DOWNHOLE TOOL WITH PROTECTIVE COVERING

Abstract

Degradable and abradable protective covers closely fitted about degradable downhole tools, and methods and devices for making, packaging, transporting and using degradable downhole tools with such covers.

Claims

1. An assembly for use in a cased hydrocarbon well having downhole fluid, comprising: a settable downhole tool, the tool having a mandrel, slip or slips and cone or cones; a protective wrap located about at least a portion of the tool, the protective wrap comprised of shrinkable material, tightly covering an outer surface of at least the slip or slips and cone or cones, and is hydrolytically degradable in the downhole fluid, the tool covered by the protective wrap comprising a covered tool; and the covered tool is adapted to be run into the well's casing, is adapted so the protective wrap will then at least partially degrade in the well's downhole fluid and cease covering the tool, and is adapted so the tool can then be set directly into the casing and the sealed directly against the casing.

2. The assembly of claim 1, wherein at least one of the mandrel, slip or slips, and cone or cones is degradable in the downhole fluid and the tool is configured and comprised so after the tool is set in the well's downhole fluid against the casing and used in completion operations in the well, then degradation of at least the mandrel, slip or slips and cone or cones will cause the tool to release from the casing.

3. The assembly of claim 1, wherein the protective wrap is longitudinally long enough to at least cover the tool's slip or slips and cone or cones, the protective wrap is attached to at least some larger radial outer surfaces of the slip or slips and cone or cones and is not attached to some smaller radial outer surfaces of the slip or slips and cone or cones, and the protective wrap provides a covered tool outer surface which is smoother than a similar tool without the wrap, and wherein the covered tool is capable of sliding through a horizontal leg of the well having debris on the bottom of the horizontal leg with less horizontal force than a similar tool without the wrap; and wherein the wrap's covering is at least 2.0 mil thick for providing resistance against sand abrasion as the covered tool is run in through the horizontal leg.

4. The assembly of claim 1, wherein the protective wrap is not laminated to the tool, is not an integral layer of any part of the tool and is between 0.5 to 7 mil thick.

5. The assembly of claim 1, wherein the protective wrap is not an integral layer of any part of the tool and is between 1.5 to 5 mil thick.

6. The assembly of claim 1, wherein the protective wrap is not an integral layer of any part of the tool and is the wrap is between 2 to 3.5 mil thick.

7. The assembly of claim 1, wherein the protective wrap is comprised of a cylindrical shrinkable film joined together at a joint to form a cylinder, the film covering at least the tool's one or more slips and one or more cones, and the film's joint is continuous and parallel to the mandrel's axis.

8. The assembly of claim 1, wherein the protective wrap is comprised of a continuous shrinkable tube covering at least the tool's one or more slips and one or more cones.

9. The assembly of claim 1, wherein the protective wrap is comprised of a continuous shrinkable preformed bag covering at least the slip or slips and cone or cones and an end of the tool.

10. The assembly of claim 1, wherein the downhole tool is further comprised of a lower retaining element having set screws on the tool's lower end and/or a higher retaining element having set screws on the tool's higher end, and the protective wrap covers at least the slip or slips and cone or cones, and does not the cover set screws in the tool's lowest and/or highest retaining elements.

11. The assembly of claim 1, wherein the protective wrap is primarily unidirectionally shrinkable and arranged about the tool so protective wrap shrinkage primarily reduces the wrap's radius about the tool and does not primarily reduce the wrap's length along the tool, the slip or slips have inserts or withers, and protective wrap shrinkage about the tool does not cause the slip or slips inserts or withers to penetrate or tear the protective wrap.

12. The assembly of claim 1, wherein the protective wrap has visually apparent indicia, namely, at least one of a color, a stripe, a design or a symbol, which visually differentiate between different types of wraps, namely, wraps having different thicknesses or compositions or which visually differentiate between different types of tools, namely, tools having different functions or measurements.

13. The assembly of claim 1, wherein the protective wrap is optically clear.

14. The assembly of claim 1, wherein the protective wrap is comprised of one of the following: fluorinated ethylene propylene (FEP), polyolefin, PVC tubes, polyvinylidene fluoride (PVDF), silicone rubber, PLA, PGA, PVOH, PTFE (fluoropolymer) or Viton.

15. The assembly of claim 1, further comprising a moisture impermeable outer shell, the shell entirely enclosing the covered tool, and adapted to be easily removable from the covered tool prior to inserting the covered tool into the casing.

16. The assembly of claim 1, further comprising a label on the inside or the outside of the protective wrap, the label being degradable in the downhole fluid.

17. The assembly of claim 1, wherein the protective wrap provides the tool with protection against sand infiltration and sand friction so the tool within the protective wrap suffers less sand infiltration and less sand friction than a similar tool without the protective wrap.

18. An assembly for use in a cased hydrocarbon well having a downhole fluid, the assembly comprising: a settable downhole tool, the tool having a mandrel, slip or slips and cone or cones, wherein at least one of the mandrel, the slip or slips and cone or cones is degradable in the well's downhole fluid, and the tool is configured and comprised so the degradation of one of the mandrel, the slip or slips and cone or cones when the tool is set in the casing will release the tool from the casing; a protective wrap which is degradable in the downhole fluid and which covers an outer surface of at least the slip or slips and cone or cones; the covered tool is adapted to be run into the well's casing, and then the wrap to at least partially degrade in the well's downhole fluid, and then the tool to be set into and sealed against the casing; wherein the wrap is primarily unidirectionally shrinkable and arranged about the tool so shrinkage of the wrap primarily reduces the wrap's radius about the tool and does not primarily reduce the wrap's length along the tool; wherein the wrap is comprised of one of the following: fluorinated ethylene propylene (FEP), polyolefin, PVC tubes, polyvinylidene fluoride (PVDF), silicone rubber, PLA, PGA, PVOH, PTFE (fluoropolymer) or Viton; wherein the wrap covers at least the slip or slips and cone or cones, does not cover a portion of an outer radial surface of a first end of the tool, and does not cover a portion of an outer radial surface of a second end of the tool; wherein the wrap is adapted to make the covered tool smooth enough to enable the covered tool to slide through a horizontal leg of the well having debris in the horizontal leg with less force than a similar tool without the wrap, namely, the wrap is longitudinally long enough to cover the tool's slip or slips and cone or cones, and the wrap provides a covered tool outer surface which is smoother than a similar tool without the wrap; wherein the wrap's covering is at least 2.0 mil thick for providing resistance against abrasion as the covered tool is run through a horizontal leg; and, a moisture impermeable outer shell, the shell entirely enclosing the covered tool, and adapted to be easily removable from the covered tool prior to inserting the covered tool into the casing.

19. An assembly for use in a cased hydrocarbon well having aqueous downhole fluid, comprising: a settable downhole tool, the tool having a mandrel, slip or slips and cone or cones and elastomeric seal; a protective wrap which is degradable in the well's downhole fluid and which covers an outer surface of at least the slip or slips and cone or cones and elastomeric seal, the tool covered by the protective wrap comprising a covered tool; and wherein the covered tool is adapted to be run into the well's casing, is adapted so the protective wrap will then at least partially degrade in the well's downhole fluid and cease covering the tool, and is adapted so the tool can then be set directly into the casing and be sealed directly against the casing; and wherein at least one of the mandrel, slip or slips and cone or cones is degradable in downhole fluid and the tool is configured and comprised so after the tool is set in the well's downhole fluid against the casing and used in completion operations in the well, then degradation of at least the mandrel, slip or slips and cone or cones will cause the tool to release from the casing; and further comprising: a moisture impermeable outer shell, the shell entirely enclosing the covered tool, and adapted to be easily removable from the covered tool prior to inserting the covered tool into the casing.

20. The assembly of claim 17; wherein the protective wrap is comprised of a polymer acid and is hydrolytically degradable in an acidic aqueous downhole fluid; wherein the protective wrap is longitudinally long enough to at least cover the tool's slip or slips and cone or cones, the protective wrap is attached to at least some larger radial outer surfaces of the slip or slips and cone or cones and is not attached to some smaller radial outer surfaces of the slip or slips and cone or cones, and the protective wrap provides a covered tool outer surface which is smoother than a similar tool without the wrap, and wherein the covered tool is capable of sliding through a horizontal leg of the well having debris on the bottom of the horizontal leg with less horizontal force than a similar tool without the wrap; and wherein the wrap's covering is at least 2.0 mil thick for providing resistance against sand abrasion as the covered tool is run in through the horizontal leg.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1 is a drawing of a downhole tool within a pre-shrunk covering. FIG. 1 A shows the covering shrunk tight. FIG. 1B shows the covering shrunk smooth.

[0027] FIGS. 2A, 2B and 2C illustrate three forms of a protective cover: tubing or sleeve, film or sheet, and tape.

[0028] FIGS. 3A, 3B and 3C are side views of assemblies in pre-heated (FIG. 3A), being listed (FIG. 3B1, and shrunk (FIG. 3C) conditions. FIG. 3D illustrates the tool and wrap assembly inside an outer, mature impermeable bag, which outer bag will be removed before the tool and inner cover are inserted to.

[0029] FIGS. 4A and 4B illustrate methods of making a disclosed tool and wrap assembly.

[0030] FIG. 5 is a view of a manner in which heat is applied to the assembly in a method of making applicant's assembly.

[0031] FIG. 6A illustrates a non-heat shrink rigid plastic tube with an end cap or caps for snug receipt of the assembled downhole tool.

[0032] FIG. 6B illustrates a clear cling wrap for use in wrapping a downhole tool.

[0033] FIG. 7 illustrates a method of applying heat shrink wrap to a downhole tool.

[0034] FIG. 8 is an elevated view of a downhole tool illustrating its cylindrical nature and showing an area of an outer surface of the tool that may be covered with applicant's wrap.

[0035] FIG. 9 is a perspective view of a transport container for transporting a multiplicity of downhole tools.

[0036] FIG. 10 is an elevated view of a rack for use with the transport container.

[0037] FIG. 11 is a top view of a rack for use with the transport container.

[0038] FIG. 12 is a side view of the container showing cushion 65.

[0039] FIG. 13 illustrates a method of paperless tracking and slipping of Applicant's tool and wrap assembly.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0040] FIG. 1 illustrates downhole tool 12 having an outer surface 22, including sidewall 12a, bottom wall 12b and top wall 12c (see FIG. 3C) at least partially covered by an unshrunk wrap 14. FIG. 1 illustrates a preshrunk wrap about the tool. FIG. 1A illustrates a wrap shrunk tight about the tool so the wrap follows the contours of the outer surface of the tool. FIG. 1B illustrates the wrap in a smooth shrunk condition, achieved by using less heat than used to achieve the shrink tight configuration of FIG. 1A and useful in some embodiments as further described herein.

[0041] FIGS. 2A, 2B and 2C illustrate three forms of heat shrinkable material that may be used to form a wrap 14. FIG. 2A illustrates a heat shrink material comprising a sleeve or tube 16 (open at both ends), typically cylindrical, and, in some embodiments, somewhat stiff, and having a diameter selected to receive the tool therein. In FIG. 2A, the tube has indicia 17 on its surface, the indicia including, for example, a trademark and/or instructions for use. Indicia 17 may be present on any of the forms of the wrap disclosed herein. Indicia may be printed on the covering or applied on an adhesive backed label which is placed on the wrap or an internal part of the covering, including color, strips, dots and other designs. FIG. 2B illustrates a heat shrink sheet or film 18 that is a thin, flexible sheet with almost no rigidity and no freestanding structure. It may be wrapped around the outer surface of the downhole tool prior to shrinking it with the application of heat. FIG. 2C illustrates a heat shrink adhesive tape 20 that may comprise a heat shrinkable substrate 20a with an adhesive layer 20b on one surface thereof, which tape may be used alone or in conjunction with sleeve 16 and/or film 18 to provide wrap 14 to downhole tool 12.

[0042] FIG. 3A illustrates downhole tool 12 which may include a free or captured ball 12a and a mandrel 12b, with multiple elements 12c entrained on the mandrel in ways known in the art. Elements may include elastomers, cones, slips, rings, setting elements in the like. In some embodiments, downhole tool 12 is a settable downhole tool configured to isolate a zone in a wellbore, for example for completion or refracing operations. FIG. 3A illustrates a preshrunk (before heat is applied) configuration with wrap 14 in a preshrunk configured in, on, or about at least part of the outer surface of the downhole tool. Enclosing the ball intended for the tool's ball seat within the covering eliminates the potential for workers at the well site to use a ball which is not exactly matched to the tool's ball seat.

[0043] FIG. 3B illustrates the application of heat to wrap 14 so it constricts or reduces its preshrunk diameter about the tool so it snugly contacts the outer surface, typically at least part of the tool's outer diameter, preferably at least the elastomer, cone or cones and slip or slips when in a cooled or shrunk configuration following being shrunk about the tool. Heat may be applied artificially or, in some embodiments, the wrap may naturally shrink at warm temperatures. FIG. 3C illustrates a post-shrunk tool and wrap assembly 10 ready to go downhole. In this configuration, only part of the tool is covered, leaving some of the ends exposed, here, about 2-3 on each end is left exposed (for example, to allow the operator to access set screws). Note in FIG. 3C that, in some embodiments, a series of perforations 15 may be made in wrap 14, before or after covering tool, to help removal of wrap before sending tool downhole or to help reduce the backpressure on the tool during setting. FIG. 8 illustrates a preferred embodiment, wherein the wrap may cover at least the tool's slips, cones and elastomer when in a shrunk condition, and leave the tool's ends exposed. The wrap covers, in some embodiments, at least sharp withers or inserts of the slip, and does not cover set screws in the tool's lowest and highest retaining rings.

[0044] FIG. 3D illustrates that tool and wrap assembly 10 may be placed inside an air and moisture impermeable outer bag or outer shell 44 to prevent moisture from contacting the tool and wrap assembly and protect it from UV light. The outer bag or outer shell 44 will typically be removed by the operator at the well site prior to sending the tool and wrap assembly downhole. In an embodiment, the bag is a 10 to 26 metallized bag available from Western Industries, Carrollton, Tex. In some embodiments, outer bag or outer shell 44 is biodegradable. A desiccant 46 may be placed within the sealed outer bag or outer shell 44 to help control humidity inside the outer bag and protect the tool and wrap assembly from moisture.

[0045] FIG. 4A illustrates tube 16 in a preshrunk configuration with downhole tool 12 therein. There is typically a small gap 24 between the outer diameter of the tool and the inner diameter of the sleeve which gap may be about to 1 inches. FIG. 4B illustrates a film or sheet 18 wrapped around tool 12 in a loose fashion with the sheet's ends joined at seam 28 which may be covered or secured with tape 20. Sheet 18 typically comes in a roll. A length of the material may be used to wrap the tool in one or more plies with the seam 28 providing joinder in the preshrunk condition. In another embodiment, (not shown) tape is wrapped around the exterior of some or all of the exterior of the downhole tool. Heat is then applied to the assembly causing the material to contract, especially radially, until it contacts the outer surface of the tool. End sheets 26 may be applied, with tape or the like to seal the ends of the cylindrical tool and provide a complete, rather than partial cover to the outer surface of the tool. Some embodiments may use a bioplastic resin as a protective cover. Bioplastic materials are derived from bio-logical substances rather than from petroleum. Bioplastics may include composible bioplastics. Polylactic acid is a heat shrinkable biodegradable bioplastic derived from plants, such as corn. In some embodiments, if may heat shrink to 70% TD in 10 sec. at 80-100 C. with no smile effects.

[0046] FIG. 5 illustrates multiple tool and wrap assemblies (preheated) 10 and on a cart 30, ready for placement in an oven 32. Heat from the oven may then be applied to multiple assemblies 10 for the cover shrinkage operation. Oven 32 may provide heat via convection, conduction or radiation, or combination of the three.

[0047] In their pre-shrunk configuration, shrink wrap sleeves 16 may be open at both ends, and configured to receive the downhole tool therein. The sleeve may be a bag open at one end and closed at the other end. The coverings may be clear and/or include multiple colors, graphics, indicia, and branding. The coverings offer tool tamper protection and evidence of tool tampering, especially when a full body shrink sleeve is used. Some heat shrink products include a vapor corrosion inhibitor (VCI). In some embodiments, the covering is breathable. A sleeve (tube) open at both ends may be subsequently closed at one or both ends following insertion of the tool into the sleeve. A non-rigid sleeve closed at one end (bag) may be closed or party closed at the other following insertion of the assembled tool.

[0048] In one embodiment, custom printed shrink sleeves made of degradable polyglycolic or polylactic acid are provided. The sleeves are slid over the downhole tool and, in some embodiments; hot air is applied, in some embodiments, with a hoop shaped heating apparatus or any other suitable device. This causes the wrap to shrink and conform to the plug in a uniform manner. The sleeve, bag or sheet may be printed with a company logo, running instructions, etc. The rate of dissolution of wrap 14 can be selected in part by the number of sleeves used (multiple plies on a single assembled tool), the thickness of an individual sleeve (thicker slows degradation), selection of sleeve materials, or other adjustments to the sleeve.

[0049] In one embodiment, sheet 18 is Biolefin 2.0, a biodegradable shrink film about 0.6 mil thick, which may be perforated or not. It is a food grade, acid-free, oxo-biodegradable shrink film. It shrinks clear and is available in 14 to 18 widths. See www.nationalshrinkwrap.com. Multiple lies (wraps) may be used on one tool.

[0050] Another heat shrink sleeve, open at both ends, suitable to wrap downhole tools, in some cases downhole tools with some or all of their elements being degradable in a downhole fluid, is Earth First PLA. This heat shrink sleeve may be provided and be useful within a range of about 1.2 mil to 6.8 mil, and in some embodiments about 2.8 mil. This heat shrink sleeve is compostable according to ASTM D6400. It is made from non-petroleum material such as renewable resources, for example, cane sugar, tapioca roots and corn. Unlike some other shrink films, this product can be stored at up to 100 F. without instability. It is a polylactic acid film. These films may be shrunk in many types of commercially available heat shrink tunnels including: infrared, hot air, steam flow or any combination thereof. They provide full body or partial body shrinkage in unidirectional or bidirectional. In some embodiments, its ultimate tensile strength is 48 MPA (machine direction) and 130 MPA (transverse direction), ASTM D882. Westrock provides shrink sleeve packaging for partial or full coverage, including PLA sleeves that are biodegradable and compostable.

[0051] Regardless of the heat shrink wrap used, in some embodiments, heat shrink containers or wraps may be between and 2 inches greater diameter in their preshrunk configuration than the tool's diameter. More preferably, the preshrunk heat shrink containers or wraps may be between inch and 1 inches greater in diameter than the tool's diameter. Most preferably, the preshrunk heat shrink containers or wraps may be between three quarters of an inch and 1 inch greater in diameter than the tool's diameter. For example, to contain or wrap a 4 inch diameter downhole tool, a container or wrap that is about 5 to 6 inches in diameter may be used, or containers or wraps otherwise sized as described may be used.

[0052] Polyvinyl chloride (PVC) may be used for low cost sleeves. It provides a gloss finish and up to 65% shrinkage. Polyethylene terephthalate films may also be used and can shrink up to 75% of their original size and may encompass even the most intricate shapes. It has good product resistance and high clarity. OPS film is a high clarity, petroleum based shrink film, which shrinks up to 70% of its original size. Polylactic acid (PLA) film is a high clarity, bio-based film made from corn. It may shrink up to 75% of its original size and is 100% compostable, conforming to ASTM 6400. It may be used in conjunction with PLA labels. Some films can combine the use of the PLA biopolymer with OPS and/or PETG. These hybrid films can be designed for varying degrees of degradability in a downhole fluid. In some embodiments, the polylactic acid film will heat shrink between about 157-276 gauge (ASTM D 4321) and may, in some embodiments, have an ultimate tensile strength between 7000 psi-19,000 psi (ASTM D 882) shrinkage may be 5 and 75% at 85 C. (unrestrained 10 seconds circulating water bath).

[0053] Heat shrink wrap choices may be made based on the percentage of shrink needed, desired finish (gloss/matte), user requirements, degradation considerations, and sustainability. Shrink percentages may range from 5 to 90% of original size. A cylindrical downhole tool, may be 2 to 14 inches in diameter and 16 to 46 inches in length.

[0054] In some embodiments, the downhole tool is a conventional plug such as a zonal isolation tool, bridge plug, packer or the like. The disclosed plastic tube, film, wrap or sleeve is placed about the tool and is sealed about the tool. This may include shrinking the wrap about the tool, or tightly wrapping of the wrap about the tool. Tool instructions, tool identification, RFID Chip tracking label, seller identification and the like may be included on a label located between the tool and the wrap and visually readable through the wrap. The information on the protective cover may include a scannable code, QR or bar code and may allow the tool manufacturer to go paperlessnot needing to include paper instructions. Information may include instructions, tool data, and serial number. Such a label or information may be placed or printed on the outside or inside of the wrap. Such a wrap protects the tool from moisture, corrosion and abuse prior to the tool being attached to the drill string and run down hole. If the tool is degradable by moisture, such as a tool having elements made of degradable PGA, PLA, magnesium, aluminum (or their alloys) or other degradable materials, the wrap protects the tool from premature corrosion or degradation due to atmospheric humidity. A degradable setting tool has one or more structural elements which, when they degrade, cause the tool to release from the casing. Typical structural elements are the mandrel, slips or cone.

[0055] In some embodiments, the shrink wrap protects handlers and workers from the tool's sharp edges, such as the wickers or inserts of slips or tool threads. In FIG. 8, a downhole tool is a settable downhole tool and includes elastomer 12d and slips 12e. Coverage zone Cz of shrunk sleeve or wrap preferably covers the elastomer, cones and slips (or at least one slip). Such a wrap holds elements of the tool together, such as holding the particular ball appropriate for the tool's ball seat to the tool's ball seat. In closing the ball intended for the tool's ball seat within the covering eliminates the potential for workers at the well site to use a ball which is not exactly matched of the tool's ball seat. Such a wrap protects the tool and delays degradation of the tool as it travels downhole, through downhole fluid, through abrasive casing and abrasive debris in downhole fluid to the location in the borehole it is to be set or used. Such a wrap may be strong enough to sufficiently resist tearing and degradation so the wrap may serve these functions, and may also be sufficiently weak and breakable so when the tool is set in the casing or otherwise used in the casing, the use of the tool is not impeded by the wrap. The wrap may be comprised of degradable materials so within a predetermined period of time after it enters the downhole fluid it does not interfere with completion or production. A desiccant 46 (see FIG. 3D) can be included within the wrapped tool or between the tool and wrap assembly 10 or between the tool and the wrap to further protect the tool from moisture or humidity prior to use of the tool downhole. If the tool is one which a business does not wish competitive businesses to see, the wrap may be opaque to protect the tool from inspection.

[0056] In some embodiments, the wrap is not a heat shrink wrap. A printable and degradable wrap is EcoSol a water soluble packaging solution from Cortex Corporation. EcoSol is a polyvinyl alcohol (PVOH) wrap which after a few minutes submerged in water at an elevated temperature leaves a harmless, non-toxic, aqueous solution of polyvinyl alcohol. The mechanical properties of EcoSol packaging conform to ASTM D 882-02 for breaking factor, tensile strength of break, elongation and strength. Its tear strength is tested according to ASTM D 1922-06a and dart drop impact resistant for ASTM D 1709-04. EcoSol is not heat shrinkable. It may be wrapped tightly around the tool or formed into a bag which will snugly receive the tool. While some of the foregoing embodiments discuss heat shrinkable materials, some of which are degradable, in some other embodiments, the covering may be a water soluble, biodegradable film, wrap or package, such as one made of polyvinyl alcohol (PVOH) which is chemically resistant to mineral, vegetable, and animal oils as well as certain hydrocarbons. PODS (degradable detergent capsules) are sometimes comprised of PVOH. They will degrade in an aqueous solution and may or may not be heat shrinkable. The time required for dissolution varies depending upon the thickness of the film and the temperature of the water. In one embodiment, an EcoSol 1.5 mil thick at 68 F. begins to dissolve within thirty seconds and is fully dissolved in five minutes of contact with an aqueous solution at 72. Thicker film takes longer to dissolve. In some embodiments, the shrinkable or non-shrinkable film is selected to dissolve between 2 to 240 minutes after immersion in an aqueous solution temperature greater than 20 C. or up to 150 C.

[0057] Like heat shrinkable wrap, a biodegradable non-heat shrinkable film is not a coating on the tool per se, but is a bag, sack or wrap for enclosing an assembled tool. However, when sealed, or partially sealed, and snug to the surface of the tool, it provides a delay in degradation of the tool, and also provides protection while the tool is being handled, prior to and after insertion in the well hole casing

[0058] Another product, heat shrinkable, is Cortex MilCorr VpCI shrink film. It provides UV protection for outdoor storage and protects from corrosion multiple metals including steel, aluminum, brass, copper, iron and the like. It may be used to prevent rust on iron and steel parts of the tool. It will protect against salt air and humid environments, moisture, aggressive industrial atmosphere (it includes a phase corrosion inhibitor) and dissimilar metal corrosion. The corrosion inhibitor is vaporized and condensed on all metal surfaces within the enclosed space and diffused to every area of the enclosed tool, protecting the exterior as well as void spaces in recessed areas.

[0059] Another non-heat shrinkable plastic sheet embodiment is use of a stretchable cling wrap 40 to at least partially cover the assembled tool, which cling wrap may be clear and degradable. Cling wrap is typically used for sealing food items in containers. Cling wrap can be used in a variety of thicknesses including 0.5 mil. Little stretch is needed to wrap it around the typically cylindrical tool several times. It clings to the tool's edges and remains tight over the tool, even without adhesive. One biodegradable cling wrap is known as BioBag. In FIG. 6B, three plies 40 a/b/c are wrapped tightly, while under tension (slight stretch) around the outer surface of assembled downhole tool 12. Seam 40d is self-sealing and holds to the previous ply. Cling wrap 40 may be clear and cover a label 17, which may be degradable.

[0060] In some embodiments, a wrap, bag, sleeve or sheet may be starch-based films in bags (typically called a BioBag) made of starch of fiber typically corn, soy or potatoes. Oxo-degradable bags are different from BioBags. They are additive-based biodegradable film/bags which include additives to the resin to control degradation upon exposure to different conditions. Oxo-degradable films degrade by oxidation, hastened by chemical additives. Shrink wrap may be Oxo-degradable.

[0061] Other types of degradable plastics may be used, such as additive-based wraps, including hydro-biodegradable plastics which degrade by hydrolysis and thermal-based biodegradable plastic which degrades with exposure to heat. Degradation rates for these wraps or bags may be controlled if the environment, such as downhole fluid, is generally known, for example, heat conditions and chemical nature of the fluid (for example, brine).

[0062] In another embodiment, a coating is directly applied to the tool, either to the assembled tool or to one or more of the tool's parts prior to assembly. For example, a degradable polymer portion of a downhole tool may be comprised to begin degrading immediately upon contact with the well's downhole fluid. For some well sites and some operations, degradation of the degradable tool immediately upon it entering the wellbore may be desirable. For other well sites and other operations, however, such degradation beginning immediately may be undesirable. In the latter circumstance, either the assembled tool or parts of the tool prior to assembly have a coating applied which coating separates the degradable polymer parts of the tool from the degrading downhole fluid. Application of the coating may be by spraying the tool or parts, brushing the coating on the tool or parts or otherwise. For some applications, multiple layers of coatings may be applied to the tool or parts.

[0063] For example, if a particular tool part is comprised of a degradable polymer, such as a degradable PLA or PGA, which will begin hydrolytic degradation immediately upon being immersed in the aqueous downhole fluid, then a water impermeable coating on that part will delay the onset of that part's degradation. A part or tool with a water impermeable coating will initially separate the water degradable part from the aqueous downhole fluid when the downhole tool enters the downhole fluid. However, as the tool is lowered into the wellbore it will rub and bump against the casing, the rubbing and bumping scratching through the coating. The scratched areas of the tool will then be in direct contact with the aqueous downhole fluid. The parts of the tool opened to contact with the downhole fluid by the scratches will then begin to degrade.

[0064] This use of a water impermeable coating to delay the initiation of water degradable parts in the downhole tool, and then use of casing/downhole tool scratches through the coating to initiate degradation provides an additional element of control to the tool's degradation. A degradable tool which, without the coating would degrade too quickly, becoming too soft too quickly for reliable use in fracing operations, by use of a described coating, can have its degradation delayed so the tool is more useful in the particular target fracing operation. Thereafter, the tool degrades, degradation beginning at the places where the coating has been scratched or otherwise abraded off of the tool.

[0065] This ability to delay onset of degradation of the tool permits use of degradable materials in the tool which are more rapidly degradable than would be possible without use of the coating. Use of a described coating protecting a degradable tool permits use of degradable tool materials that will more quickly degrade and will more quickly open the wellbore after the tool's intended use in the fracing operation. In some embodiments, such a tool may produce an unobstructed borehole more quickly than a similar tool without such a coating and which is comprised of a degradable material which degrades more slowly due to the need for the similar tool to not soften too much prior to the fracing operation

[0066] Not all possible impermeable coatings are as useful for the described purpose as others. For example, many paints or coatings will not sufficiently adhere to a tool made of degradable polymer such as PGA and PLA. Normal wear and tear during transportation, handling, making up the drill pipe etc. may prematurely remove such coatings. In addition to sufficient adherence to the tool being a requirement, in some embodiments, the coating must be hard enough and thick enough to not so completely abrade off of the tool during initial insertion into the borehole that too much downhole fluid/degradable tool contact occurs immediately upon the tool entering the borehole. On the other hand, the coating must be sufficiently frangible and abradable that it will incur sufficient through coating scratches, cuts and abrasions and permit sufficient downhole fluid/degradable tool contact as the tool approaches its targeted area in the cased borehole or is used for the tool's intended functions. For example, it has been found that Krylon primer paint adheres to degradable polymers sufficiently to decrease degradation of the degradable tool in the downhole fluid, but also scratches and abrades sufficiently as it approaches its target fracing operation downhole for it to be a useful coating for the described purposes. Other hard tough coatings, such as ceramics coatings, are useful for this purpose.

[0067] As described above, some parts of a degradable tool may be more degradable than other parts. Some parts of a downhole tool have different structural requirements. Accordingly, some parts of a degradable downhole tool may have a cover or coating applied, while other parts of the tool may not. In other embodiments, different parts may have a different cover or coating. In other embodiments, different parts may have coatings with different thicknesses. Parts that are coated, choice of coatings, thickness of coatings and the like may be adjusted to provide a degradable tool which retains sufficient structural strength at downhole operation point to complete its intended operation, and for the tool to then quickly degrade, release from the casing, and thereafter substantially completely degrade.

[0068] FIG. 6A illustrates a rigid, hard plastic tube or sleeve 42 into which an assembled tool 12 may be pressed, in one embodiment such that outer elements of the tool scrape the inner walls of sleeve 42 during insertion, a cap or caps 42a (may be refused, glued or threaded) may then engage one or both ends of the sleeve.

[0069] FIG. 7 illustrates a method for shrinking the wrap onto the wrapped plug using heat. This method uses a two-stage convection hot air tunnel. The illustrated oven is a two-stage convection hot air oven from PDC International Model RAD/KRC 24-72-54 Dual Zone Hot Air Tunnel.

[0070] FIGS. 9-12 illustrate a transport container 54 for transporting a multitude of cylindrical elongated downhole tools, which may or may not be wrapped according to the specifications above. Transport container 50 typically comprises a rectangular housing 52 with a pivoting lid 56 attached using a multiplicity of hinges 58. Lid 56 or upper rim or perimeter of housing 52 may include weather-stripping 67, so lid 56 is ultimately secured to the upper rim or perimeter of housing 52 in a watertight manner. Body 54 of housing 52 may be made of the HDPE sheet (black) which may be rounded at the corners. A RFID tag or QR code or GPS tracker 53 (or one or some of these) may be secured to the outer surface or any other suitable place on the container so that it may be scanned before, during or after shipment for identification and other purposes. A GPS tracker 53 may be included on or attached to housing 52 or any other suitable location for instantaneous location of the container.

[0071] As can be seen in FIG. 9, a rack 60 may include a top plate 62 and a bottom plate 64 held and spaced apart relation by locators 66. Locators 66 may comprise an inner threaded rod 70 on which a PVC sleeve 68 is entrained. The PVC sleeve is dimensioned to contact the underside of the upper plate and the top side of the lower plate to define a lateral spaced apart arrangement between the two plates. The threaded rod may have a nut and washer on the bottom and a wing nut on the top to tightly secure the top and bottom plates against the top/bottom of the PVC sleeve to ensure suitable spaced relation. The plates may be spaced apart a distance less than the length of the tool which is to be slotted into the holes for shipment. Multiple holes 72 (see FIGS. 9 and 11) on both top and bottom plates have a matching pattern and aligned so a top hole sits directly above a bottom hole. Holes 72 are dimensioned to be slightly larger in their inner diameters than the outer diameters of the downhole tools. Thus, a downhole tool may be slotted vertically into the paired holes and remain spaced apart from adjacent tools likewise slotted in other sets of holes for shipment. Rack 60 is dimensioned to be snuggly received or fastened within the inner sidewalls of body 50 so it does not move laterally. Gravity will hold the emplaced downhole tools in their sets of holes within body 54 of housing 52. Container 54 may at the top. The rack and container are arranged so when a tool is in place in the rack, its top is above the top plate for easy removal of the tool. Cushion 65 may cushion the lower end of the slotted tools, dampen tool vibration and maintain the tools above the floor of the body. The inside cover of the lid may also have a cushion layer.

[0072] FIG. 13 illustrates the use of a bar code, QR code or other machine readable label or sticker that may be applied to either the transport container and/or the tool and wrap combination 10, including either the protective cover or the outer wrap or cover. The bar code or QR system is popular in the automotive industry. Its applications may be used the oil and gas industry to provide a paperless system of product tracking, item identification, time tracking, invoicing, document management, document instructions, and general marketing. With smart phones or other handheld reading devices usable, all steps between the initial tool packaging and up to run in downhole may be documented without paper and which carries the scannable code on a biodegradable substrate. Typically, a QR code would be unique to a tool serial number and/or part number and/or part description, provided by the manufacturer and which may be password-protected and may include instructions of use. Data added digitally may include individual shipping instructions and destination, invoicing instructions and comments. This provides total paperless tracking as the QR code on the wrapper, which wrapper is itself, is in some embodiments, biodegradable and the container in which the tools are shipped, is in some embodiments, both reusable and biodegradable. This paperless biodegradable system anticipates adding information along the way and for communication among and between the manufacturer, the end user and the middleman, such as a distributor.

[0073] The shipping system for the tools may include: transport container and protective wrap, and/or outer bag for the tool or tool and wrap combination. All of the foregoing may be green in that all of these may be comprised of biodegradable materials. Moreover, it has been seen that the shipping system may be paperless, thereby further reducing the carbon footprint.

[0074] This application discloses and assembly for use in a cased hydrocarbon well, the assembly comprising: a settable downhole tool having multiple elements entrained upon a mandrel thereof, the downhole tool having an outer surface, the tool in the preset configuration; and, a degradable protective wrap at least partly covering the outer surface of the tool in a snug fashion. In some embodiments the wrap is heat shrink wrap, the protective cover further includes indicia on an outer surface thereof, at least some of the multiple elements of the downhole tool are degradable in a downhole fluid, the protective wrap is compostable, a label is included between the protective wrap and the outer surface of the tool, at least part of the protective wrap is clear, a label on an outer surface of the protective wrap, the label is biodegradable, the protective wrap is comprised of a polymer acid film, the polymer acid film is comprised of polyglycolic acid or polylactic acid, the polymer acid film is degradable, a sealed outer wrap adapted to sealingly enclose the settable downhole tool with the protect wrap thereon.

[0075] This application discloses method of making a tool and wrap assembly, the method comprising: providing a downhole tool; placing a protective wrap about the tool, the wrap being a shrinkable plastic wrap comprised and configured to when shrunk around the tool; shrinking the wrap material about the tool; the shrunk wrap encasing the tool and comprised so the wrap helps protect the tool from atmospheric humidity, and the wrap does not interfere with the tool's use downhole; wherein the protective wrap is degradable in a downhole fluid.

[0076] This application discloses a tool and cover assembly, the assembly comprising: a downhole tool; and a cover located closely about the tool, the cover not being laminated to the tool or an integral layer of any part of the tool, the cover comprised and configured to encompass at least part of an outer surface of the tool, and protect the tool from atmospheric humidity, and to not interfere with the tool's intended use downhole; and wherein the cover is comprised of one of the following: fluorinated ethylene propylene (PEP), polyolefin, PVC tubes, polyvinylidene fluoride (PVDF), silicone rubber, PLA, PGA, PVOH, PTFE (fluoropolymer) or Viton and is between 0.5 to 8 mil in thickness. This application discloses an assembly for use downhole in a hydrocarbon well, the assembly comprising: a downhole tool; and a protective cover located closely about the tool, the cover not being laminated to the tool or an integral layer of any part of the tool, the cover comprised and configured to encompass the tool, and to protect the tool from atmospheric humidity and other conditions, and which does not interfere with the tool's intended use downhole; and wherein the protective cover is degradable in an aqueous downhole fluid.

[0077] This application discloses a method of working on a hydrocarbon well having a vertical leg and a horizontal leg extending into a hydrocarbon bearing formation, the horizontal leg including a heel and a toe, the well having casing in the horizontal leg with an at least a 4 inch outer diameter (O.D.) and not more than a 6 inch outer diameter (O.D.), the casing having an inner diameter (I.D.) in the horizontal leg, and the casing having a series of casing patches reducing the ID of the casing in the horizontal leg, the method comprising: providing at least five retracted settable downhole tools, each having a protective cover, selecting five such retracted tools, each retracted tool narrow enough to be run through and past a 0.125 inch thick casing patch in the horizontal leg, and each tool having slips which are expandable enough so after the tool passes through the casing patch the slips can be expanded to an expanded slip configuration having an O.D. within the range of a radial inner limit of a 15% expansion of the retracted tool's O.D. and the inner diameter the casing and the expanded tool's slips are capable of setting against the casing of the horizontal leg and holding the tool to the casing during refracing to isolate an upper zone in the horizontal leg above the tool from a lower zone below the tool; the method further comprising: the steps of running the five tools with the protective cover thereon into the well and immersing the tools in a wellbore fluid in the well, produced from formation flow in the well having a pH less than 7, running the tools past the casing patch, setting the tools within the casing, and using the tools in isolating and refracing zones in the horizontal leg past one or more of the casing patches; the first tool being run in and set and used in isolating and refracing, then the second tool being run in and set above the first tool and used in isolating and refracing, then the third tool being run in and set above the second tool and used in isolating and refracing, then the fourth tool being run in and set above the third tool and used in isolating and refracing, then the fifth tool being run in and set above the fourth tool and used in isolating and refracing; waiting until after the tools are immersed in the downhole fluid in the well for the tools to degrade in the wellbore fluid enough to permit production of hydrocarbons from the well; and producing hydrocarbons from the horizontal leg after the tools are immersed in the downhole fluid in the well, without milling out or retrieving the five tools, the downhole fluid has a pH of 7 or less, or greater than 7.

[0078] This application discloses a transport container for shipping multiple cylindrical downhole tools, each having a cylinder length and a cylinder diameter, the container comprising: a rectangular body having sidewalls, a bottom wall, and an open top side defined by a perimeter; a lid, configured to fit within the open top side and to removably engage at least part of the perimeter when the lid is engaged, the container having an enclosed volume; and a rack located within the container, the rack configured to fit within the container's enclosed volume, the rack having a top plate and a spaced apart bottom plate, the top plate and bottom plate configured with multiple spaced apart hole pairs; wherein the holes have an inner diameter greater than the downhole tool's diameters, and the plates are spaced apart a distance less than the length of the downhole tools, the rack configured to hold the downhole tools in vertical alignment and the downhole tools spaced apart when the rectangular body is resting on a support surface, and wherein at least a portion of the each of the downhole tools extend above an upper surface of the top plate, wherein the lid or the body includes weather-stripping and the rack includes locators.

[0079] This application discloses a method of shipping cylindrical downhole tools including: providing a container; placing cylindrical downhole tools in the container; delivering the container containing the downhole tools to a well site; removing the downhole tools from the container for use at the well site; removing the container from the well site; and reusing the container by again placing tools in the container, delivering the loaded container to a well site and removing the container from a well site.

[0080] This application discloses fracing in oil and gas well are well known in the art. These methods use settable downhole tools, in some cases bridge or ball drop plugs. Tools used in completion and fracing may be degradable in a downhole fluid or may be nondegradable (millable). Applicant's protective wrap may be used on either degradable or nondegradable tools when they are run in and set downhole. The embodiments disclosed herein are modifications of known methods of completing and refracing oil and gas wells by using tool and wrap assemblies and transporting and using them as disclosed herein.

[0081] This application discloses a degradable assembly for use in a cased hydrocarbon well comprising: a settable downhole tool, the tool having a mandrel, a slip, and a cone; a protective coating for use about a settable downhole tool having a mandrel, slip or slips and cone or cones, comprising: the coating is degradable in the well's downhole fluid and covering an outer surface of at least the slip or slips and cone or cones, the coating adapted to degrade in a well's acidic aqueous downhole fluid and not interfere with running the tool into the well or interfere with the tool setting or sealing against the casing, the coated tool is adapted to be run into the well's casing, and then the coating to at least partially degrade in the well's downhole fluid, and then the tool to be set into and sealed against the casing; and, a moisture impermeable outer shell, the shell entirely enclosing the covered tool, and adapted to be easily removable from the covered tool prior to inserting the covered tool into the casing.

[0082] This application discloses a method of making a tool and wrap assembly for use at a cased well having acidic aqueous downhole fluid, comprising: providing a settable downhole tool, the tool having a mandrel, a slip and a cone; selecting a wrap material which is hydrolytically degradable in acidic aqueous downhole fluid, and which when shrunk about the tool, will provide a tool and wrap combination insertable within a casing and will provide a wrap about the tool which will not interfere with setting or sealing the tool against the casing; placing the wrap material about the outer surfaces of at least the slip and the cone; shrinking the wrap material about the tool so the wrap material becomes a shrunk wrap material about an outer surface of the slip and the cone, and provides a protective cover about the slip and the cone; and placing a moisture impermeable outer shell about the tool and wrap combination, the shell entirely enclosing the tool and wrap combination, and the shell being easily removable from the tool and wrap combination prior to insertion of the tool and wrap combination into the casing, providing a tool structural element which is degradable in acidic neutral or basic aqueous downhole fluids, the degradable structural element being at least one of a mandrel, cone or slip; wherein the resulting tool and wrap are comprised so the tool and wrap will degrade in the well's aqueous downhole fluids, and degradation of the tool's degradable structural element will release the tool from the casing, wherein the wrap material of the selecting step is a heat shrinkable wrap material, wherein the placing step includes placing the heat shrinkable wrap material about the entire outer surface of the tool's slips and cones; moving the wrapped tool through a thermal tunnel; using the thermal tunnel to apply enough heat to the wrap material as the wrap tool moves through the thermal tunnel to shrink the wrap material about the tool so the wrap material is secured to the tool and the wrap material provides a covered tool outer surface which is smooth enough to enable the covered tool to slide through sand on the bottom of a horizontal leg of the well with less friction than a similar tool without the wrap, namely, the wrap is longitudinally long enough to entirely cover the tool's slips and cones, and the wrap provides a covered tool outer surface which is smoother than a similar tool without the wrap, wherein the selecting step includes the step of selecting a wrap material between 0.5 to 7 mil thick, wherein the selecting step includes the step of selecting a wrap material between 1.5 to 5 mil thick, wherein the selecting step includes the step of selecting a wrap material between 0.2 to 3.5 mil thick, wherein the selecting step includes the step of: selecting a wrap material which will shrink unidirectionally; wherein the placing step includes applying the unidirectional wrap material about the tool so when the material is shrunk, it primarily shrinks radially about the tool and not longitudinally along the tool; and wherein the shrinking step includes shrinking the wrap material about the tool to produce a wrap covering at least the tool's cone and slip without the shrinking causing inserts or withers on the slip to penetrate the wrap material, wherein the selecting step includes selecting a wrap is comprised of a preformed tube having an inner diameter which is less than 1.5 inches larger than the outer diameter of the tool, the tube having a first end and a second end, both first and second ends being open, wherein the selecting step includes selecting a comprised of a preformed tube having an inner diameter which is less than one inch larger than the outer diameter of the tool, the tube having a first end and a second end, the first end being open and the second end being closed, wherein the selecting step includes selecting a comprised of a preformed bag having an inner diameter which is less than one half inch larger than the outer diameter of the tool, the tube having a first end and a second end, the first end being open and the second end being closed, wherein the selecting step includes selecting a wrap material which is primarily unidirectionally shrinkable and arranging the wrap material about the tool so wrap shrinkage primarily reduces the wrap's radius about the tool and does not primarily reduce the wrap's length along the tool, and so the wrap material's shrinkage does not cause the wrap to tear at the slip's inserts or withers.

[0083] This application discloses a method of making an assembly for use at a cased hydrocarbon well, the method comprising: providing a settable downhole tool, the tool having at least a mandrel, a slip, and a cone; providing a protective coating which is hydrolytically degradable in an acidic aqueous downhole fluid; covering outer surfaces of at least the slip and the cone with the protective coating, the coated tool adapted to be insertable within the well's casing, and the wrap adapted to degrade in the well's acidic, basic or neutral downhole fluid and not interfere with the tool setting or sealing against the casing; and, providing a moisture impermeable outer shell, the shell adapted to be easily removable from about the covered tool prior to inserting the covered tool into the casing.

[0084] This application discloses a transport container for shipping multiple cylindrical downhole tools, each tool having a cylinder length and a cylinder diameter, the container comprising: a container having sidewalls, a bottom wall, and an open top side defined by a perimeter; a lid, configured to fit within the open top side and to removably engage at least part of the perimeter when the lid is engaged, the container having an enclosed volume; a rack located within the container, the rack configured to fit within the container's enclosed volume, the rack having a top plate and a spaced apart bottom plate, the top plate and bottom plate configured with multiple spaced apart hole pairs; each hole has an inner diameter greater than each tool's outer diameter; the top and bottom plates are spaced apart a distance less than the length of the shortest downhole tool; the holes are configured and located and the container is sized to hold the tools in static spaced apart horizontal and vertical positions and alignment relative to the other tools and to the container; at least a portion of the each of the tools extends above an upper surface of the top plate; the container has a lid which may be opened and closed for access to the tools within the container; and wherein the container is adapted to be sealed against entry of moisture from outside the container to inside the container when the lid is closed, the container is configured and comprised of materials strong enough so the container is capable of being used to transport downhole tools to a well site, retrieved multiple times from wells, and reused multiple times to transport downhole tools to wells; and the container is comprised of recyclable materials.

[0085] This application discloses a method of transporting multiple assemblies, the method comprising: providing a shipping container containing a rack, the rack having a top plate and a spaced apart bottom plate, the top plate and bottom plate configured with multiple spaced apart hole pairs; wherein each hole has an inner diameter greater than each covered tool assembly's outer diameter, and the top and bottom plates are spaced apart a distance less than the length of the shortest downhole tool, wherein the holes are configured and located to hold the covered tool assemblies in horizontal and vertical alignment, keeping the covered tool assemblies apart, and wherein at least a portion of the each of the covered tool assemblies extends above an upper surface of the top plate; placing multiple covered tool assemblies into the shipping container and delivering the shipping container with the multiple covered tool assemblies to the well; removing the multiple covered tool assemblies from the shipping container at the well; and reusing the container to contain and transport additional downhole tools to the same or other wells.

[0086] Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. On the contrary, various modifications of the disclosed embodiments will become apparent to those skilled in the art upon reference to the description of the invention. It is therefore contemplated that the appended claims will cover such modifications, alternatives, and equivalents that fall within the true spirit and scope of the invention.