rig adapted to
23 perform earth borehole operations using both CT and/or jointed-pipes, the
CT
24 injector and a top drive being mounted on the same mast, the CT injector
being
selectively moveable between a first position wherein the CT injector is in
line
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CA 02533725 2006-O1-23
with the mast of the rig and hence the earth borehole and a second position
2 wherein the CT injector is out of line with the mast to allow operations
using the
3 top drive involving jointed pipe.
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CA 02533725 2006-O1-23
1 SUMMARY OF THE INVENTION
2 In one aspect, the present invention provides an apparatus for performing
3 earth borehole operations comprising a base or substructure, a mast mounted
4 on the base, a top drive mounted on the mast for longitudinal movement
therealong, the top drive having an opening therethrough, and a coiled tubing
6 injector mounted on the mast above the top drive such that coiled tubing
from
7 the tubing injector can pass through the opening in the top drive.
8 In another aspect, the present invention provides an apparatus for
9 connecting the tubing of a coiled tubing injector to a bottom hole assembly
comprising a base or substructure; a mast mounted on the base; a top drive
11 mounted on the mast for longitudinal movement therealong, the top drive
having
12 an opening therethrough; a coiled tubing injector mounted on the mast above
the
13 top drive such that coiled tubing from the coiled tubing injector can pass
through
14 the opening in the top drive; a rotary table mounted on the base, the
rotary table
being operable to engage and manipulate a first component of a bottom hole
16 assembly, the top drive being operable to engage and manipulate a second
17 component of a bottom hole assembly, the top drive and the rotary table
being
18 cooperatively operable to make up a complete bottom hole assembly, the
coiled
19 tubing injector being selectively operable to move coiled tubing through
the
opening in the top drive and into and out of engagement with the complete
21 bottom hole assembly.
22 In still another aspect of the present invention, there is provided a
method
23 of performing earth borehole operations comprising: providing a base;
providing
24 a mast mounted on the base; providing a top drive mounted on the mast for
longitudinal movement therealong, the top drive being operable to engage and
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CA 02533725 2006-O1-23
1 manipulate components used in earth borehole operations, the top drive
having
2 an opening therethrough; providing a coiled tubing injector mounted on the
mast
3 above the top drive such that coiled tubing from the injector can be passed
4 through the opening in the top drive; providing a rotary table mounted on
said
base; selectively using the top drive to engage and manipulate a components)
6 used in earth borehole operations while the coiled tubing injector is
substantially
7 inoperative; and selectively using the coiled tubing injector to inject
coiled tubing
8 into the earth borehole while the top drive is substantially inoperative,
the coiled
9 tubing passing through the opening in the top drive.
In another aspect, the present invention provides a method of performing
11 earth borehole operations comprising: providing a base; providing a mast
12 mounted on the base; providing a top drive mounted on the mast for
longitudinal
13 movement therealong, the top driving being operable to engage and
manipulate
14 a component used in earth borehole operations, the top driving having an
opening therethrough; providing a coiled tubing injector mounted on the mast
16 above the top drive such that coiled tubing from the injector can pass
through the
17 opening in the top drive; using the top drive to engage and manipulate a
18 component used in earth borehole operations; and using the coiled tubing
19 injector to inject coiled tubing into said component through said opening
in said
top drive.
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1 BRIEF DESCRIPTION OF THE DRAWINGS
2 Fig. 1 is a partial, side elevational view of an apparatus according to the
3 present invention.
4 Fig. 2 is a partial, side elevational view of a second embodiment of the
apparatus of the present invention.
6 Fig. 3 is a partial, side elevational view of the apparatus shown in Fig. 1,
7 wherein the top drive is manipulating a tubular component.
8 Fig. 3A is a view taken along the lines 3A-3A of Fig. 3.
9 Fig. 4 is a partial, side elevational view of another embodiment of the
apparatus of the present invention.
11 Fig. 5 is a partial, side elevational view of the apparatus of the present
12 invention shown in Fig. 4 with the coiled tubing injector in a position to
perform
13 earth borehole operations and shows, in phantom, positioning the mast of
the
14 apparatus at an angle to the horizontal to effect off-vertical earth
borehole
operations.
16 Fig. 6 is a side, partial elevational view showing a bottom hole assembly
17 being made up using the apparatus of the present invention.
18 Fig. 7 is a side, partial elevational view showing another embodiment of
19 the apparatus of the present invention wherein the hydraulic ram system is
used
as the lifting mechanism for the top drive.
21 Fig. 7A is a view taken along the lines 7A-7A of Fig. 7.
22 Fig. 8 is a partial, side elevational view of another embodiment of the
23 apparatus of the present invention showing the top drive positioned
directly
24 below the coiled tubing injector on a track system secured to the mast.
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1 Fig. 9 is a partial, side elevational view of the embodiment shown in Fig. 8
2 but with the top drive moved laterally on a spur track system such that the
top
3 drive is laterally displaced from the coiled tubing injector.
4 Fig. 10 shows a top, detailed view of a split block arrangement for
carrying the top drive.
6 Fig. 11 is an elevational view of a top drive-split block arrangement shown
7 in Fig. 10.
8 Fig. 12 is a top plan view, similar to Fig. 10 showing how the top drive can
9 be moved laterally relative to the mast.
Fig. 13 is an elevational view of the arrangement shown in Fig. 12.
11 Fig. 14 is a partial, side elevational view of another embodiment of the
12 apparatus of the present invention.
13 Fig. 15 is a rear elevational view of the embodiment shown in Fig. 14.
14 Fig. 16 is a view similar to Fig. 13 showing the coiled tubing injector
pivoted 90E from the position shown in Fig. 13.
16 Fig. 17 is a rear elevational view of the embodiment shown in Fig. 16.
17 Fig. 18 is a side elevational view of another embodiment of the apparatus
18 of the present invention.
19 Fig. 19 is a rear elevational view of the embodiment shown in Fig. 18.
Fig. 20 is a view similar to Fig. 18 but showing the coiled tubing injector
21 and the gooseneck being rotated 90E relative to the view shown in Fig. 18.
22 Fig. 21 is a rear elevational view of the embodiment shown in Fig. 20.
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1 DESCRIPTION OF THE PREFERRED EMBODIMENTS
2 Referring first to Fig. 1, the apparatus of the present invention is seen to
3 comprise a mast, shown generally as 10, and a base shown generally as 12.
4 Mast 10, as shown particularly with reference to Fig. 3A, is comprised of a
pair of
spaced elongate frame members 14 interconnected at the top by a crown 16.
6 Although not shown, mast 12 is pivotally connected to base 12 for reasons
7 described hereafter. However, it is not necessary that mast 10 be pivotally
8 connected to base 12, i.e., it could be fixedly attached, if desired. As
shown,
9 base 12 comprises a wheeled carrier or trailer 18 providing a generally
centrally
located platform 20, the wheeled carrier 18 having a tongue 22 which can be
11 attached to a motorized vehicle such that the trailer 18 can be moved from
one
12 location to another. It will be appreciated that the wheeled carrier 18 can
be self
13 propelled and even further that the base can comprise a stationary
structure as,
14 for example, a skid or the like which can be raised and placed on a trailer
or
other transport vehicle for movement to another site, if desired. It will also
be
16 appreciated that the apparatus of the present invention could be mounted on
an
17 offshore platform via a skid or other substructure on while the mast and
other
18 components are mounted. Wheeled trailer 18 also provides a second, rear
19 platform 26 on which is mounted a rotary table 24. Rear platform 22
provides a
work surface 26 for workers to manipulate various downhole components into
21 and out of the rotary table and to perform other normal operations in
conjunction
22 with earth borehole operations such as drilling, workover, servicing, etc.
23 Rotatably mounted on the platform 18 is a spool 28 upon which is wound
24 a length of coiled tubing 30. Spool 28 can be rotated in clockwise and
counterclockwise directions using a suitable drive assembly (not shown). Also
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CA 02533725 2006-O1-23
1 located on platform 18 is an engine 27 and a hydraulic tank 29 for storage
of
2 hydraulic fluid used in operating the various hydraulic components of the
3 apparatus, e.g., motors, hydraulic cylinders, etc. As is well known, most of
the
4 components of the apparatus can be operated hydraulically, electrically or,
in
some cases, pneumatically. The coiled tubing 30 extends up to a gooseneck or
6 guide 32 supported in a well-known manner. The gooseneck 32 is attached to a
7 coiled tubing injector 34 which, as shown in Fig. 3A, is positioned between
8 members 14 forming mast 10. As is well-known to those skilled in the art,
coiled
9 tubing injector 34 typically comprises a series of blocks, sprockets or like
grippers driven by endless chains or belts, shown in phantom as 39, and which
11 grab the coiled tubing 30 and force it downwardly in the direction of arrow
A
12 when it is being injected into a well and move it upwardly in the direction
of arrow
13 B when it is being removed from the well.
14 As shown in Figs. 1 and 3A, a top drive 36 is mounted on mast 10
between members 14 for longitudinal movement therealong in either the
16 direction of arrow A or arrow B. Typically, top drive 36 is mounted on a
track
17 system, indicated as 15, which is affixed to members 14. It will be
recognized,
18 however, that top drive 36 could be suspended in other fashions other than
the
19 track system 15 such that it could be longitudinally moved along mast 10.
Top
drive 36 is moved longitudinally along mast 10 by a hoisting system comprised
of
21 a winch or draw works mounted on platform 18 and one or more cables 40
which
22 run through a crown block sheave assembly 16a located at the top of mast
10.
23 The cables 40 pass through or by coiled tubing injector 34 and are attached
to
24 top drive 36 in a well-known manner whereby draw works 38 can selectively
raise top drive 36 upwardly along mast 10 or lower top drive 36 downwardly
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CA 02533725 2006-O1-23
1 along mast 10, i.e., in the directions of arrows A and B, respectively. In
the
2 embodiment shown in Fig. 1, the top drive serves as an elevator for the
coiled
3 tubing injector 34, in that movement of the coiled tubing injector 34
longitudinally
4 along the mast 10 is effected by movement of the top drive 36. In this
regard, as
noted, the cables 40 run through or alongside coiled tubing injector 34 and
are
6 attached to the top drive 36 in the well-known manner. It will be understood
7 however that, while more complicated, coiled tubing injector 34 could be
moved
8 independently along mast 10 by a separate draw works or winch. However, the
9 apparatus of the present invention is vastly simplified by using the top
drive 36
as an elevator to effect longitudinal movement of coiled tubing injector 34.
11 As seen in Fig. 1, top drive 36 has an opening 37 extending longitudinally
12 therethrough for a purpose to be described hereafter. While the opening 37
has
13 been described as extending longitudinally through the top drive 36, it is
14 conceivable that a top drive unit could be designed such that the opening
was
not through the top drive but rather was an opening in the form of a slot on
the
16 side of the top drive. Obviously, such a top drive would be more
complicated in
17 construction and might have to accommodate lateral movement such that when
18 the top drive was being used it was aligned with the vertical axis of the
borehole,
19 but when the tubing injector was being used, the tubing issuing therefrom
would
also be aligned with the vertical axis of the borehole. Accordingly, the
phrases
21 "longitudinally therethrough", "therethrough", or "through" with respect to
the
22 opening in the top drive is intended to include slots or other formations
in the top
23 drive which permit the coiled tubing injector to be positioned above the
top drive
24 and the coiled tubing maintained in line with the vertical axis of the
wellbore. A
suitable top drive for use in the apparatus of the present invention is a
Foremost
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CA 02533725 2006-O1-23
1 Model F-100T. The Foremost Model F-100T is a hydraulic top drive system and
2 is commercially available. As in the case with other top drive systems, the
Model
3 F-100T is provided with hydraulically actuated bails to assist in picking up
or
4 laying down tubulars and includes a hydraulically actuated tong assembly
mounted on the top drive to assist in breakout/make-up of the drill string or
other
6 tubular downhole strings.
7 It will be appreciated that when, as in the embodiment shown in Fig. 1, top
8 drive 36 is serving as an elevator for coiled tubing injector 34, provision
could be
9 made to have a platform, cradle or the like upon which coiled tubing
injector 34
would rest, the platform in turn resting on top drive 36. In any event, it
will be
11 appreciated that there are a variety of ways in which the coiled tubing
injector 34
12 can be positioned above top drive 36, such that top drive 36 can serve as
an
13 elevator for top drive 34. For example, while as shown in Fig. 1 coiled
tubing
14 injector 34 and top drive 36 are basically adjacent one another, it is
contemplated that some axial spacing could be accommodated, if necessary,
16 consistent with having enough longitudinal length along mast 10 for top
drive 36
17 to act independently when necessary. Such a situation would occur, for
18 example, when top drive 36 was being used to drill a surface borehole, run
19 casing, etc. In any event, it will be appreciated that with coiled tubing
injector 34
positioned above top drive 36, and with top drive 36 having an opening 37
21 extending longitudinally therethrough, coiled tubing 30 from coiled tubing
injector
22 34 can be passed through top drive 36 in which event top drive 36 would be
23 basically inoperative save for its function as serving as an elevator for
coiled
24 tubing injector 34.
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1 Turning now to Fig. 2, there is shown another embodiment of the present
2 invention, wherein the coiled tubing injector 34 is mounted on the crown of
the
3 mast 10 such that it is not longitudinally movable along the mast 10, but is
still
4 above top drive 36 such that, as in the case of the embodiment shown in Fig.
1,
coiled tubing 30 from injector 34 passes through the opening 37 in top drive
36.
6 The present invention provides a universal rig which can selectively
7 handle and run different types of pipe, coiled tubing, and other earth
borehole
8 equipment thereby eliminating the need for two rigs - one rig to use a top
drive in
9 the conventional manner and a separate coiled tubing injector unit to
perform
coiled tubing operations. Thus, in the embodiments shown in Figs. 1 and 2, the
11 coiled tubing injector 34 is being used to manipulate coiled tubing 30, the
coiled
12 tubing 30 passing through the top drive 36, the top drive 36 being
basically in an
13 inoperative position vis-a-vis manipulating tubular components, components
of
14 bottom hole assemblies or the like. However, and as noted above, in the
embodiment of Fig. 1, top drive 36 does serve the purpose of being an elevator
16 for coiled tubing injector 34.
17 Turning now to Fig. 3, there is shown an embodiment of the present
18 invention wherein the coiled tubing injector 34 is basically in an
inoperative
19 position while the top drive 36 is being operated to manipulate tubular
components. In the embodiment shown in Fig. 3, the coiled tubing injector 34
is
21 moved to the crown 16 of the mast 10 and is held in that position by a
latching or
22 locking mechanism as, for example, one or more pins 43 (see Fig. 3A) which
are
23 operatively mounted in mast 10 and which can be selectively operated,
24 electrically, hydraulically or in any other suitable fashion, to engage
coiled tubing
injector 34 or a cradle therefor and hold it in that position. It will also be
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CA 02533725 2006-O1-23
1 understood that a plurality of such latching or locking mechanisms can be
2 spaced longitudinally along mast 10 such that coiled tubing injector 34 can
be
3 held at a variety of desired, longitudinally spaced locations along mast 10.
It will
4 also be appreciated that provision could be made to use a screw mechanism
extending longitudinally along members 14 which could selectively engage or
6 disengage injector 34 to continuously or incrementally move coiled tubing
7 injector 34 along mast 10 rather than having longitudinally spaced latching
8 mechanisms such as the use of pins 43. In any event, with coiled tubing
injector
9 34 temporarily locked in the position shown in Fig. 3, i.e., at crown 16,
the top
drive 36 can now perform operations typically performed by a top drive such
as,
11 for example, manipulating a tubular component such as casing 42 brought in
12 through the V-door 44 as is common in typical oilfield operations. Although
not
13 shown, it will be appreciated that the apparatus of the present invention
would be
14 provided with elevators and other components normally used to manipulate
downhole components, e.g., pipe, as for example, to grip the pipe or other
16 downhole component and move it to a position where it could be engaged and
17 subsequently manipulated by the top drive. Thus, using the apparatus of the
18 present invention in the manner depicted in Fig. 3, the tubing injector 34
would
19 be inoperative while top drive 36 would be operative. This ability to
selectively
use the top drive and the injector independently of one another is clearly
21 advantageous in terms of saving cost and time.
22 With reference now to Fig. 4, there is shown a slightly different
23 embodiment wherein the draw works 38 is mounted on the mast 10, the cables
24 40 running through the crown block 16a in the crown 16 and down to the top
drive 36. It will be appreciated that in cases, such as the embodiment shown
in
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CA 02533725 2006-O1-23
1 Fig. 4, wherein the draw works 38 is mounted on the mast, the draw works
could
2 be removably mounted, carried on a trolley, hingedly attached or the like,
such
3 that, for transportation purposes, the draw works could basically be moved
to a
4 position that it did not extend above the mast when the mast was lowered to
the
horizontal, transportation position. As shown in Fig. 4, extending from coiled
6 tubing injector 34, is a telescoping lubricator 44, lubricator 44
facilitating
7 connection or disconnection of coiled tubing 30 with a bottom hole assembly.
As
8 is well known to those skilled in the art, lubricator 44 can be extended or
9 contracted using a lubricator winch (not shown).
Referring now to Fig. 5, there is shown still another, modified embodiment
11 of the apparatus shown in Fig. 1 wherein the draw works 38, as in the case
of
12 the embodiment shown in Fig. 4, is mounted on the mast 10. In the
embodiment
13 shown in Fig. 5, the top drive 36 and the injector 34 have been moved to
the
14 lowermost position, i.e., adjacent rotary table 24, and in this position,
top drive 36
would be essentially inoperative and coiled tubing injector 34 would be
operative
16 to perform downhole operations such as drilling, workovers, etc.
Additionally,
17 and as can be seen, mast 10 can be pivoted relative to the base 12 by a
pivoting
18 assembly (not shown) to a position depicted in phantom in Fig. 5. Thus, it
can
19 be seen that the mast 10 can be lowered off vertical to operate at any
operating
angle between the horizontal and vertical to permit off vertical drilling. It
would
21 also be understood that in cases where off angle well operations were being
22 performed, reorientation of the rotary table and other component would have
to
23 be accommodated. Additionally using a pivoting connection between the mast
24 10 and the base 12 allows the mast 10 to be lowered to a substantially
horizontal
position for purposes of moving the apparatus to another location if base 12
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CA 02533725 2006-O1-23
1 comprises a wheeled carrier which is either self-propelled or can be pulled
by a
2 motorized vehicle, a skid or the like, etc.
3 As noted above, the apparatus of the present invention is universal in the
4 sense that the same rig carries a coiled tubing injector to manipulate
coiled
tubing and a top drive to manipulate jointed pipe or other downhole
components,
6 the injector and the top drive being selectively, independently operable to
7 perform their customary functions. Additionally, the universal nature of the
8 apparatus of the present invention is attested to by the fact that when the
top
9 drive is being used to manipulate a downhole component, e.g., a string of
pipe,
such as casing, tubing, drill pipe, etc., the coiled tubing injector can be
11 simultaneously used to inject coiled tubing through the top drive into the
string of
12 pipe to perform an operation as, for example, freeing the pipe string if it
is stuck
13 or to some other downhole operation.
14 The present invention also provides an efficient apparatus to
cooperatively use the coiled tubing injector and the top drive. In this regard
and
16 referring to Fig. 6, the top drive 36 is shown in a position displaced
axially up
17 from the rotary table 24, the injector being positioned at the crown as
shown in
18 Fig. 3. In the embodiment shown in Fig. 6, the rotary table 24 is
suspending a
19 downhole motor 50 on the end of which is connected to a drill bit 52. As
can be
seen, the threaded box end 54 of the downhole motor 50 (or a component
21 attached to the downhole motor 50), is in a position to receive the
threaded pin
22 56 of a second downhole component 58 which can be a part of a bottom hole
23 assembly or alternatively, a conventional tubular member. To connect pin 56
24 with box 54, top drive 36 is lowered until pin 56 is received in box 54. At
this
point, with the rotary table 24 holding the downhole motor 50 fixed against
either
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CA 02533725 2006-O1-23
1 rotation or longitudinal movement, top drive 36 can be rotated to thread pin
56
2 into box 54. Alternatively, it will be understood that top drive 36 could be
used to
3 hold component 58 against rotation while it was slowly being lowered and the
4 rotary table 24 could be used to rotate the downhole motor 50 which again
would
cause threaded engagement between pin 56 and box 54. As noted, in the
6 embodiment shown in Fig. 6, component 58 could be part of a string of pipe
7 wherein a plurality of joints of pipe are successively connected together,
the
8 portion of the pipe string suspended in the rotary table 24 being released
and
9 lowered as each successive joint of pipe is connected whereby eventually the
entire string is lowered into the borehole. Fig. 6 also depicts a method of
making
11 up and connecting a complete bottom hole assembly to the end of the coiled
12 tubing from the coiled tubing injector 34. Thus with the assembly shown in
Fig.
13 6, once a complete bottom hole assembly, e.g., drill bit, downhole motor,
drill
14 collars, logging equipment, sensors, etc., is made up, the end of the
coiled
tubing and the uppermost member of the complete bottom hole assembly could
16 be operatively engaged using intergaging latching mechanisms whereby the
17 coiled tubing could be latched into the uppermost member of the complete
18 bottom hole assembly and, when the bottom hole assembly is retrieved
19 unlatched, if desired.
Referring now to Figs. 7 and 7A, there is shown an embodiment of the
21 present invention wherein, as an alternative, telescoping hydraulic
cylinder
22 systems are used to move the top drive longitudinally along the mast. The
23 apparatus shown in Figs. 7 and 7A might be utilized when the mast 10 was
24 unusually long, e.g., on an offshore platform and in a situation where the
top
drive 36 was manipulating longer strings of jointed pipe that would result in
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CA 02533725 2006-O1-23
1 greater loading that might make a draw works lifting system such as shown in
2 the embodiments described above, impractical or at least require a larger
winch,
3 more and heavier cables, etc. As can be seen from Fig. 7, the system
depicted
4 in Figs. 7 and 7A has no draw works. Additionally, the base 12 has support
legs
60 located generally under platform 36 to support the extra weight occasioned
by
6 the hydraulic cylinder system employed and any additional loading from the
7 mast, pipe being handled, etc. It would be appreciated that the leg 60 could
be
8 selectively extended and retracted as desired. The hydraulic cylinder
systems
9 shown generally as 62 can be made in a four-stage cylinder design comprised
of
cylinders 64, 66, 68 and 70, as which can be seen, are telescopically received
11 into one another such that when all the hydraulic cylinders are in their
lower most
12 position, they are all received in lower cylinder 64. It is well known to
those
13 skilled in the art, that the cylinder systems would be operated using
suitable
14 pumps, hoses, accumulators (are not shown) well known to those skilled in
the
art. The hydraulic cylinder systems 62 are mounted on a platform 72 formed on
16 base 12. It will be understood that with the use of the hydraulic cylinders
and the
17 increased weight, and if the base 12 was part of a wheeled carrier, as
described
18 above, the various portions of the base 12, particularly platform 72 would
be built
19 to accommodate the additional weight and the downward force exerted on the
base 12 when the cylinder systems were in a lifting position such as shown in
21 Fig. 7. As a practical matter, the apparatus shown in Figs. 7 and 7A is
more
22 ideally suited to use on a base or sub-structure such as on an offshore
platform
23 that can easily accommodate heavy loads or downward forces. However, for
24 purposes only of depicting the use of a hydraulic cylinder systems) as a
lifting or
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CA 02533725 2006-O1-23
1 hoisting device for the top drive 36, the hydraulic cylinder system 62 has
been
2 shown as mounted on a wheeled carrier.
3 As can be seen particularly with reference to Fig. 7A, there could be two
4 of such hydraulic cylinder systems 62, one each positioned adjacent,
generally
on the inside, of members 14 forming mast 10. Referring then to Fig. 7, the
6 uppermost cylinders 70 are connected to plates 80 that in turn are generally
7 releasably connected to top drive 36. As shown, plates 80 on top drive 36
are
8 connected, via a nut and bolt arrangement or some other selectively
releasable
9 mechanism, to a flange 82 connected to coiled tubing unit 34. In this
configuration, movement of the hydraulic cylinder systems 62 would effect
11 movement of both the coiled tubing unit 34 and the top drive 36. However,
if the
12 nut and bolt combinations 81 were removed, top drive 36 could now be moved
13 independently of coiled tubing injector 34 by the hydraulic cylinder
systems 62
14 and, for example, coil tubing unit 34 could be latched or locked to the
uppermost
portion of the mast 10 below the crown 16 as, for example, by latching pins 43
16 such as shown in Fig. 3a.
17 As noted above, the system of the present invention positions the coiled
18 tubing injector in the mast above the top drive such that coiled tubing
issuing
19 from the coiled tubing injector passes through the top drive. As further
noted
above, the coiled tubing need not move directly through any opening in the top
21 drive but can move in slots or other openings along the side of the top
drive. It is
22 also contemplated that the top drive, albeit normally positioned below the
coiled
23 tubing injector, could be moved to one side or another in a lateral or
transverse
24 direction relative to the mast such that the coiled tubing injector
remained in line
with the wellbore while the top drive was out of alignment with the wellbore.
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CA 02533725 2006-O1-23
1 Thus, the coiled tubing injector and the top drive could be temporarily in a
side-
2 by-side arrangement. This arrangement is particularly useful in relatively
small
3 rigs using relatively large diameter coiled tubing, e.g., 3". It will be
understood,
4 as described above, that normally a lubricator (see Fig. 4) will be employed
when coiled tubing injector is connected to a bottom hole assembly. Referring
6 then to Figs. 8 and 9, there is shown one embodiment of the present
invention
7 wherein the coiled tubing injector can be releasably, fixedly positioned at
a
8 desired point along the mast and the top drive parked or moved laterally
relative
9 to the coiled tubing injector such that coiled tubing issuing from the
coiled tubing
injector passes alongside the top drive into the earth borehole. Each of frame
11 members 14 of mast 10 is provided with a mast track 100 upon which coiled
12 tubing injector 39 and top drive 36 travel longitudinally therealong. Each
of mast
13 tracks 100 has operatively connected thereto a spur track or rail 102 which
14 extends transversely from mast tracks 100 to platform 26 or at least some
distance laterally displaced from mast tracks 100. As shown in Fig. 8, top
drive
16 36 is in the position acting as an elevator for coiled tubing injector 39
carried on
17 top drive 36, the combination of the coiled tubing injector 39 and top
drive 36
18 being positioned generally half way along the frame members 14 forming mast
19 10. As was described above, top drive 36 is free to move longitudinally
along
mast tracks 100 substantially from rotary table 24 to a desired upper position
21 when coiled tubing injector 39 is positioned and releasably fixed in mast
10
22 proximate crown 16.
23 Referring now to Fig. 9, coiled tubing injector 39 is shown as being
24 releasably, fixedly held in mast 10 in a manner described above, while top
drive
36 is now positioned in the lower portion of mast 10 but laterally displaced
from
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CA 02533725 2006-O1-23
1 mast 10, coiled tubing injector 39 and the axis 106 of the wellbore. To
2 accomplish this, coiled tubing injector 39 is releasably fixed in mast 10 at
the
3 location shown in Fig. 9. Top drive 36, as described, can move downwardly to
a
4 point 107 where spur tracks 102 operatively intersect mast tracks 100. At
this
point, a switching mechanism 104 is activated to divert a trolley or the like
on
6 which top drive 36 is sitting onto spur tracks 102 such that top drive 36
now
7 moves downwardly but tranversely to mast tracks 100 and can then be parked
or
8 located at a position where it is out of alignment with the wellbore axis
106. As
9 shown, top drive 36 has been moved relatively close to work surface 26 but
it is
apparent that it could be positioned higher from the position shown in Fig. 9,
11 indeed even at least partially in the framework of mast 10, and still
remain out of
12 alignment with the axis 106 of the wellbore. In any event, once the top
drive 36
13 is moved laterally relative to coiled tubing injector 39, coiled tubing
injector 39
14 can then inject coiled tubing 30 through rotary table 34 and into the
wellbore, the
coiled tubing passing alongside top drive 36. It will also be appreciated that
in
16 the event coiled tubing injector 39 is provided with a separate hoisting
17 mechanism as previously described, it could be moved along mast 10
18 independently of any movement of top drive 36. In any event, top drive 36
still
19 serves as an elevator for coiled tubing injector 39 which can be positioned
at a
desired location in the mast 10 first, following which the top drive, if
desired, can
21 be moved into a laterally displaced position as shown in Fig. 9. The terms
22 "operatively connected," "operatively intersect" or similar term with
respect to the
23 spur tracks 102 and mast tracks 100 is intended to mean that the two track
24 systems are interrelated to the extent that the top drive 36 can be
switched from
mast tracks 100 to spur tracks 102 or vice versa.
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CA 02533725 2006-O1-23
1 Switching mechanism 104 can be any one of well known switching
2 mechanisms used in track conveying systems to selectively switch a trolley
or
3 similar conveying device moving along a first track system to a second track
4 system. Such switching systems can be mechanical, electromechanical,
pneumatic, etc. It will also be appreciated that such switching mechanisms can
6 be activated manually or automatically such that when, in this case, top
drive 36
7 reaches a certain position, i.e., at the juncture or intersection of spur
tracks 102
8 and mast tracks 100, the switching system has been set in an automatic mode
to
9 move the top drive from mast tracks 100 to spur tracks 102.
It is well known in the art that top drives used in oil and gas drilling and
11 well servicing operations are commonly carried by a so-called integrated
split
12 block arrangement. In a split block arrangement, a frame having laterally
spaced
13 side members is provided with one or more sheaves on each of the spaced
side
14 members, each of the sheaves being connected by cables to a suitable crown
block. The use of these split block arrangements reduces stack-up as is
16 common in simple traveling block assemblies. Such a split block arrangement
is
17 ideally suited for use in the present invention to carry the top drive, the
coiled
18 tubing injector being positioned on a platform, cradle or the like which
would rest
19 on the top drive. In this manner, the split block assembly essentially
forming part
of the top drive, as described above, would act as an elevator for the coiled
21 tubing injector. Typical of split block arrangements used in conjunction
with top
22 drives is the T75/T100 series of top drives manufactured and sold by TESCO
23 Corporation as can be seen at www.tescocorp.com.
24 Referring now to Figs. 10-13, there is shown a split block assembly for
use in carrying the top drive used in the present invention. Frame members 14
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CA 02533725 2006-O1-23
1 of mast 10 are provided with longitudinally extending tracks 108 and 110. A
2 generally rectangular frame F shown as 110 comprises a first side frame
3 member 112, a second, laterally spaced side frame member 114, a first cross
4 frame member 16 and a second, laterally spaced cross frame member 118,
members 112, 114, 116 and 118 forming a generally rectangular opening in
6 frame F. Pivotally attached to frame members 118 and 116 is a bail 120. Bail
7 120 is also pivotally attached to top drive 36 as shown at 122. A piston-
cylinder
8 assembly 124 has one end of the cylinder pivotally attached as at 125 to
frame
9 member 118, the pivot point 125 being laterally displaced toward side member
112 relative to the pivot point 121. Reciprocally extending out of the
cylinder of
11 piston-cylinder assembly 124 is a piston rod 126 which has one end
pivotally
12 attached at 122 to bail 120.
13 Side member 112 has attached thereto sheaves 130 and 132 while side
14 member 110 has attached thereto sheaves 134 and 136. Cables 138, 140, 142
and 146 extend from sheaves 130, 132, 134 and 136, respectively, up to a
16 crown block assembly (not shown) as is well known to those skilled in the
art.
17 Thus, by movement of the cables 138-146, frame F can be moved
longitudinally
18 along tracks 108 and 110 and hence longitudinally along the mast 10 formed
by
19 frame members 14. To this end, roller assemblies 160 and 162 are attached
to
side frame member 112, while roller assemblies 164 and 166 are attached to
21 side frame 110. As shown, roller assemblies 160 and 162 engage track 108
22 while roller assemblies 164 and 166 engage track 109.
23 As shown in Figs. 10 and 11, top drive 36 is suspended below frame F so
24 as to be positioned generally centrally between side frame members 112 and
114, i.e., in a position generally in line with the wellbore axis 106.
_22_
CA 02533725 2006-O1-23
1 Referring now to Figs. 12 and 13, the top drive 36 is shown as being
2 displaced laterally off of the axis of the wellbore 106. To accomplish this,
3 hydraulic piston-cylinder assembly 124 is activated to retract piston 126
which
4 results in bail 120 pivoting around pivot point 121 moving top drive 36
toward
track 108. Piston-cylinder assembly 124 can be hydraulic, pneumatic and it
will
6 be appreciated that any number of mechanisms can be used to move bail 120
7 and hence top drive 36 between the positions shown in Figs. 11 and 13, i.e.,
8 from a position where top drive 36 is generally over center of the axis 106
of the
9 wellbore to a position, as shown in Fig. 13, where it is moved laterally
with
respect to the axis 106. While the use of only one piston-cylinder assembly
124
11 is shown, as a practical matter two such assemblies would be used, one
being
12 attached to cross member 118 as shown, the other being attached to cross
13 member 116. It will be apparent that piston-cylinder assembly 124 can be
14 attached to frame F on the side nearest track 109 such that top drive 36
would
now be moved to the left of wellbore axis 106 as viewed in Fig. 13. The
16 arrangement shown in Figs. 11 and 13 is as seen from the V-door side of the
17 drilling rig (see Fig. 3). Although perhaps somewhat more complicated, an
18 arrangement similar to that shown in Figs. 11-13 could be used to move the
top
19 drive laterally either towards the V-door or towards the trailer upon which
spool
28 is mounted.
21 Referring now to Figs. 14-17, there is shown an embodiment of the
22 present invention wherein the coiled tubing injector can be moved to the
top of
23 the mast and pivoted at least 90E so as to provide more vertical working
space
24 in the mast when the top drive is in use. The apparatus, shown generally as
200, comprises a mast shown generally as 202 which as seen in Fig. 15 is
-23-
CA 02533725 2006-O1-23
1 comprised of a pair of spaced, elongate frame members 204 and 206
2 interconnected at the top by a crown 208 carrying a crown block assembly as
3 described above and as is well known in the art. Preferably, mast 202 is
4 pivotally connected to a base 210, e.g., in the form of a wheeled trailer,
such that
mast 202 can be pivoted to a generally horizontal position for transportation
6 purposes. Mounted on wheeled trailer 210 is a reel 212 of coiled tubing from
7 which coiled tubing 214 can be played out. Coiled tubing 214 passes through
a
8 guide or gooseneck 216 and then into coiled tubing injector 218.
9 As seen particularly in Figs. 14 and 15, top drive 220 is located generally
midway of mast 202, coiled tubing 214 being injected via coiled tubing
injector
11 218 through a rotary table shown generally as 222, into a wellhead, tubing
214
12 passing through top drive 220 as described above.
13 Coiled tubing injector 218 is mounted on a carrier frame shown generally
14 as 224, carrier frame 224 comprising a pair of pillow blocks 226 and 228
which
are operatively connected to frame members 204 and 206, respectively. Thus,
16 as in the other embodiments described above, coiled tubing injector 218 by
17 means of frame 224 can move longitudinally along mast 202 on suitable
tracks
18 or the like mounted to the frame members 204, 206. Coiled tubing injector
218
19 is secured to or rotatably mounted on a shaft 230, one end of which is
received
in pillow block 226, the other end being received in pillow block 228. In the
case
21 where coiled tubing injector 218 is fixedly secured to shaft 230, shaft 230
would
22 be rotatably journaled in pillow blocks 226 and 228, suitable bearings
being
23 provided as is known to those skilled in the art. Alternatively, if coiled
tubing
24 injector 218 is rotatably mounted on shaft 230, then shaft 230 could be
fixedly
secured in pillow blocks 226 and 228. In either event, coiled tubing injector
218
-24-
CA 02533725 2006-O1-23
1 is pivotally secured to frame 224. In the embodiment shown, coiled tubing
2 injector 218 is fixedly secured to shaft 230.
3 A pair of pistons/cylinder assemblies 232, 234, which can be hydraulic,
4 are interconnected between coiled tubing injector 218 and pillow blocks 226
and
228, respectively. As can be seen, with respect to piston/cylinder assembly
232,
6 piston rod 235 is pivotally connected at 236 by a clevis or other suitable
7 connector to coiled tubing injector 218. The other end of the
piston/cylinder
8 assembly 232 is likewise pivotally connected as at 237 to pillow block 226
or for
9 that matter any other portion of carrier frame 224 which is not rotatable or
pivotable relative to mast 202. For example, if coiled tubing injector 218 was
11 rotatably mounted on shaft 230 such that shaft 230 was fixedly secured in
pillow
12 blocks 226 and 228, then the piston/cylinder assemblies could be secured to
13 shaft 230. As can be seen in Fig. 14, piston cylinder assemblies 232 and
234
14 are off-center with respect to the long axis of coiled tubing injector 218.
Accordingly, if piston rod 235, shown in its fully extended position in Figs.
14 and
16 15, is now retracted, there will be a vector of force generally in the
direction of
17 arrow A which will tend to pivot coiled tubing injector 218 around an axis
passing
18 through shaft 230. The end result is depicted in Figs. 16 and 17 wherein
coiled
19 tubing injector 218 has been pivoted such that it is now substantially
perpendicular to mast 202, i.e., to elongate frame members 204, 206. As can be
21 seen in Figs. 16 and 17, with piston cylinder assemblies 232, 234
retracted,
22 coiled tubing injector 218 has been moved 90E from a position where the
coiled
23 tubing injector 218 and hence coiled tubing 214 passing therethrough is
24 substantially in line with rotary table 222 and hence the wellhead to a
position, as
-25-
CA 02533725 2006-O1-23
1 shown in Figs. 16 and 17, wherein the coiled tubing injector 218 is
substantially
2 perpendicular to an axis passing through rotary table 222.
3 As can also be seen from Figs. 16 and 17, by pivoting coiled tubing
4 injector 218 to the position shown, top drive 220 now has additional
vertical
space above the rotary table 222. This allows mast 202 to be more compact in
6 terms of its height. In this regard it will be appreciated that, depending
upon the
7 size of coiled tubing injector 218, the arrangement shown in Figs. 14-17
permits
8 another 2 to 18 feet of vertical head space in mast 202 allowing top drive
220 to
9 move to a greater height in mast 202 than would be possible if coiled tubing
injector 218 was confined to the position shown in Figs. 14 and 15. Ideally,
the
11 pivot axis of coiled tubing injector 218 is as far up as practical, i.e.,
towards the
12 top of coiled tubing injector 218, so as to achieve the maximum vertical
head
13 space in mast 202.
14 Suitable piston/cylinder assemblies useful in the embodiment described in
Figs. 14-17 and methods of connecting the same to suitable sources of
hydraulic
16 or pneumatic power are well known to those skilled in the art and need not
be
17 described in any detail here.
18 Referring now to Figs. 18-20, there is shown a variation of the
19 embodiment of the invention depicted in Figs. 14-17, wherein the coiled
tubing
injector can be moved from a position where the coiled tubing injector is in
line
21 with the rotary table/wellhead to a position where the coiled tubing
injector is out
22 of line substantially 90E, with e.g., the wellhead. In the embodiment shown
in
23 Figs. 18-21, the reel 212 of coiled tubing in conjunction with the coiled
tubing 214
24 is used to rotate coiled tubing injector 218 from the position shown in
Figs. 18 to
the position shown in Fig. 20. In this regard, coiled tubing injector 218, as
in the
-26-
CA 02533725 2006-O1-23
1 case of the embodiment shown in Figs. 14-17, is pivotally mounted on a frame
2 224 which in turn is longitudinally movable along the length of mast 202. In
the
3 position shown in Figs. 18 and 19, coiled tubing injector 218 is in
operation,
4 coiled tubing 214 being played off of reel 212 through top drive 220 and
into the
wellhead through rotary table 222. In this situation, and as will be
appreciated,
6 reel 212 is rotating in a clockwise direction as indicated by arrow B.
7 Turning now to Figs. 20 and 21, once it is desired to rotate coiled tubing
8 injector 218 from a position in line with the wellhead, i.e., through rotary
table
9 222, to the position shown in Figs. 20 and 21, the coiled tubing 214 which
is held
or can be held by any convenient means in coiled tubing injector 218, is now
11 reeled back onto reel 212, reel 212 now rotating in a counterclockwise
direction
12 as indicated by arrow C. In this manner, the coiled tubing injector 218,
secured
13 to shaft 230 which in turn is rotatably journaled in journal boxes 226 and
228, will
14 now be caused to rotate around the axis passing through shaft 230 to the
position shown in Figs. 20 and 21. At this point, top drive 220 can then be
16 moved to the desired location in mast 220, to manipulate a piece of jointed
pipe
17 240 or other tubular member.
18 It will be appreciated that in the embodiment shown in Figs. 14-17, the
19 piston cylinder assemblies 232, 234 can be used to lock coiled tubing
injector
into the position shown in Figs. 16 and 17 by methods well know to those
skilled
21 in the art. In the case of the embodiments shown in Figs. 18-21, a locking
pin,
22 as described above, or other latching mechanism can be used to hold coiled
23 tubing injector 218 in the position shown in Figs. 16 and 17. Indeed, it
will be
24 appreciated that any number of techniques and apparatuses can be used to
maintain coiled tubing injector in the pivoted positions shown in Figs. 16 and
20.
-27-
CA 02533725 2006-O1-23
1 While two methods of pivoting coil tubing injector 218 have been
2 described, it will be apparent to those skilled in the art that other
devices such as
3 rotary actuators, gearing arrangements, winch systems, etc., can be
employed.
4 The "carrier frame" on which coiled tubing injector 218 is pivotally
mounted can comprise any assemblage of components which alone or together
6 with other operating mechanisms will (a) allow coiled tubing injector 218 to
be
7 pivoted, and (b) allow coiled tubing injector 218 to be moved longitudinally
along
8 the mast.
9 As thus seen from the description above, the apparatus of the present
invention can be used in a manner wherein only the top drive is operative, the
11 coiled tubing injector being positioned, for example, at a point above the
top
12 drive, e.g., at the top of the mast adjacent the crown and being
inoperative.
13 Alternatively, the top drive can be moved to a lowered position on the
mast, e.g.,
14 at or near the rotary table with the coiled tubing injector being carried
by the top
drive, the coiled tubing injector continuously injecting tubing into the earth
16 borehole to perform a variety of operations. In this latter mode, the top
drive is
17 essentially inoperative save for the fact that it carries the coiled tubing
injector
18 and can still serve as an elevator for the coiled tubing injector. In any
event all in
19 embodiments, the coiled tubing injector, the top drive and the rotary table
are on
axes that are substantially coincident or can be made coincident with the
21 wellbore.
22 The word "base" or "substructure" as used herein is intended to mean any
23 structure, be it portable or fixed, whether on land or offshore, to which
the mast
24 can be fixedly, pivotally or removably attached, which will support the
mast and
the attendant equipment used in the apparatus of the present invention,
-28-
CA 02533725 2006-O1-23
1 including the coiled tubing spool, attendant motors, winches or draw works,
and
2 any other equipment commonly used either with (a) coiled tubing injectors,
or (b)
3 top drives.
4 The apparatus of the present invention can be used to accomplish
numerous different earth borehole operations. In the case of employing the
6 coiled tubing injector, the apparatus can be used to drill using downhole
mud
7 motors, such drilling being both directional and straight hole.
Additionally, coiled
8 tubing can be used in various completion operations such as fracturing;
9 acidizing; cleanouts; fishing operations; using coiled tubing as a velocity
string,
etc. The coiled tubing can also be run as production tubing. With respect to
11 typical top drive operations, conventional drilling can be done, casing can
be run,
12 and completion operations as described above with respect of coiled tubing
can
13 also be accomplished. Additionally, the top drive can be used to run
14 conventional production tubing.
In general, the apparatus of the present invention permits every earth
16 borehole operation that can be done in oil and gas well drilling using
either a top
17 drive or a coiled tubing unit.
18 A distinct advantage of the apparatus of the present invention when
19 compared with prior art, so-called universal systems such as disclosed in
U.S.
Publication 2004/0206551, is the ability to perform simultaneous operations
with
21 both the coiled tubing injector and the top drive. In this regard, in the
prior art
22 universal systems it is necessary, when using the top drive, to move the
coiled
23 tubing injector laterally out of alignment from the borehole and vice
versa. With
24 the apparatus of the present invention, since the coiled tubing injector
remains
positioned in line with the top drive and the borehole, in the event, for
example,
-29-
CA 02533725 2006-O1-23
1 that operations with the top drive are being performed, e.g., running
casing, and
2 the casing sticks, using the apparatus of the present invention, coiled
tubing can
3 be run down through the top drive into the casing to assist in freeing the
casing.
4 It will be apparent that other situations can occur where it would be
necessary to
quickly inject coiled tubing down through the top drive and through a tubular
6 string or other downhole component being manipulated by the top drive to
effect
7 some downhole operation. This, of course, cannot be accomplished with the
8 prior art, so-called universal systems since, as noted, only one of the top
drive or
9 the coiled tubing injector can be positioned in alignment with the wellbore
at any
given time.
11 In the above description, the word "mounted" has been used with respect
12 to the interrelationship between various components of the apparatus as,
for
13 example, the relation of the mast to the top drive and/or the coiled tubing
14 injector. It is to be understood that, as used herein, the word "mounted",
or
variants thereof, in addition to its usual meaning, is intended to include
meanings
16 such as "positioned", "positioned on", "carried by", "carried on",
"carried", "sitting
17 on", "resting on", or any other similar term. In other words, the word
"mounted",
18 or variants thereof, is not necessarily limited to meaning "affixed",
"affixed to",
19 "attached to", "attached", "secured to" or other words or phrases carrying
a
similar meaning. Thus, for example, references in the description above to the
21 coiled tubing injector being "mounted on the mast" are intended to include
22 situations wherein the coiled tubing injector is positioned adjacent to the
mast or
23 positioned relative to the mast, all with the goal of achieving a scenario
wherein
24 the coiled tubing injector, when injecting coiled tubing, is above the top
drive
-30-
CA 02533725 2006-O1-23
1 such that coiled tubing from the tubing injector can pass through the
opening in
2 the top drive from a position above the top drive.
3 It will be understood, that the present invention is not limited to the use
in
4 oilfield operations but can be used in water well drilling, mining
operations, in
drilling injection wells, etc. Also, as noted above, the apparatus of the
present
6 invention is not limited to land earth borehole operations but can be used,
as
7 well, on offshore drilling and production platforms.
8 The foregoing description and examples illustrate selected embodiments
9 of the present invention. In light thereof, variations and modifications
will be
suggested to one skilled in the art, all of which are in the spirit and
purview of
11 this invention.
-31 -
