MXPA01008088A - Method of releasing stuck pipe or tools and spotting fluids therefor - Google Patents

Abstract

Aphron-containing spotting fluids and their use in releasing pipe or tools stuck in the filter cake on the sides of a borehole are disclosed. The spotting fluids comprise a liquid, either aqueous, oleaginous, or mixtures thereof, a viscosifier which imparts a low shear rate viscosity to the fluids of at least 10,000 centipoise, an aphron-generating surfactant, and aphrons. The spotting fluids are used in a conventional method of releasing pipes or tools stuck in the filter cake on the sides of a borehole during conventional drilling or well servicing operations.

Description

METHOD FOR RELEASING STAMPED AND FLUID MARKING TUBES OR TOOLS The patent application is a continuation request in part of the serial US patent application No. 08 / 800,727, completed on 02/13/97, with PCT of international application No PCT / US98 / 02566 completed on 10/02/98 and serial US patent application No. 09/121, 713, completed on 07/24/98; for each of which priority is claimed here. BACKGROUND OF THE INVENTION It is described in US Serial Patent Application No. 08 / 800,727, filed on 02/13/97 co-appended, which is incorporated herein by reference, the PCT of US serial patent application No. PCT. / US98 / 02566, completed on 02/10/98 co-appended, which is incorporated herein by reference, and US Serial Patent Application No. 09 / 121,713, completed on 07/24/98 co-appended, which is incorporated herein by reference, well drilling and maintenance fluids exhibiting a high and low slip velocity viscosity (hereinafter referred to as "LSRV") and containing aphrons (i.e. microbubbles of a gas.) Preferred fluids have aphrons that are generated by ingesting air in contact with the fluids and creating the aphrons due to the pressure drop that occurs when the fluid flowing out of the drill bit. the inert gases like nitrogen and Carbon dioxide can be incorporated into fluids instead of relying on ingested air or can be generated in-situ by means of reactive components such as carbonates and acids. In addition, the aphrons can be generated on the surface of the well and incorporated into the fluid or can be created on the surface in the fluid.

This invention relates to a method and composition for facilitating the release of a tube or a tool stuck within a bore, preferably a differentially jammed tube. The old thing A clogged pipe or tool can be defined as a drill pipe, drilling clamps, drill bits, stabilizers, reamers, boxes, pipe, measurements while drilling, logging tools, etc., inadvertently become immobile in a well hole. The term "stuck pipe" is used in the industry as a convenient term to cover the clogging of all the equipment and it is generally understood that it is not literally restricted to pipes. Clogging can happen when the drilling is in progress, when the tube and box are working in the hole or when the drilling tube is lifted. There are numerous causes of stuck tube: some occur on a regular basis, some may be peculiar to a particular area and some may be unique. The industry convention catalogs the causes either as differential or mechanical clogging. It is believed that differential clogging occurs through the following mechanism. During most drilling operations, the hydrostatic pressure exerted by a drilling mud column is greater than the fluid formation pressure. In permeable formations, mud filtration flows from the hole to the rock and accumulates a mud crust. A differential pressure exits through the mud crust which is equal to the difference between the pressure of the mud column and the pressure of the formation. When a pipe is central to a hole, the hydrostatic pressure due to the overbalance of the mud acts in all directions around it. However, if the tube touches the mud crust, the overbalance of the mud acts to push the pipe into the mud, thus increasing the contact area between the pipe and the mud. Filtration is still expelled from the mud crust between the tube and the formation, which shakes the mud and allows the tube to penetrate more and thus further increase the contact area. If the pressure difference is high enough and acts on a large area, the tube may get stuck. Differential binding usually occurs when the tube has been motionless for a period of time, for example, when making a connection or during an investigation. Differential binding can be a particular problem when drilling empty deposits due to the associated high overbalance. The force required to pull a clogged free tube differentially depends on the following factors: a. The difference in pressure between the hole and the formation. Any overbalance that is added to the lateral forces that may exist due to the deviation of the hole. b. The surface area of the tube embedded in the mud crust. The thicker the mud or the larger the diameter of the pipe, the greater this area will have to be. c. The bond that develops between the tube and the mud crust is a very significant factor, since it is directly proportional to the binding force. This can include friction, cohesive and adhesive forces. This tends to increase over time, which makes it more difficult to pull the free tube. The differential clogging can be distinguished from other forms of clogging, such as mechanical clogging. The mud circulation is not interrupted since there is no obstruction in the hole to stop the flow, as it would be in the case of the tube stuck due to the union or cavity of the tube. It is not possible to move or rotate the tube in any direction. When a tube gets stuck, the piercer attempts to release it by mechanical movement, for example, by pulling it, shaking it, turning it, or, if the tube was moving just before the binding, try to move it in the opposite direction. Frequently the tube can not be released with this and, of course, there is a limit to the force that can be applied, since too much force could fracture the tube and make the situation worse. If the tube is still clogged, an agent is sometimes applied to release the tube, as a marking fluid. The labeling fluids are chemically active mixtures, which may be oil-based or water-based, including emulsions, which are placed over the jammed region in an attempt to release the tube, it is believed that this acts upon attacking the iodine scab. They are placed by pumping them into the hole in the jammed region in the form of a piece known as a pill. The pill usually contains enough material to cover the clogged area and extend slightly further over a total area of 1.5 times the area of the clogged area. The required volume of the pill to achieve this is almost 100 bbl. Almost always the pills are left soaking until the tube is released or attempts to release it are abandoned. However, it is also common to use smaller or larger pills and use two or more pills, one after the other after waiting for a period of soaking between the pills, and moving the pill past the clogged area a little while pumping . The marking fluids are usually sold as proprietary blends by companies that market in this area, often without disclosing their chemical components. However, some marking fluids are based on asphaltenic compounds and some on glycols, glycerols, alcohols and fatty acids and derivatives of said compounds. Traditionally, the density of the pill has increased in a manner similar to that of the sludge, using solid agents of particular weight such as barite, with viscosifiers to avoid fixation and equalize the density of the marking fluid to the density of the drilling fluid that It was being used until the moment when the tube got stuck. For example, if the drilling fluid had a density of 14 pounds / gallon (ppg) the marking fluid should increase the weight, as with the barite, to result in a density of the marking fluid of 14 ppg. Nevertheless, the equality of the density is not always considered necessary nor is it always the best procedure. There are many marking fluids known in the art. In cases where environmental problems do not prohibit their use, diesel fuel has been used with some success. For many years, asphalt-based marking fluids, such as BLACK MAGIC SFT ™ and BLACK MAGIC ™ products sold by Baker-Hughes, are also used with some success. In the COSOS where the marking fluids with base of asphalt, diesel fuel, mineral fuel or other oil based ones can not or should not be used, there are many other commercially available fluids that are not harmful to the environment and that have been used in an attempt to release jammed tubes, sometimes only with limited success. For example, the use of polyalphaolefin as a lubricant / labeling fluid is described in U.S. Patent No. 4876,017, to David O. Trahan, et al., Said material is marketed by The Coastal Mud Company under the trademark COASTALUBE ™. .

U.S. Patent No. 5,002,672 to James R. Hayes, et al., Is another example of a marking fluid (marketed by Turbo-Chem International, Inc. of Lafayette, La.) Consists of the use of a glycerophosphoric acid ester and a polyacyloxy polycarboxylic acid ester of mono and / or diglycerides, in combination with other viscosifiers and sealing agents. U.S. Patent No. 4,964,615 to Heinz Mueller, et al., Discloses another marking fluid utilizing acid alkyl esters or mixtures of esters. U.S. Patent No. 5,608,879 to Hailiday et al., Discloses the use of olefin isomers containing at least one double bond that is internally located within the hydrocarbon as a marking fluid additive. The registration of the invention established by law No. H1000, of Patel et al, describes the use of synthetic hydrocarbons consisting of a chain of oligomers synthesized from one or more olefins containing a chain length of C2 to C14 in which the oligomers have an average molecular weight of from 120 to 1000. In this matter, many other commercially available labeling fluids are known, for example, the COASTALSPOT marking fluid (a polyol ester) sold by Coastal Mud Company, Abbeville, La. , ENVIRO-SPOT ™, the PETROFREE ™ ester and the BARO-SPOT ™ marking fluids that you commercialize Baroid Drilling Fluids, Inc. of Houston, Tex., The CESCO A-25 SPOT ™ product marketed by Cesco Chemicals, Inc. of Lafayette, La., The PIPE-LAX ™ product (a glyceride) that markets Ml Drilling Fluids, Inc. ., and the product VL-250 (a mixture of cyclic terpenes Cío) sold by Integrity Industries. The ENVIRO-SPOT ™ product is a mixture of emulsifiers, lubricants, gelling agents and other materials. The product BARO-SPOT ™ is a mixture of surfactants, lubricants and viscosifiers. SURFYNOL ™ 440, an acetylene d polyol sold by Air Products, Inc. BEXR-2000 is a polyglycol marketed by Baroid Drilling Fluids, Inc. MONA ™ 939 is a phosphate ester sold by Mona Industries, Inc. It is also known ( the KOPLUS LL ™ material marketed by Gait International of Dublin, Ireland) utilizes citric acid in combination with organic or inorganic salts (including potassium chloride) to release the clogged tube. However, each available marking fluid has had limited success in releasing stuck tubes. SUMMARY OF THE INVENTION It has been found that tubes and tools stuck in a hole can be released using as marking fluid a liquid having one or more viscosifiers that impart a low slip velocity viscosity of at least 10,000 centipoise to the fluid, a surfactant that generates aphron, and aphrons, preferably, the aphrons are generated on the surface before placing the marking fluid in the location of the stuck tube or tool. The method for releasing the stuck tube or tool is to locate the point at which the tube or tool is stuck against the formation penetrated by the hole, and to introduce a volume of marking fluid to the depth of the tube point or the tube. A tool stuck in that the volume of the marking fluid is sufficient to move the fluid in the hole over the entire jammed surface. Therefore, an object of the invention is to incorporate aphrons in the marking fluids to improve their performance. Another object of the invention is to prepare marking fluids having a low slip velocity viscosity of at least 10,000 centipoise containing aphrons.

Another object of the invention is to provide a method for releasing a stuck tube or tool into a hole in which the novel marking fluid of this invention is placed in the location of the hole in which the tube or tool was jammed. These and other objects of the invention will become apparent to those skilled in the art upon reading the specifications and claims. Although the invention is susceptible to various modifications and alternative formsNext, specific incorporations will be described in more detail and will be shown by means of examples. However, it should be understood that it is not intended to limit the invention to the particular forms described, on the contrary, the invention covers all modifications and alternatives that are within the spirit and scope of the invention, as expressed in the appended claims . The compositions may consist of, consist essentially of or consist of the established materials. The method can consist of, consist essentially of or consist of the established steps with the established materials. Preferred Embodiments of the Invention In its broader aspects, the present invention is directed to the incoforation of aphrons in the marking fluids that are used to release tubes or tools stuck in a hole. The base of the marking fluid may be a marking fluid known in this field as exemplified in the patents and fluids set forth above, or may be a newly prepared marking fluid having the desired characteristics. Stable marking fluids containing aphron are obtained by increasing the viscosity of low slip velocity (LSRV) of the marking fluid to at least 10,000 centipoise, preferably to at least 20,000 centipoise, and better still to 40,000 centipoise. Because the stability of the aphrons is improved as the LSRV increases, an LSRV of several hundred thousand is preferable. The aphrons are obtained by incubating (1) a surfactant that generates aphron in the marking fluid and from there generate the aphrons in the marking fluid or (2) when generating the aphrons in a liquid compatible with the marking fluid and Mix the fluid containing aphron with the marking fluid. Félix Sebba's book entitled "Bilíquidas foams and foams - Aphrons", John Wiley & amp; amp;; Sons, 1987, which is incorporated herein by reference, is an excellent source in the preparation and properties of aphrons, that is, microbubbles. An aphron is composed of a center, which is generally spherical, of an internal phase, usually gas, encapsulated in a thin structure. This structure contains surfactant molecules placed in such a way that they produce an effective barrier against coalescence with adjacent aphrons. The aphrons can be generated by means known in this field. In addition to the methods described by Felix Sebba in the above-mentioned book, other methods are described in U.S. Patent No. 5,314,644 to Michelson et al, which is herein incorporated by reference, in U.S. Patent No. 5,397,001 to Yoon et al., which is hereby incorporated by reference, in U.S. Patent No. 5,738,118 to Kolaini, which is incorporated herein by reference, in U.S. Patent No. 5,352,436 to Wheatley et al., which is hereby incorporated by reference, and in U.S. Pat. 4,162,970; 4,112,025; 4,717,515; 4,304,740; and 3,671,022, which are incorporated herein by reference. The aphrons will be produced by the pressure drop while the marking fluid is pumped through the bit.

The gas that is used to create the aphrons can be any appreciable gas that is not soluble in the liquid phase of the fluid. Thus, the gas may be air, nitrogen, carbon dioxide, organic gases, and the like, including air encapsulated in the fluid during mixing. The marking fluid is composed of a liquid that has incoforated a viscosifier so that the marking fluid has an LSRV of at least 10,000 centipoise, a surfactant that generates aphron, and aphrons, and optionally, a release agent. Any viscosifier that improves the viscosity of the liquid phase that surrounds the aphrons will improve the stability; however, it has been found that those viscosifiers that provide the high LSRV of the present invention have the unique property of delaying the coalescence of the aphrons for very long periods of time. The use of aphrons (or microbubbles) in systems under high pressures as in the present use has never been described. It is well known that the hydrostatic pressure of the fluid in a hole increases as the depth increases. Therefore, although the size of the microbubbles is compressed, it is believed that the high LSRV prevents coalescence of the aphrons. In this regard, the aphrons may have a larger size on the surface of the well, as long as they are individual bubbles, since they will decrease in size to the aphron size range of less than 100 micrometers as they are pumped into the hole. The marking fluid may contain more than one liquid, such as a liquid dispersed or emulsified in another base liquid in which it is relatively insoluble, such as water-in-oil dispersions or emulsions, oil-in-water dispersions or emulsions, and the like, wherein the "water" phase is an aqueous liquid or a liquid soluble in water and in which the "oil" phase is a liquid insoluble in water. The base liquid can be either an aqueous liquid or an oily liquid. When the base liquid is an aqueous liquid, the marking fluid will have a continuous aqueous phase. When the base liquid is an oily liquid, the marking fluid will have a continuous oil phase. The aqueous base liquid can be fresh water, sea water, or salt water containing soluble salts such as sodium chloride, potassium chloride, calcium chloride, magnesium chloride, sodium bromide, potassium bromide, calcium bromide, bromide. zinc, form sodium, form potassium, form cesium, and mixtures of them. The salt water may contain one or more soluble salts at any desired concentration until saturation. Even highly saturated salty waters can be used where a fluid without solids is not desired or required. The oil-base phase can be any water-insoluble organic liquid that can be viscosified to the desired extent and, when placed in a hole in the location of a stuck tube or tool, will cause the mud crust to break or release the pressure differential to release the stuck tube or tool. Exemplary oleaginous liquids include liquid petroleum fuels or fractions thereof, vegetable oils and various synthetic organic liquids such as unsaturated hydrocarbon oligomers, carboxylic acid esters, phosphoric acid esters, ethers, polyalkyleneglycols, dkjlymes, acetates, and the like. The base liquid, aqueous or non-aqueous, may contain other materials, either liquid or solid, that are soluble or insoluble. Means are known for improving the viscosity of low slip velocity of liquids. Thus, aqueous systems can be viscosified with certain polymers that produce a fluid that exhibits sliding slimming behavior, high stress production. The bipolymers produced by the action of the bacteria, fungus, or other microorganisms on a suitable substrate are particularly useful. Exemplary bipolymers are the polysaccharides produced by the action of the bacteria Xanthomonas compestris, which are known as xanthan gums. These are commercially available from different sources, including: Kelko Oil Field Group, Inc., under the trademark "Xanvis" and "Kelzan"; Rhone-Poulenc Chimie Fine, under the trademark "Rhodopol 23-p"; Pfizer Inc., under the registered trademark "Flocon 4800C"; Shell International Chemical Company of London, U.K., under the registered trademark "Shellflo ZA"; and Drilling Specialties Company, under the trademark "Flo zan". See for example, U.S. Patent No. 4,299,825 and U.S. Patent No. 4,758,356, which are hereby incorporated by reference. Other useful bipolymers in the fluids of this invention are the famous welan gums produced by the fermentation with a microorganism of the genus Alcaligenes. See, for example, U.S. Patent No. 4,342,866, which is hereby incorporated by reference. Gellan gums are described in U.S. Patent No. 4,503,084, which is hereby incorporated by reference. Schleroglucan polysaccharides produced by the fungus of the genus selerotium are described in U.S. Patent No. 3,301,848, which is hereby incorporated by reference. The commercially available schleroglucan is sold under the trademarks "Polytran" of Pillsbury Company and "Actigum CS-11" of CECA S.A. The succinogiyean polysaccharides are produced by growing a slime-forming species of Pseudomonas, Rhizobium, Alcaligenes or Agrobacterium, for example, Pseudomonas sp. NCIB 11264, Pseudomonas sp. NCIB 11592, or agrobacterium radiobacter NCIB 11883, or mutants, as described in European Patent No. A40445 or A138255. The succinoglycan bipolymer is sold by Shell International Chemical Company of London, U.K., under the trademark "Shellflo-S". Other water-soluble polymers that impart rheology of slimming slurries to aqueous fluids include derivatives of alginic acid, sodium alginate, sodium calcium alginate, calcium ammonium alginate, and the like. An in situ degradation of solutions of sodium alginate with a divalent cation, such as with calcium salt, produces high viscosities of low sliding speed. The minimum concentration of polymer that is required to increase the viscosity of low fluid velocity can be determined by a routine test. Therefore, the minimum concentration will be an amount sufficient to impart the viscosity of low slip velocity to the fluid. In general, the fluids will contain a concentration of almost 1.4 kg / m3 (0.5 ppb) to almost 28.5 kg / m3 (10 ppb), preferably from almost 2.85 kg / m3 (1.0 ppb) to almost 14.3 kg / m3 (5.0 ppb). Certain aqueous liquids may be viscosified with a combination of dispersed smectite clay, such as sodium bentonite, and a mixed metal hydroxide as set forth in U.S. Patent Nos. 4,664,843, and 5,094,778. In fact, aqueous fluids with high LSRV can be obtained by properly flocculating dispersions of bentonite mud or by incoping 25 ppb or more unattended sodium bentonite. Oleaginous liquids can be viscosified with various materials such as organophilic muds, colloidal fumed silicas, resins, polymers, dimer acids, fatty amino salts of anionic polysaccharides, fatty acid salts of cationic polysaccharides, and mixtures thereof, as is known in this countryside. U.S. Patent No. 4,816,551 to Oehier discloses an amide resin for use with organophilic slurries to produce more slip thinning fluids. The surfactant that generates aphron for use in the marking fluids of this invention must be compatible with the base liquid and the viscosifier, so that the LSRV of the fluid can be maintained. The surfactant may also have one or more unstable stabilizers, such as alkyl alcohols, fatty alkanolamides and alkyl betaines. Generally, the alkyl chain will contain from 10 to 18 carbon atoms. The surfactant that generates aphron can be anionic, non-anionic, or cationic, depending on the compatibility with the viscosifier. The annual publication "McCutcheon's Emulsifiers &; Detergents ", from MC Publishing Co., McCutcheon Division, lists many surfactants and their manufacturers.The anionic foam surfactants are alkyl sulfates, alofinalpha sulfonates, alkyl ether (alcohol) sulphates, refined petroleum sulfonates and mixtures of Generally these surfactants will contain an alkyl chain having from 10 to 18 carbon atoms, preferably from 12 to 16 carbon atoms.The preferred nonionic surfactants are the ethoxylated alcohols and the amino oxides having a chain length of alkyl of 10 to 18 carbon atoms, preferably 12 to 16 carbon atoms Fluorocarbon based surfactants are preferred for systems in which the oil liquid is the continuous phase Representative commercially available surfactants are: ) alkyl sulfates - brand DUPONOL ™, Witco Cof, brand RHODAPON ™, Rh? ne-Poulenc, brand STEOL ™, Stepan cO. (2) sulfonates olefin alph a - WITCONATE ™ AOS and 3203, Witco Cof .; STEPANTAN ™ AS-40, Stepan Co .; RHODACAL ™ A-246/6, Rhone-Puolenc; (3) alkyl ether sulfates - WITCOLATE ™ brand, Witco Cof .; brand RHHODAPLEX ™, Rhone-Poulenc; brand SULFOCHEM ™, Chemron Cof; (4) petroleum sulfonates-BASE ™ brand, Keil Chemical; MONALUBE ™ 605, Mona Industries Inc .; WITCONATE ™ ÑAS -8, Witco Cof .; (5) ethoxylated alcohols - brand ALFONIC ™, Vista Chemical Co .; brand SURFONIC1"', Huntsman Cof., brand NEODOL ™, Shell chemical Co .; (6) amino oxides - brand AMMONYX ™, Stepan Co .; brand RHODAMOX ™, Rhone-Poulenc; brand CHEMOXIDE ™, Chemron Cof .; (7 ) Betaines - brand CHEMBETAINE ™, Chemron Cof, brand REWOTER1C ™, Witco Cof .; brand MIRATAINE ™, Rhope-Poulenc; (8) fluorocarbon-based surfactants - brand FLUORAD ™, 3 M Co., brand ZONYLtm 'EI Dupont De Nemours &Co; (9) fatty alkanolamides - brand ALKAMIDE ™, Rhone - Poulenc, brand AMIDEX ™, Chemron Cof .; brand WITCAMIDE ™, Witco Cof. In U.S. Patent No. 5,639,443 to Schutt et al. here as reference, it is described that suitable surfactants for forming microbubbles include block copolymers of polyoxypropylene polyoxyethylene, sugar esters, fatty alcohols, aliphatic amino acids, aliphatic esters of hyaluronic acid, aliphatic ester salts of hyaluronic acid, dodecyi poly (ethyleneoxy) ) ethanol, nonylphen oxy poly (ethyleneoxy) ethanol, hydroxy ethyl starch, hydroxyethyl starch fatty acid esters, dextrans, dextran fatty acid esters, sorbitol, sorbitol fatty acid esters, gelatin, whey albumins, phospholipids, polyoxyethylene fatty acid esters, such as polyoxyethylene stearates, ethers of fatty alcohol polyoxyethylene, fatty acid esters sorbitan polyoxyethylated, glycerol polyethylene glycol oxystearate, glycerol polyethylene glycol ricinolate, ethoxylated soybean sterols, ethoxylated beaver oils and hydrogenated derivatives, cholesterol, fatty acids having 12 to 24 atoms carbon or salt, and surfactants that form ordered structures in solution to produce non-Newtonian viscoelastic surface stresses, such as sugar-based surfactants and protein and glycoprotein surfactants. A preferred type of said surfactant has sugar or other carbohydrate front group, and a subsequent hydrocarbon or fluorocarbon group. A large group of sugars is known which can function as a front group, including glucose, sucrose, mannose, lactose, fructose, dextrose, aldose and the like. The subsequent group preferably has from 2 to 24 carbon atoms, preferably a fatty acid group (branched or unbranched, saturated or unsaturated) covalently attached to the sugar moiety through an ester linkage. A preferred surfactant mixture includes a nionic surfactant or other surfactant in combination with one or more of the non-Newtonian viscoelastic surfactants. In U.S. Patent No. 5,352,436, from Wheatley et al., which is incorporated herein by reference, discloses that suitable suffixers for forming stabilized gas microbubbles consist of a first soluble surfactant and a second dispersible surfactant. The first suitable surfactants include fatty acid esters of polyoxyethylene, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, polyoxyethylene soFitan monooleate, and mixtures thereof. Suitable second surfactants, which are different from the former, include sorbitan monostearate, sorbitan monooleate and mixtures thereof. U.S. Patent No. 4,684,479, to D'Arrigo, which is hereby incorporated by reference, discloses mixtures of surfactants which are composed of (a) a member selected from the group consisting of glycerol monoesters of saturated carboxylic acids containing from 10 to 18 carbon atoms and aliphatic alcohols containing 10 to 18 carbon atoms; (b) an ester of sterol-aromatic acid; (c) a member selected from the group consisting of sterols, tefens, bile acids and alkali metal salts of bile acids; (d) a member selected from the group consisting of sterol esters of aliphatic acids containing from 1 to 18 carbon atoms; sterol esters of sugar acids; esters of sugar acids and aliphatic alcohols containing from 10 to 18 carbon atoms; sugar esters and aliphatic acids containing from 10 to 18 carbon atoms; sugar acids; saponins; and sapogenins; and (e) a member selected from the group consisting of glycerol, glycerol di or triesters of aliphatic acids containing from 10 to 18 carbon atoms and aliphatic alcohols containing from 10 to 18 carbon atoms; said components are present in said mixture in a portion of radius a: b: c: d: e of 2-4: 0.5-1.5: 0.5-1.5: 0-1.5: 0-1.5.

Fluorosurfactants include, but are not limited to, (i) fluorinated telomers, (ii) amphoteric fluorosurfactants, (iii) polyfluorinated amino amines, (iv) polyacrylamides ethylthio fluoroalkyl, (v) perfluoroalkyl ethylthiopolyacrylamides, (vi) derivatives of 1- propanaminium, 2-Hydroxy-N, N, N-trimethyl-3-gamma-omega-perfluoro- (C6-C2o-alkyl) thio, chloride, (vii) fluoroalkyl sodium sulfonate, and (viii) sodium salts of 1-propanesulfonic acid, 2-metho-, 2--. { [1-oxo-3 [gamma, -omega, -perfluoro-Ci6-C26-alkyl) thioi-propylr amino? derivative. The concentration of surfactant that generates aphron that is required is usually less than the critical concentration of micelles (CMC) of the surfactant or surfactant mixture. By determining the density reduction that occurs when the aphrons are generated in the fluid, an indication of the volume of aphrons that is generated can be obtained. Foam of the fluid, which is undesirable, can occur if the concentration of surfactant that generates aphron is excessive. It has been determined that the concentration of surfactant can be increased without any adverse effect on the fluid, as the LSRV increases. Therefore, the concentration of surfactant that generates aphron, which can be determined by means of a routine test, is the amount that is required to generate sufficient aphrons to give the desired density reduction, but which is insufficient to create a foam long-lasting on the surface of the fluid. The density of the marking fluids can be adjusted, as required, by the addition of weight materials or the addition of soluble salts to the fluids, as is well known in the art. Preferably, the weight material is added to the fluid before the generation or incoforation of aphrons, thus adjusting the final density of the marking fluid containing aphron to the density desired by the concentration of aphrons. In addition, the marking fluid may contain other known functional materials, such as emulsifiers, moisture agents and the like. When a drilling rod or other tool in the hole becomes stuck in the wet fluid solids in a wall of the hole in a permeable formation, and it is believed that the clogging is due to differential hydrostatic pressure by the rod of the drill. The perforator, the tube or tool can be released by substantially filling the exterior of the drill hole of the drilling machine in the permeable formation with the marking fluid of this invention. The marking fluid remains in contact with the mud for a period of time sufficient for the fluid to alter and move the mud crust in some way, to cause the mud to dehydrate or sink and crack so that the fluid penetrates the mud of solid coughs of fluid wet with water. Said fluid flow from the hole in the mud through the resulting cracks, at least must partially reduce the differential pressure by the rod tube or other tool. The marking fluid can be kept in contact with the slurry for an additional time for subsequent sinking, cracking and penetration of the sludge so that the marking fluid completely penetrates the sludge and the surface of the permeable formation is wetted. By wetting the surface of the permeable surface with the marking fluid, the adhesion forces between the wet solids mud and the face of the permeable formation are reduced, so that the mud in contact with the drilling rod has a strong tendency to break from the surface of the formation although it may still adhere to the drilling rod of the drill.

Keeping the marking fluid in contact with the wet solids mud results in the fluid permeating the permeable formation and establishes a gradient differential pressure from the well bore out of the drilling rod through the mud to the formation, which decreases the differential pressure that forces the drilling rod against the mud. By establishing this gradient pressure from the hole through the slurry to the formation, the penetration of the marking fluid by the cracked sludge is not limited to the penetration by that portion of sludge in which the shank of the punch was jammed. The fluid that permeates through the mud on each side of this portion can freely penetrate the formation and diffuse to a location behind the driller's stem, establishing a gradient pressure from the hole in the well through the mud to the formation. This gradient pressure substantially reduces the force with which the drilling rod is held against the mud by hydrostatic pressure in the hole. The dehydration and cracking of the mud, accompanied by the penetration of the marking fluid into the mud, also results in a change in friction between the mud and the drilling rod. As a result of some or all of these forces, the drilling rod loosens from the hole wall. After the marking fluid is placed in the permeable formation and, preferably, after said fluid has been maintained for a sufficient period for the fluid to cause the sludge to dehydrate or sink or crack and for the Fluid penetrates the mud, the tube can be worked by means of conventional mechanical methods, such as turns or vibrations, to help it detach it from the wall of the hole. It is not possible to estimate exactly the time that the marking fluid requires to sink, crack and penetrate the mud, but it can be from a few minutes to several hours, depending on the particular conditions of the well, the composition of the mud, its impermeability and other factors. Any suitable method can be used to place the marking fluid in the hole in the permeable formation. A preferred method for filling the hole in the permeable formation with the marking fluid of the present invention is to introduce a part of said fluid into a fluid circulation system of the well and to pump the fluid part, followed by the mud used in the Drilling of the well, downwards towards the drilling rod of the drill and upwards through the hole outside the drilling rod of the drill to the desired location and stop the flow when the fluid is in place. This way of placing fluids in particular tufts in a hole is well known to those skilled in the art. Without being limiting, it is believed that the aphrons present in the marking fluid seal the formation effectively after releasing the stuck tube or tool, to prevent the tube from subsequently binding. The following examples are presented to demonstrate the invention, but should not be considered as limiting the area of the invention. The surfactants evaluated that generate aphron, are the following: STEPOSOL ™ CA-207, a sulfate of ethereal alkyl ammonium that is 60% active; STEOL ™ CS-460, sodium laureth sulfate that is 60% active; and NEODOL ™ 25-3, a C12-C 15 alcohol 3EO athoxylate. The abbreviations used in the table or these specifications are the following: cp = centipoise; g = grams; bbl = 42 barrel of gallon; ppg = pounds per gallon; ppb = pounds per barrel; psi = pounds per square inch; fm = revolutions per minute; STI = slide thinning index which is the Brookfield viscosity portion of 0.5 fm and the Brookfield viscosity of 100 fm, a measure of the degree of slip slipping of a fluid; voi = volume.

Example 1 1.5 g of xanthan gum was hydrated in 175 g (0.5 bbl) of water. 0.5 g of surfactant that generates aphron (STEPOSOL ™ CA-207) was added when mixing in a 6-speed Hamilton Beach blender at the lowest speed. For this aphron-containing fluid, 91.5 g (0.3 bbl) of a mixture of 90 g of diesel fuel plus 1.5 g of oil-soluble surfactant (NEODOL ™ 25-3) was slowly added. This fluid containing oil-in-water aphron contains 1,875 ppb of xanthan gum, 0.625 ppb STEPOSOL ™ CA-207, and 1,875 ppb NEODOL ™ 25-3, in which the liquid phase contains 37.5 vol. % diesel fuel and 62.5 vol% water. Example 2 1.5 g of xanthan gum was hydrated in 175 g (0.5 bbi) of water. 1.0 g of a surfactant that generates aphron, STEOL ™ CS-460, was added when mixing in a 6-speed Hamilton Beach blender at the lowest speed. For this fluid containing aphron, 61 g (0.2 bbl) of a mixture of 60 g of diesel fuel and 1.0 g of NEODOL ™ 25-3 were added slowly. This fluid containing oil aphron in water contains 2.14 ppb of xanthan gum, 1.43 ppb STEOL ™ CS-460, and 1.43 ppb NEODOL ™ 25-3, in which the liquid phase contains 28.6 vol. % of diesel and 71.4 vol% of water. Example 3 300 g (1.0 bbl) of a mineral fuel of low viscosity was viscosified with 7.0 g of Cab-O Sil ™ M5 silica that releases gases. 6.0 g of NEODOL ™ 25-3 were added while mixing as in Example 1, followed by 88.5 g (0.25 bbl) of a mixture of 1.25 g of STEOL ™ CS-460 surfactant plus 87.25 g of water. The fluid is inverted to a viscous fluid of oil in water. 180 g are removed, which is designated as sample A. After 28 g (0.079 bbl) of a mixture containing 0.394 g of STEOL ™ CS-460 surfactant and 27606 g of water are added to lower the viscosity. This fluid containing oil aphron in water contains 5,025 ppb of fumed silica, 4.3 ppb of NEODOL ™ 25-3 surfactant, and 1.08 ppb of STEOL ™ CS-460 surfactant, in which the liquid phase contains 72.85 vol. % of fuel and 27.15 vol% of water. Example 4 174 g of sample A of example 3 are mixed with 102 g of a mixture of 1.44 g of STEOL ™ CS-460 surfactant in 100.56 g of water. Very fluid. 2.0 g of xanthan gum followed by 37 g of a mixture of 0.52 g of STEOL ™ CS-460 surfactant in 36.48 of water are added. This fluid containing oil aphron in water contains 3.09 ppb of xanthan gum, 3.25 silica fume gas, 2.79 ppb NEODOL ™ 25-3, and 1.14 ppb STEOL ™ CS-460, in which the liquid phase contains 68.7 vol. % of fuel and 31.3 vol% of water. Example 5 8.0 g of organophilic hectorite CARBO-GEL ™ is dispersed in 300 g (equivalent to 1 bbl) of diesel fuel with 1 g of propylene carbonate dispersant to form an all-viscous aqueous compound. 2.0 g of STEOL ™ CS-460, while mixing in a high speed blender. The aphrons were incoforated in the viscous fluid from the vortex in the mixer. Example 6 Example 5 is repeated, only 11.0 g of CARBO-GEL ™ are used. The fluids of Examples 1-6 were evaluated by the Brookfield viscosity at 0.5 fm, which is a measure of the LSRV, and the Brookfield viscosity at 100 fm. The viscosity portion of 0.5 fm at the viscosity of 100 fm is a measure of the slipping characteristics of fluid slides. The density of fluid coughs was also measured and used to calculate the concentration of aphrons in the fluids using the equation: (calculated density - current density) (100) + (calculated density). The data obtained appear in Table A. Table A Brookfield viscosity. co Density Density Vol. calculated from aprons example 0.5 fm 100 rpm STI ees EBS% 1 50,500 671 72 6.57 7.99 17.8 2 51,000 675 76 5.86 8.11 27.7 3 510,000 4550 112 6.85 7.71 11.1 4 230,000 4920 47 6.73 8.02 16.1 47,000 369 127 5.58 7.40 24.6 6 111,000 912 122 6.51 7.47 12.9 Example 7 A barrel equivalent (350 cubic centimeters) of an inverted fuel emulsion drilling fluid has 80/20 portion of diesel / water fuel and contains 5.5 ppb of CARBO-GEL ™ 1 ppb of propylene carbonate, 5 ppb of CARBO-TEC ™, 8 ppb CARBO-MUL ™, 3 ppb of silt, and 229 ppb of barite, in which the aqueous internal phase is 30% by weight of calcium chloride solution was placed in a Osterizer high-slip laboratory mixer and mixed for 5 minutes after adding 2 ppb of a fluorocarbon surfactant (non-ionic fluoroaliphatic polymeric esters). The density and viscosity are measured. This fluid, which contains almost 9.7% of aphrons, is passed through an APV Gaulin ™ homogenizer at 1000 psi and density and viscosity are again determined. The data obtained appear in Table B. Table B Fluid Viscosity Brookfield Density% 0.3 fm 0.5 fm 100 rpm STI Pfl Vol. Homoaeized No 23,000 15,200 215 71 11.43 9.7 Yes 74,000 48,200 490 98 11.52 7.5 EXAMPLE 8 The fluids having the composition of the fluids of Examples 1, 2, 3, 4, 5, 6, and 7 are used as a marking fluid to release a tube from a drilling machine stuck in a hole. A sufficient volume of fluid to cover the area where the tube jammed circulates through the drill tube to the location of the stuck tube. The circulation is stopped and the marking fluid is kept in the hole long enough for the fluid to release the clogged tube. From time to time, the tube moves by means of conventional mechanical methods, such as pulling it, to help release the tube.

Claims (9)

1. CHAPTER CLAIMING Having described the invention, it is considered as a novelty and, therefore, the content is claimed in the following:
2. CLAIMS 1. A marking fluid to be used when releasing stuck tubes or tools into a hole that is composed of a liquid selected from the group consisting of aqueous liquids, oleaginous liquids, and mixtures thereof, to which one or more viscosifiers are incoforated for the marking fluid to have a low slip velocity viscosity as measured with the Brookfield Viscometer at 0.5 fm of at least 10,000 centipoise, a surfactant that generates aphrons, and aphrons. 2. The marking fluid according to claim 1, wherein the density of the liquid and the concentration of aphrons is such that the marking fluid has the desired density.
3. 3. The marking fluid according to claim 1, which contains a continuous aqueous phase having a viscosifier.
4. 4. The marking fluid according to claim 1, which contains a continuous oil phase having a viscosifier.
5. 5. The marking fluid according to claim 2, which contains a continuous aqueous phase having a viscosifier.
6. 6. The marking fluid according to claim 2, which contains a continuous oil phase having a viscosifier.
7. 7. The marking fluid according to claims 1, 2, 3, 4, 5, or 6, wherein the low slip velocity viscosity is at least 40,000 centipoise.
8. 8. A method for releasing a stuck tube or tool into a hole consists of introducing the marking fluid of claim 1, 2, 3, 4, 5, or 6 to the depth of the point at which the tube was jammed. or the tool and in a volume sufficient to displace the fluid in the hole over the entire jammed area, and allow the marking fluid to soak for a sufficient period of time to release the stuck tube or tool. The method according to claim 8, wherein the marking fluid has a low slip velocity viscosity of at least 40,000 centipoise.