The invention relates generally to connecting a main well bore and a lateral branch.
In the field of multilateral construction and production operations, an important attribute of a junction is the connectivity of the lateral branch with the main bore. Partial or total loss of connectivity of the main bore with a lateral branch may cause fluid production loss. Major connectivity problems may also result in partial or total obstruction of the main or lateral bore at the level of the lateral junction. The consequences are a substantial penalty to the operator of a well in the form of lost opportunity, increased operating cost, or lost production. The root cause of not being able to achieve or maintain connectivity at a lateral junction can be divided into two general areas: mechanical integrity problems and production of solids from formation surrounding the junction.
With some lateral connection assemblies, reliance is made on cement or other filler material to retain the position of the junction. However, cement may not provide sufficient structural integrity, particularly when the formation shifts due to production of fluids, which may crack or fracture the cement. Also, some lateral connection assemblies do not provide adequate sealing against solids (e.g., sand or other debris) in the surrounding formation. As a result, solids may enter the production path, which are produced as contaminants to the surface. The presence of contaminants may damage production equipment. Also, well operation costs may be increased due to the need to dispose such contaminants.
In a well having at least one lateral branch and a main well bore, the issue of controlling fluid flow from different zones (e.g., fluid from a lateral branch and fluid from a zone in the main wellbore or from another lateral branch) arises. Sometimes it may not be desirable to commingle fluids from different sources. For example, a well having multiple lateral branches may have several owners, with a first lateral branch belonging to a first owner and a second lateral branch belonging to a second owner, and so forth. Consequently, a need arises for controlling fluid flow from multiple sources in a multilateral well.
In general, according to one embodiment, a junction assembly for use at a junction between a lateral branch and a main well bore includes a template having a lateral window for positioning proximal the junction and a connector adapted to be sealably engaged in the template. A portion of the connector extends through the lateral window. Plural flow paths include a first flow path in communication with the lateral branch, and a second flow path in communication with a portion of the main well bore.
Other or alternative features will become apparent from the following description, from the drawings, and from the claims.
In the following description, numerous details are set forth to provide an understanding of the present invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.
As used here, the terms “up” and “down”; “upper” and “lower”; “upwardly” and “downwardly”; “upstream” and “downstream”; “above” and “below” and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly described some embodiments of the invention. However, when applied to equipment and methods for use in wells that are deviated or horizontal, such terms may refer to a left to right, right to left, or other relationship as appropriate.
A lateral window 24 is formed within the main well casing, either having been milled prior to running and cementing of the main well casing within the bore hole or having been milled downhole after the main well casing has been run and cemented. A lateral branch bore 26 is drilled by a branch drilling tool (not shown) that is diverted from the main well bore through the window 24 and outwardly into the formation surrounding the main well bore. The lateral branch bore 26 is drilled along an inclination that is established by a whipstock or other suitable drill orientation control. The branch bore 26 is also drilled along a predetermined azimuth that is established by the relation of the drill orientation control with an indexing device (not shown) that is connected into the casing string or set within the casing string.
A lateral branch connector 28, engageable within the lateral branch template 18, is attached to a lateral branch liner 30 to connect the lateral branch to the main well bore. A ramp 32 cut at a shallow angle in the lateral branch template 18 serves to guide the lateral branch connector 28 toward the casing window 24 while sliding downwardly along the lateral branch template 18. In addition, as further described below, the lateral branch template 18 and lateral branch connector 28 have cooperable inter-engagement members that, in addition to connection and sealing functions, also serve to guide the lateral branch connector 28 through the lateral branch template 18 and a window 29 of the lateral branch template 18 into the lateral branch bore 26. The window 29 of the template 18 is azimuthally oriented to align to the direction of the lateral branch bore 26.
Optional seals 34 which may be carried within optional seal grooves 36 of the lateral branch connector 28, as shown in
The lateral branch connector 28 is designed to withstand loads that are induced thereto while running the liner 30, attached at the end of the connector 28, into the lateral branch bore 26. Once the lateral branch connector 28 is in fixed position and orientation with respect to the template 18, an interlocking and sealed connection with the lateral branch template 18 is established. The lateral branch connector 28 thus supports a lateral opening, which allows fluid and production tools to pass through the junction between a main production bore 38 (above the junction) and the lateral branch bore 26.
The lateral liner 30 connects to, or alternatively, stabs into the lateral branch connector 28 at its upper end and connects to the upper portion of a lateral liner (not shown) that has been installed prior to installing the connecting apparatus. In the alternative, the lateral liner 30 sets into the open wellbore of the lateral branch along its entire length or along a portion of the lateral branch. The lateral liner 30 also has many properties of liners that are installed in wells to isolate production or injection zones from other formations. The lateral liner 30 may be or may not be cemented depending upon the desires of the user. The lateral liner's sealed and mechanically interlocked relation with the lateral branch template 18 obviates the need for cementing because, unlike conventional cement junctions, the junction assembly 10 is structurally capable of withstanding mechanical or pressure induced forces that cause failure of conventional cemented lateral branch junctions.
As an alternative, the lateral liner 30 may carry inside or outside its wall some reservoir monitoring equipment, which measures, processes and transmits important data that identifies the evolution of the reservoir characteristics while producing hydrocarbon products. This information may be transmitted to surface via suitable transmission means such as electric lines, electromagnetic or induction through or along the liner itself provided adequate relays and connections up to the lateral connection with the parent well.
Also, as an option, the lateral branch template 18 may include an active diverting device that is controlled from surface prior to lowering the equipment in a pre-selected lateral branch by creating a temporary mechanical diverter in the main bore.
In accordance with some embodiments, as shown in
As shown in
In
As shown in
Each continuous groove 112 has an upper end 112A (the “proximal end”) and a lower end 112B (the “distal end”). In the embodiment shown, the width of the groove 112 near the upper end 112A is larger than the width of the groove 112 near the lower end 112B. The width of the groove 112 gradually decreases along its length, starting at the upper end 112A, so that the groove has a maximum width at the upper end 112A and a minimum width at the lower end 112B. In other embodiments, other arrangements of the continuous grooves 112 are possible. For example, each continuous groove can have a generally constant width along its length. Alternatively, instead of a gradual variation of the groove width, step changes of the groove can be provided.
The enlarged upper portion of each groove 112 provides an orientation mechanism for guiding a corresponding rail 126 of the lateral liner connector 28 into the groove 112. The upper portion of the groove 112 has at least one angulated surface 119 for guiding the connector rail 126.
The lower end 112B of each groove 112 in the lateral branch template 18 defines a lower connector stop 116 which is engageable by the lower end of the connector rail 126 to prevent further downward movement of the lateral branch connector 28 once the connector rails 126 are fully engaged in the grooves 112.
Referring to
Each continuous rail 126 has an upper end 126A (the “proximal end”) and a lower end 126B (the “distal end”). The width of the upper end 126A is larger than the width of the lower end 126B. The rail 126 gradually decreases in width along its length starting from the upper end 126A. In other embodiments, other arrangements of the rails 126 are possible. The variation of the width of the rails 126 is selected to correspond generally to the variation of the width of the grooves 112 in the template 18.
As shown in
Also, as the lateral branch connector 28 is forced to follow the inclined path provided by the inclined grooves 112 and rails 126, the lateral branch connector 28 is elastically and/or plastically deformed to follow the inclined path. Thus, as bending force is applied to the connector housing 121 by the ramping action of the rail and groove interlocks, the connector housing 121 is deformed or flexed to permit its lower end to move through the casing window and into the lateral branch bore.
The continuous rail and groove interlocking mechanism shown in
In an alternative embodiment, instead of a continuous rail 126 as shown in
Another desired feature of some embodiments of the invention is that a continuous fluid seal path is defined around the periphery of the lateral window 29 of the template. As schematically illustrated in
To provide the closed seal path, the sealing element in one embodiment is routed along the rails 126 (
At the lower end of the continuous seal path 150, the sealing element wraps around, or makes a “U-turn” around the lower end 126B of the rails 126. Thus, when the lower end 126B, and the sealing element wrapped around the lower end, engages the stop 116 (
Referring to
In the illustrated example, the sealing element 160 undulates along the rail 126 to form a generally wavy sealing element. The generally wavy form of the sealing element 160 enables a more secure engagement in a groove formed in the rail 126. Other shapes of the sealing element 160 may be used in other embodiments.
In the template 18 shown in
Further downwardly, as shown in
The offset of the inner bores 142 and 144 (and of the connector 28 and template 18) increases at cross-section 5—5, as shown in FIG. 5. Here, the bores 142 and 144 provide completely separate paths. In addition, the widths of the grooves 112 and rails 126 are reduced further. Near the lower end of the junction assembly, at cross-section 6—6, the connector 28 and template 18 are further offset from each other. The connector rails 126 and template grooves 112 near the distal end of the junction assembly are also shown.
In accordance with another feature of some embodiments of the invention, slots or conduits are also defined in the connector 28 and/or template 18 to enable the routing of communications lines (e.g., electrical lines, fluid pressure control lines, hydraulic lines, fiber optic lines, etc.). As shown in
In addition to the communications lines 146 and conduits 148, similar communications lines 150 can also be extended along conduits 152 formed on the outer surface of the template 18 housing. Again, two sets of communications lines 150 and conduits 152 are illustrated for purposes of example. The communications lines 150 enable communications with devices located below the junction assembly.
Another feature of some embodiments is the presence of seals 154 formed between respective grooves 112 and rails 126 (as shown in FIGS. 2-6). The seals 154 are provided primarily to prevent the entry of solids from the surrounding formation and wellbore into the bores 142 and 144. In one embodiment, the seals 154 are elastomer seals—although other types of seals can be employed in other embodiments. In another embodiment, an adequate seal may be provided by engagement of each continuous rail 126 with a corresponding groove 112 (without the use of the seal 154). The engagement of the rail 126 and groove 112 provides a tortuous path that makes it difficult for solids to traverse from outside the junction assembly into the junction assembly. The tortuous path is provided by the plural edges or surfaces of the rail 126 being in abutment with corresponding plural edges or surfaces of the groove 112.
An adjustment adapter mechanism shown at 52 in
The selective orienting keys 56 of the diverter are seated within specific key slots of the lateral branch template 18 while the upper portion 59 of the diverter will be rotationally adjusted relative thereto for selectively orienting the tapered surface 58. Isolating packers 60 and 62 are interconnected with the lateral branch template and are positioned respectively above and below the casing window 24 and serve to isolate the template annular space respectively above and below the casing window.
According to one method for connecting a lateral branch liner to a main well casing, the main or parent well casing is located into the main well bore and supports one or more indexing devices that can be permanently installed in the parent casing below the junction. Indexing features include positive locating systems to position accurately the template 18 in depth and orientation with respect to the lateral window 24. The main well casing has one or a plurality of lateral windows referenced to the indexing device or devices to thus permit one or more lateral branch bores to be constructed from the main wellbore and oriented according to the desired azimuth and inclination for intersecting one or more subsurface zones of interest.
The lateral window(s) is typically milled after main well casing is set and cemented. In this case, the main well casing does not need to be oriented before cementing. Alternatively to the above, the lateral window can be pre-fabricated into a special vessel installed in line in the main well casing string. In this case, the main well casing requires orientation before cementing in order to let the orientation of the lateral branch conform with the well construction plan.
The lateral branch template 18 is properly located and secured into the main well bore by fitting into an indexing device to position accurately the template in depth and orientation with respect to the lateral window 24 of the main well casing. The lateral branch template 18 has adjustment components that are integrated into the lateral branch template 18 and which allow for adjusting the position and orientation of the lateral branch template with respect to the lateral casing window. The main production bore 38 allows fluid and production equipment to pass through the lateral branch template with a minimum restriction so access in branches located below the junction is still allowed for completion or intervention work after the template 18 has been set. The lateral opening 29 in the lateral branch template 18 provides space for passing a lateral liner and for locating the lateral branch connector 28 which fits in it with tight tolerances taking advantage of controlled prefabricated geometries.
The lateral branch template 18 incorporates a landing profile and a latching mechanism that allows supporting and retaining the lateral branch connector 28 so it is positively connected to the main production bore 38. The lateral branch template 18 also incorporates guiding and interlocking features (continuous grooves 112 shown in
The lateral branch template 18 also provides a selective landing profile and associated orienting profile in which can fit a diverter used to direct equipment from uphole through the casing window and toward the lateral branch bore. The upper and lower ends of the lateral branch template are treated so production tubing can be connected without diameter restriction by means of conventional production tubular connections. The lateral branch template provides a polished bore receptacle for eventual tie back at its upper portion and is provided with a threaded connection at its lower portion. As an option, the annular space between lateral branch template and main well casing is isolated below and above the lateral window by means of annular packer elements to provide the well ultimately and selectively with isolation of either the lower section of the main production bore or the lateral branch bore.
Referring to
The valve 202 has one or more locking dogs 206 that are engageable in corresponding one or more profiles 208 formed in the lateral branch connector 28. Alternatively, if the valve 202 is positioned further downstream in the lateral branch bore 26, the profile(s) 208 are formed in the lateral branch liner 30. An inner surface of the liner 30 (or alternatively the lateral branch connector 28) provides a seal bore 210 in which a seal 212 carried by the valve 202 is sealingly engageable. The valve device 202 includes a valve 214 that can be actuated between an open position and a closed position, and optionally, to one or more intermediate choke positions, to control the flow of fluid through a longitudinal bore of the valve device 202.
An engagement adapter 216 at the upper end of the valve device 202 is engageable by a corresponding member 222 on the kick-over tool 204. The kick-over tool 204 has a section 224 that is pivotably mounted with respect to a main section 226.
Actuating members 228 are mounted on the outside of the kick-over tool 204 and are adapted for engagement in profiles 230 formed in the connector 28. Alternatively, the profiles 230 can be formed in the casing 12 if the actuating members 228 of the kick-over tool 204 are formed further upwardly. When the actuator members 228 are engaged in the profiles 230, the kick-over tool 204 is triggered to allow the lower section 224 to pivot towards the lateral branch bore 26. The lower section 224 can be lowered into the lateral branch bore 26 to enable engagement of the locking dogs 206 on the outside of the valve device 202 in the profiles 208 of the lateral branch connector 28 or the lateral branch liner 30. Once the valve device 202 is engaged in the profiles 208, the kick-over tool 220 can be disengaged from the valve 202. The kick-over tool 220 is then raised to a surface, leaving the valve device 202 behind.
As an option, the upper and or lower ends of the lateral branch template 18 may be equipped with an inductive coupler mechanism to enable the communication of electrical power and signaling with the valve 202 through the template 18 and along the main completion conduit (e.g., production tubing, etc.). The inductive coupler mechanism shown in
The lateral branch connector 28 is shown to be provided with an inductive coupler portion 68. A tubing encapsulated cable or permanent downhole cable, which can be one of the communications lines 146 shown in
Although not shown, a power supply and control line extends along the production conduit. The power supply and control line terminates in an inductive coupler portion (not shown) at the lower end of the production conduit. When the production conduit is engaged in the polished bore receptacle 72, the inductive coupler portion connected to the power supply and control line is inductively coupled to the parent bore inductive coupler portion 68. The upper end of the power supply and control line is connected to a well control unit (or to a downhole control unit).
Electrical energy is inductively coupled to the parent bore inductive coupler portion 68, which electrical energy is communicated over the cable 146 to the lateral branch inductive coupler portion 70. The electrical energy in the inductive coupler portion 70 is inductively coupled to an inductive coupler portion 219 in the valve 202. The electrical energy (including power and signaling) is communicated to power the valve 202 and to actuate the valve 202 between an open position, a closed position, and optionally, at least one intermediate choke position.
In an alternative embodiment, the connector 28 is connected to a lower end of a production tubing or other completion equipment so that the connector 28 and tubing or other completion equipment can be run into the wellbore together. In this arrangement, an electrical cable or conductor can be run from the connector 28 all the way to the well surface.
An efficient method and apparatus is thus provided to position an intelligent completions device in the lateral branch bore and to communicate with such an intelligent completions device. The ability to position and communicate with intelligent completions devices in a lateral branch bore provides useful tasks to control and to enhance the productivity of the lateral branch bore 26.
In a well having at least one lateral branch and a main well bore, the issue of controlling fluid flow from different zones (e.g., fluid from a lateral branch and fluid from a zone in the main well bore) arises. It may be desirable to provide separate flow paths for fluids from the different zones for various reasons. For example, sometimes it may not be desirable to commingle fluids from different sources. A well having multiple lateral branches may have several owners, with a first lateral branch belonging to a first owner and a second lateral branch belonging to a second owner, and so forth.
Referring to
A lateral branch connector 250 or second part, which is similar to the lateral branch connectors described above, is sealably connected to an upper portion of the liner 254 in the lateral branch 26. The sealed connection between the lateral branch connector 250 and the liner 254 is accomplished by a seal bore connection 256 in one embodiment. The upper part of the liner 254 has a seal bore 255 into which the lower part of the lateral branch connector 250 can be sealably inserted or stabbed. Other types of sealed connections can be provided in other embodiments. The lateral branch connector is connected to a lateral branch template 252.
The lateral branch connector 250 or second part is sealably engaged to a lateral branch template 252 or first part. The sealed engagement or connection of the connector 250 and the template 252 can be accomplished using sealing mechanisms discussed above. The sealed engagement between the template 252 and connector 250 protects against influx of solids (e.g., sand and other debris) and fluids from the surrounding formation and wellbore into the flow paths. Thus, the sealed engagement provides hydraulic isolation to the interior of the template 252 and connector 250 (the junction assembly) from the surrounding formation and wellbore.
The upper part of the lateral branch connector 250 includes a seal bore 278 for receiving parts of tubings 264 and 272. The first tubing 264 communicates with the main bore 22, and the second tubing 272 communicates with the lateral branch 26 through the lateral branch connector 250. The tubings 264 and 272 provide separate and preferably isolated flow paths for fluid communication with the lateral branch 26 and main bore 22.
In the illustrated embodiments, the junction assembly has a diverter 251 for diverting intervention tools into the lateral branch 26. In other embodiments, the diverter 251 is omitted.
In one embodiment, the tubing 272 extends through or partially through the connector 250. In another embodiment, the tubing 272 connects to the seal bore 278 but does not extend through the connector 250. In either embodiment, the flow path from the tubing 272 to the lateral branch 26 may include the annular region around the tubing 264. Such annular region is isolated from the exterior by seal bore 278, seal bore 284, seal bore 268, and packer 288 and other packers and seal bores.
The lower end of the tubing 264 is sealably connected to the upper end of a pipe or tubing extension 266. The upper end of the pipe extension 266 may be a seal bore 268 into which the tubing 264 may be stabbed to provide a sealed connection. The pipe extension 266 itself is stabbed into a seal bore 270 at the upper end of the liner 262. In this manner, a sealed, continuous flow path is provided from the inner bore of the liner 262, through the pipe extension 266 and the tubing 264.
Note that the arrangement shown in
The upper end of the tubing 264, as well as the second tubing 272 that is in communication with the lateral branch connector 250, are communicatively coupled to a flow control assembly 274. The flow control assembly 274 controls the fluid flow from the multiple sources, in this case the lateral branch 26 and the lower main well bore section 260.
A connection assembly 280 is provided in the main well bore section 260 below the lateral branch junction to enable a sealed connection to the lateral branch template 252. The connection assembly 280 includes a housing 282 having a packer 286 on its outer surface to seal a space between the housing 282 and the inner surface of a casing 12. The upper end of the housing 282 includes a seal bore 284 to receive the lateral branch template 252. The connection assembly 280 also includes a packer 288 that is provided between the outer wall of the pipe extension 266 and the inner surface of the housing 282.
Referring to
Next, as shown in
After installation of the lateral branch template 252, the lateral branch connector 250 is next installed (as shown in FIG. 17C). The lateral branch connector 250 is engaged in the lateral branch template 252, which is described in greater detail above. The lower end of the lateral branch connector 250 is stabbed into the seal bore 255 of the liner 254.
As shown in
Optionally, a packer 802 (not shown in
The arrangement discussed in connection with
As shown in
Both the production bore 302 and the intervention bore 304 extends generally longitudinally along the template 308. In the illustrated embodiment, the production bore 302 is offset to one side of the template 308, while the intervention bore 304 is generally aligned with the main bore 22 to enable the running of an intervention tool through the intervention bore 304 into the main bore 22. An in-flow control device (such as the valve 202 in
The upper end of the production bore 302 in the template 308 leads to a radial port 312 that is in communication with a valve assembly 314. In one embodiment, the valve assembly 314 includes a sleeve valve 316 that is actuatable between an open position and a closed position. Optionally, the sleeve valve 316 can also be actuated to one or more intermediate choke positions. The sleeve valve 316 is connected to an operator mandrel 318 that is moveable by an actuator (not shown) of the valve assembly 314 in a longitudinal up and down direction. When the valve 316 is open, fluid can flow from the production bore 302 of the template 308 through the radial bore 312 and radial bore 320 of the valve assembly 314 into the inner bore 322 of the valve assembly 314. Fluid flow can then proceed up the upper main bore 38. Although the radial bores 312 and 320 are referred to in the singular, other embodiments may have plural radial bores 312 and 320 to provide a larger cross-sectional flow area.
When the valve 316 is closed, and the in-flow control device 310 is open, then fluid flows through the flow control device 202 in the lateral branch bore 26 into the template 308. Flow proceeds up the template 308 into the inner bore 322 of the valve assembly 314, and fluid continues up into the upper main bore 38.
Cross-sectional views of the junction assembly of
In one embodiment, the connector 300 also includes a pair of continuous rails 352 (similar to rail 126 in
As shown in
Referring to
To provide the desired flow control in the junction assembly, a tubing 406 extends through the template 404, with a packer or other sealing element 408 providing a seal between the external surface of the tubing 406 and protruding members 410 attached to casing 412. In an alternative embodiment, instead of protruding members 410 attached to the wall of the casing 412, the packer or other sealing element can have a wider outer diameter to engage the inner wall of the casing 412.
The tubing 406 is connected at its lower end to a valve 422, which controls the flow of fluids from the lower main bore 22 into the tubing 406. The upper end of the tubing 406 extends to a valve device 414 that is sealingly engaged to the inner wall of the casing 412. In one example, the valve device 414 includes a ball valve 416. Alternatively, the valve device 414 includes a flapper valve, a sleeve valve, or other type of valve.
To allow communication of fluids from the lateral branch 26, openings 420 (such as in the form of slots) are formed on the outer wall of the tubing 406. Flow from the lateral branch 26 enters the tubing 406 for communication to the well surface. To enable fluid flow from the lower main bore 22, the valve 422 is opened, as is the valve 416. Optionally, a flow control device in the lateral branch 26 can be closed to prevent commingling of fluids in the junction assembly. In another setting, the valve 422 can be closed and fluid flow from the lateral branch 26 is directed through the valve 416 into the upper main bore 38.
Referring to
In accordance with this embodiment, a diverter 514 is placed on the outside of the flow conduit 502 to enable intervention tools lowered down the flow conduit 504 to engage the diverter 514 so that the intervention tool is directed into the lateral branch 26. The diverter 514 can be integrally formed on the outer surface of the flow conduit 502, or alternatively, the diverter 514 is attached by rivets, screws, and the like, to the flow conduit 502. Use of a diverter 514 attached to the flow conduit 502 avoids the need for a separate diverter tool in the wellbore.
Referring to
While the invention has been disclosed with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover such modifications and variations as fall within the true spirit and scope of the invention.
This is a continuation-in-part of U.S. Ser. No. 09/789,187, filed Feb. 20, 2001, now U.S. Pat. No. 6,568,469 which is a continuation-in-part of U.S. Ser. No. 09/196,495, filed Nov. 19, 1998, now U.S. Pat. No. 6,209,648.
Number | Name | Date | Kind |
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5411082 | Kennedy | May 1995 | A |
5680901 | Gardes | Oct 1997 | A |
5918669 | Morris et al. | Jul 1999 | A |
5941308 | Malone et al. | Aug 1999 | A |
6079494 | Longbottom et al. | Jun 2000 | A |
Number | Date | Country |
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0786578 | Jan 1996 | EP |
2304764 | Sep 1997 | GB |
WO 0029713 | Nov 1998 | WO |
Number | Date | Country | |
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20020112857 A1 | Aug 2002 | US |
Number | Date | Country | |
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Parent | 09789187 | Feb 2001 | US |
Child | 10035681 | US | |
Parent | 09196495 | Nov 1998 | US |
Child | 09789187 | US |