RU2178060C2 - Method of well casing - Google Patents

Abstract

FIELD: deep well drilling, particularly, methods of casing of oil-gas, geothermal, injection wells and other special wells, injection and producing wells on underground gas storage objects. SUBSTANCE: in method of well casing which includes successive injection to annular space of nonsolidifying isolating material with higher plugging and colmatage effect and solidifying plugging material forming solid rings with required strength characteristics fixing casing string, distance between fixing solid rings is determined by the following expression L =

, where E is pipe material modulus of elasticity, MPa; J is moment of inertia of casing string section, m⁴; Kk is coefficient considering influence of annular space nonsolidifying material on casing string stability; σ_cr is critical stress, MPa; F is cross-section area of casing string, sq. m. At temperature from 70 to 180 C nonsolidifying isolating material is used in the form of highly structurized gel-like suspension of thermopas and polygorskite clay with regulators of structural-mechanical, adhesive properties and density. Said material possesses high plugging ability and colmatage effect at the following amounts of components, mas. pts: water, 100; polygorskite clay, 5-17; thermopas, 5-15; chrysolite-asbestos, 6-15; granulated blast-furnace slag, 10-20; weighing compound, 20-120. At temperature from 150 to 300 C, nonsolidifying isolating material is used in the form of highly structurized neutralized slime of electroplating with regulators of structural-mechanical, adhesive properties and density. Said material possesses high plugging ability and colmatage effect at the following amounts of ingredients, mas. pts: water, 100; slime of electroplating (in terms of dry matter), 8-50; chrysolite-asbestos, 8-18; γ- belite-diatomaceous earth cement, 15-30; copper sulfate, 0.5-15; hematite, 10-120. At temperatures from 80 to 250 C, nonsolidifying isolating material is prepared from hydrocarbon-base fluid with regulator of structural-mechanical properties and density. Said material features high plugging ability and colmatage effect with the following amounts of components, mas. pts: diesel fuel, 100; bitumen, 1.5-12.5; cresol, 0.3-2.0; bentonite and powder, 10-30; rubber crumb, 10-20; barite, 20-120. EFFECT: increased service life and ecologic reliability of well casing under conditions of thermomechanical loads and deformation of casing string at temperatures from 70 to 300 C. 4 cl, 1 dwg, 1 tbl

Description

 The invention relates to well drilling, in particular to methods for attaching oil and gas, geothermal, injection, and other special wells (for example, injection and production wells at underground gas storage facilities (UGS)).

 A known method of securing wells by injection into the annular space of cement grout, hardening into cement stone [1].

 The main disadvantage of this method is the destruction of the cement ring in the process of crimping the casing after the time of the OZC and the perforation, subsequently leading to annular manifestations and interstitial flows.

 The above drawbacks lack the method of securing wells by pumping dispersed-reinforced grouting materials into the annular space [2].

 The disadvantage of this grouting material is the formation of a longitudinal gap between the casing and the cement ring when relieving internal pressure after crimping the string. In addition, the cement ring is susceptible to cracking and fracture by a drilling tool during well drilling and tripping operations.

 Rigid fastening of the casing string in the well also leads either to the destruction of the cement ring or to the breakdown of the casing pipes when alternating loads are applied to the casing string, such as starting or stopping high-temperature (geothermal) wells, injecting steam into the formation, etc. Violation of the integrity " rigid support is observed in injection and production wells drilled at underground gas storage facilities due to excessive fluctuations in gas pressures at different times of the year, as well as as a result of tectonic fluctuations of the earth's crust; subsidence of the earth's surface due to a decrease in reservoir pressure in the developed oil and gas fields (deposits).

 The closest technical solution to the proposed one is a method that includes the sequential injection of hardening grouting material with non-hardening. Non-hardening material is placed against impermeable formations. As a non-hardening material, a thermodynamically stable viscoelastic composition is used [3].

 The disadvantage of this method is that the viscoelastic composition obtained on the basis of polyacrylamide and a salt of trivalent chromium does not have sufficient insulating characteristics (plugging ability), it is easily eroded by formation water, moreover, due to this, it does not ensure the safety of the casing from the action of aggressive formation fluids and its stability in the barrel, in addition, the distance between the solid rings is chosen without regard to maintaining the stability and integrity of the casing.

The technical result of the proposed method is to increase the operational and environmental reliability and durability of the lining of wells under the action of thermomechanical loads and deformations of the casing at a temperature of from 70 to 300 ^o C.

где Е - модуль упругости материала труб, МПа;
J - момент инерции сечения обсадной колонны, м⁴;
K_k - коэффициент, учитывающий влияние заколонного нетвердеющего материала на устойчивость обсадной колонны;
σ_кр - критическое напряжение, МПа;
F - площадь поперечного сечения обсадной колонны, м².SUMMARY OF THE INVENTION: a method of securing a well, comprising sequentially injecting into the annulus a non-hardening insulating material with increased plugging ability and colding effect and a hardening cementing material forming solid rings with the necessary strength characteristics and fixing the casing, characterized in that the distance between the fixing solid rings is determined from the following expression:

where E is the modulus of elasticity of the pipe material, MPa;
J is the moment of inertia of the casing string, m ⁴ ;
K _k - coefficient taking into account the influence of annular non-hardening material on the stability of the casing;
σ _cr - critical stress, MPa;
F is the cross-sectional area of the casing, m ² .

 In cavernous and curved sections of the trunk, represented by sedimentary rocks, centering lights are installed.

 The distance between the solid rings is calculated based on the condition of maintaining the stability and integrity of the casing string in a non-hardening grouting material under the action of alternating thermomechanical stresses, for example, lengthening (shortening) of the casing string of a geothermal or steam injection well when starting (stopping), as well as linear deformation of the oil and gas production casing wells when creating excessive internal pressure in them at the time of crimping or perforation.

 As a material for creating solid rings, time-hardening binders are used based on traditional mineral grouting compositions (Portland cement, slag and other clinker-free cements), as well as composite organic materials and their mixtures with additional ingredients, depending on the technological and geological conditions of cementing.

 This method allows to increase the reliability and durability of the lining by creating cement rings with sufficient strength characteristics in the annular space around the casing at the design, technologically required intervals, and in the intervals between them a highly structured, gel-like, non-hardening insulation material with increased plugging ability and matting action.

 Non-hardening insulation material is prepared on an aqueous basis (fresh, mineral or organic salts) or non-aqueous basis (liquid hydrocarbons, high molecular weight alcohols or wastes containing these alcohols and salts) in the form of true solutions or structured with organic particles (peat, coal, bitumen, rubber , cellulose, algae, lignin) with polymer stabilizing reagents, as well as mineral particles (clay powders, natural, man-made and artificial, condensed carbonates and hydroxides, talc, asbestos, saprop al, mica, slag, lime and (or) waste containing these ingredients).

As a non-hardening insulation material at a temperature of from 70 to 180 ^o C use a highly structured gel-like suspension of thermal safety and palygorskite clay with regulators of structural-mechanical, adhesive properties and density, and this material has an increased tamping ability and colmatizing effect with its next composition, wt. hours:
Water - 100
Palygorskite clay - 5-17
Termopas - 5-15
Chrysotile Asbestos - 6-15
Granulated blast furnace slag - 10-20
Weighting compound - 20-100
The primary structure of the gel-like material is formed by dissolving the calculated amount of palygorskite clay in part of the water. In the remaining part of the water, in any mixing device at the drilling site (APPZ, clay mixer) or in Central Asia, the thermal hazard is dissolved and, without stopping mixing, chrysotile asbestos is added. Then the palygorskite and asbestos suspensions are pumped into the averaging tank and blast furnace slag and weighting agent are added sequentially with continued stirring. Stirring is continued until complete homogenization of the obtained visco-plastic, gel-like material. After determining the technological characteristics of the obtained material is pumped into the well by a known technology.

 The hardening of the structure of the gel-like material in the annulus occurs with continued hydration of the palygorskite clay at high temperature, as well as the formation of an additional spatial structure of chrysotile asbestos. In addition, chrysotile asbestos is a matting material and a good adhesive to casing and rocks.

An increase in the plugging ability, hardening of the gel structure and thermal stabilization of a highly concentrated suspension in the annular space are achieved by the thermal hazard. Termopas is a polymer of acrylamide, (meth-) acrylic acid and acrylonitrile in a ratio of 30-50; 10-30; 30-40 wt. hours, respectively, and heat-resistant up to 210-220 ^o C.

Further hardening of the gel structure in the annulus occurs with an increase in the alkalinity of the suspension due to the slow hydration (supply of OH ^- groups) of granulated blast furnace slag in the well at elevated temperatures.

 In addition, on the surface of asbestos, particles of hydroxides condense and chemisorption of the thermal hazard, thus eroding the boundary between the asbestos fibers and the thermal hazard solution with the formation of asbogel. Asbogel in this form can be qualified as a jelly or an elastic gel with thermodynamic stability.

 As regulators of the density of the gel-like material, barite, glandular and other weighting agents are used.

 The materials obtained according to this recipe possess the necessary technological parameters in the annulus - increased plugging ability, sufficient to create inter-layer isolation, and suffusion resistance in abnormally high reservoir conditions. In reservoir conditions, such a system turns into a non-hardening highly structured grouting material (VTM).

 The content of ingredients of non-hardening material is selected on the basis of laboratory studies and is regulated based on ensuring the required technological parameters during preparation, injection into the well and performing technological functions in the annulus.

 The concentration of palygorsk clay and chrysotile asbestos is selected based on the initial mobility of the solution (upper limit) and the formation of a sufficiently strong spatial structure to hold the weighting agent and the formation of TMV in the annular space (lower limit).

 The thermal safety content is normalized based on the achievement of the required filtration properties in the initial period (lower limit), as well as sufficient hardening of the spatial structure of the gel, which prevents suffusion destruction (upper limit).

 The content of blast furnace granulated slag is regulated on the basis of achieving the necessary environment for further hydration of palygorskite (lower limit) and maintaining the coagulation-thixotropic gel structure (upper limit) for a long time.

 The concentration of the weighting agent is selected based on the required density and rationing of sedimentation.

At temperatures from 150 to 300 ^o C as a non-hardening insulating material using highly structured neutralized sludge galvanic production (SHP) with regulators of structural-mechanical, adhesive properties and density, and this material has an increased tamping ability and colmatizing effect with its next composition, wt. hours:
Water - 100
SHGP (in terms of dry matter) - 8-50
Chrysotile Asbestos - 8-18
γ-BCC - 15-30
Copper sulfate - 0.5-15
Hematite - 10-120
SHG is a high-colloidal gel system with a density of 1025-1030 kg / m ³ , the dispersion medium of which is water, and the dispersed phase is the products of processing alkaline-salt solutions of electroplating baths of degreasing, phosphating, galvanizing, cadmium plating and oxidation, which are mainly represented by a complex of insoluble hydroxides zinc, chromium, cadmium, iron, copper and nickel.

 The high aggregative stability of SHP, apparently, is explained by a decrease in the surface tension of the solution due to the surface-active substances OP-7 and OP-10 present in it, coming from the etching and oxidation baths.

 After treatment of the saline solution with alkalis of monovalent metals and vacuum dehydration (these operations are also mandatory for the enterprise before the waste is discharged), SHP has a color from gray to dark brown, humidity up to 75%, has a static shear stress (SSS), and the resulting hydroxides of the above metals - high water holding capacity and thixotropy.

So, for example, SHP of 75% humidity has a SNA of _1/10 - 19/38 Pa, and 15 and 10% aqueous slurry suspensions have 4.8 / 6.2 and 1.8 / 2.9 Pa, respectively.

The SHG thixotropy coefficient is 2.1, and the dynamic shear stress is 46.8 Pa. Due to the high structural and mechanical properties SHGP has good retention of weighting agent and high sedimentation stability (not more than 0.5%) and low water loss (less than 6.5 cm ^3/30 min) due to the high water-holding capacity of polyvalent metal hydroxide gels. Water in metal hydroxides is in its two varieties - non-structural (in the form of Н ₂ О molecules) and structural (in the form of ОН ^- - groups).

 Additional regulation of the structural and mechanical properties (including plastic strength) of a highly structured, gel-like grouting material formed in the annulus is achieved by introducing chrysotile asbestos, previously treated in an aqueous solution of copper sulfate salt. During the interaction of polyvalent metal ions with surface asbestos groups, mineral fibers acquire high sorption activity. Under the influence of an acidic medium, asbestos fibers are split into elementary "needles" (fibrils), as a result of which the adhesive ability of cement material is also significantly increased.

After mixing of γ-BCC on the resulting acidic asbestos suspension, the active centers of the latter interact with Ca (OH) ₂ , which is released upon hydration of γ-BCC, forming a single and time-hardening mineral composition with high adhesive and deformation properties. As well as for the 1st formulation, asbestos is used according to GOST 12871-67 "Asbestos-chrysotile". The polyvalent metal salt (SPM) can be represented by sulfates, chlorides, nitrates of aluminum, iron, chromium, copper, manganese, zinc and other heavy metals, as well as combinations of two or more salts. Well-known industrial wastes containing mixtures of these salts are also used, for example, titanium chlorinator alloy waste (ORX), titanium chlorinator sublimates (VTX), manganese (II) nitrate waste (OMA), etc.

где Me⁺² - катион поливалентного металла;
γ-БКЦ - низкоактивное, бесклинкерное вяжущее, основным компонентом которого является минерал-двухкальциевый силикат, γ-модификации (γ-2CaO*SlO₂, γ-C₂S). Этот минерал является главной составной частью саморассыпающегося шлака (СРШ) - отхода производства рафинированного феррохрома, в котором содержание γ-C₂S достигает 78-80 %.Further hardening of the structure of highly plastic cement material in the annulus occurs due to new hydroxide gels of polyvalent metals formed during the exchange reaction between calcium hydroxide released during the hydration of γ-BCC and the salt according to the following reaction:

where Me ⁺² is a polyvalent metal cation;
γ-BCC - a low-activity, clinker-free binder, the main component of which is a mineral-dicalcium silicate, γ-modifications (γ-2CaO * SlO ₂ , γ-C ₂ S). This mineral is the main component of self-dissolving slag (SRS) - waste from the production of refined ferrochrome, in which the content of γ-C ₂ S reaches 78-80%.

 A mixture of SRS and quartz sand, obtained by disintegrator or other activation technologies, is called γ-BCC.

The advantage of γ-BCC over other low-activity slag binders is that its slow hydration begins in the annular space after exposure to temperatures above 85-90 ^o C, thereby ensuring the hardening of the structure only in the annular space and in technologically necessary time intervals.

приводит к образованию новых гелей гидроксида железа, которые являются кольматантами и способствуют дальнейшему упрочнению структуры ВГТМ в заколонном пространстве.The main purpose of hematite is to control the density of VGTM. However, the reaction between hematite and calcium hydroxide at high temperatures:

leads to the formation of new iron hydroxide gels, which are colmatants and contribute to further strengthening of the structure of VHTM in the annulus.

 The reaction of the formation of hydroxides is a continuous process due to the low activity of hematite and the slow release of calcium hydroxide during the hydration of low-activity γ-BCC, in connection with which the structure of VHTM is strengthened over time, its colding ability increases, and the coefficient of plugging ability increases.

 The content of sludge from galvanic production is regulated on the basis of ensuring initial sedimentation stability (lower limit), as well as the required initial mobility (upper limit). The content of chrysotile asbestos was also established on the basis of the necessary initial mobility (upper limit) and the achievement of the required rate of tamponing ability and sufficient strength of the structure of the HTM.

 When using copper sulfate with a concentration of less than 0.5%, a sufficient number of co-gels are not formed, and the rate of exchange reactions is low. When using a concentration of more than 15%, the effect does not increase.

 The content of γ-BCC is regulated based on the achievement of the coagulation-thixotropic structure of VHTM in the annulus depending on temperature conditions, as well as obtaining a sufficient amount of calcium hydroxide for exchange reactions with SPM of copper sulfate and hematite.

 When the content of γ-BCC is less than 15%, an insufficiently strong spatial structure is formed, and at concentrations of more than 30% the effect does not increase.

 Hematite concentration is also regulated on the basis of normalizing the density of VHTM and obtaining sedimentation-stable suspensions.

 The preparation of VGTM is as follows.

 The estimated amount of polyvalent metal salt (copper sulfate) or salt waste is introduced into the calculated amount of water, mixed until it is completely dissolved. Chrysotile asbestos is added to the resulting saline solution and stirring is continued until the asbestos completely dissolves (0.5-1.0 hours). After that, without stopping mixing, the calculated amount of SHP, γ-BCC and hematite are introduced sequentially until a homogeneous suspension is formed. Then, the calculated amount of the obtained material is pumped into the casing in the required sequence.

After drilling with the use of oil-based drilling mud (RNO) to fix the well at temperatures from 80 to 250 ^o C, a formulation of non-hardening insulating material is developed, hydrocarbon fluid with regulators of structural-mechanical, adhesive properties and density is used as the basis, and this material has an increased plugging ability and kolmatiruyuschee action in the next composition, wt. hours:
Diesel - 100
Bitumen - 1.5-12.5
Cresol - 0.3-2.0
Bentonite Clay Powder - 10-30
Rubber crumb - 10-20
Barite - 10-120
The technology for preparing the solution consists in the preliminary introduction of cresol into diesel fuel and, when circulating in CA in a closed system "measured capacity-pump-measured capacity", the calculated amount of bitumen, bentonite, crumb rubber and barite are successively added.

 Cresol is an aromatic diluent that increases the solubility in diesel fuel of the remaining ingredients, and also regulates the mobility of a highly viscous, gel-like solution.

 The concentration limits are set based on the achievement of a homogeneous stable system (upper limit) and the required mobility (lower limit).

 Bitumen is the primary hydrocarbon builder, increasing the viscosity of diesel fuel to the required values to hold the subsequent solid phase of bentonite clay powder.

 The concentration limits are set based on the conditions for creating a primary structure capable of retaining the solid phase (lower limit), as well as the inadmissibility of an excessive increase in viscosity, which affects the initial mobility (upper limit).

 A further increase in the structural and mechanical properties of the gel-like solution is achieved by bentonite clay powder. In the annular space, hardening of the structure occurs under the influence of temperature and contact of clay material with formation water. The content of bentonite is regulated on the basis of achieving satisfactory mobility and the required structural and mechanical properties of the gel-like paste in the annulus (upper limit), as well as achieving the primary structure of the solution capable of retaining the solid phase (lower limit).

 The content of rubber crumb is established empirically on the basis of the conditions for achieving the necessary mud properties of the cement slurry and geological conditions of cementing. The most effective concentrations were from 10 to 20 wt. h

 Barite is the most preferred dispersant weighting agent, capable of also affecting the structure-forming ability of the solution. The concentration of barite is selected based on the required density of the cement material.

 The drawing shows a diagram of a method of fixing a well in a sedimentary complex of rocks with a productive gas reservoir. As can be seen from the drawing, a solid cement ring 1 is installed in the zone of the productive formation 2. Subsequent solid cement rings are installed at distances calculated according to the above expression. In the spaces between the cement rings, non-hardening cement material is pumped 3. Centering lights 4 are installed in the cavernous areas.

 Thus, the above information indicates that the proposed technical solution meets the criteria of "novelty" and "significant difference". In addition, the disposal of the aforementioned industrial waste will solve an equally important environmental problem.

 The use of this technical solution creates a positive effect in relation to the known technical solutions, which is confirmed by the results of comparative tests (see table).

 As can be seen from the table, the proposed non-hardening grouting materials on a water and hydrocarbon basis differ from the known (prototype) significantly better technological parameters, a wide range of regulation of density and spreadability and higher heat resistance, as well as increased values of the coefficients of plugging ability, adhesion to the surrounding medium. In determining the comparative colmatizing ability, the value of a known technical solution (prototype) was taken as a unit.

 The method of fastening a well according to the proposed technical solution is as follows.

 Example. It is required to fasten a high-temperature geothermal well with a depth of 4001 m drilled in igneous rocks and intended to be used as an object for creating a hydro-circulation geothermal system (the project was carried out by the Federal State Unitary Enterprise Scientific and Production Center "Nedra" in the North Caucasus).

The density of the drilling fluid in the well is 1120-1150 kg / m ³ , the temperature at the bottom is 223 ^o C.

 The stratigraphic section of the well is represented by stable granitoids and Eljurti granites. Nominal diameter of the well - 215.9, average cavernosity coefficient - 1.1; permeable tectonic cracks along the trunk are absent. The diameter of the casing string is 139.7 mm, the steel grade is S-95, and the wall thickness is 9.2 mm. Permissible internal pressure for casing pipes is 75.2 MPa, permissible tensile load is 2070 kN.

When conducting hydraulic fracturing of rocks (R _g.raz • 65-70 MPa), injection of cold water and production of superheated steam, in the case of continuous cementing from the bottom to the mouth, thermomechanical stresses arise in the wellhead, exceeding the permissible values for both cement stone and casing, which leads to the destruction of the cement sheath and casing.

For example, the calculations show that when producing superheated steam, the temperature of which at the wellhead is 140-160 ^o C or more, tensile loads of 3700-4500 kN occur in the upper part of the casing string. Obviously, such loads will inevitably lead to the destruction of the "rigid" well support. Stress can be prevented if the sections of the casing are not fixed rigidly, but have the possibility of longitudinal and transverse movement (deformation) between the cement rings, i.e., within the part of the column located in a non-hardening grouting material.

The distances between the fixing solid cement rings, for example, for the case of a production well at a temperature of the produced steam-water mixture of 140-160 ^o With calculated based on the above expression and they are 270-350 m

As the first portion of the grouting material, a hardening grouting mortar based on γ-BCC with setting regulators is pumped into the well, which has the following technological characteristics:
Water-cement ratio - 0.5
Density, kg / m ³ - 1820
Spreadability, cm - 17-18
Thickening time at 200 ^o С, min - 320
Water separation,% - 0.2
The coefficient of plugging ability, K _t - 1.95.

The tensile strength of cement stone at T = 223 ^o C after 2 days, MPa, bending - 5.8, compression - 18.9.

As a second portion, a highly structured non-hardening grouting material based on SHP is pumped with the following ingredients (parts by weight):
SHGP (in terms of dry matter) - 50
Water - 100
Chrysotile Asbestos - 17.0
γ-BCC - 17.0
Copper sulfate - 5.0
Hematite - 110.0
Before injection into the well, the prepared solution has the following technological parameters:
Density, kg / cm ³ - 1650
Spreadability, cm - 16.0-16.5
Water separation,% - 0
The coefficient of plugging ability, K _t - 1,75
After testing in an autoclave for 5 hours at T = 223 ^o C and P = 50 MPa, the resulting structured non-hardening grouting material acquires the following parameters:
Density, kg / m ³ - 1650
Spreadability, cm - does not flow (plastic material)
Water separation,% - 0
The coefficient of plugging ability, K _t - 2.5
Plastic strength, MPa - 0.9-1.3
Adhesion to the rock, MPa - 0.5-0.7
Clutch with casing, MPa - 0.2-2.5
Subsequently, the operation is repeated by pumping grouting mortar and non-hardening composition in the required calculated quantities in sequence.

Sources of information:
1. Bulatov A. I. The formation and operation of cement stone in the well M., Nedra, 1990.

 2. Dispersion-reinforced grouting materials E. S. Tangalychev, B. C. Bashkutov, O. K. Angelopulo et al. M., NIIOENG, ser. "Drilling" issue. 19 (81), 1984.

 3. Patent of the Russian Federation 1301961. Priority dated 11/05/83, Publ. in bull. from 04/07/87.

Claims (2)

1. A method of securing a well, comprising sequentially injecting into the annular space a non-hardening insulating material with increased plugging ability and colding effect and a hardening cementing material forming solid rings with the necessary strength characteristics, fixing the casing, characterized in that the distance between the fixing solid rings is determined from the following expression:

where E is the modulus of elasticity of the pipe material, MPa;
J is the moment of inertia of the casing string, m ⁴ ;
K _to - coefficient taking into account the influence of annular non-hardening material on the stability of the casing;
σ _cr - critical stress, MPa;
F is the cross-sectional area of the casing, m ² . 2. The method according to p. 1, characterized in that at temperatures from 70 to 180 ^o C as a non-hardening insulating material using a highly structured gel-like suspension of thermal safety and palygorskite clay with regulators of structural-mechanical, adhesive properties and density, and this material has a high tamping ability and kolmatiruyuschee action in its next composition, wt. hours:
Water - 100
Palygorskite clay - 5-17
Termopas - 5-15
Chrysotile Asbestos - 6-15
Granulated blast furnace slag - 10-20
Weighting compound - 20-120
3. The method according to p. 1, characterized in that at temperatures from 150 to 300 ^o C as a non-hardening insulating material using a highly structured neutralized sludge galvanic production - SHPG with regulators of structural-mechanical, adhesive properties and density, and this material has increased tamping ability and kolmatiruyuschee action in its next composition, wt. hours:
Water - 100
ShPG (in terms of dry matter) - 8-50
Chrysotile Asbestos - 8-18
γ-BCC - 15-30
Copper sulfate - 0.5-15
Hematite - 10-120
4. The method according to p. 1, characterized in that at temperatures from 80 to 250 ^o With for the preparation of non-hardening insulating material as the basis use a hydrocarbon liquid with regulators of structural and mechanical properties and density, and this material has an increased tamping ability and colmatizing effect in the following composition, wt. hours:
Diesel - 100
Bitumen - 1.5-12.5
Cresol - 0.3-2.0
Bentonite Clay Powder - 10-30
Rubber crumb - 10-20
Barite - 20-120

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