Note: Descriptions are shown in the official language in which they were submitted.
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DISCONNECTABLE AND RECONNECTABLE WET CONNECTOR
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to downhole electrical connections made up in a wet
environment. More particularly, the invention relates to downhole sealed
connectors
which self clean upon makeup to avoid contamination in the connection.
Prior Art
Downhole power/signal wire connection/disconnection has always been a
problem for the industry. More specifically, because the downhole environment
is
extremely hostile to electric connection (salt water, fresh water, acids,
etc.), it has
traditionally been thought that a reliable "wet connection" could not be
effected. Prior
art systems have attempted to create wet connection that employ in the
downhole
environment but have met with only limited reliability. The prior art
connectors are
quite small and require an unlikely degree of precision when the connection is
to be
made, for example, 5000 feet below the surface. Therefore, although these
connectors
are reasonably capable of providing a good electrical connection at the
surface in
modern wellbore systems, they fail to solve the need for connection of an
uphole
string to a downhole string far below the surface. Such connections are
required for
the plurality of tools incorporated which require power and instructions.
SUMMARY OF THE INVENTION
The above-discussed and other drawbacks and deficiencies of the prior art are
overcome or alleviated by the wet connector/disconnector embodiments of the
invention.
All of the embodiments of the invention avoid the need to stab-in a small
connector. The stabbing-in of the tubing itself is all that is necessary to
make up the
connection. This is a substantial benefit to the art in view of the growing
use of
CA 02358288 2004-08-18
2
electrically activated downhole tools. The wet connect/disconnect ensures
reliability of such systems due to an increase in the likelihood of connection
and a
reduction in the care needed to effect the connection.
Most of the embodiments disclosed herein employ an insulator that protects a
conductor installed with the downhole equipment. The insulator may be rubber,
plastic, metal, a grease, etc. with the joining principal being to maintain
the conductor
in a very clean condition. Additionally, some of the embodiments further
include a
hydraulic fluid wash to ensure the conductor does not become contaminated with
the
insulator is pierced or otherwise removed by the string/connector being
stabbed in.
Generally, the conductor on the stab-in tool is also protected by one or more
of the
insulators noted above.
Other embodiments do not employ conductor insulators on the downhole
string but rely upon a cleansing action of the uphole string upon stab-in to
remove
any debris or oxidation that may have accumulated on the downhole conductors.
With each of the embodiments disclosed herein, the process of stabbing in
causes certain events to occur which lead to secure reliable connections.
In addition to the ability to wet connect, some of the embodiments herein
allow for a wet disconnect and reconnect which is advantageous for situations
requiring such activity. In one embodiment, a portion f the uphole string is
left
connected to the downhole string. This leaves the connection made during
stabbing-in
undisturbed. Rather a piece of the uphole section, which itself provides a new
insulated conductor (or not insulated) for a subsequent stab-in procedure, is
left
behind. Thus, in the event that the uphole section of string needs to be
pulled, a
reconnection may be made at a later time in the same manner as the original
conductor
mating. In order to be able of a section downhole, a switch section must also
be
employed to break the connection with the upper string. The switch section
must
break the connection in a sealed environment to prevent a short circuit upon
reconnecting the uphole string.
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3
Accordingly, in one aspect of the present invention there is provided a
conductor connection device for makeup and break in a wet downhole environment
comprising:
a first section connectable to implements intended to be located farther
downhole than said first section when said device is installed in a wellbore;
at least one first section conductor associated with said first section;
a first connector in operable communication with each said at least one first
section conductor, each said first connector being maintained in a clean
condition or
being cleanable while in the wet environment by operation of the connection
device;
a second section connectable to implements intended to be located farther
uphole than said second section when said second section is installed in a
wellbore;
at least one second section conductor associated with said second section;
a third section operably connected to said second section;
at least one third section conductor associated with said third section, said
at
least one third section conductor being operably connected to said at least
one second
section conductor;
a third connector in operable communication with said at least one third
section conductor, said third connector being maintained in a clean condition
or being
cleanable while in the wet environment by operation of the connection device,
said
third connector being connectable to said first connector by operating said
connection
device, said third section being optionally separable while in the wet
environment
from said second section after said connection device is operated to break the
electrical connection between said implements located farther uphole and said
implements located farther downhole; and
a fourth connector in operable communication with said at least one third
conductor, said fourth connector being maintained in a clean condition or
being
cleanable while in the wet environment by operation of a subsequent connection
device configured to make electrical connection with said fourth connector.
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3a
According to another aspect of the present invention there is provided a
method for creating a conductive connection in a wet downhole environment
while
providing for disconnection and reconnection in the wet environment
comprising:
installing a first section connectable to implements located farther downhole
than an intended location of said first section, said first section having at
least one
first section conductor associated therewith and a connector operably
connected to
said at least one first section conductor;
installing a second section connectable to implements located farther uphole
than an intended location of said second section, said second section having
at least
one second section conductor associated therewith, said second section further
including a third section having at least one third section conductor
associated
therewith and a third connector operably connected at one end to said at least
one
third section conductor and a fourth connector operably connected at the other
end of
said at least one third section conductor; and
engaging said third section and said first section creating an electrical
connection between said first connector and said third connector while in the
wet
environment.
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3b
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will now be described more fully with
reference to the accompanying drawings, in which:
FIGURE 1 is a schematic elevation view of the concept of the invention;
FIGURE 2 is an enlarged view of a specific embodiment for circumscribed
portion A of FIGURE 1;
FIGURE 3 is an enlarged view of an alternate specific embodiment for
circumscribed portion A;
FIGURES 4A and 4B are a top and bottom portion of an alternate connection
apparatus for the circumscribed portion A in FIGURE 1 in a non-connected
position;
FIGURES SA and SB are a top and bottom portion of the embodiment of
FIGURE 4A and 4B in a connected position;
FIGURES 6 A and 6B are disconnected and connected views, respectively of
another alternate embodiment for the circumscribed section A in FIGURE l;
FIGURE 7 is another alternate embodiment for the circumscribed section A
in FIGURE 1;
FIGURES 8A and 8B are disconnected and connected views respectively of
another alternate embodiment for the circumscribed section A in FIGURE 1;
FIGURES 9A and 9B are an embodiment of the circumscribed area B in
FIGURE 1,
FIGURES l0A-C are various positions of an alternate embodiment of the
circumscribed section B in FIGURE 1;
FIGURES 11-13 are an elongated quarter-section view of the tool of this
embodiment of the invention to illustrate the disassembled condition;
FIGURES 14-17 are together awelongated quarter-section view of another
connector tool of the invention;
FIGURE 18 is a cross section view of the portion of the invention illustrated
in FIGURE 11 taken along section line 15-15; and
FIGURE 19 is a cross section view of the portion of the invention illustrated
in FIGURE 12 taken along section line 16-16.
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DETAILED DESCRIPTION OF SEVERAL PREFERRED EMBODIMENTS
Refernng to FIGURE 1, a schematic illustration provides an understanding of
the disclosure in its broadest sense without details on the specific
mechanisms of
operable models. It will be understood that many different embodiments are
possible
which are capable of being employed to effect the desired results aforesaid.
Each of
the FIGURES following FIGURE 1 illustrate small sections of FIGURE 1 to teach
one of skill in the art a way of connecting or disconnecting the circumscribed
areas A
or B of FIGURE 1. It is also to be appreciated that in many instances in this
specification reference is made to "electrical" or "electrically"; this
terminology is for
exemplary purposes only and it is intended that the reader understand that
other
conductors- such as fiber optic conductors and light could also be employed.
The broad concept begins with the manufacture of a connection device capable
of being installed in a wellbore in various ways and connected to various
other
devices. Figure 1 illustrates schematically, a connection device in a
wellbore. In
1 S Figure 1, a lower (first) section of wellbore has been completed with (or
from the
stand point of manufacture is completable with) a tool string 12 having one or
more
electrically actuated or controlled tools which may have sensors, etc. This
lower
section 12 is for any number of reasons, which are known to those of skill in
the art,
isolated from an upper (second) section of tubing string 14. For this reason,
providing
an electrical connection between the upper section 14 and lower section 12 is
needed.
As noted above, such connections have been difficult in the prior art because
of the
harsh downhole environment. This disclosure therefore, provides a system for
such
connection by excluding the downhole fluids from the section 12 conductors (or
cleaning them) and ensuring that contaminants do not become introduced thereto
during connection. Lower section 12 includes associated wires (or fibers) 16
(one or
more) which are connected at the factory to conductor pads (connector) 18.
Conductor pads 18 are generally embedded in the tubing and will include a seal
thereover to prevent contamination. Lower section 12 is run in the hole or
otherwise
disposed downhole in this condition and will remain in a sealed condition with
respect
to the pads 18 until an upper section 14 is run in the hole to make a
connection with
pads 18. Exactly how the pads are connected is discussed hereunder.
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It will be appreciated in the FIGURE 1 illustration that another distinct part
is
illustrated between lower section 12 and upper section 14. This is reconnect
(third)
section 20. Reconnect section 20 is optional to operability of the system with
respect
to the original connection. It should be appreciated from a review of FIGURE 1
that
the features of lower section 12 are duplicated in reconnect section 20. Thus,
it will
be understood that upper section 14 might only contain features sufficient to
mate
with lower section 12 and avoid reconnect section 20. In a preferred
embodiment,
however, reconnect section 20 is included. Section 20 provides features that
substitute for the second connector with respect to connection to the first
connector.
The section allows for the original connection to remain intact if the upper
section 14
is pulled for some reason. This prevents contamination of the conductor pads
18. By
way of explanation, once the conductor pads 18 are freed from the insulation
that
protects them (in this type of embodiment) by the action of stabbing in the
uphole
section, they are left unprotected from the elements. With the upper section
attached,
1 S no environmental fluid can contact the pads. If the upper section is
pulled however,
the conductors would be subject to attack by wellbore fluids. Reconnecting to
these
conductor pads would be unlikely to succeed. For this reason reconnect section
20 is
employed. Continuing now with the discussion of section 20, the section
includes a
disconnect for the wires in the upper section 14 so that the termination of
electrical
continuity caused by the pulling of section 14 does not allow a "live"
connection to
contact downhole fluids. This is important to prevent damage to downhole
electrical
tools or destruction of the system upon reconnect. The disconnection area is
schematically illustrated by circumscribed area B in FIGURE 1.
Reconnect section 20 is solely provided to create a stacked system capability.
More specifically, reconnect section 20 is connected at the factory to the
upper section
14 with a shearable or otherwise releasable connection to upper section 14. In
the
event upper section 14 must be removed from the hole, it leaves in its wake,
reconnect
section 20 which includes new sealed connector pads 18' and wires 24 which
connect
to the original stab in connectors 26. A subsequent upper section may then be
stabbed
into the reconnect section with the same reliability as the original
connection the
concept of the reconnect section may be employed over and over again as many
times
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as a disconnect and reconnect are necessary. The reconnect sections simply
continue
to stack up as strings are pulled and reconnected.
Turning now to specific mechanisms, circumscribed area A is discussed first
and is directed to several embodiments for creating a clean electrical
connection with
S reliability and high confidence. In these FIGURES, only the connection
mechanism is
illustrated. It is to be understood that the mechanism is part of section 14
or section
20 as desired. Following the discussion of area A, circumscribed area B is
discussed.
Area B is directed to embodiments for breaking the connection with the wires
22 of
section 14 when that section is pulled.
Referring to FIGURE 2, a cover 30 illustrated herein as plastic, but which may
be rubber or metallic, is positioned in a sealed relationship over conductor
18. Thus,
while this portion of lower section 12 is exposed to wellbore fluid, the
conductor 18 is
protected. The connection mechanism which is shown in place after run in but
before
actuation, includes a bore 34, preferably filled with hydraulic fluid 30 (or
similar). A
wedge 38 is provided in the bore 34 which is driven like a piston preferably
by
pressure from a proximate or remote source into contact with electrical
connector 40
connected with wire 44 from the upper section. Electrical connector 40
includes a
ramped surface 46 and a punch 48. Ramped surface 46 is complementary to wedge
38
and connector 40 is urged thereby toward seal material 42. Continued urging of
connector 40 results in piercing of seal 42. Upon the piercing of seal 42,
fluid 36
escapes from bore 34, flooding the area between seal 42 and seal 30. The
flooding
action displaces wellbore fluids and provides a clean dielectric embodiment in
which
the connection can be made. Continued urging of connector 40 causes the punch
48
to pierce seal 30 and come into electrical contact with conductor pad 18. It
should be
noted that fluid 36 may preferably be dielectric fluid or a dielectric grease.
The grease
is preferred due to its viscosity and therefore its tendency to remain around
the
connection.
Referring now to FIGURE 3, an alternate connection mechanism is illustrated.
This mechanism, it will be appreciated, is very similar to the embodiment of
FIGURE
2 and merely adds seals 50 which are preferably chevron type seals. For
clarity, the
other parts of this embodiment, though slightly different in some respects are
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numbered identically to FIGURE 2. The FIGURE 3 embodiment provides additional,
if redundant, assurance of the continued cleanliness of the connection area.
Seals 50
do not allow fluid to pass in either direction whereas seal 50' allows fluid
to pass in
only the "out" direction relative to the space defined by seals S0, SO'. Thus,
the
movement of the cleansing fluid 36, which in this embodiment is preferably
hydraulic
fluid, will sweep all remnants of well fluids out of the connection space and
provide a
clean connection area.
Refernng to FIGURES 4A, 4B and SA, SB another alternate embodiment of
the invention is illustrated. Because of the relative complexity of the
embodiment, it
is illustrated in both a nonconnected and cormected form, FIGURES 4A, 4B and
SA,
SB, respectively.
Refernng first to FIGURES 4A and 4B, lower section 12 will provide a
reference. This embodiment functions by sliding the upper section, or
reconnect
section if so equipped, relative to the lower section 12' against spring
biased rings
which cover the conductor pads. Lower section 12 of this embodiment includes
spring 60 based upon land 62 which biases ring 64 to a position where it
covers pad
18. Section 12' also includes preferably two o-rings 66, which seal against
ring 64,
and a wiper 68. Section 14', or 20' if so equipped, includes spring 70 which
rests on
spring stop 72 and biases ring 74 to a position covering conductor pad 76.
Ring 74 is
sealed over conductor pad 76 by o-rings 78 mounted in ring 74. Conductor pad
76 is
preferably spring loaded by springs 80 so that it will be biased against
conductor pad
18 when so positioned.
An astute reader, skilled in the art, will recognize that there is a volume 82
that
likely is contaminated, and that this volume might be problematic to the
connection
even in view of wiper 68. To eliminate this possibility, the inventors hereof
have
provided an enclosed hydraulic fluid reservoir 84 which opens via a rupture
disk 86 to
volume 82. A piston 88 is provided which is operably connected to reservoir 84
and
positioned such that the "sliding past" of this embodiment as discussed above
causes
piston 88 to move into reservoir 84 increasing pressure therein until rupture
disk 86
fails and hydraulic fluid is expelled into volume 82. The hydraulic fluid will
displace
any wellbore fluids in the volume 82 and render the area clean.
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In operation, piston 88 lands on ring 64 and expels the hydraulic fluid as
discussed. Once piston 88 is fully depressed into the bore of reservoir 84,
shoulder 90
begins to urge ring 64 downhole by over coming the bias of spring 60. Next,
ring 74
comes into contact with shoulder 92 of section 12' and is urged uphole by
overcoming
the spring 72 with downhole movement of the upper section or the reconnect
section
as the case may be.
Conductor pad 76 is uncovered at the time it reaches wiper 68 and is wiped
clean to remove any oxidation that may have developed over time. Continued
downhole movement of the uphole section aligns conductor pads 18 and 76 and
the
connection is complete.
FIGURE SA and SB illustrate this embodiment in the connected condition to
promote understanding of the invention.
Referring now to FIGURES 6A and 6B, yet another alternative mechanism for
the circumscribed area A in FIGURE 1 is illustrated. The lower section of the
drawing is an alternative configuration of section 12 and thus is identified
as 12". The
conductive pads also differ in appearance and thus are designated 18". The
upper
section 14" (it should be understood that the upper section of the FIGURE
could also
be the reconnect section) includes a fluid-filled chamber 100 having an
exhaust port
102 sealed by a one-way valve 103 and a rupture disk 104. The chamber 100 is
sealed
at its other end by seal 106. In a preferred arrangement several o-ring seals
are also
supplied and are identified by 108. Focusing on the portion of upper section
14" that
defines chamber 100, it will be noted that two wipers 110 are provided. One
wiper
would be effective but two is preferred for redundancy and better cleaning.
Contact
pads 112 are provided in this area and are protected by fluid 114 in chamber
100.
In use, nose 116 of section 12" is urged into seal 106 ultimately rupturing
the
seal. since o-rings 108 will prevent fluid 114 from escaping around nose 116,
the
fluid instead becomes pressurized. As the pressure in chamber 100 increases,
burst
disk 104 ruptures and fluid 114 is conveyed through the valve 103 to the
tubing LD.
Since valve 103 will not permit fluid to pass in the other direction, the
connection area
in the chamber 100 will remain clean. Continued movement of nose 116 into
chamber 100 brings pads 18" into wiping contact with wipers 110 where the
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conductor pads 18" are cleaned of any oxides that have formed thereon. The
pads 18"
then align with pads 112 and the connection is made as illustrated in FIGURE
6B.
FIGURE 7 is another alternative embodiment relating to circumscribed area A
is illustrated. In this embodiment the upper section provides a connector 120
which is
composed of a low temperature melt metal (obviously, melting temperature must
be
above well temperature at projected depth). The metal connector 120 is
positioned
adjacent conductor pad 18 and includes a coil 122 proximate thereto, the
proximity
being sufficient to melt the connector 120. As in previous embodiments, seals
134,
132 are provided and a reservoir 128 includes fluid 130 actuated by a piston
126 to
flush the contact area. In this embodiment a surface actuated current or a
downhole
actuated current melt the connector 120 which then flows into electrical
contact with
conductor pad 18.
In another alternate embodiment for circumscribed Section A, referring to
FIGURES 8A and 8B lower section 12 includes two conductor pads 18. The upper
section of the drawing which again can be the equivalent of section 14 or
section 20 in
FIGURE 1 depending upon whether a reconnect option after a pull-out is to be
provided, provides a nose 130 with several seals 132 of preferably the chevron
type.
Attached to nose 130 by a release mechanism, preferably a shear pin 134, is
connector
wedge 136 which houses a piercing conductor pad 138 in fluid 140 under seal
142.
Upon downward movement of the upper section of the drawing (14 or 20) a spring
144 is urged against a ring 146 to move the same downhole until it contacts
landing
148 of counter wedge 150. Further downward movement causes counter wedge 150
to move downhole behind connector wedge 136 to cause conductor pads 138 to
pierce
cover 142 and come into contact with conductor pads 18 to complete the
circuit.
As discussed above, in the event upper section 14 is removed from the hole,
the connections must be broken to prevent a short circuit. This is, for
illustrative
purposes, at the area marked B on FIGURE 1. It is important to note that just
stretching the connectors to break leaves them exposed to wellbore fluids and
invites
short circuit. Therefore the inventors hereof have provided the following two
embodiments of disconnects. It is to be understood, however, that other
mechanisms
for providing such a disconnect are clearly within the scope of the invention.
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Turning now to FIGURES 9A and 9B, the first disconnect embodiment is
illustrated in the connected position and the disconnected position. The
disconnect
itself comprises a connector pad 162 disposed a top an insulator 160 in a
recess 172 in
section 12. The recess 172 is sealed by cover 168 which may be of a plurality
of
distinct materials so long as they either deflect or allow a sealed sliding of
the pins
166 therethrough. In the case of deflection, the pins 166 need not slide
through cover
168 (the non-sliding arrangement being illustrated herein).
As one can readily ascertain from the drawings, pins 166 provide a base for
pads 164, the pins extending to outside cover 168 and into connection with
plate 170.
The disconnect is connected together in the factory and appears as illustrated
in
FIGURE 9A. When a disconnect is desired, pulling the tool causes the switch to
be in
the condition illustrated in FIGURE 9B wherein the electrical connection is
broken
and the ends of the downhole wires are protected within recess 172 and cover
168. It
will be apparent to one of skill in the art that if upper portion 174 of the
drawings is to
be removed altogether the disconnect will have to shear at a point above the
cover
168. Alternatively, the portion 174 could simply be a ring which remains
downhole.
Referring now to FIGURES 10A, l OB and lOC a second disconnect
embodiment is illustrated. This disconnect is intended to work in much the
same way
that the embodiment of FIGURES 9A 9B works and thus only the distinctions are
discussed here. Contact bar 180 is connected to an uphole piece of the pipe
and
supports actuator pin 182 and contact pins 184. Pin 182 includes a wedge 186
which
is angled sufficiently to actuate slide 190 through slide pitch 188. Actuation
of slide
190 moves it (to the right in the drawing) to align ports 192 with contact
receptacles
194 wherein contact pads 196 are disposed and connected to wires 198. Once
alignment as described is complete, pins 184 may come into electrical contact
with
pads 196 (pads 196 are insulated from the metallic tool by insulation 200).
The length of the pins 182 and 184 is important to the operation of the
invention. Upon disconnecting, it is required that the slide 190 be closed
(under bias
of spring 204) prior to pins 184 pulling free from membrane 202. By so
requiring, the
breach in the seal of membrane 202 due to the pins 184 being extended
therethrough
is not able to allow contamination into receptacles 194. Obviously it is
intended that
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slide 190 make sealing contact with the surrounding area. This embodiment is
made
up in the factory preferably but is also useable in the field because of the
ability of pin
182 to actuate slide 190 in a time frame where the pins 184 will protectively
be in
membrane 202.
In yet another embodiment of the invention wherein conductors are aligned
and connected. Referring initially to FIGURES 11-13 a more schematic view of
the
invention is illustrated. The view does not contain all of the parts of the
invention and
thus is intended to convey the locations and orientation of the connectors.
Tool 10
breaks down to a top half (comprising FIGURES 11 and 12) and a bottom half
comprising FIGURE 13. When the halves are separated as illustrated in FIGURES
11-13, lower seal adapters 212 (twelve of them on the embodiment shown
although
more or fewer could be employed) are visible on bottom half (FIGURE 13) and
the
complementary upper seal adapters 214 (an equal number to the number of lower
seal
adapters 212). Upper seal adapters 214 preferably include a pair of o-rings
270 to
fluid tightly seal the lower seal adapters. Upper seal adapters 214 are
connected to the
uphole environment via conduits 218 while at the other end of the connection,
lower
seal adapters 12 are connected to the downhole environment via conduit 20. The
conduits 218 and 220 preferably contain fiber optic conductors. The mating
ends of
the conductors are cleaned by preferably a hydraulic fluid which may be
applied in a
number of ways including adaptations of the embodiments preferably does not
include
threads between the alignment profile and end connections.
Although the top and bottom portions of the tool are run in the hole together
(assembled at the surface), an alignment profile 222 is provided in the tool
to align the
top and bottom halves in the event that they are separated. Therefore,
refernng
directly to FIGURES 12 and 13, a profile 224 is a raised area in a
predetermined
orientation on the anchor sub 226. The profile 224 mates with a complementary
profile 228 in bottom half (FIGURE 13). The orientation profiles ensure that
the
lower seal adapters 212 will align and mate with upper seal adapters 214
reliably.
Turning now to the internal components of this embodiment of the invention,
referring to FIGURES 14-19, and beginning at the uphole end of the tool, a box
thread
230 is provided to attach the tool to a work string (not shown). The box
thread 230 is
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cut in body 232 which extends downhole to threadedly mate with anchor sub 234
at
thread 236. Body 232 supports, near the uphole end thereof, disc spring
retainer cap
238 which is threaded to the O.D. of body 232 at thread 240. Cap 238 is
further
preferably anchored by cap screw 242. Cap 238 functions to retain preferably a
plurality of disc springs (belleville washers) 244. Springs 244 absorb
longitudinal
movement of upper and lower seal adapters. Moreover, the washers keep the
upper
and lower seal adaptors positively shouldered internally which is important
for pump
down, replaceable optic fiber installation and other installations. Disc
springs 244 are
maintained in position at the downhole end by retainer sub 246. Sub 246 is
annular
and is threaded to disc spring adjustment sub 248 at thread 250.
Downhole of attachment sub 248 and radially outwardly of body 232 is upper
connector 252. Upper connector 252 houses upper seal adapters 214 at the
downhole
end thereof and a line connector assembly 254 which preferably comprises a
pair of
ferrules and a jam nut (not individually shown). The connector 252 is retained
in
position on body 232 by shear screw 256 and shoulder screw 258. These latter
screws
are best viewed in FIGURE 18. A plurality of bores 260 are provided in upper
connector 252 to receive conduit 218. Lower connector 262 (FIGURES 15 and 19)
is
disposed downhole of upper connector 252 and houses lower seal adapter 212,
bore
264 for conduit 220 and a control line connector 260 which comprises a pair of
ferrules and a jam nut (not individually shown). It should be noted that
FIGURE 15
provides a cross section view of the tool which shows the upper and lower seal
adapters that were explained previously herein. It should also be noted that
upper seal
adapter 214 includes two sets of o-rings 268 and 270. Rings 268 seal upper
seal
adapter 214 to upper connector 252 while rings 270 seal the lower seal adapter
212
into the upper seal adapter 214 when it is so engaged. Lower adapter 212 may
be for
conventional conductors or fiber optic conductors. FIGURE 19 illustrates three
of
four (212a) in conventional form and one (212b) in fiber optic form .
Bridging FIGURES 15 and 16 is sleeve 272 which covers the components of
the snap in/snap out feature of the invention (components discussed
hereunder).
Sleeve 272 is connected to seal housing 274 which includes locking dogs 276.
Seal
housing is also threaded at 278 for a body lock ring 280. The lock ring 280 is
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rotationally arrested by roll pin 236. Seal housing 274 is sealed to anchor
sub 234 by
seal stack 281.
Radially outwardly of seal housing 274 (FIGURES 16 and 17) are housing 282
and control line sub 284. Housing 282 includes several seals 286, several
screws 288
and a dog receiving profile 290.
Radially inwardly of sleeve 272 (FIGURE 16) is the snap in/snap out assembly
mentioned above. The assembly includes, beginning from the uphole end, a shear
ring
retainer 292 which is connected to the anchor sub 234 by shear ring 294. Shear
ring
retainer 292 is also connected to support ring 298 through set screws 296 and
thread
300. Support ring 298 supports set down sleeve 302 and is in contact with body
lock
housing 306. Body lock ring housing 306 is connected to body lock ring 304
conventionally and including a set screw 308 to arrest rotational movement.
Body
lock ring housing 306 is also threadedly connected to set down sleeve 302 by
thread
310. Body lock ring housing 306 cannot move up or downhole because of shear
screw 312 which engages anchor sub 234. Body lock ring housing 306 is
connected
to latch 314 by parting ring 316 which is a ring having holding profiles 318
to retain
the body lock ring housing 306 to latch 314 until a predetermined tensile load
is
placed thereon which breaks the parting ring 316.
In operation and after running in the hole, a pressure line 243 (FIGURE 16)
pressurizes a piston area 318 sealed by seals 86. Upon reaching a
predetermined
pressure, shear screw 288 shears and allows housing 282 to move downhole thus
locating recess 290 over locking dogs 276 allowing them to move radially
outwardly
to disengage from anchor sub 234. Once anchor sub 234 is disengaged from the
dogs
276 it will be free to move. Body lock ring 280 is provided to prevent housing
282
from moving back uphole and reseating the dogs 276. After initial setting
then, the
housing portion of the tool is permanently moved and the dogs 276 are
permanently
disengaged from anchor sub 234. Following this disengagement, the tool upper
portion (FIGURES 11 and 12) and lower portion (FIGURE 13) are separable using
the
snap in/snap out assembly in order to develop a proper space-out for the
particular
well, the tool may be snapped in/snapped out as many times as necessary until
sufficient weight is committed and the anchor sub 234 supports the latch 314.
In this
CA 02358288 2002-05-09
l4
latter condition the snap out feature is disabled.
Once the space out is appropriate, set down weight which exceeds the shear
strength of shear ring 294 and shear screw 312 is applied. After shearing,
anchor sub
234 moves downhole through lock ring 304 and is retained in this position
until
retrieval is necessary or desired.
In order to retrieve the tool, a tensile load is placed on the anchor sub
which
transmits to the body lock ring 304, the parting ring 316 and the latch 314.
When a
predetermined tensile load is exceeded, the parting ring fails and the anchor
sub 34
moves uphole. This unsupports latch 314 allowing the latch to deflect into
recess 320
and the snap out sub is operational. Continued tensile load will disengage the
upper
portion of the tool from the lower portion for retrieval. The process as
described can
then be repeated with a new or rebuilt upper portion.
While preferred embodiments have been shown and described, various
modifications and substitutions may be made thereto without departing from the
spirit
and scope of the invention. Accordingly, it is to be understood that the
present
invention has been described by way of illustration and not limitation.
