Apparatus and method for transporting, deploying, and retrieving arrays having nodes interconnected by sections of cable

An apparatus and method for transporting, deploring, and retrieving an array is disclosed. The array has a plurality of nodes interconnected by sections of cable and can be transported, deployed, and retrieved with the apparatus and method of the present invention. The apparatus includes a plurality of first divisions and a plurality of second divisions. The first divisions have first portions or holders capable of individually accommodating the nodes. The second divisions are alternatingly positioned adjacent the first divisions. The second divisions have second portions or surfaces capable of individually accommodating the sections of cable. The first and second divisions can be integral portions of the apparatus, can be separate members positioned on the apparatus, or can be used with a standard cable drum. Preferably, the second divisions can be rotated relative to the first divisions to tightly wind and easily unwind the sections of cable.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is filed concurrently with U.S. patent application Ser. No. 10/266,903, entitled “Multiple Component Sensor Mechanism;” U.S. Provisional Patent Application Ser. No. 60/416,932, entitled “Clamp Mechanism for In-Well Seismic Sensor;” and U.S. patent application Ser. No. 10/266,716, entitled “In-Well Seismic Sensor Casing Coupling Using Natural Forces in Wells,” which contain related subject matter and are incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates generally to an apparatus and method for transporting, deploying, and retrieving an array having a plurality of nodes interconnected by sections of cable and, more particularly to an apparatus and method for transporting, deploying, and retrieving a pre-assembled fiber optic in-well seismic array having a plurality of fiber optic sensors, clamp mechanisms, and sections of cables between sensors.

BACKGROUND OF THE INVENTION

Arrays having a plurality of nodes interconnected by sections of cable exist in the art. Ocean bottom cables, umbilical cables, telecommunication cables, towed hydrophone arrays, and in-well seismic arrays are just some examples of arrays having a plurality of nodes interconnected by sections of cable. In general, the nodes can be fiber optic sensors, electrical sensors, hydrophones, geophones, or cable connectors, among numerous other devices. Difficulties are encountered when the sections of cable and the nodes are wound onto and unwound from a cable drum or other carrying device. Because the nodes may be larger and may be less flexible than the sections of cable, the nodes may form numerous bulges when winding the array on the drum or other carrying device. Consequently, the array cannot be uniformly wound or organized on the drum or carrying device, which leads to inefficient use of space and potential entanglement of the cable sections and nodes, among other problems. Furthermore, the nodes may be delicate or may require special protection. Therefore, pre-assembling the array and winding the array on the drum or other carrying device may not be possible, because the nodes must be transported under separate protection and assembled to the sections of cable on site.

It is therefore desirable to provide an apparatus and method for the transportation, deployment, and retrieval of a pre-assembled array having a plurality of nodes interconnected by sections of cable. The present invention is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.

SUMMARY OF THE INVENTION

An apparatus and method for transporting, deploying, and retrieving an array is disclosed. The array has a plurality of nodes interconnected by sections of cable. For example, the array can be an in-well seismic array having a plurality of seismic stations interconnected by sections of inter-nodal cable. The array can be pre-assembled and transported, deployed, and retrieved with the disclosed apparatus and method of the present invention. The apparatus includes a plurality of first divisions and a plurality of second divisions. The first divisions have first portions or holders capable of individually accommodating the nodes. The second divisions are alternatingly positioned between the first divisions. The second divisions have second portions or surfaces capable of individually accommodating the sections of cable. The first and second divisions can be integral portions of the apparatus, can be separate members positioned on the apparatus, or can be used with a standard cable drum. Preferably, the second divisions can be rotated relative to the first divisions to tightly wind and easily unwind the sections of cable.

DETAILED DESCRIPTION OF THE INVENTION

In the disclosure that follows, in the interest of clarity, not all features of actual implementations of an apparatus and method for transporting and installing an array are described in this disclosure. It will of course be appreciated that in the development of any such actual implementation, as in any such project, numerous engineering and design decisions must be made to achieve the developers' specific goals, e.g., compliance with mechanical and business related constraints, which will vary from one implementation to another. While attention must necessarily be paid to proper engineering and design practices for the environment in question, it should be appreciated that the development of an apparatus according to the present invention would nevertheless be a routine undertaking for those of skill in the art given the details provided by this disclosure.

Referring to the schematic illustration inFIG. 1, an array20is shown being deployed with an apparatus50according to the present invention. In the present example, the array20is a fiber optic in-well seismic array used in the exploration of a hydrocarbon reservoir. The array20has a plurality of nodes or sensors30interconnected by sections of cable40. The sensors30can include individual sensors or can include sensor assemblies having numerous sensors and other components. The array20is shown deployed in a well10, which has been drilled down to a subsurface production zone and is equipped for the production of petroleum effluents. Typically, the well10includes a casing12coupled with the surrounding formations by injected cement. The well10may be fifteen to twenty thousand feet or more in depth. Production tubing14can be lowered into the cased well10. The annulus16may be filled with a drilling fluid (not shown) having a high temperature and pressure, which can present an extremely corrosive and hostile environment.

During deployment, the array20is coupled to the production tubing14and is lowered to a desired depth in the well10, which may be thousands of feet. Once deployed in the well10, the sensors30are preferably coupled to the casing12for seismic sensing. Various techniques exist in the art to couple the sensors30to the casing12for seismic sensing. In the present example, the sensors30are initially coupled to the tubing14and are eventually coupled to the casing12using clamp mechanisms32. A preferred clamp mechanism for use with a multiple component sensor of the present invention is disclosed in U.S. Provisional Patent Application Ser. No. 60/416,932, which is filed concurrently herewith, is entitled “Clamp Mechanism for In-Well Seismic Station,” and is incorporated herein by reference in its entirety.

As is known in the art, seismology involves the detection of acoustic waves to determine the strata of geologic features, and hence the probable location of petroleum effluents. The sensors30are interconnected by the inter-nodal cables40to a source/sensing/data collection apparatus (not shown), which typically includes a demodulator and optical signal processing equipment (not shown). The inter-nodal cables40are typically ¼-inch diameter capillary tubes housing optical fibers between the sensors30and the source/sensing/data collection apparatus. The sensors30can include any of the various types of acoustic and/or pressure sensors known in the art.

A seismic generator (not shown) arranged at the surface or in another well is used to generate acoustic waves. Acoustic waves radiate from the source along direct paths and reflected paths through the various layers of earth. The seismic waves cause the surrounding earth layers to react, and the motion is detected by the sensors in the sensors30through the casing10coupled to the earth. Resulting signals are transmitted through the inter-nodal cable40to the source/sensing/data collection apparatus, which interrogates the sensors30. As is known in the art of fiber optic based seismic sensing, each sensor30can includes one or more fiber optic based sensors, such as fiber Bragg gratings (FBG's), that reflect a narrow wavelength band of light having a central wavelength. If each sensor30has a different reflection wavelength, the reflected signals may be easily detected using Wavelength Division Multiplexing (WDM) techniques. If the sensors have the same wavelength, reflected signals can be resolved in time using Time Division Multiplexing (TDM) techniques. Such multiplexing technologies and mixtures thereof are well known in the art.

When performing vertical seismic profiling, the sensors30of the array20are distributed over a known length, which can be as great as 5000 feet. Over the known length, the sensors30can be evenly spaced at desired intervals, such as every 10 to 20 feet, for providing a desired resolution. Accordingly, the fiber optic in-well seismic arrays20can include hundreds of sensors30and associated clamp mechanisms32. Because fiber optic connectors (not shown) on the inter-nodal cables40between the sensors30can generate signal loss and back reflection of the signal, the use of such connectors is preferably minimized or eliminated in the array20. The practical consequence of limiting the use of fiber optic connectors is that all or most of the sensors30must be spliced with the inter-nodal cables40before being transported to the well10.

Accordingly, the present invention is directed to an apparatus and method for efficiently and reliably transporting, deploying, and retrieving a pre-assembled array, such as the fiber optic in-well seismic array20depicted inFIG. 1. An embodiment of the apparatus50according to the present invention is illustrated inFIG. 1. The apparatus50includes a carrying device or body52having a plurality of first divisions54and a plurality of second divisions58. In one embodiment, the first and second divisions54and58can be integral portions of the body52. In a preferred embodiment, the first and second divisions54and58can be individual members alternatingly positioned on the body52.

As discussed above, one problem associated with arrays having a plurality of nodes interconnected by sections cable is the inability to neatly organize, wind, and unwind the array during deployment and retrieval. The first and second divisions54and58according to the present invention enable the array20to be neatly organized, wound, and unwound during deployment and retrieval. Consequently, the array20or major portions thereof can be pre-assembled and transported to the well, which can reduce deployment and retrieval time.

In particular, each of the first divisions54includes a portion or holder56for individually accommodating or holding a sensor30of the array20. Thus, the first divisions54can make room for the nodes30of the array20, can support the nodes30in a particular position, and/or can keep the nodes30from moving. The holders56can protect the sensors30during transport and can individually release and receive the sensors30during deployment and retrieval of the array20. As best described below, each holder56can also accommodate or hold a clamp mechanism32having the sensor30installed therein, which can greatly facilitate deployment at the well10.

In one embodiment, the holder56can merely be an outer surface of the first division54or can be a cavity defined in the first division54. Depending on the shapes and dimensions of nodes on an array, the holder56can be configured to accommodate or hold a particular node, sensor, clamp mechanism, or other device. In another embodiment, the holder56can be an extension, drawer, panel, clamp, or like structure for holding and releasing the node (i.e., sensor30and/or clamp mechanism32) or other device.

Each of the second divisions58individually accommodates or holds the internodal cable40between sensors30. The second divisions58keep the sections of cable40separate from the sensors30and can individually release and receive the sections of cable40during deployment and retrieval of the array20. Because the length of cable40between sensors30can vary on the array20or can vary from one array to another, the second divisions58can neatly accommodate or hold the different lengths of cable40. Thus, the second divisions54can make room for the sections of cable40of the array20, can support the sections of cable40in a particular position, or can keep the sections40from moving.

In one embodiment, the first and second divisions54and58can be fixedly connected to the body52. Rotation of the body52, therefore, can cause rotation of the first and second divisions54and58. Preferably, at least one of the divisions54or58is independently rotatable with respect to the other divisions. For example, the second divisions58for accommodating or holding the section of cable40are preferably individually rotatable relative to the first divisions54adjacent thereto. Having the second divisions58rotatable relative to the adjacent first divisions54can allow the sections of cable40to be tightly wound on the second divisions58when installing the array20on the apparatus50, as described in more detail below.

During deployment of the array20, equipment and methods known in the art can be used with the apparatus50to install the array20in the well10. For example, a sheave wheel60, a rotation mechanism62, and other equipment known in the art or installation personnel can be used. The body52can be positioned on the rotation mechanism62. Although shown vertically inFIG. 1, the body is preferably oriented horizontally on the rotation mechanism62so that any slack that may develop in the cable40will not interfere with operation of the apparatus50. When the body52is rotated by the mechanism62, the sensors30and inter-nodal cables40can be individually and sequentially fed from the divisions54and58and coupled to the tubing14using the clamp mechanisms32.

In one embodiment, the apparatus50can be an independent apparatus capable of being used with existing equipment for ocean bottom cables, telecommunication cables, umbilical cables, in-well sensors, such as pressure and temperature gauges, or towed hydrophone streamers, among other arrays. In another embodiment, the apparatus50can incorporate or be used in conjunction with a standard cable drum, which is a standard piece of equipment used with arrays.

Referring toFIG. 2, an embodiment of an apparatus100for transporting, deploying, and retrieving an array A is illustrated for use with a standard cable drum70. Being compatible with the cable drum70, the apparatus100can make use of existing spooling units, rotation tables, and other equipment associated with arrays. InFIG. 2, the apparatus100is depicted in a basic form to show the gross anatomy of the disclosed apparatus100. One of ordinary skill in the art will appreciate that the basic form can be altered without departing from the present invention.

The standard cable drum70typically includes a central portion or cross member72with first and second sidewalls74and76connected on the ends. The central portion72defines an internal bore78therethrough for mounting the drum70. For illustrative purposes, the apparatus100is shown only partially installed on the drum70, and the array A is only partially shown installed on the apparatus100.

The apparatus100includes first divisions110having portions or holders118for individually accommodating or holding the nodes30. The holders118can be made to accept various types of nodes N, including sensors, clamp mechanisms, or connectors, among other devices. For example, sensor/clamp assemblies30/32where the sensors30are installed on clamps32for an in-well seismic array, such as described above, can be transported together in the holders118, which can further reduce the time required to deploy the seismic array. The holders118simplify the handling of the nodes N and reduce the risk of damage to the nodes N during transport and installation.

The apparatus100also includes second divisions150for individually accommodating or holding the sections of cables C. The second divisions150assure that the sections of cable C between nodes N can separately fit onto the periphery of the members150between nodes N, which minimizes the risk of the cable C and nodes N becoming entangled. The second divisions150include first and second sidewalls152and154.

In the present embodiment, the first divisions110are individual members capable of being positioned on the central portion72of the drum70. The second divisions150are also individual members capable of being positioned on the central portion72of the drum70. For example, the first and second divisions110and150have holes (not shown) in their centers, allowing the divisions110and150to be positioned and rotated on the central portion72of the drum70. The first divisions110are placed on the drum70to store the pre-assembled nodes N. The second divisions150are placed adjacent the first divisions110on the drum70to accommodate the sections of cable C between nodes N.

In one embodiment of the present invention, the drum70can be modified to allow one or both of the sidewalls74or76of the drum70to be removable from the central portion72. In this way, the first and second divisions110and150can be easily positioned on and removed from the central portion72. Alternatively, and as disclosed in more detail below, the first and second divisions110and150can be comprised of two or more connectable sections (not shown) for mounting on the central portion72of the cable drum70when not modified.

In the present embodiment, both the first and second divisions110and150are rotatably disposed on the central portion72of the drum70. The apparatus100includes a plurality of locking members80and82to keep the divisions110and150from rotating on the central portion72or to keep them from rotating relative to one another. A first locking member80is a bolt or rod capable of being positioned through a hole (not shown) in the sidewall74of the drum70and in throughholes (not shown) in the first division110a. A number of second locking members82are capable of being positioned through the throughholes (not shown) in the first and second divisions110and150to prevent rotation of the divisions110and150relative to one another. An example of the through holes in the divisions can be seen inFIG. 3B, as element172. Such an arrangement of locking members80and82allows the divisions to be rotated in unison with the cable drum70, for example, when deploying the array A. In addition, such an arrangement of locking members80and82allows the divisions to be rotated relative to one another on the cable drum70, for example, when winding the array A on the apparatus100.

The apparatus100has the advantage of using an existing cable drum and other equipment associated with arrays and the advantage of allowing for flexibility in adjusting the length of cable C between nodes N. To position the seismic array A onto the apparatus100and drum70, the drum70is preferably positioned horizontally on a rotation member (not shown). One first division110ais then mounted on the central portion72immediately adjacent the sidewall74. An end node N1of the array A is then mounted in the holder118aof this first division110a. A second division150ais mounted adjacent the first division110a. Most of the section of cable C connected to the first node N1is then wound onto the second division150a. Another first division110bis then positioned adjacent the second division150aon the drum70. The next node N2of the array A is positioned in the holder118bof this next division110b. The section of cable C can be tightened about the intermediate second division150aby rotating the one or more of the divisions110a,110b, and150awith respect to each other. For example, the first division110amay be not locked in position, the cable40may be wound onto the second division150a, and the node N2may be positioned in the holder118of the next, first division110b. In this circumstance, the divisions110a–bcan be rotated relative to one another in opposite directions to tighten the cable on the second division150atherebetween.

When the cable C is sufficiently tight on the second division118a, the divisions110a,110band150acan be locked in position. In other words, the locking member80can be passed through the sidewall and into a throughhole in the first division110a, and a locking member82can be passed through aligned holes through the divisions110a, and150a. The same procedure can then be repeated for the remainder of the array A until all of the nodes N and sections of cable C are mounted onto the apparatus100and drum70. With the locking members80and82positioned though the divisions110and150and the sidewalls74and76, the wound array A can be locked into place with the sections of cable C neatly wound on the apparatus100.

Referring toFIGS. 3A–B, an embodiment of a first division110for use with an existing cable drum or other carrying device is illustrated in an end view and a cross-sectional view, respectively. The first division110includes a first section112and a second section114. The sections112and114of the first division110are preferably composed of a lightweight, inexpensive, and durable material, such as wood for example. The first and second sections112and114are connectable. When connected as shown inFIG. 3B, the first and second sections112and114define an central opening115to accommodate a central portion72of a cable drum70or other carrying device. Having the first and second divisions112and114connect together makes the first division110suitable for attaching to an existing cable drum without the need to modify the drum by removing the sidewalls74or76.

The first and second sections112and114can connect together with coupling or fastening mechanisms116known in the art, such as screws, bolts, brackets or other ordinary techniques. For example, the coupling or fastening mechanisms116can include long bolts passing laterally through the sections and having nuts connecting to the ends of the bolts to hold the sections112and114together. In an alternative example, the coupling or fastening mechanisms116can include an interconnecting plate being boltable to the sides of the sections112and114. Such coupling or fastening mechanisms116can allow for permanent or non-permanent coupling of the sections112and114. As one skilled in the art will recognize, the coupling or fastening mechanisms116for connecting the first and second sections112and114can constitute a number of mechanism or techniques known in the art. Of course, the first division110can also constitute an integrated apparatus without separate sections112and114.

The first division110can be used with a locking mechanism, such as a rod80described above, to stop rotation of the division110relative to adjacent divisions or to the drum. To facilitate this approach, the first division110includes a plurality of holes172circumscribing the central opening115.

One of the sections112defines a cavity118. In a preferred embodiment, a drawer120is movably positioned in the cavity118and is extendable therefrom. The extendable drawer120defines a holding area122formed by a bottom124and one or more sidewalls126. The holding area122can individually hold a node N of an array, such as an in-well sensor. In addition, the holding area122can be adapted and shaped to hold a clamp mechanism having the sensor installed therein. Preferably, the extendable drawer120has curved or contoured ends or guides127adjacent the holding area122to prevent entanglement or damage to the sections of cables C positioned adjacent thereto.

In the present embodiment, the extendable drawer120is connected to the first section112with a hinge128, enabling the drawer120to be pivoted out of the cavity118, as shown inFIG. 3B. The drawer120can be composed of wood, and the pin can be composed of steel, for example. The extendable drawer120pivots out of the cavity118in an opposite direction to the intended rotation R of the first division110when deploying the array A. In this way, as the first division110is rotated, the extendable drawer120can pivot and extend the node N substantially tangent to the rotation R. Thus, a node N connected to sections of cable C can be readily released from the extendable drawer120and first division110, for example, substantially parallel to the production pipe as it is deployed down the well. In an alternative embodiment to pivoting in the cavity118, the extendable drawer120can be slide in the cavity118. By sliding, the drawer120can extend from the cavity118and release the node N during rotation of the member110. Accordingly, the cavity118can include tracks or rails (not shown) on which the drawer120slides.

When the first division110is installed on a drum or other device and the node N is positioned in the extendable drawer120, the extendable drawer120can be kept in the cavity118by the connection of the node N to the cables C. In one embodiment, the first division110includes a lock or latch mechanism119to keep the extendable drawer120in the cavity118, which may be beneficial when the first division110is transported with the drum or other carrying device. For example, the lock or latch119can be a bolt lock, a clasp, or other method or techniques known in the art for locking a movable member to another member. Before installation, the lock or latch119can be undone, which will allow the extendable drawer120to extend during rotation of the member110.

The node N is preferably held within the drawer120by a releasable fastening mechanism or a temporary holding mechanism (not shown). For example, the drawer120can have a strap, a cover, a fastener, an adhesive, a clamp, a mounting block, a wedge, an appropriately shaped foam or plastic insert, or other method or technique known in the art for releasably fastening or temporarily holding a device on a surface or in a cavity. The fastener may need to be undone during installation of the array A to allow the node N to be released from the drawer120. Alternatively, the fastener may release the node N when a predetermined orientation of the drawer120is obtained or when the node N is subject to a predetermined force.

If the node N is a delicate sensor to be held in the drawer120, the drawer120preferably holds a transportation receptacle for the delicate sensor. A preferred transportation receptacle for the multiple component sensor mechanism incorporated herein is disclosed in U.S. patent application Ser. No. 10/266,903, which is filed concurrently herewith, is entitled “Multiple Component Sensor Mechanism,” and has been incorporated herein by reference in its entirety.

The dimensions of the first division110and the extendable drawer120can be designed to suit a number of nodes, such as sensors, clamp mechanisms, or other devices on arrays. In the illustrations ofFIGS. 3A–B, the first division110and extendable drawer120are depicted in a basic form to show the gross anatomy of the present invention. One of ordinary skill in the art will appreciate the basic forms can be altered without departing from the present invention. For example, the first division110can be configured to hold a number of sensors, which might be beneficial if the cables connecting the sensors at some point in the array are relatively short. In this circumstance, the short cable sections may need to be organized and stored with or in a manner similar to the sensors.

Moreover, although the use of a drawer120is preferred for the reasons previously set forth, a drawer120may not be necessary in a commercial embodiment. For example, cavity118could be configured to directly hold the nodes in the various manners described without the added complication of an extendable drawer120. Furthermore, a cavity118is not strictly required either, as the node could be affixed by many of the known methods and techniques to the outside surface of the first division110.

Referring toFIGS. 4A–B, an embodiment of a second division or member150for use with an existing cable drum or other carrying device is illustrated in an end view and a cross-sectional view, respectively. The second division150is preferably used with the first division110ofFIGS. 3A–Band is preferably used with an existing, unmodified cable drum.

The second division150includes a first section152and a second section154being connectable together. The sections152and154can connect together by one or more coupling or fastening mechanisms156known in the art. When the first and second section152and154are connected together, the second division150defines a central opening155to accommodate a central portion of the drum or other carrying device. As with the first division110, the second division150can also be integrated as a single piece.

The second division150is used for coiling the length of cable (not shown) between nodes of the array. The length of cable can typically be between 10 and 20 feet between sensors for in-well seismic sensing, for example. The second division150has a surface158for accommodating or holding the section of cable and has first and second sidewalls160and162for keeping the cable on the surface158. The sidewalls160and162extend beyond the surface158to assure that the cable remains on the surface158during winding and unwinding. In the present embodiment, the sidewalls160and162define a plurality of splines161for allowing the sections of cable to easily pass to and from the second division150. As with the first division110, the second division120contains through holes174to permit locking by a bolt80or other similar device.

The width and diameter of the second division150and the height of the splines161can be designed to best suit the length of cable to be stored thereon. As noted above, the length of cable between seismic stations can differ along an array, but can typically be 10 to 20 feet. To accommodate substantially larger length of cable or to better use the available space on the cable drum, second divisions150of greater widths or greater depths, for example, can be used or multiple second divisions150can be positioned adjacent one another.

Referring toFIGS. 5A–B, a division or member180of the disclosed apparatus is illustrated in an end view and a side view, respectively. The division180inFIGS. 5A–Bis illustrated generically for clarity, but it is understood that the division180can be a first or second division as described above and can include sidewalls (not shown), for example. The division180includes first and second sections182and184connected together about a central or cross member72of a cable drum (not shown). The first and second sections182and184can be made of wood or other material. Each section182and184includes a semi-cylindrical member183and185, which can be composed of metal, for example. When the sections182and184are connected together as shown inFIG. 5B, the semi-cylindrical members define a cylindrical opening186disposed about the central portion72.

The division180includes an alternative embodiment of a locking mechanism190. The locking mechanism190uses the principle of a set screw known in the art to lock the division180on the central portion72. A pocket or access192can be defined in the side of the division. A bolt192is threaded into a threaded aperture196defined in the semi-cylindrical member183. When tightened, the bolt192engages the central portion72and to keep the division180from rotating about the central portion72. The recess192allows adjacent divisions to be positioned closely adjacent one another; however, it is understood that this is not strictly necessary. In addition, it is understood that more than one locking mechanisms190can be used for the division180.

Referring toFIGS. 6A–9D, another embodiment of a transportation, deployment, and retrieval apparatus200according to the present invention is illustrated. InFIGS. 6A–B, the apparatus200is illustrated in a front view and a side view, respectively. The apparatus200in the present embodiment is preferably used with an in-well seismic array having sensors30installed in clamp mechanisms32, as described above.

The apparatus200includes a carrying device or body202having a central portion or cross member204. The body202can be composed of metal or wood, for example. The cross member204can be a steel rod having a length of approximately 53-inches, for example. The body202is only schematically shown for the purposes of clarity and can include additional components. For example, the body202can include components allowing the body to be lifted by a crane or forklift and can include additional components for protecting the apparatus200and array during transport. It is understood that the body202and cross member204are capable of supporting the weight of the apparatus200and array.

The apparatus200includes a plurality of first divisions or members210for individually accommodating or holding the sensor/clamp assemblies30/32, having the sensors30mounted in the clamp mechanisms32, such as described herein. The apparatus200also includes a plurality of second divisions or members250for individually accommodating or holding the inter-nodal cables40connected between sensor/clamp assemblies30/32. In the present embodiment, the apparatus200can accommodate five of the first divisions210and five of the second divisions250having the sensor/clamp assemblies30/32and cables40pre-assembled thereon. Therefore, for a seismic array requiring 50 to 100 sensors, ten to twenty such apparatus200may be required. If necessary or desirable to concatenate several apparatuses containing mounted arrays at the well site, the cables could be coupled at the side by numerous fiber optic connectors or coupling techniques. Alternatively, the apparatus200can be designed or lengthened to hold more sensors, clamp mechanisms, and sections of cable so that the use of multiple apparatuses is unnecessary.

In this embodiment, the first division210, which is described in more detail inFIGS. 7A–C, includes a frame212, a holder220, and arms or guides230. The holder220is connected to the frame212and supports the sensor/clamp assembly30/32. The guides230are also connected to the frame212adjacent the holder220. The guides230support the sections of cable40connected to the sensor/clamp assembly30/32. The second division250, which is described in more detail inFIGS. 8A–B, includes a central disk252and sidewalls254and256. The central disk252has a surface258for individually accommodating or holding the sections of cable40.

As best shown inFIG. 6A, the first and second divisions210and250are alternatingly positioned on the cross member204and are rotatably disposed thereon. As best shown inFIG. 6B, the first divisions210each include a locking mechanism270capable of engaging holes272on the second divisions250so that adjacent first and second divisions210and250can be prevented from rotating relative to one another.

Referring toFIGS. 7A–C, the first division210of the apparatus200is illustrated in a partially exposed side view, a front view, and a cross-sectional view, respectively. Frame212of the first division210is preferably square and is composed of four walls214and two panels216. The four walls214can be composed of wood members measuring approximately 150-mm by 50-mm. The panels216can be composed of 13-mm plywood sheets. The walls214and panels216of the frame214can be attached together using nails, screws, or other methods or techniques known in the art. Each of the panels216defines a central opening218for passage of the cross member204discussed above. The central openings218are approximately 77-mm in diameter.

In the present embodiment, the holder220is attached to the frame212by a hinge222, which allows the holder220to be rotated away from the frame212, although this is not strictly necessary for use with an in-well seismic array having sensors installed in clamp mechanisms. A lock or latch224on the other end can be used to keep the holder220adjacent the frame212.

The holder220has a mounting surface226, which can be configured to hold the sensor/clamp assembly30/32. For illustrative purposes, the sensor/clamp assembly30/32is shown inFIG. 7Aand is not shown inFIG. 7B. The mounting surface226can include supports228and releasable fastening mechanisms or a temporary holding mechanisms229, such as a belt or strap, to keep the sensor/clamp assembly30/32on the mounting surface226. The in-well sensor/clamp assemblies30/32described herein can weigh between 20 and 40-kg. Therefore, the fastener229must be capable of adequately holding such a weight to the mounting surface226. It is understood that the mounting surface226of the holder220can be configured to hold a number of devices or mechanisms depending on the type of array to be used with the apparatus200of the present invention.

The cable guides230extend from the frame212on both ends of the holder220. Each cable guide230has a supporting arm232and a curved end piece234. The guides230project approximately 380-mm from the frame212with the curved end pieces234making up approximately 90-mm of that length. The curved end pieces234also define a radius of approximately 15-mm, which facilitates a 16-inch radial bend for the standard ¼-inch fiber optic inter-nodal cable40used for in-well sensing. Smaller radii may damage the cable.

The cable guides230can define a channel (not shown) adjacent the curved end pieces234to prevent entanglement of the cable. In addition, breakable fasteners, such as bands, can be used on the guides230to temporarily hold the cable and prevent inadvertent removal of the cable from the guides230during assembly. One of ordinary skill in the art will recognize that the cable guides230can be altered to accommodate a particular cable other than that disclosed herein, which might be necessary or beneficial for cables of differing flexibility, for example.

Referring toFIGS. 8A–B, the second division250of the apparatus200is illustrated in a side view and an end view, respectively. The second division250includes a central disk252having sidewalls254and256attached thereto. The sidewalls254and256define a plurality of splines258, which are preferably spaced about every 5-degrees around the circumference of the second division250for allowing cable to pass between divisions. The splines258preferably project approximately 25-mm above the circumference of the central disk252.

In the present embodiment, the central disk252can be composed of several sheets of plywood attached together by methods known in the art. The central disk252can be approximately 1625-mm in diameter and approximately 39-mm thick. The sidewalls254and256can be composed of 13-mm plywood. The second division250defines a central opening251approximately 76-mm in diameter through the sidewalls254and256and the central disk252. One of ordinary skill in the art will appreciate that the dimensions of the second division250can be increased or decreased depending on a number of variables, including the amount of cable and thickness of cable to be wound thereon. The second division250defines a plurality of holes272on one or both sides. The holes272are preferably approximately 13-mm in diameter, disposed at a radius R of approximately 435-mm from the center of the second division250, and positioned approximately every 5-degrees.

Referring toFIGS. 9A–D, the apparatus200is illustrated in stages of deploying a seismic array in a well10. InFIG. 9A, the apparatus200is shown in a side view positioned adjacent the well10. A clamp mechanism32with an installed sensor30is held on the holder220of the first division210of the apparatus200. As disclosed above, the sensor/clamp assembly30/32can be held, attached, or fastened to the holder220by a number of methods and techniques known in the art. This sensor/clamp assembly30/32represents the first seismic station for the in-well seismic array. An inter-nodal cable40is connected to the sensor/clamp assembly30/32and is wound about an adjacent second division250.

The adjacent divisions210and250are initially locked together. For example, the locking bolt270on the first division210engages one of the holes272on the second division250. Numerous other first and second divisions (not shown) are alternatingly arranged on the apparatus200. In the discussion that follows, only the deployment of this first sensor/clamp assembly30/32will be described. It is understood that the steps disclosed below can be substantially the same for other sensor/clamp assemblies on the apparatus200. Moreover, description of typical equipment and activities otherwise normally present at in-well installation are omitted for clarity.

Referring toFIG. 9B, a locking member or bar300is attached to the body202and cable guide230of the first division210. The locking member300can be attached using bolts or other methods known in the art. The locking member300prevents the first division210from rotating about the cross member204. The locking mechanism270on the first division210is then disengaged from the hole272defined in the adjacent second division250. With the adjacent members210and250unlocked, the second division250can be rotated relative to the first division210to unwind the cable40connected to the sensor/clamp assembly30/32. To unwind cable from the adjacent second division, the numerous other first and second divisions (not shown) of the apparatus200remained locked together and are rotated along with the adjacent second division250.

In contrast to embodiments disclosed above, it should be noted that the extendable feature of the holder220is not used, because the sensor30is installed in the clamp mechanism32. Therefore, it is undesirable to stress the sections of cable40by freely releasing the sensor/clamp assembly30/32by extending the holder220during rotation of the first division210. Use of the extendable feature of the holder220may be used for releasing a sensor, assembly, connector, or other device on the array that is smaller than the sensor/clamp assembly30/32described herein. In further contrast to embodiments disclosed above, the first division210is locked in place using the locking member300to allow the sensor/clamp assembly30/32to be dismounted and moved toward the production tubing14. Locking the first division210may not be necessary for releasing a sensor, assembly, connector, or other device on the array that is smaller than the sensor/clamp assembly30/32described herein.

Referring toFIG. 9C, a catching member310having a base arm312and a pivoting arm or tray314is attached to the well head11. The pivoting arm314is pivoted to meet and rest on the locking member300. The sensor/clamp assembly30/32is unattached or unfastened from the holder220. The second division250is rotated in direction R to unwind the cable40connected to the sensor/clamp assembly30/32. The sensor/clamp assembly30/32is guided down the locking member300to the pivoting arm312. The pivoting arm312includes a stop316for holding the sensor/clamp assembly30/32. A standard 16-inch cannon anchor clamp34is made ready for coupling the sensor/clamp assembly30/32to the production tubing14.

Referring toFIG. 9D, the pivoting arm314holding the sensor/clamp assembly30/32is rotated adjacent the production tubing14so that the sensor/clamp assembly30/32is held vertically. A sheave wheel64or similar device known in the art is used to unwind the cable40from the second division250and to position the cable40adjacent the production tubing14. Lower and upper anchor clamps34and36hold the sensor/clamp assembly30/32and cable40to the production tubing14. The base member312of the catching mechanism310has a sufficient clearance and height to allow the lower clamp34to be attached between the well head11and the end of the clamp mechanism50.

Once the sensor/clamp assembly30/32is coupled to the production tubing14, the catching member310is moved away from the well head11. The production tubing14is lowered, moving the sensor/clamp assembly30/32into the well10. The sheave wheel64is rotated to feed the cable40from the second division250into the well10. Additional cable clamps (not shown) can be used to attach the length of cable40between the first sensor/clamp assembly30/32and the next assembly (not shown) on the apparatus200. The above steps can then be repeated to deploy an entire array of sensor/clamp assemblies interconnected by sections of cable40. In addition, the above steps can be reversed to retrieve the sensor/clamp assemblies30/32and sections of cable40of the array from the well10and neatly organize and hold the array on the apparatus200. As noted above, however, to tightly wind the cable40onto the second divisions when retrieving the array requires that the divisions be rotated in relation to one another.

Although the embodiments disclosed herein have been described for use with a fiber optic in-well seismic array, one of ordinary skill in the art will appreciate that the present invention can be used with a number of arrays having a plurality of nodes interconnected by sections of cable and can be used for other applications beyond in-well seismic sensing installations. For example, the disclosed apparatus can be used to transport, deploy, and retrieve geophysical streamer cables, hydrophone and thermister arrays, ocean bottom cables, telecommunication cables, subsea cables, umbilical cables, towed hydrophone arrays, or other arrays. These arrays and applications may suffer from many of the same problems associated with in-well seismic arrays. Namely, these applications may require numerous nodes. Consequently, for these applications, it may also be beneficial to pre-assemble the entire array or portions thereof before transportation to a site.

Furthermore, while it is beneficial that the first divisions and the second divisions be rotatably coupled to the body of the apparatus, and rotatable with respect to each other, this is not strictly necessary in all applications. Thus, the first divisions and the second divisions, or either of these individually, can be rigidly coupled to the body (e.g., the cross members) of the apparatus. When such an embodiment is used, it will generally be helpful if some mechanism, such as a rotation mechanism (FIG. 1, element62), is used to turn the apparatus at the well site, although the apparatus can also simply be allowed to freely rotate (e.g., on a rotatable plate or stake) as the array is deployed or retrieved.

Moreover, an embodiment in which the first and second divisions are not rotatable may be particularly useful for mere transportation purposes as opposed to deployment or retrieval. Indeed, in this rigidly coupled embodiment, the first and second divisions do not need to constitute separate components, but instead could comprise an integral component, or different sections of the same component, and “divisions” as used in this disclosure should not necessarily be understood to imply separate components.

It is intended that the invention include all such modifications and alterations to the full extent that they come within the scope of the following claims or the equivalents thereof.