CA2592556A1 - Method and apparatus for plugging perforations - Google Patents

Method and apparatus for plugging perforations Download PDF

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Publication number
CA2592556A1
CA2592556A1 CA002592556A CA2592556A CA2592556A1 CA 2592556 A1 CA2592556 A1 CA 2592556A1 CA 002592556 A CA002592556 A CA 002592556A CA 2592556 A CA2592556 A CA 2592556A CA 2592556 A1 CA2592556 A1 CA 2592556A1
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CA
Canada
Prior art keywords
alloy
heating
perforations
heating tool
tube
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
CA002592556A
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French (fr)
Inventor
Homer L. Spencer
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
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Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of CA2592556A1 publication Critical patent/CA2592556A1/en
Abandoned legal-status Critical Current

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Classifications

    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21BEARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B29/00Cutting or destroying pipes, packers, plugs or wire lines, located in boreholes or wells, e.g. cutting of damaged pipes, of windows; Deforming of pipes in boreholes or wells; Reconditioning of well casings while in the ground
    • E21B29/10Reconditioning of well casings, e.g. straightening
    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21BEARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B33/00Sealing or packing boreholes or wells
    • E21B33/10Sealing or packing boreholes or wells in the borehole
    • E21B33/13Methods or devices for cementing, for plugging holes, crevices or the like
    • E21B33/138Plastering the borehole wall; Injecting into the formation
    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21BEARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B36/00Heating, cooling or insulating arrangements for boreholes or wells, e.g. for use in permafrost zones

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Mounting, Exchange, And Manufacturing Of Dies (AREA)
  • Safety Valves (AREA)

Abstract

Apparatus and method for plugging perforations in an oil or gas well. A bridge plug is formed in the casing below the perforations. A heating tool and a fusible alloy adjacent the heating tool is lowered into the well to a position above the bridge plug and adjacent the perforations. Heat is applied to melt the fusible alloy and pressure is applied to the molten material to force it through the perforations. The heating operation is terminated to allow the molten material to solidify and plug the perforations.

Description

TITLE

METHOD AND APPARATUS FOR PLUGGING PERFORATIONS
CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from United States Provisional Application Serial No.60/805,734 filed June 24, 2006 entitled PERFORATION PLUGGING TOOL AND
PROCEDURE (Spencer).

INTRODUCTION
This invention relates to method and apparatus for plugging perforations in an oil or gas well and, more .

particularly, to plugging an oil or gas well which utilizes a fusible alloy for plugging the perforations.
BACKGROUND OF THE INVENTION

in the oil and gas production industry, a perforated interval in the casing of the well is created to allow enhanced oil flow from the oil holding formation into the casing. The perforations are holes that extend from the inside of the well casing to the outside and are created by explosive shooting or other perforation techniques which techniques form no part of the present invention.

Following the long use of the perforations for oil or gas flow into the casing, water flow becomes a problem.
The water is undesirable since it mixes with the oil and must be removed from the oil at the surface. Furthermore, when water increases its flow through the perforations, the oil or gas flow may diminish to a point where the well is not longer commercially viable. In addition, the water flow may hinder the recovery of oil or gas from other areas of the formation. It therefore becomes advantageous to plug the previously formed perforations.

In our earlier United States Patent 6,828,531, the contents of which are incorporated herein by reference, ~.. -. : _ .._ _. _ there is disclosed a method and apparatus for plugging perforations using a squeeze procedure and a heating tool that melts a fusible alloy and squeezes the alloy into the perforations where the alloy cools and expands thereby closing the perforations and terminating flow therethrough.
The use of such a technique, while useful to close the perforations, also results in an residue of alloy being left within the well as a solid alloy plug across the casing.

The cost of the alloy to effect plugging in such an application is expensive. Further, the time to create the plugging in that application is unnecessarily time consuming.

It would advantageous to use less alloy for plugging the perforations and it further would be advantageous to enhance the efficiency of the plugging operation.

STJMMARY OF THE INVENTION

According to one aspect of the invention, there is provided a heating tool for use in plugging perforations in an oil or gas well comprising a heating element, a circumferential tube surrounding said heating element, a fusible alloy adjacent to and outside said circumferential tube and means for releasably connecting said circumferential tube and said fusible alloy to said heating element.

According to a further.aspect of the invention, there is provided a method of plugging perforations in the casing of an oil or gas well comprising the steps of forming a bridge plug in said casing at a position lower than the lowermost perforation sought to be plugged, lowering a heating tool and a fusible metal alloy to a position above said bridge plug and adjacent said perforations sought to be plugged, melting said alloy and applying pressure to said molten alloy to force said molten alloy through said perforations in said casing, lowering the temperature of said heating tool to allow said molten alloy to solidify within said perforations, removing said pressure from said molten alloy and withdrawing said heating tool from said oil or gas well.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
An embodiment of the invention will now be described, by way of example only, with the use of drawings in which:

Figure 1 is a diagrammatic cross-sectional illustration of an oil or gas well illustrating a perforated interval within the casing of an oil or gas well;

Figure 2 is a diagrammatic cross-sectional view of the oil or gas well of Figure 1 and illustrating the initial step of forming a bridge plug in the well to plug the well and a sand pad interval formed on the top of the bridge plug;

Figure 3 is a diagrammatic cross-sectional view of the oil or gas well of Figures 1 and 2 and further illustrating a heating tool lowered into the well by way of electrical line cable together with the fusible alloy material located on.the outside of the tool;

Figure 4 is a diagrammatic cross-sectional view similar to Figure 3 but illustrating pressure being applied on the molten alloy material thereby to force the alloy through the perforations; and Figure 5 is a diagrammatic cross-sectional view of the well of Figures 1-4 but illustrating the solidified alloy within the perforations and with the heating tool having been removed from the well.

DESCRIPTION OF SPECIFIC EMBODIMENT

Referring now to the drawings, an oil or gas well is generally illustrated at 10 in Figure 1 with the production casing 11 being cemented in by cement 12 which seals the production casing from the formation of interest which is an oil or gas bearing formation generally illustrated at 13.

Perforations 14 have been formed in the casing 11 and extend into the formation of interest 13.

It is desired to plug the perforations 14 and to terminate flow from the formation 13 through the perforations 14 and into the casing 11. To do so, a retrievable bridge plug 21 is set in the casing 11 below the lowest one of the perforations 14 as illustrated in Figure 2. The bridge plug 21 is formed within the casing 11 using wire line procedure which is known. A volume of sand 22 is then dumped into the casing 11 and on top of the bridge plug 21. The thickness of the sand layer 22 should extend upwardly to a position just below the lowermost one of the perforations of interest 14.

Referring to Figure 3, a heating and perforation plugging tool generally illustrated at 23 is lowered into the well 10 by electrical wire line cable 24 until it rests on the sand layer 22. Tool 23 is an electrical resistance type heater which has a heating coil diagrammatically illustrated at 30 which is connected to an electrical power supply (not shown) at the surface through electrical cable 24. A tube 30 is positioned outside the heating coil 31 and terminates at the lower end of the tool 23 with a flanged cap 32. The tube 30 is conveniently made from a relatively soft metal with high thermal conductivity such as aluminum although copper or brass or other metals are also contemplated to be useful. A latching mechanism generally illustrated at 33 maintains the tube 30 and flanged cap 32 in position relative to the heating coil 31 as will be described.

The layer 34 of meltable fusible alloy is formed around the circumference of the tube 30 and is in solid form as the heating tool 23 is lowered from the surface. The fusible alloy 34 is conveniently a bismuth/tin alloy although other such suitable alloys are also contemplated.
The volume of the alloy 34 surrounding the tube 30 is earlier calculated and is such that the perforations 14 will be completely filled when the alloy 34 is melted.

Referring to Figure 4, electric power is applied to the heating coil 30 through the electrical wire line cable 24. The heat is transmitted though the aluminum tube 31 and melts the fusible alloy material 34. Simultaneously with the melting of the alloy 34, pressure is applied to the melted alloy 34 by pumped water or by a compressed gas. The pressure forces the molten alloy 34 into the perforations 14 extending through the casing 11 and the cement 12 and into the formation 20.

Power to the heating tool 23 is then terminated and the latching mechanism 33 opens thereby allowing the ~.., _ . . :-_:. ... . . , _ _. _.
tube 31 and flanged cap 32 to be released from the heating tool 23 where they remain on the bridge plug 21 and sand 22.
The pressure remains on the molten alloy and the cessation of heating from the tool 23 causes the molten alloy 34 to solidify within the perforations 14. The bismuth/tin alloy 34 expands as it solidifies thereby creating a tight plug within the perforations 14 and blocking the entrance of the undesired water into the well 10. Following a sufficient time interval, the pressure on the alloy 34 within the well 10 is terminated and the heating tool 23 is withdrawn from the well 10. Any alloy remaining within the casing 11 is readily drilled out. The bridge plug 21 and sand 22 are likewise removed as is known. The solidified alloy 34 will remain in the perforations 14 thereby plugging the perforations 14.

Many modifications will readily occur to those skilled in the art to which the invention relates. It is desirable to have the tube 31 and solid alloy 34 brought into close proximity with the inside diameter of the casing 11 in order to enhance movement of the melted alloy into the perforations 14 and also to minimize the amount of alloy required for plugging the perforations 14. Accordingly, tubing 34 of various diameters could be accommodated by the heating tool 23. Likewise, while a latching mechanism 30 has been described, other mechanisms for allowing the release of the tubing 30 and alloy 34 such as shear pins, molded fusible metal which melts under the influence of heat from the heating tool 23 contemporaneously with the melting of the fusible alloy 34 used for.plugging the perforations, and the like are likewise contemplated.

The alloy material 34 on the outside of the releasable tube of the heating tool 23 as is described and illustrated may be formed on the outside of the tube 31 or it may conveniently be pre-molded in segments which segments would be slipped over the tube 31 in the desired quantities.
The segments would then rest against the flanged cap 32 but the operation of the heating tool 23 would be similar to the operation just described.

While a resistive type heating tool 23 has been described, it is contemplated that an inductive type heating tool such as that heating tool described in our United States Patent 6,825,531 would also be useful. There would be no need for a hollow center in such a tool but the use of induction for heating the fusible alloy 34 is contemplated to be useful for the present application.

Many further embodiments will readily occur to those skilled in the art to which the invention relates and the specific embodiments described should be taken as illustrative of the invention only and not as limiting its scope as defined in accordance with the accompanying claims.

Claims (16)

I CLAIM:
1. A heating tool for use in plugging perforations in an oil or gas well, said tool comprising a heating element, a circumferential tube surrounding said heating element, a fusible alloy adjacent to and outside said circumferential tube and means for releasably connecting said circumferential tube and said fusible alloy to said heating element.
2. A heating tool as in claim 1 wherein said circumferential tube is a thermally conductive metal material.
3. A heating tool as in claim 2 wherein said fusible alloy is formed around said heating tube.
4. A heating tool as in claim 1 wherein said means for releasably connecting said circumferential tube and said fusible alloy to said heating element is a latching means which in its closed position retains said tube and which opens to release said circumferential tube and said fusible alloy.
5. A heating tool as in claim 2 wherein said fusible alloy is formed in segments which are mounted around said circumferential tube.
6. Method of plugging perforations in the casing of an oil or gas well comprising the steps of forming a bridge plug in said casing at a position lower than the lowermost perforation sought to be plugged, lowering a heating tool and a fusible metal alloy to a position above said bridge plug and adjacent said perforations sought to be plugged, melting said alloy and applying pressure to said molten alloy to force said molten alloy through said perforations in said casing, lowering the temperature of said heating tool to allow said molten alloy to solidify within said perforations, removing said pressure from said molten alloy and withdrawing said heating tool from said oil or gas well.
7. Method as in claim 6 wherein said fusible alloy surrounds said heating tool.
8. Method as in claim 7 wherein said fusible alloy is formed on the circumference of said heating tool.
9. Method as in claim 7 wherein said fusible alloy is formed in segments and said segments are fitted around said heating tool.
10. Method as in claim 9 wherein the quantity of fusible alloy surrounding said heating is sufficient to fill said perforations in said oil or gas well.
11. Method as in claim 10 wherein said fusible alloy is a bismuth-tin alloy.
12. Method as in claim 11 wherein said heating tool further comprises a heating tube and said fusible alloy extends around the circumference of said heating tube.
13. Method as in claim 12 wherein said heating tube is made from aluminum.
14. Method as in claim 13 wherein said heating tool is a resistive type heating tool.
15. Method as in claim 13 wherein said heating tool is an inductive type heating tool.
16. Method as in claim 6 and further comprising depositing a layer of sand on top of said bridge plug.
CA002592556A 2006-06-24 2007-06-22 Method and apparatus for plugging perforations Abandoned CA2592556A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US80573406P 2006-06-24 2006-06-24
US60/805,734 2006-06-24

Publications (1)

Publication Number Publication Date
CA2592556A1 true CA2592556A1 (en) 2007-12-24

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CA002592556A Abandoned CA2592556A1 (en) 2006-06-24 2007-06-22 Method and apparatus for plugging perforations

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CA (1) CA2592556A1 (en)

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WO2011151271A1 (en) 2010-06-04 2011-12-08 Bisn Tec Ltd Method and apparatus for use in well abandonment
WO2014096858A2 (en) 2012-12-20 2014-06-26 Bisn Tec Ltd Apparatus for use in well abandonment
US10309187B2 (en) 2014-08-15 2019-06-04 Bisn Tec Ltd. Downhole fishing tool
CN110500060A (en) * 2019-09-26 2019-11-26 中铁隧道局集团有限公司 A kind of quick grouting device of segmentation protrusive drilling rod, system and grouting method
CN112228002A (en) * 2020-09-09 2021-01-15 大庆康盛石油节能科技开发有限公司 Plugging device for near wellbore zone of perforated oil layer
EP3779120A1 (en) 2016-05-06 2021-02-17 BiSN Tec Ltd Chemical heat sources for use in down-hole operations
EP3789582A1 (en) 2016-05-24 2021-03-10 BiSN Tec Ltd Down-hole chemical heater and methods of operating such
US11199067B2 (en) 2017-04-04 2021-12-14 Bisn Tec Ltd Thermally deformable annular packers
US11578556B2 (en) 2014-04-04 2023-02-14 Bisn Tec Ltd. Well casing/tubing disposal
US11867020B2 (en) 2017-11-17 2024-01-09 BiSN Tec. Ltd. Expandable eutectic alloy based downhole tool and methods of deploying such

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US8857513B2 (en) 2012-01-20 2014-10-14 Baker Hughes Incorporated Refracturing method for plug and perforate wells
US10760374B2 (en) 2016-09-30 2020-09-01 Conocophillips Company Tool for metal plugging or sealing of casing
US10738567B2 (en) 2016-09-30 2020-08-11 Conocophillips Company Through tubing P and A with two-material plugs
WO2018063829A1 (en) * 2016-09-30 2018-04-05 Conocophillips Company Tool for metal plugging or sealing of casing
EP3592939B1 (en) 2017-03-11 2023-08-30 ConocoPhillips Company Helical coil annular access plug and abandonment
GB2579349B (en) * 2018-11-16 2021-05-19 Equinor Energy As A-annulus cementing without pumping cement
MX2022006306A (en) * 2020-01-17 2022-06-22 Halliburton Energy Services Inc Heaters to accelerate setting of expandable metal.
EP4143416A4 (en) * 2020-04-30 2024-05-22 Wellstrom AS Method and apparatus for plugging
EP4248060A1 (en) * 2020-11-23 2023-09-27 BiSN Tec Ltd Multi-trip annular seal repair method and associated equipment
GB202112492D0 (en) * 2021-09-02 2021-10-20 Head Philip All metal-to-metal casing patch
CN117948074A (en) * 2022-10-19 2024-04-30 中国石油天然气集团有限公司 Casing nipple and tubular structure

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US20060144591A1 (en) * 2004-12-30 2006-07-06 Chevron U.S.A. Inc. Method and apparatus for repair of wells utilizing meltable repair materials and exothermic reactants as heating agents

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US10801301B2 (en) 2010-06-04 2020-10-13 Bisn Tec Ltd Releasable alloy system and method for well management
EP3604732A1 (en) 2010-06-04 2020-02-05 BiSN Tec Ltd Method and apparatus for use in well abandonment
WO2011151271A1 (en) 2010-06-04 2011-12-08 Bisn Tec Ltd Method and apparatus for use in well abandonment
EP3176360A1 (en) 2010-06-04 2017-06-07 Bisn Tec Ltd Method and apparatus for use in well abandonment
US9708882B2 (en) 2010-06-04 2017-07-18 Bisn Oil Tools Method and apparatus for use in well abandonment
EP3241982A1 (en) 2012-12-20 2017-11-08 Bisn Tec Ltd Apparatus for use in well abandonment
US10053950B2 (en) 2012-12-20 2018-08-21 Bisn Tec Ltd Controlled heat source based down-hole plugging tools and applications
US10113386B2 (en) 2012-12-20 2018-10-30 Bisn Tec Ltd. Apparatus for use in well abandonment
US10145203B2 (en) 2012-12-20 2018-12-04 Bisn Tec Ltd System and method of using heat sources and alloys in down-hole applications
US10161215B2 (en) 2012-12-20 2018-12-25 Bisn Tec Ltd Apparatus for use in well abandonment
EP3179029A1 (en) 2012-12-20 2017-06-14 Bisn Tec Ltd Apparatus for use in well abandonment
US11525329B2 (en) 2012-12-20 2022-12-13 BiSN Tec. Ltd. Apparatus for use in well abandonment
WO2014096858A2 (en) 2012-12-20 2014-06-26 Bisn Tec Ltd Apparatus for use in well abandonment
EP3179030A1 (en) 2012-12-20 2017-06-14 Bisn Tec Ltd Heat sources and alloys for use in down-hole applications
US11578556B2 (en) 2014-04-04 2023-02-14 Bisn Tec Ltd. Well casing/tubing disposal
US11053771B2 (en) 2014-08-15 2021-07-06 Bisn Tec Ltd. Downhole fishing tool
US10370931B2 (en) 2014-08-15 2019-08-06 Bisn Tec Ltd. Methods and apparatus for use in oil and gas well completion
US10309187B2 (en) 2014-08-15 2019-06-04 Bisn Tec Ltd. Downhole fishing tool
US10961806B2 (en) 2014-08-15 2021-03-30 Bisn Tec Ltd Downhole well tools and methods of using such
EP3913185A1 (en) 2016-05-06 2021-11-24 Bisn Tec Ltd Chemical heat sources for use in down-hole operations
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EP3789582A1 (en) 2016-05-24 2021-03-10 BiSN Tec Ltd Down-hole chemical heater and methods of operating such
US11401776B2 (en) 2016-05-24 2022-08-02 Bisn Tec Ltd. Downhole operations relating to open hole gravel packs and tools for use therein
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US11634966B2 (en) 2016-05-24 2023-04-25 BiSN Tec. Ltd. Combined well plug/chemical heater assemblies for use in down-hole operations and associated heater cartridges
US11199067B2 (en) 2017-04-04 2021-12-14 Bisn Tec Ltd Thermally deformable annular packers
US11867020B2 (en) 2017-11-17 2024-01-09 BiSN Tec. Ltd. Expandable eutectic alloy based downhole tool and methods of deploying such
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FZDE Discontinued

Effective date: 20100622