US 20050183862 A1
A method and apparatus are provided for installing control lines and pipe into a well. The pipe-holding spider that is normally mounted on the rig floor is supportably retained in a vertically movable retainer. The retainer is adapted for controllably elevating the spider above the rig floor when the pipe slips within the spider are not engaged with the outer surface of the pipe string, thereby providing personnel access to a portion of the length of the pipe string below the elevated spider and above the rig floor. Personnel are provided with access to the pipe string for applying a fastener to secure the control line to the pipe string.
1. An apparatus for installing a control line and a pipe string in a well comprising a retainer for reciprocating a spider.
2. The apparatus of
3. The apparatus of
4. The apparatus of
5. An apparatus for installing a control line and pipe string in a well comprising a jack for controllably elevating a spider to a raised position above a rig floor.
6. The apparatus of
7. The apparatus of
8. The apparatus of
9. A method of installing control line and pipe in a well comprising controllably raising a spider to a raised position above a rig floor.
10. The method of
11. The method of
12. The method of
13. The method of
This is a continuation of application Ser. No. 10/278,718 filed Oct. 23, 2002.
1. Field of the Invention
The present invention relates to a method and apparatus for installing pipe and control line in a well. More specifically, the present invention relates to a method and apparatus for installing control lines secured to a string of pipe as the pipe is being made up and run into a well.
2. Background of the Related Art
Oil and gas wells may be equipped with control lines for electrically, hydraulically or optically linking various downhole devices to the surface. Control lines may be used to receive data from downhole instruments and to selectively operate from the surface downhole devices such as valves, switches, sensors, relays or other devices. One use of control lines is to open, close or adjust downhole valves in order to selectively produce or isolate formations at locations deep in the well. A control line may transmit downhole data to the surface and communicate commands to the same or other downhole devices. The control line may comprise conductive wires or cables for electrically controlling downhole devices, fibers for optically controlling downhole devices, or small-diameter tubing for hydraulically controlling downhole devices. Control lines are generally of a small diameter relative to the diameter of the pipe string to which they are secured, and are generally between 0.5 and 6 cm. in diameter. Control lines are generally secured along the length of the outer surface of a pipe string, generally parallel to the center axis of the bore of the pipe string. Continuous control lines are secured to the pipe string and installed in the well as joints of metal pipe are made up into a pipe string and run into a well. Control lines secured to pipe string are subject to being damaged and useless if pinched or crushed, by pipe slips used to grip and support the pipe string while it is being made up and run into the well.
The spider is a device used on a drilling or workover rig for gripping and supporting the pipe string as joints of pipe are made up into the pipe string. The spider has an interior bore, generally aligned with the pipe string, through which the pipe string passes. The spider has a circumferential arrangement of radially inwardly movable pipe slips disposed around the pipe string and within the internal bore. The pipe slips move radially inwardly to circumferentially grip the outer surface of the pipe string and support the pipe string in the well when the pipe string is not supported by the elevator. It is important that the pipe slips in the spider uniformly engage and grip the pipe string in order to prevent crushing or damaging the pipe making up the pipe string. Each pipe slip within the internal bore of the spider applies a force radially inwardly against the outer surface of the pipe string. It is important that the pipe slips are concave in order to contact the pipe over as large an interval as possible in order to minimize the localized stress imposed on the pipe by the pipe slips.
If a control line becomes pinched or trapped between the pipe slips of the spider and the outer surface of the pipe string, or if a control line is pinched between adjacent segments of the pipe slips as they move radially inwardly to contact the pipe string, the control line may be damaged and surface control of downhole devices may be lost or impaired. It is important that the method used to secure control lines to the pipe string be designed to prevent control line damage.
One method of installing continuous control lines as the pipe string is made up and run into the well requires that the control lines extend along the portion of the pipe string where the pipe string is held in the internal bore of the spider. A control line is circumferentially positioned along the length of the outer surface of the pipe string to coincide with a gap or recess formed in the radially outwardly disposed portion of the pipe slips and sized to accommodate the control line. This method is satisfactory for a single control line or for multiple control lines that are flexible and pliable enough to be bundled together using an arrangement of positioning arms and control line guides to redirect control lines to the desired generally parallel configuration to be received within the gap or recess. However, this method is unsatisfactory for applications requiring multiple control lines being unspooled and fed from more than one location adjacent to the spider where the control lines are more stiff or otherwise resistant to being redirected and positioned using positioning arms and guides. Also, the gap or recess formed in the radially outwardly disposed portion of the pipe slips is of limited size and is insufficient to accommodate multiple control lines required for controlling multiple downhole devices.
In many installations, it is desirable to secure multiple control lines along the length of the outer surface of the pipe string in order to allow surface control of multiple downhole devices. Multiple control lines are especially useful in deep offshore wells that penetrate multiple formations. Existing designs may require four or more control lines for each string of pipe that is run into the well. Multiple control lines are most efficiently made, stored, transported and installed in bundles comprising control lines coupled together in a generally parallel, side-by-side configuration. Multiple control lines require larger clamps to secure the bundle along the length of the outer surface of the pipe string.
A method has been developed for securing control lines to a pipe string as the pipe string is made up and run into a well. U.S. Pat. No. 6,131,664 (“the '664 patent”) is directed to using an elevated work platform constructed on the rig floor. The work platform is equipped with hydraulic tongs for making up the pipe string, and an opening above the well in the floor of the work platform that is generally aligned with the well and with an opening in the rig floor beneath the work platform. The work platform disclosed in the '664 patent supports the spider and, when the pipe string is supported by the spider, the work platform must support the weight of entire pipe string. This requires the work platform to be built to support 200 tons or more. The work platform described in the '664 patent also requires sufficient work area for rig personnel to use the tongs to make up joints of pipe that are lowered and aligned in position above the pipe string to be threadably made up into the pipe string.
The '664 patent discloses that control lines are provided to the pipe string from a separate work area maintained on the rig floor and below the level of the work platform. The control lines are stored on and continuously provided from spools located lateral to the pipe string and adjacent to the opening in the rig floor. Clamps are installed by rig personnel working in the work area beneath the work platform to secure the control lines to the pipe string.
The problem with the method and apparatus for installing control lines described in the '664 patent is that the work platform must be extremely structurally robust to support the enormous weight of the entire pipe string, the control line, the spider, and the rig personnel making up the pipe string. The erection of the work platform consumes a large amount of rig time during which no progress is made in completing the well. After the control lines and pipe string are run into the well, the work platform must be removed from the rig floor, thus consuming additional rig time. Another problem with the method and apparatus disclosed in the '664 patent is that rig personnel working on the elevated work platform are dangerously impaired from escaping well blowout or other a well control situation.
What is needed is a method of safely securing control lines to a pipe string as the pipe string is being made up and run into a well. What is needed is a method of securing control lines to a pipe string that does not require the erection, removal or use of a special work platform for providing a work area for rig personnel that is separate from the rig floor. What is needed is a method of securing control lines to a pipe string as it is being made up and run in a well that eliminates the need for an elevated work platform strong enough to support the entire pipe string. What is needed is a method of securing control lines along the length of a pipe string as it is being made up and run in a well that eliminates obstructions to escape routes to be used by rig personnel in the event of a well blowout or other well control situation. What is needed is a method and an apparatus that enables the safe and inexpensive installation of control lines that are secured to a pipe string as it is being made up and run into a well.
The method and apparatus of the present invention allows one or more control lines to be secured along the length of a pipe string as the pipe string is being made up and run into a well. The method and apparatus of the present invention allows control lines to be secured to a pipe string above the rig floor and below the spider, but eliminates the need for an elevated work platform strong enough to support the enormous weight of the pipe string. The method and apparatus of the present invention improves rig safety by preventing impairment of escape routes on the rig floor.
In the method and apparatus of the present invention, the spider is received within and supportable by a vertically reciprocating retainer. The retainer is adapted to distribute the load on the spider to structural components in or under the rig floor when the pipe string is supported by the spider, and to vertically displace and support the spider when the spider is disengaged from the pipe string and the weight of the pipe string is supported by the elevator. The disengaged spider may be controllably elevated using the retainer to support the spider at a distance above the rig floor to permit rig personnel access to the outer surface of the portion of the pipe string located below the elevated spider and above the rig floor. Access to the outer portion of the pipe string below the spider and above the rig floor permits rig personnel to install fasteners to secure control lines to the pipe string.
Control lines are provided to the pipe string from spools located on or near the rig floor and generally lateral to the pipe string. Optionally, control lines are routed or threaded over roller guides in the retainer to strategically align the control lines along the length of the pipe string so that the control lines can be secured to the pipe string. Control lines are secured to the pipe string with fasteners, such as clamps, sleeves, bands, clips or other fasteners and installed by rig personnel working beneath the elevated spider, but in the same area of the rig floor used by rig personnel to operate the tongs and to make up joints of pipe into the pipe string. Control lines may be secured along the outer surface of the pipe string at any radial or circumferential location without regard to the points of contact between the outer surface of the pipe string and the pipe slips within the internal bore of the spider. Additionally, fasteners used to secure control lines to the pipe string may be designed independent of restrictions imposed by the size or configuration of the internal bore of the spider.
The foregoing, as well as other, objects, features, and advantages of the present invention will be more fully appreciated and understood by reference to the following drawings, specification and claims.
Wells are generally drilled deep into the earth's crust to establish fluid communication between the surface and sub-surface geologic formations containing naturally occurring hydrocarbon deposits, such as oil or gas. A well provides a fluid conduit allowing subsurface deposits of oil and gas to be produced at the surface. It is common for a drilled borehole to penetrate a plurality of formations. Formations may contain hydrocarbons or other fluids of different compositions and at different pressures than the hydrocarbons and fluids contained in other formations. Formations may also contain water (aquifers), brine, hydrogen sulfide gas and other materials that may be undesirable.
A drilled borehole is completed into a well by circulating cement into the annulus between the wall of the drilled borehole and the outer surface of a pipe string called casing to form a cement liner. The cement hardens to isolate penetrated formations from flowing into the well and to the surface. Once a borehole is drilled and completed, decisions are made as to which of the penetrated formations to selectively produce. A perforating tool is used to cut a hole through the casing and the cement liner to selectively establish fluid communication between the targeted formation and the surface. Once a formation is perforated, the well may be produced to (pressure) depletion, until it “waters out” by increasing water content, or both. Once a formation is depleted or watered out, it may be desirable to intervene in the well to alter or isolate the formation so that other formations may be perforated and produced without the production being burdened by fluid losses into depleted formations or by water intrusion from watered out formations. Intervention is generally performed by wire line unit (WLU) workover, coiled tubing unit (CTU) workover or by a conventional workover rig. A WLU or CTU workover is performed by lowering an instrument or tool into the well using a specialized rig having a long spooled wire line or tubing for connecting or controlling the downhole instrument or tool from the surface. The conventional workover rig generally requires that all production tubing be removed from the well so that tools or instruments may be run into the well on a work string.
If the depleted or watered-out formations lower in the well than the formation, the depleted or watered-out formation may be isolated from the well by using one of the three conventional intervention techniques described above. In a conventional intervention workover, material such as cement or sand may be deposited into the bottom of the well to form a plug to seal off the perforations in the depleted or watered-out formation, and to thereby isolate the depleted or watered-out formation from the new formation located above. Once a sand or cement plug is in place, another workover may be required to later remove it. Packers are tools that can be installed in a well during a workover to isolated, depleted or watered-out formations.
Conventional workovers to install or remove downhole plugs or packers are unnecessary if formations can be isolated or remotely controlled using downhole devices. Downhole devices, such as valves or chokes, may be installed in a pipe string as it is being made up and run into a well to enable the selective production, isolation or flow-control of fluids residing in the formations penetrated by a well. Surface-controlled downhole valves or chokes require continuous control lines that extend from the surface through the well to the depth at which the downhole devices are installed in the pipe string. Control lines must be installed as the pipe string is being made up and run into the well.
Continuous control lines are generally stored and transported to the rig location on spools. The spools of control line are generally mounted on a horizontal axle on or near the rig floor so that the control line may be easily and smoothly “fed” to the pipe string being fastened to the pipe string by reeling of the spool.
In the embodiment illustrated in
Personnel working on the rig floor 6 employ a hydraulically-powered set of tongs (not shown) to apply make-up torque to the pipe 13 and threadably couple it to the threaded coupling 12B to join pipe 13 into the pipe string 14. The rig floor 6 immediately adjacent to the retainer 10 provides a work area for rig personnel operating the hydraulic tong assembly to torque up the pipe string 14 by sequentially coupling additional joints of pipe 13.
In the preferred embodiment of the present invention shown in
The legs 40 that support and raise the retainer 10 are adapted for imparting generally vertical displacement of the retainer 10 and the spider 11 when the pipe slips 24 of the spider 11 are disengaged from the pipe string 14. In the preferred embodiment, the legs 40 comprise hydraulically telescoping members such as those generally used in hydraulic jacks and lifts. The hydraulic power for telescoping the legs 40 to raise the retainer (as shown in
In a preferred embodiment of the present invention shown in
As shown in
The fastener 34 used to secure the control lines 31 to the pipe string 14 may comprise a clamp, clip, spring, wire, strap, band or any fastener or other device that is suitable for securing a control line 31 to the outer surface of an elongated body such as a pipe string 14. Typically, the inside of the fastener 34 is adapted to fit the cylindrical outer surface of the pipe string 14 to which it is secured, and may be configured with one or more “pockets,” or circumferentially upset portions, to accommodate and to secure a control line 31 from circumferential and/or axial movement relative to the outer surface of the pipe string 14 to which the control line 31 is secured. Another mechanical fastener, such as a screw, clip, or a bolt and nut, may be employed to close and tighten the fastener 34 in place on the pipe string 14.
The mast or other structure (not shown) supporting the hydraulic tongs (not shown) used by rig personnel to make up the pipe string 14 may include a pivoting structure that allows the tongs to be pivoted or otherwise removed from the torqueing position. The mast may be pivoted away from the center axis of the pipe string 14 to be removed from the work area in order to prevent interference between the tongs and the retainer 10 as the retainer 10 is moved from the floor position to the raised position shown in
The roller guides 42 and 44 of the may be adapted for controllably imparting a predetermined direction or path to change the position of the control lines 31 relative to the pipe string 14. It may be appreciated that hydraulic, pneumatic or electrical assemblies may be employed for powering or moving the roller guides or other components of the invention. The control line spool (not shown) and the roller guides 42 and 44 may be adapted for applying a tensioning force to the control lines 31 and to prevent inadvertent over-reeling from the control line spools.
When the control line 31 comprises a bundle of control lines secured one to the others, the control line bundle may be more stiff and inflexible than a single control line 31. The roller guides 42 and 44 may be adapted to assist in bending and redirecting the control line bundle into a parallel position longitudinally along the outer surface of the pipe string 14 suitable for application of a fastener for securing the bundle to the pipe string 14.
While a preferred form of the present invention has been described herein, various modifications of the apparatus and method of the invention may be made without departing from the spirit and scope of the invention, which is more fully defined in the following claims.