Apparatus, system and method for treatment of an electric submersible pump power cable
10513785 ยท 2019-12-24
Assignee
Inventors
- Terry L. Glasscock (Vinita, OK, US)
- Peter J. Kneip (Cody, WY, US)
- Thomas John Gottschalk (Houston, TX, US)
- Brent Keith Kashwer (Broken Arrow, OK, US)
Cpc classification
E21B43/128
FIXED CONSTRUCTIONS
B65H75/00
PERFORMING OPERATIONS; TRANSPORTING
B08B3/10
PERFORMING OPERATIONS; TRANSPORTING
International classification
B65H75/00
PERFORMING OPERATIONS; TRANSPORTING
E21B43/12
FIXED CONSTRUCTIONS
B08B3/10
PERFORMING OPERATIONS; TRANSPORTING
B08B3/02
PERFORMING OPERATIONS; TRANSPORTING
Abstract
An apparatus, system and method for treatment of an electric submersible pump (ESP) power cable is described. A method of treating an ESP power cable includes wrapping an ESP power cable around a reel as the cable is removed from a production well to form cable layers, supporting the cable-wrapped reel horizontally above a tank, the reel supported on a shaft extending between actuatable support members, pumping treatment fluid into the tank, lowering the cable-wrapped reel partially into the tank by activating the actuatable support members such that a lower portion of the reel is submerged in the treatment fluid and an inner diameter of the cable-wrapped reel is fluidly coupled to the treatment fluid, rotating the reel around its central axis such that each portion of an outermost layer of the cable is submerged in the treatment fluid at least once to coat the ESP power cable.
Claims
1. A method of treating an electric submersible pump (ESP) power cable, the method comprising: supporting a reel horizontally above a tank on a shaft that extends between a pair of telescoping support members, the reel comprising: a tubular drum comprising an inner surface and an outer surface, the inner surface having apertures extending between the inner surface and the outer surface, the tubular drum comprising a pair of flanged open ends extending from the outer surface of the tubular drum to an outer circumference of the reel, the shaft extending through a central axis of the tubular drum and the pair of flanged open ends, and the ESP power cable wrapped around the outer surface of the tubular drum to form a plurality of ESP power cable wraps, wherein the inner surface partially encloses a hollow, the hollow having at least one open end, the inner surface positioned radially outward a minimum distance from the central axis of the reel so that when no more than one third of the height of the reel measured from the outer circumference and perpendicular to the central axis of the tubular drum is lowered into a treatment fluid, the hollow is fluidly coupled with the treatment fluid, allowing the treatment fluid to enter the hollow, pass through one or more of the apertures to the outer surface and to come into contact with the ESP power cable; retracting the pair of telescoping support members to lower the plurality of ESP power cable wraps partially into the tank such that a lower portion of the ESP power cable wraps is submerged in the treatment fluid and the inner surface of the tubular drum is fluidly coupled to the treatment fluid in the tank through the pair of flanged open ends; rotating the reel around the shaft such that a circumferential portion of each individual wrap the plurality of the ESP power cable wraps encircling the outer surface of the tubular drum is submerged in the treatment fluid at any given time and when no more than one third of the height of the reel measured from the outer circumference is submerged into the treatment fluid; and coating inner wrappings of the plurality of ESP power cable wraps with the treatment fluid when the treatment fluid flows through vents in flanges of the pair of open flanged ends and through the apertures as the reel is rotated.
2. The method of claim 1, wherein the treatment fluid is one of rust remover or rust inhibitor.
3. The method of claim 1, wherein the treatment fluid is rust remover, the rust remover is drained from the tank and then the retracting and rotating are repeated with a rust inhibitor as a second treatment fluid.
4. The method of claim 1, further comprising: lifting the coated ESP power cable out of the tank by extending the pair of telescoping support members; and draining the treatment fluid from the tank to a treatment fluid storage container.
5. The method of claim 1, wherein rotating the reel comprises successively and repeatedly submerging each circumferential portion of the ESP power cable wraps in the treatment fluid.
6. The method of claim 1, wherein the ESP power cable comprises armor surrounding insulated conductors, and further comprising coating the armor of an innermost wrap of the ESP power cable wraps with the treatment fluid through the apertures in the tubular drum.
7. The method of claim 1, wherein the reel is rotated by a bull gear drive.
8. The method of claim 1, further comprising locking an end of the shaft into a cradle coupled to one telescoping support member of the pair of telescoping support members with a locking bar.
9. The method of claim 1, further comprising straightening the flanges of the pair of open flanged ends of the reel before supporting the reel above the tank.
10. The method of claim 1, further comprising storing the ESP power cable so coated for a period of time on the reel, and deploying the ESP power cable into a production well by unwinding it from the reel.
11. The method of claim 1, wherein the ESP power cable wrapped around the outer surface of the tubular drum is between 4000 and 12,000 feet long.
12. The method of claim 1, wherein the ESP power cable wrapped around the outer surface of the tubular drum weights up to 9 tons.
13. The method of claim 1, wherein the ESP power cable includes between two and twenty layers of cable wrapped around the outer surface of the tubular drum.
14. The method of claim 1, wherein the reel has a seventy-eight inch diameter measured perpendicular to the central axis.
15. The method of claim 1, wherein the reel has a ninety-six inch diameter measured perpendicular to the central axis.
16. The method of claim 1, wherein the tank has a treatment fluid capacity of not more than four-hundred-fifty gallons.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The above and other aspects, features and advantages of illustrative embodiments of the invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein:
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(15) While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and may herein be described in detail. The drawings may not be to scale. It should be understood, however, that the embodiments described herein and shown in the drawings are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives to such embodiments that fall within the scope of the present invention as defined by the appended claims.
DETAILED DESCRIPTION
(16) An apparatus, system and method for treatment of an electric submersible pump (ESP) power cable will now be described. In the following exemplary description, numerous specific details are set forth in order to provide a more thorough understanding of embodiments of the invention. It will be apparent, however, to an artisan of ordinary skill that the present invention may be practiced without incorporating all aspects of the specific details described herein. In other instances, specific features, quantities, or measurements well known to those of ordinary skill in the art have not been described in detail so as not to obscure the invention. Readers should note that although examples of the invention are set forth herein, the claims, and the full scope of any equivalents, are what define the metes and bounds of the invention.
(17) As used in this specification and the appended claims, the singular forms a, an and the include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a support member includes one or more support members.
(18) Coupled refers to either a direct connection or an indirect connection (e.g., at least one intervening connection) between one or more objects or components. The phrase directly attached means a direct connection between objects or components.
(19) As used herein, the term outer or outward means the radial direction away from the center of a reel. In the art, outer diameter (OD) and outer circumference are sometimes used equivalently. As used herein, the outer diameter is used to describe what might otherwise be called the outer circumference or outer surface of a component such as tubular drum of a reel.
(20) As used herein, the term inner or inward means the radial direction towards the center of the reel. In the art, inner diameter (ID) and inner circumference are sometimes used equivalently. As used herein, the inner diameter is used to describe what might otherwise be called the inner circumference or inner surface of a component such as a tubular drum of a reel.
(21) As used herein, the term dip tank means a container holding a substance that is used for dipping or coating. An object may be immersed (or partially immersed) in a dip tank or it may be suspended over a vapor wafting from the tank.
(22) For ease of description and so as not to obscure the invention, illustrative embodiments are described in terms of an ESP power cable being treated with a rust remover or rust inhibitor. However, illustrative embodiments are not so limited and may be employed where it is desirable to coat any cable, wire, hose, spool, reel or flexible pipe with any fluid or powder substance. In one example, the treatment fluid may be washing fluid. In another example, the treatment fluid may be water and used as a grounding plane.
(23) Illustrative embodiments provide a system for treating an ESP power cable with a rust remover, rust inhibitor or both. Illustrative embodiments may provide an efficient method of coating an ESP power cable with rust treatment fluid, increasing the shelf life of used ESP power cables from the conventional untreated time frame of three to six months, instead to one year, three years or more. Illustrative embodiments allow improved handling of power cables that are heavy and long, such as up to about 9 tons in weight and up to about 12,000 feet in length, and at the same time require 15% or less by volume of the treatment fluid requiredreducing the conventionally required 2,500 gallons to instead about 330 gallons. Illustrative embodiments may eliminate the need for an overhead crane and decrease spillage and waste of treatment fluid as compared to full submersion treatment methods. Illustrative embodiments may also reduce or eliminate air pockets between the layers of cable that may otherwise prevent coating of those areas. Illustrative embodiments may provide flexibility of use for any type of treatment fluid and be modified to fit any size of steel cable reel, may be employed in close quarters and may minimize waste of treatment fluid.
(24) Illustrative embodiments provide a dip tank for an ESP power cable reel, which reel includes an ESP power cable wrapped on the reel. The reel may include about two to twenty layers of cable, depending on the length of the cable and the size of the reel. The dip tank may include a shallow basin containing rust treatment fluid such as a rust remover or rust inhibitor. The ESP power cable reel may be suspended horizontally on a shaft above the dip tank, and may be raised and lowered with respect to the basin. In illustrative embodiments, when lowered into the basin only the lower third portion of the ESP power cable reel may be immersed in the treatment fluid. In illustrative embodiments, the treatment fluid may cover just enough of the reel to allow fluid to reach the inner surface of the reel, and travel through an aperture in the reel barrel to reach the innermost layer of wrapped power cable. This positioning may allow both the ID and the OD of the power cable layers to be exposed to treatment fluid.
(25) When lowered into the basin, the ESP power cable reel may be rotated such that each portion of the reel is successively dipped into the treatment fluid as it reaches the bottom of the rotation cycle, and then removed from the treatment fluid as it turns towards the top of the rotation cycle. The ESP power cable reel may be rotated once (one 360 cycle), more than once, or for about one to four hours at about five rotations per minute (rpm), to permit the entire ESP power cable to be coated with treatment fluid. Rotation of the reel may also cause any air bubbles between the layers of cable to be displaced or moved such that the entire cable may be coated without any untreated pockets. Once the ESP power cable is sufficiently coated, the reel may be actuated upwards above the basin to dry, where the basin may catch any drippings. Treatment fluid may be pumped in and out of the basin with a fluid transfer pump and hoses attached to the dip tank. A bull gear drive, tire drive, chain and sprocket, belt and pulley, spray nozzle and/or other rotation mechanism known to those of skill in the art may cause rotation of the reel during treatment and/or apply treatment fluid to the power cable. A control panel may allow operation of the dip tank.
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(27) A reel of illustrative embodiments is shown in
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(35) Once reel 100 has been lowered into basin 115 and partially submerged in treatment fluid 165, ram 190 may be switched off and/or selector valve 310 may be switched to divert controlled flow coming from facility hydraulic power unit 230 to hydraulic gear motor 205, and then reel 100 may be rotated in a fashion similar to a rotisserie. Prior to rotation, cable phase ends 195 may be sealed to the lead jacket with clear fluorinated ethylene propylene (FEP) and/or polyimide splice tape. Cable phase ends 195 may be affixed to flange 120, such as with an eye bolt or U bolt, to secure cable phase ends during rotation of reel 100. In this fashion, cable phase ends 195 may be kept from coming loose during rotation, and sealed to prevent treatment fluid 165 from migrating up under the lead jacket of insulation.
(36) In some embodiments, reel 100 may be rotated 360 about its central axis. As shown in
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(38) In certain embodiments, a tire drive may be used to rotate reel 100 by friction. When a tire drive is used, care should be taken to ensure flanges 120 are not bent to improve effectiveness of tire drive 175 rotation.
(39) Tire drive 175 and/or bull gear drive 235 may be rotatable in both a clockwise and counter-clockwise direction, the rotation controlled by rotation switch 1030 (shown in
(40) As shown in
(41) As reel 100 with wrapped power cable 105 rotates, the bottom portion of reel 100 moves in and out of treatment fluid 165, such that each portion of ESP power cable 105 may be submerged in succession. When bottom portion of reel 100 is submerged, the portion of ESP power cable 105 at the bottom of reel 100 may be submerged at least at the outer most layer of ESP power cable 105. Drum inner surface 145 may also be submerged at the bottom portion of reel 100, allowing treatment fluid 165 to reach the innermost layer of ESP power cable near drum inner surface 145 through aperture 415. Additionally, treatment fluid may enter vents 425, further exposing middle layers of power cable 105 to treatment fluid 165. In this manner ESP power cable 105 layers may be exposed to treatment fluid 165 from both sides, and then seep inwards from both the inside (proximate drum inner surface 145) and the outside to treat inner and outer layers of ESP power cable 105. Reel 100 may rotate at about five revolutions per minute (rpm), and be permitted to rotate for about one to four hours, or another period of time depending on the type of treatment fluid 165 employed and/or the thickness of coating required. In one example, reel 100 may only be rotated once (one 360 cycle), for example to wet ESP power cable 105 with water. In another example, reel 100 may be rotated at 5 rpm for two hours to coat ESP power cable 105 with a rust inhibitor. In this time period, each portion of ESP cable 105 may be repeatedly exposed to treatment fluid 165 while reel 100 continuously rotates. Where treatment fluid 165 is rust inhibitor, the rust inhibitor may coat ESP power cable 105. The rotation of reel 100 may prevent any air bubbles from blocking a portion of ESP power cable 105 from receiving a coating. As reel 100 rotates, treatment fluid 165 may drip from reel 100. Basin 115, base 185 and/or spill tray 1100 may catch drippings from reel 100 and/or power cable 105. Drops that are caught may be reused.
(42) In addition to, or instead of, tire drive 175 and/or bull gear drive 235, another or alternative rotation means may be employed to rotate reel 100. In one example, a chain and sprocket or belt and pulley, which are well known to those of skill in the art, may be employed. Like bull gear drive 235, the belt and pulley or chain and sprocket may rotate reel 100 from spokes 140, hub 135 and/or the ends of shaft 130 rather than from the outer layer of ESP power cable 105 to prevent slipping. A spray nozzle 240 (shown in
(43) Once ESP power cable 105 is sufficiently coated with rust inhibitor, rust remover or other treatment fluid 165, support members 125 may be actuated and/or extended to a raised position, as shown in
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(45) An apparatus, system and method for treating ESP power cables has been described. Illustrative embodiments provide a system and method for removing rust from an ESP power cable and/or coating an ESP power cable with rust inhibitor. Illustrative embodiments may treat 100% of an ESP power cable with minimal waste of treatment fluid, and requiring less volume (such as 85-87% less) of treatment fluid than conventional methods. Further, the same system may be used for both rust removal and rust inhibitor application. Illustrative embodiments may require only a small amount of space since only a single reel is needed and no deep pits are required, and may eliminate the need for an overhead crane. Illustrative embodiments may prevent air bubbles between layers of ESP power cable from blocking coverage of treatment fluid coating. Illustrative embodiments may provide improved handling of long, heavy ESP power cables. The treatment of ESP power cables with rust inhibitor using illustrative embodiments may prolong the shelf-life of ESP power cables and permit those cables to be reused multiple times, saving on cost and waste.
(46) An apparatus, system and method for treatment of an ESP power cable has been described. Further modifications and alternative embodiments of various aspects of the invention may be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the scope and range of equivalents as described in the following claims. In addition, it is to be understood that features described herein independently may, in certain embodiments, be combined.