U.S. patent application number 13/455574 was filed with the patent office on 2013-10-31 for emergency elastomer injection system for use on e-line and braided cable.
This patent application is currently assigned to Vetco Gray UK Limited. The applicant listed for this patent is Andrew David Hughes. Invention is credited to Andrew David Hughes.
Application Number | 20130284445 13/455574 |
Document ID | / |
Family ID | 48579583 |
Filed Date | 2013-10-31 |
United States Patent
Application |
20130284445 |
Kind Code |
A1 |
Hughes; Andrew David |
October 31, 2013 |
EMERGENCY ELASTOMER INJECTION SYSTEM FOR USE ON E-LINE AND BRAIDED
CABLE
Abstract
A system and method for sealing a passage around a cable is
disclosed. Embodiments of the system can include an axial passage,
such as a conduit and subsea wellhead housing connected to a
wellbore, that can have a cable extending therethrough. The system
can include an upper restrictor and a lower restrictor for closing
the axial passage. An injection module having an injector and a
reservoir can be fluid communication with the axial passage at an
axial location between the upper restrictor and the lower
restrictor. The injector can discharge a curable sealant initially
stored in the reservoir into the axial passage so that at least a
portion of the sealant contacts the cable at the axial location of
the restrictor while the cable remains static.
Inventors: |
Hughes; Andrew David;
(Glasgow, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hughes; Andrew David |
Glasgow |
|
GB |
|
|
Assignee: |
Vetco Gray UK Limited
Aberdeen
GB
|
Family ID: |
48579583 |
Appl. No.: |
13/455574 |
Filed: |
April 25, 2012 |
Current U.S.
Class: |
166/345 ;
166/363; 166/387; 277/324 |
Current CPC
Class: |
F16J 15/14 20130101;
E21B 33/076 20130101; E21B 33/08 20130101; F16J 15/168
20130101 |
Class at
Publication: |
166/345 ;
277/324; 166/387; 166/363 |
International
Class: |
E21B 33/06 20060101
E21B033/06; E21B 33/064 20060101 E21B033/064; E21B 33/035 20060101
E21B033/035; E21B 23/00 20060101 E21B023/00 |
Claims
1. An apparatus for sealing a passage around a cable, the apparatus
comprising: an axial passage adapted to have the cable passing
therethrough, the cable having a plurality of strands; an upper
restrictor and a lower restrictor for closing the axial passage,
the upper and lower restrictors occupying the annular space between
an inner diameter of the axial passage and an outer diameter of the
cable; and an injection module having an injector and a reservoir,
the injection module being in fluid communication with the axial
passage at an axial location between the upper restrictor and the
lower restrictor, the injector discharging a sealant initially
stored in the reservoir into the axial passage so that at least a
portion of the sealant contacts the cable at the axial location of
the restrictor while the cable remains static.
2. The apparatus according to claim 1, wherein the upper restrictor
and the lower restrictor cause the sealant to flow between at least
a portion of the plurality of strands.
3. The apparatus according to claim 1, wherein the upper restrictor
comprises an upper pair of rams and the lower restrictor comprises
a lower pair of rams, each pair of rams moving axially inward to a
constricted position to constrict the bore, the constricted
position reducing the flow of sealant out of the axial passage,
thereby forcing at least a portion of the sealant to enter a
plurality of voids between the strands.
4. The apparatus according to claim 1, wherein reservoir comprises
a first chamber and a second chamber, the first chamber initially
having a solvent, the solvent being a fluid that removes grease,
and the second chamber initially having the sealant, wherein the
solvent is discharged into the axial passage before the sealant is
discharged into the axial passage.
5. The apparatus according to claim 1, wherein the reservoir is
located in a remotely operated vehicle, the remotely operated
vehicle stabbing into a fluid passage in communication with the
axial passage.
6. The apparatus according to claim 1, wherein the sealant
comprises suspended particulate, the suspended particulate lodging
in flow restrictions within the plurality of strands of the
cable.
7. The apparatus according to claim 1, further comprising a sleeve
in the passage adapted to pass the cable therethrough, the sleeve
adapted to initially have an inner diameter greater than an outer
diameter of the cable, and being deformable to reduce the annular
space between an inner diameter of the sleeve and the outer
diameter of the cable prior to discharging the sealant.
8. The apparatus according to claim 1, wherein the sealant is a
curable polymer that hardens after being injected.
9. The apparatus according to claim 1, wherein at least a portion
of the sealant displaces grease located within the plurality of
braided strands.
10. A method for sealing around a cable extending through a conduit
and a subsea wellhead assembly into a wellbore, the method
comprising: (a) providing upper and lower passage restrictors in
the conduit above the wellhead assembly; (b) providing an injection
module connected to a port through a sidewall in the conduit, the
port being located between the upper passage restrictor and the
lower passage restrictor, the injection module having an injector
and a reservoir, the reservoir initially containing a curable
sealant; (c) actuating the wellbore restrictor to cause the upper
and lower passage restrictors to move radially toward the center of
the wellbore; and (d) injecting the curable sealant from the
injection module through the port in the conduit around the cable
between the upper and lower passage restrictors.
11. The method according to claim 10, wherein the curable sealant
is stored as two or more separate components in two or more
separate vessels in the reservoir, the two or more separate
components reacting to form the curable sealant, and wherein step
(d) comprises mixing the two or more separate components prior to
injecting the curable sealant.
12. The apparatus according to claim 10, wherein the cable
comprises a braided material, and wherein step (d) includes
injecting the curable sealant into the braided material.
13. The apparatus according to claim 10, wherein the cable remains
axially stationary during steps (c) and (d).
14. The apparatus according to claim 10, wherein step (d) occurs
prior to step (c).
15. The apparatus according to claim 10, wherein the reservoir
comprises a first and second container, the first container
initially containing a solvent and the second container initially
containing the curable sealant, and wherein step (d) comprises
first injecting the solvent to remove a grease from the cable and
then injecting the curable sealant.
16. An apparatus for sealing around a cable extending through a
subsea wellhead assembly into a wellbore, the apparatus comprising:
an axial passage having a conduit adapted to extend above the
wellhead assembly and having an axial passage through which the
cable extends, ; a sleeve located in the passage, the cable
extending through the sleeve, and the sleeve being deformable to
reduce the annular space between an inner diameter of the sleeve;
an upper restrictor comprising an upper pair of rams and a lower
restrictor comprising a lower pair of rams, each of the upper pair
of rams and lower pair of rams moving from a first position to a
second position to deform the sleeve to occupy the annular space
between an inner diameter of the axial passage and an outer
diameter of the cable; and an injection module having an injector
and a reservoir, the injection module being in fluid communication
through a sidewall of the axial passage to a location within the
axial passage between the upper restrictor and the lower
restrictor, the injector discharging a curable sealant initially
stored in the reservoir into the axial passage to seal between the
cable and the sleeve.
17. The apparatus according to claim 16, wherein the cable
comprises a plurality of strands and wherein upper restrictor and
the lower restrictor cause the sealant to flow between at least a
portion of the plurality of strands.
18. The apparatus according to claim 17, wherein the sealant
comprises suspended particulate, the suspended particulate lodging
in flow restrictions within the plurality of strands of the
cable.
19. The apparatus according to claim 16, wherein reservoir
comprises a first chamber and a second chamber, the first chamber
initially having a solvent, the solvent being a fluid that removes
grease, and the second chamber initially having the sealant,
wherein the solvent is discharged into the axial passage before the
sealant is discharged into the axial passage.
20. The apparatus according to claim 16, wherein the reservoir is
located in a remotely operated vehicle, the remotely operated
vehicle stabbing into a fluid passage in communication with the
axial passage.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates in general to mineral recovery
wells, and in particular to an apparatus and method for sealing a
wellbore.
[0003] 2. Brief Description of Related Art
[0004] Wire line operations in a wellbore typically use one of
three types of wire line--slick line, e-line, or braided cable. In
order to maintain pressure control during these operations, and
thus prevent pressurized fluid escaping from the wellbore, the wire
line is passed through a pressure controlling device. Devices for
preventing pressure from escaping from the well bore include wire
line blowout preventers ("BOP"), pressure control heads ("PCH"),
lower riser packages ("LRP"), and lubricators.
[0005] These pressure control devices employ different methods of
pressure control including rams, pressure energized packing sets,
and grease. These methods, although different, follow the same
principals in that they all form a seal around the outside of the
wire line. It therefore follows that the outer profile and indeed
construction of the wire line can significantly alter the
effectiveness of the seal generated. For example, on braided cable,
the structure is such that it has a labyrinth of leak paths so even
with tight sealing on the outer diameter, leakage is possible
through the gaps which exist in the structure of the cable itself
In some cases grease is injected into the cable, under high
pressure, to fill the void, thus reducing the ingress and leakage
of wellbore fluids through the cable. Unfortunately, the grease
will follow the same principle of leakage through the labyrinth and
ultimately be depleted over the duration of the operation. The
grease must be replenished to maintain the seal for a length of
time. Therefore, it is desirable to have a semi-permanent seal for
use in emergency situations.
SUMMARY OF THE INVENTION
[0006] Embodiments of the claimed invention relate primarily to
sealing in an emergency. Because e-line and braided cable can have
a labyrinth of leak paths, conventional sealing techniques require
constant grease injection in order to maintain a seal. Under
certain circumstances, such as an emergency condition, the seal
around the wire line may be required to maintain pressure control
for a significant length of time. The grease supply will therefore
deplete and may be not be replenished or maintain enough pressure
to seal. Embodiments of the claimed invention can include a
cylinder of sealant, such as an elastomer, epoxy, or some other
plastic, any of which can be stored in a liquid or paste form. In
some embodiments, the sealant can include particles of
predetermined sizes. The sealant can be stored in a two- part resin
form, where it can remain in a fluid state for a long period of
time. Upon actuation of an emergency sequence, an injection module
would deploy the pressurized sealant to a pre-defined chamber
wellbore member via one or several ports. Upon injection, it would
begin to chemically change and increase in viscosity until it is
set, ultimately forming a seal within the labyrinth of the e-line
or braided cable.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] So that the manner in which the features, advantages and
objects of the invention, as well as others which will become
apparent, are attained and can be understood in more detail, more
particular description of the invention briefly summarized above
may be had by reference to the embodiment thereof which is
illustrated in the appended drawings, which drawings form a part of
this specification. It is to be noted, however, that the drawings
illustrate only a preferred embodiment of the invention and is
therefore not to be considered limiting of its scope as the
invention may admit to other equally effective embodiments.
[0008] FIG. 1 is a partial side view of an embodiment of a pressure
control head with an injection module according to an embodiment of
the present invention.
[0009] FIG. 2 is a partial side view of the embodiment of FIG. 1,
showing the pressure control head in a pressurized position.
[0010] FIG. 3 is a partial side view of the embodiment of FIG. 1,
showing the pressure control head in a pressurized position and the
cable sealing apparatus having injected sealant into the cable.
[0011] FIG. 4 is a cross section of an exemplary embodiment of
cable.
[0012] FIG. 5 is a cross section of another exemplary embodiment of
cable.
[0013] FIG. 6 is a partial side view of a cable having sealant
injected into it according to an embodiment of the present
invention.
[0014] FIG. 7 is a partial sectional side view of an injection
module and a lower riser package according to an embodiment of the
present invention.
[0015] FIG. 8 is a partial sectional side view of an injection
module and a blowout preventer according to an embodiment of the
present invention.
[0016] FIG. 9 is a partial sectional side view of an injection
module positioned within a remotely operated vehicle, and a blowout
preventer according to an embodiment of the present invention.
[0017] FIG. 10 is a partial sectional side view of an injection
module and a lubricator according to an embodiment of the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0018] The present invention will now be described more fully
hereinafter with reference to the accompanying drawings which
illustrate embodiments of the invention. This invention may,
however, be embodied in many different forms and should not be
construed as limited to the illustrated embodiments set forth
herein. Rather, these embodiments are provided so that this
disclosure will be thorough and complete, and will fully convey the
scope of the invention to those skilled in the art. Like numbers
refer to like elements throughout, and the prime notation, if used,
indicates similar elements in alternative embodiments.
[0019] Referring to FIG. 1, cable 100 is a flexible cable suspended
through pressure control head ("PCH") 102 into a wellbore (not
shown). Cable 100, which has a small diameter relative to the
wellbore, can be used to lower a wireline-run tool into a wellbore.
PCH 102 can be used to form a seal against cable 100 so that
pressure from the wellbore is not released around cable 100 during
wireline operations. Bore 104 is an axial passage through PCH 102.
In some embodiments, bore 104 is sufficiently large inner diameter
("ID") that a wireline-run tool can pass through PCH 102. In other
embodiments, cable 100 can be run through PCH 102 prior to
attaching the wireline-run tool.
[0020] As best shown in FIGS. 4 and 5, cable 100 can be a braided
cable having individual strands 106 of wire or other fibers.
Strands 106 can be twisted or woven together to provide a cable
with sufficient tensile strength and flexibility to lower a
wireline-run tool into the wellbore. Even with a tight twisting or
braiding of strands 106, however, gaps 108 can exist between
strands 106. Cable 100 can also have an uneven outer profile, or
outer surface, because of the gaps 108 around its outer diameter.
Because strands 106 generally run in the axial direction, gaps 108
can form a labyrinth of leak paths through which fluid can travel.
As shown in FIG. 4, a cable 100 having relatively large diameter
wires or strands 106 can have large gaps 108. As shown in FIG. 5, a
cable 100' having a larger number of small diameter strands 106'
can have a smaller gaps 108', albeit a larger number of them. Cable
100 can be an electric line, or "e-line," wherein one or more of
the strands 106 are insulated electrical conductors. In some
embodiments, the outer diameter of cable 100 can have a protective
or insulated sheath 110. Sheath 110 can be a braided sleeve around,
for example, individually insulated wires. A leak path can exist
for fluid to pass through sheath 110 and then along the individual
wires.
[0021] Upper lubricator 112 and lower lubricator 114 can be used to
form a seal against cable 100. As one of skill in the art will
appreciate, lubricators 112 and 114, which can be conventional, can
include fingers for imparting grease to cable 100 as cable 100
moves through PCH 102. The grease can fill gaps 108 within cable
100 and along the outer diameter of cable 100. Lubricators 112 and
114 can form a seal against cable 100 during routine
operations.
[0022] During a high pressure condition in the wellbore, the seal
between cable 100 and lubricators 112, 114 may be inadequate. A
restrictor, such as pressure energized packing sets 116, can be
used to establish a more robust seal around cable 100. In one
embodiment, packing sets 116 can include chamber 118, connected to
pressure port 120. Sealing face 122 is the inner diameter wall of
chamber 118 and, thus, faces radially inward toward the axis of
bore 104. As best shown in FIG. 2, when pressure, such as pneumatic
or hydraulic pressure, is applied through pressure port 120,
chamber 118 expands to cause sealing face 120 to move radially
inward toward the center of bore 104 to occupy the annular space of
bore 104. As chamber 118 expands so that sealing face 122 presses
against an outer diameter of cable 100 to limit the flow of
wellbore fluid through bore 104. As with conventional pressure
control heads, the grease imparted by lubricators 112, 114 can
reduce the flow of wellbore fluid through gaps 108 between strands
106 of cable 100.
[0023] During a period of prolonged exposure to a high pressure
condition, the grease imparted by packing sets 112 and 114 may be
insufficient to maintain a seal. The high pressure can, over time,
displace the grease from gaps 108, in which case wellbore fluid can
flow around and through cable 100 and past packing set 116 to
ultimately leak out of the wellbore. In some circumstances, such a
prolonged high pressure condition can be an emergency
condition.
[0024] An injection module 124 can be connected to PCH 102.
Injection module 124 is used to inject a curable sealant 126 into
an axial passage such as bore 104 so that sealant 126 contacts at
least a portion of cable 100. In one embodiment, sealant 126 is
injected into a portion of bore 104 that is located between two
flow restrictors such as, for example, packing sets 116. In some
embodiments, the sealant can be injected into other portions of the
wellbore or riser, provided that sealant 126 contacts cable 100.
The flow restrictors force the sealant to flow around and through
cable 100. Without the flow restrictors, sealant 126 could flow
freely out of bore 104 rather than being injected into gaps
108.
[0025] As shown in FIGS. 1-3, injection module 124 has an injection
port 128, which is a tube or other fluid path from injection module
124 into bore 104. Injection port 128 is located between two flow
restrictors such as, for example, packing sets 116. A one-way
valve, such as check valve 130, can be used to prevent fluid in
bore 104 from moving through injection port 128 into injection
module 124. Injection module 124 can have a syringe type injector,
wherein the sealant is initially stored in reservoir 132 and
plunger 134 is actuated to force the sealant out of the reservoir
and into bore 104. In the embodiment shown in FIGS. 1-3, reservoir
132 is a part of the syringe injector. As best shown in FIG. 3,
reservoir 132 can hold a sufficient volume of sealant 126 to
adequately fill bore 104 between packing sets 116 with enough
sealant 126 to cause at least a portion of the sealant to contact
the outer diameter of cable 100. In one embodiment, there is
sufficient sealant 126 to cause at least a portion of the sealant
to flow through gaps 108 in the vicinity of packing sets 116.
[0026] Plunger 134 can be actuated by any of a variety of
techniques. For example, plunger 134 could be connected to a
hydraulic piston and hydraulic pressure from the surface platform
or from a remotely operated vehicle ("ROV") (not shown in FIGS.
1-3) can move the piston to actuate plunger 134. Alternatively,
plunger 134 could have a lead screw and an electric motor could
rotate the lead screw to actuate plunger 134. In another
embodiment, an ROV can mechanically actuate injection module 124.
For example, the rod 136 of plunger 134 can be accessible from
outside of the wellbore member such as PCH 102, such that an ROV
(not shown in FIGS. 1-3) can move the rod to actuate plunger 134.
In one embodiment, injection module 124 is only actuated after the
other sealing apparatus in the wellbore, such as PCH 102, blowout
preventers (not shown in FIGS. 1-3), and various valves (not shown
in FIGS. 1-3) are closed to seal the wellbore.
[0027] Sealant 126 can be any type of sealant for sealing gaps 108
or forming a seal between the outer diameter of cable 100 and the
cable-facing surface of a restrictor, such as sealing face 120.
Sealant 126 can be stored as a liquid or paste, and can remain in a
fluid state for a long period of time. Sealant 126 can chemically
change upon injection into bore 104 so that it begins to harden and
increase in viscosity. In one embodiment, sealant 126 can be an
elastomer that sets, or hardens, under a pre-determined condition.
For example, the elastomer could set after reaching a certain
temperature or pressure. In another embodiment, the elastomer could
set upon being exposed to a particular chemical. In the embodiment
wherein the elastomer sets in response to reaching a certain
pressure, the pressure can be selected so that bore 104 can be
filled with the elastomer and the elastomer will set only after the
pressure is sufficiently high to cause a portion of the elastomer
to enter gaps 108 or enter the gap that may exist between cable 100
and sealing face 120. In one embodiment, sealant 126 can be a
curable sealant that hardens after being injected, such as, for
example, a curable polymer, a binary epoxy, or two-part resin,
wherein the sealant is initially stored as two separate liquids. As
shown in FIG. 6, the two liquids can be mixed as they are injected
into the bore, thus forming a sealant which will set in a
predetermined amount of time or in response to predetermined
conditions. In the embodiments described, the sealant can be a
semi-permanent sealant such that removing the sealant, after it has
set, requires a specific solvent or requires machining and re work
of the cavity and bores.
[0028] In one embodiment, sealant 126 can include a fluid suspended
particulate such that, upon injection, a portion of the particulate
will lodge in flow restrictions such as gaps 108 or the annular
space between cable 100 and sealing face 120. As shown in FIG. 6,
various sizes of particulate can be used to form seals within cable
138 by sealing gaps between strands 140. In one embodiment using at
least two sizes of particulate, larger particulate 142 can fill
large gaps 144 between strands 140, and then smaller particulate
146 can lodge between the larger particulate and the strands, and
can fill small gaps 148, to form a tighter seal. A liquid sealant
can then complete the seal, if needed, by adhering to the large and
small particulate and the strands.
[0029] In one embodiment, as shown in FIG. 7, injection module 150
can include more than one reservoir. For example, injection module
150 can include a first reservoir 152 containing a first fluid 154
and a second reservoir 156 containing a fluid 158. The fluids
within the reservoirs 152, 156 can be injected by plungers 160 and
162, respectively. In one embodiment, the fluid can be contained in
reservoirs 152, 156 by rupture discs 164 to keep the fluid from
mixing prematurely. Alternatively, a valve, check valve, or other
device can be used to contain the fluids within reservoirs 152,
156. In embodiments where it is desirable to have the fluids mix
prior to entering bore 104, the fluids can be mixed in tubing 166.
In one embodiment, tubing 166 can include a mixing device (not
shown) to promote the mixing of the fluids. The mixing device can
be, for example, a vortex or series of baffles. This can be useful
when the sealant is an epoxy having a separate curing agent. The
reservoirs 152, 156 can be, but are not required to be, the same
size or the same configuration. The fluid or fluids from the
reservoirs 152, 156 can travel through tubing 166 to injection port
168, which is in communication with bore 170. A check valve 172 can
be used to prevent fluid from bore 104 from entering tubing
166.
[0030] In one embodiment, the fluids can be a solvent and an
elastomer, or a solvent and an epoxy. For example, reservoir 152
can initially contain a solvent that is suitable to displace
grease, while reservoir 156 initially contains an elastomer
sealant. The solvent, such as, for example, methanol, can be
injected into bore 170 first, and used to displace grease from
cable 174. After a predetermined condition, such as a given amount
of time, the elastomer from reservoir 156 can be injected into bore
170 to fill gaps in cable 174. This can be useful when, for
example, grease is occupying the gaps in cable 174 and that grease
would prevent the elastomer from filling the gaps. Because the
grease can be displaced over time, and thus undermine the seal, it
can be beneficial to displace the grease before injecting the
elastomer. In embodiments that do not use a solvent, the pressure
of the sealant can displace some or all of the grease as the
sealant is injected into the bore. In one embodiment, a solvent
from a first reservoir 152 can be used to first displace and flush
any grease that may be on cable 174, followed an etching agent from
the second reservoir 156. The etching agent can be used to clean
and prepare surfaces within cable 174 and within bore 170 to better
adhere to the sealant. A sealant from a third reservoir (not shown)
can then be injected under high pressure to fill the gaps and
adhere to the surfaces of cable 174 and bore 170.
[0031] Still referring to FIG. 7, injection module 150 can be
connected to lower riser package ("LRP") 176. Restrictors such as
rams 178 can be used to close bore 170. A sleeve 182 can run
through LRP 176 and be used to guide cable 174. Injection port 168
can be connected to sleeve 182 so that sealant is injected into
sleeve 182 when injection module 150 is actuated. When rams 178
move inward toward the center of bore 170, they apply sufficient
pressure to deform sleeve 182 around cable 174 such that the inner
diameter of sleeve 182 is pressed against the outer diameter of
cable 174. When the sealant is injected into sleeve 182, the flow
path of least resistance will be through the gaps 108 (FIGS. 4
& 5), thus imparting sealant into cable 174. Furthermore, less
sealant is required because the narrow diameter of sleeve 182 and
the constriction of sleeve 182 due to rams 178 reduces the volume
of sealant that must be injected. In some embodiments, the sealant
does not flow axially past rams 178 due to the tight constriction.
In some embodiments, some sealant does flow past rams 178 is it
fills gaps 108.
[0032] The sealant injection system is not limited to use in a
pressure control head. It can be used with any of a variety of
wellbore devices, especially devices that constrict the bore around
a wireline. As shown in FIG. 8, injection module 186 can be used in
conjunction with blowout preventers 188. In this embodiment, rams
190 move inward toward the center of bore 192 to prevent fluid flow
through bore 192. Injection module 186 can inject sealant 194 into
bore 192 to fill gaps within cable 196, which is extended between
rams 190. Sealant 194 can flow between rams 190 and adhere to the
opposing faces of rams 190 and the annular gaps between rams 190
and cable 196. Because it is injected under high pressure, sealant
194 can be forced through the strands of cable 196, in the vicinity
of rams 190, and fill gaps within cable 196.
[0033] Still referring to FIG. 8, injection module 186 can be of
various configurations suitable for injecting sealant into bore
192. In the embodiment shown in FIG. 7, injection module 186
includes a reservoir 198 that is a cylindrical vessel, although
reservoir 198 can be other shapes. Pump 200 is connected to
reservoir 198. Pump 200 can be any type of pump including, for
example, a diaphragm pump or a centrifugal (impeller) pump. Tubing
202 can connect injection module 186 to bore 192. One or more
injection ports 204 can be used to inject sealant 194 into bore
192. FIG. 7 is shown with two injection ports 204 spaced apart
around bore 192, each with a check valve 206. In some embodiments,
the injection ports can be located axially nearer to one or the
other restrictor such as rams 190.
[0034] Referring to FIG. 9, injection module 208 can be located
apart from riser 210. For example, injection module 208 can be
located inside a remote operating vehicle ("ROV") 212. In this
embodiment, an injection port 214 is connected to riser 210,
between a pair of BOPs 216. Connector 218 of ROV 212 can connect to
injection port 214 to inject a sealant into the bore of riser 210.
For example, ROV 212 can stab into a fluid passage in communication
with injection port 214 and, thus, in communication with the bore
of riser 210. Connector 218 can be, for example, a quick disconnect
fitting that mates to a corresponding quick disconnect fitting on
injection port 214. ROV 212 can connect connector 218 to injection
port 214 so that after the restrictor, such as BOPs 216, close
around cable 220, injection module 208 can inject sealant through
injection port 214 to infuse cable 220 with sealant.
[0035] Referring to FIG. 10, in another embodiment, injection
module 222 can be used with lubricator 224. In this embodiment, the
restrictors are the lubricators 226, with no other restrictors
required. Injection module 222 can inject sealant through injection
port 228 and into bore 230 of lubricator 224. The sealant can
permeate through bore 230 and into cable 232, so that cable 232 can
form a better seal against lubricators 226. In the embodiment shown
in FIG. 10, injection module 222 has a lead screw 234 to inject
sealant from reservoir 236, through check valve 238, into bore
230.
[0036] Referring back to FIGS. 1-3, in operation of an embodiment,
a seal can be formed around cable 100 that extends through a
conduit, such as bore 104, and a subsea wellhead assembly into a
wellbore. The seal can be formed by, for example, providing upper
and lower passage restrictors such as packing set 116 in the
conduit above the wellhead assembly. An injection module 124 can be
connected to injection port 128, which is a port through a sidewall
of bore 104. Injection port 128 is located between the upper
packing set 116 and the lower packing set 116. Injection module 124
can have an injector and a reservoir 132, the reservoir 132 can
initially contain a curable sealant 126.
[0037] The wellbore restrictors, such as packing sets 116, can be
actuated so that sealing face 122 of the restrictors move radially
toward the center of bore 104. Curable sealant can be injected from
injection module 124, through injection port 128 so that curable
sealant 124 flows around cable 100 between the upper and lower
passage restrictors. In some embodiments, the restrictors can be
actuated before curable sealant 124 is injected.
[0038] In some embodiments, the restrictors can be actuated after
curable sealant 124 is injected. Curable sealant 124 can fill bore
104, permeate gaps 108 (FIG. 4) in cable 100, and fill any annulus
space that may exist between the restrictors (such as sealing face
122 of packing set 116) and the outer diameter of cable 100. In
embodiments, curable sealant 124 can cure to form a plug
encompassing cable 100 and filling the space between cable 100 and
the as-yet un-actuated restrictors. Subsequently, when the
restrictors are actuated, sealing face 122 can move inwards to
exert pressure against the now cured, or solidified, curable
sealant 124, thus energizing curable sealant 124 as a seal between
sealing face 122 and cable 100. In some embodiments, curable
sealant 124, after it has cured, can provide the assistance of a
preload force between any or all sealing surfaces.
[0039] In embodiments, curable sealant 124 can be stored as two or
more separate components in two or more separate vessels 152, 156
in the reservoir. The two or more separate components 154, 158 can
react to form the curable sealant when the components are mixed
prior to or during the injection of the components through
injection port 128. In embodiments, cable 100 can include a braided
material and curable sealant 124 can be injected into the braided
material. In embodiments, cable 100 can be remain axially
stationary during the injection of curable sealant 124 and during
the actuation of the restrictors. In some embodiments, cable 100
can be axially moved after the injection of curable sealant 124 so
that the portion of cable 100 having sealant 124 is moved toward a
restrictor prior to actuating the restrictor. In some embodiments,
the reservoir can include a first and second container. The first
container can initially contain a solvent and the second container
can initially contain curable sealant 124. The solvent can be
injected before the sealant to remove grease from cable 100, and
then curable sealant 124 can be injected.
[0040] While the invention has been shown or described in only some
of its forms, it should be apparent to those skilled in the art
that it is not so limited, but is susceptible to various changes
without departing from the scope of the invention.
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