RU2669640C1 - Method of obtaining elastomer material for lining stator of screwdrive motor engine or screw pump - Google Patents

Abstract

FIELD: drilling of soil or rock.SUBSTANCE: invention relates to the production of an elastomeric material for drilling equipment and can be used in the manufacture of a stator cover of a screw downhole motor intended for drilling directional, deep, vertical, horizontal and other wells, drilling of sand plugs, cement bridges in oil and gas and oil and gas producing areas, and a screw pump designed for pumping liquids of various densities. Method for producing an elastomeric material for the lining of a stator of a screw downhole motor or a screw pump from a composition including butadiene-nitrile rubber, a sulfur-based curing group and vulcanization accelerators, a carbon black filler, zinc oxide, ester plasticizer, indene-coumarone resin, stearic acid, antioxidant, by mixing the components and vulcanizing the resulting mixture, characterized in that a combination of butadiene-nitrile rubber-BNR and hydrogenated butadiene-nitrile rubber – HBNR, where BNR with the content of nitrile acrylic acid – NAA from 33 to 40 wt. %, and HBNR with a degree of hydrogenation of 92–96 % and a content of NAA from 33 to 43 wt. %, in the ratio, mass. %: said BNR 60–90, said HBNR 10–40, and additionally further highly dispersed silicon oxide, phenol-formaldehyde resin, anti-scoring and processing additive, the stirring is carried out in two stages – firstly mix for 8–10 minutes in the mixer all the ingredients except for the curative group, at the temperature of the mixture at the end of mixing no more than 115–118 °C, then after cooling the mixture to 60–65 °C a vulcanizing group is introduced, mixed for 5–8 minutes at a mixture temperature at the end of mixing no more than 110 °C, the vulcanization is carried out at a pressure of 7.4 MPa at a temperature of 150 °C for 30 minutes, with the following ratio of components, mass. p: the indicated BNR – 60.0–90.0, indicated HBNR – 10.0–40.0, technical carbon – 50.0–85.0, highly dispersed silicon oxide – 5.0–10.0, oxide zinc – 3.0–7.0, antioxidants – 1.2–3.0, anti-scoring – 0.8–1.5, ester plasticizer – 5.0–13.0, phenol-formaldehyde resin – 10.0–25.0, indene-coumarone resin – 8.0–13.0, stearic acid – 0.5–1.2, curative group: sulfur – 1.8–2.8, vulcanization accelerators – 1.0–2.3, technological additive – 1.0–3.5.EFFECT: elastomeric material for drilling equipment with improved processing properties has been obtained.1 cl, 1 dwg, 2 tbl

Description

The invention relates to the production of an elastomeric material that can be used in the manufacture of a stator liner for a downhole motor (VZD) for drilling directional, deep, vertical, horizontal and other wells, drilling sand plugs, cement bridges in the oil and gas and oil and gas producing fields as well as a screw pump (HV), designed for pumping liquids of various degrees of viscosity. The VZD or VN is a volumetric rotary hydraulic mechanism that converts the pressure of the fluid pumped into the stator cavity (drilling fluid, formation or other fluid) into the rotational movement of the output shaft.

The main working parts of the VZD and VN are the stator and rotor ("working pair"). The stator is made in the form of a steel case, the rubber lining having helical teeth of the left direction is vulcanized to the inner surface of which. The steel rotor also has external helical teeth of the left direction, the number of which is one less than that of the stator. The rotor axis is offset relative to the stator axis by an eccentricity equal to half the height of the tooth. The teeth of the rotor and stator, being in continuous contact, form single working chambers closing at the length of the stator pitch. Drilling fluid entering the engine from the pumps can only go to the bit if the rotor of the engine rotates inside the stator shell, rolling around its teeth under the influence of unbalanced hydraulic forces. In this regard, cavities of high and low pressure are formed and the working process of movement is carried out. The design diagram (“working pair”) of the air-tightness and high-voltage devices is shown in Fig. one.

The operating conditions of such VZD and VN are extremely harsh - the impact of elevated temperatures during bottomhole (up to 200-210 ° C), high hydrostatic pressure (more than 60 MPa), aggressive well fluids (high oil, salt, low degree of purification of working fluids) with density up to 2000 kg / m ³ , including aerated solutions with sand content of 1-3% by weight, maximum particle size not more than 1 mm, the use of nitrogen-containing and acid-containing drilling fluids, pressure drop, high sliding speed (4-5 m / s) .

All of the above operational factors negatively affect the physicomechanical, dynamic, sorption properties and wear resistance of the rubber lining, which, as a result, leads to a decrease in energy characteristics and engine life, in critical cases - its complete failure. The most common materials due to their increased oil and gas resistance, good mechanical properties and high temperature resistance for stators are polymer compositions based on a copolymer of butadiene-1,3 and nitrile of acrylic acid (nitrile butadiene rubber) or hydrogenated nitrile butadiene rubber.

Known rubber mixture based on nitrile butadiene rubber, including nitrile butadiene rubber, a vulcanizing system based on sulfur with accelerators, fillers, including carbon black, zinc oxide, phenol formaldehyde resin, antioxidants, plasticizers (US 6905319).

Closest to the claimed is a method of obtaining an elastomeric material for drilling equipment, including for a stator for a downhole screw motor, from a composition comprising nitrile butadiene rubber, a sulfur-based vulcanizing system with accelerators, fillers, including carbon black, zinc oxide, phenol-formaldehyde resin, ester plasticizer, antioxidants, indene-coumarone resin, by mixing all components, pouring the rubber compound into the mold and vulcanization to obtain products of the required size (EP 1892416 A1). The disadvantages of this method are the low strength indicators and insufficient thermo-aggressive and wear resistance of the resulting vulcanizates. The technical result of the claimed method is to increase the elastic-strength, dynamic properties, thermal stability, abrasive wear resistance, fatigue resistance, resistance to aggressive working fluids, improve the technological properties of the elastomeric material for drilling equipment and increase the operating life and reliability of drilling equipment using it, in t .h. rubber-metal stators VZD and VN.

The achievement of the technical result is ensured by the fact that in the method for producing an elastomeric material for the stator lining of a downhole screw motor or a screw pump from a composition comprising nitrile butadiene rubber, a sulfur vulcanizing group and vulcanization accelerators, a filler is carbon black, zinc oxide, an ester plasticizer, an indene-coumarone resin, stearic acid, an antioxidant, by mixing the components and vulcanizing the resulting mixture, a combination of butadiene-nitrile is used Go rubber - BNK and hydrogenated nitrile butadiene rubber - GBNA, where the BNK contains nitrile of acrylic acid - NAC from 33 to 40 mass. %, and GBNK - with a degree of hydrogenation of 92-96% and the content of NAC from 33 to 43 mass. %, in the ratio, mass. %: the indicated BNA 60-90, the indicated GBNA 10-40, and additionally, finely divided silica, phenol-formaldehyde resin, anti-scorching and processing aid, mixing is carried out in two stages - first, all ingredients except the vulcanizing group are mixed for 8-10 minutes in a mixer , at a temperature of the mixture at the end of mixing no more than 115-118 ° C, then after cooling the mixture to 60-65 ° C, a vulcanizing group is introduced, stirred for 5-8 minutes at a temperature of the mixture at the end of mixing no more than 110 ° C, vulcanization is carried out under pressure 7.4 MPa at a temperature of 150 ° C for 30 minutes, in the following ratio of components, mass. hours:

Specified BNK - 60.0-90.0

Specified GBNK - 10.0-40.0

Carbon black - 50.0-85.0

Highly dispersed silica - 5.0-10.0

Zinc Oxide - 3.0-7.0

Antioxidants - 1.2-3.0

Anti-scoring - 0.8-1.5

Ester plasticizer - 5.0-13.0

Phenol formaldehyde resin - 10.0-25.0

Indene-Coumarone Resin - 8.0-13.0

Stearic acid - 0.5-1.2

Vulcanizing group:

Sulfur - 1.8-2.8

Vulcanization accelerators - 1.0-2.3

Technological additives - 1.0-3.5

According to the claimed invention, the rubber composition is used as a material for lining stators of downhole screw motors and screw pumps, applied to the inner surface of the stator by injection molding followed by vulcanization in open baths with polyethylene glycol as a heat carrier or vulcanization boilers.

A rubber-metal stator made using the developed method can be used in the oil and gas industry for drilling oil and gas wells in conditions of increased aggressiveness of the operating environment and an admissible bottom temperature of up to 135 ° C.

With an increase in the quantitative ratio of phenol-formaldehyde resin and carbon black indicated in the proposed recipe, rubber compounds are characterized by increased hardness, viscosity and are prone to vulcanization, which complicates their processing on technological equipment. At the same time, an increase in the concentration of ester plasticizer will lead to a decrease in the elastic strength properties, an increase in the rate of change in mass and volume when exposed to aggressive environments, and a decrease in the abrasion resistance of the rubber lining. A copolymer of butadiene-1,3 and nitrile of acrylic acid (NAC), butadiene-nitrile rubber (BNK) with a content of NAC of 33-40 mol. % With an increase in NAC content of more than 40%, strength characteristics, resistance to aliphatic hydrocarbons, oils, fuels, as well as resistance to heat aging increase, however, dynamic properties, frost resistance of rubbers are significantly worsened, and heat generation during repeated deformations increases. Examples of nitrile butadiene rubber with a NAC content of 33% to 40% used to create a rubber composition: Perbunan 3430F (NAC content 34 +/- 1%), Perbunan 3445F (NAC content 34 +/- 1%), Perbunan 3945F ( NAC content 39 +/- 1%) (Lanxess, Deutschland GmbH), Nipol DN3380 (NAC content 33%), Nipol 9025 (NAC content 35%) (Zeon Chemicals LP, USA), BNKS-40 AMN (NAC content 36- 40%) (OJSC Krasnoyarsk Plant SK, Russia).

Butadiene-nitrile rubbers have such disadvantages as low resistance to hydrogen sulfide, various additives and elevated temperatures, due to the high content of residual double bonds in rubbers of this type. In this regard, the rubber compounds are made on the basis of a combination of nitrile butadiene rubber with hydrogenated nitrile butadiene rubber with a hydrogenation degree of 92-96% and NAC content from 34% to 40%.

Examples of hydrogenated nitrile butadiene rubber with a NAC content of from 33% to 43 wt. % and the degree of hydrogenation of 92-96% used to create the rubber composition: Zetpol 2020 (NAC 36%, hydrogenation 92%), Zetpol 2010 (NAC 36%, 96% hydrogenation) (Zeon Chemicals), Therban C3467 ( the content of NAC 34 +/- 1%, the degree of hydrogenation 94.5%), Therban 3446 (the content of NAC 34%, the degree of hydrogenation 96%, Lanxess, Deutschland GmbH), Therban 4369 (the content of NAC 43%, the degree of hydrogenation 94.5% )

The study of the operating conditions and operating conditions of the VZD and VN stators showed that they work in extremely difficult conditions, therefore, to give the rubber lining increased fatigue resistance, abrasion resistance combined with high hardness, strength and elasticity, as well as high temperature resistance, aggressive resistance, and rubber fastening strength to the metal of the stator under conditions of exposure to high temperatures and steam, the proposed composition contains phenol-formaldehyde resin.

Examples of phenol-formaldehyde resins used to create the elastomeric material: S-1055, S-6700 (Qingdao Scienoc Chemicals Co., LTD, China), Ribetak R7515P, Ribetak 7529E (SI Group Ink., USA), Melres A (Melrob Group, United Kingdom) . To obtain a rubber mixture with improved dynamic and physico-mechanical properties, a “semi-effective” crosslinking system — sulfur vulcanization in the presence of accelerators — is used as the cure in the proposed elastomeric composition. Tetramethylthiuram disulfide (TMTD, Accelerator TMTD, Tiuram D) in combination with N-cyclohexyl-2-benzothiazol disulfide (Accelerator CBS, Sulfenamide C) is used as sulfur vulcanization accelerators, which provides a fairly wide vulcanization plateau and a high technological reliability of the rubber composition during processing vulcanizate, characterized by a set of cross-links of different polysulfide, determines high physical and mechanical properties and fairly good heat resistance. In order to increase the activity of accelerators, it is necessary to introduce vulcanization activators such as zinc oxide (Zinc White, BC-OM), as well as the use of stearic acid.

Due to the fact that the rubber mixture should have a sufficiently high hardness (75-80 Shore A units), wear resistance, strength while maintaining high elastic parameters, and should also be technologically advanced in the manufacture of products, a highly wear-resistant carbon black should be selected as a filler brand HAF N-339 in combination with carbon black medium activity brand SRF N-772. Another active filler according to the invention is highly dispersed silica (highly hydrated silicic acid, white soot). The use of white soot as a filler improves the heat resistance and oil resistance of rubber. The introduction of a bifunctional silane into the rubber mixture significantly increases the interaction of an inorganic filler (white soot) with an organic polymer (rubber), improving the mechanical properties of the latter, especially at elevated temperatures. It is also possible to use a precipitated silicic acid modified by vinylsilanes, while the additional use of silanes can be excluded. Examples of precipitated silicas used to create an elastomeric material: BS-100 (Soda OJSC, Russia), Ultrasil VN2, Coupsil VP 6508 (Degussa, Germany), Vulkasil C (Lanxess, Deutschland GmbH).

When products are used in an aggressive environment, the physical, chemical, and mechanical properties of rubber change. To protect the rubber lining of the VZD and VN from the destructive effect of oxygen, high temperatures and to prevent the processes of thermal and thermooxidative degradation, the use of antioxidants and anti-fatigue agents is necessary. The most effective rubber stabilizers based on nitrile butadiene rubber is 2-mercaptobenzimidazole (MBI, Vulkanox MB-2 / MG (Lanxess, Deutschland GmbH), a combination of 4,4-bis (1,1-dimethylbenzyl) diphenylamine (Alchem MBPA (Safic -Alcan, UK Limited), Naugard 455 (Chemtura Corp.) + 4 (5) -Metyl-2-Mercaptobenzimidazole zinc salt (ZMMB.I, Vulkanox ZMB-2 / C-5 (Lanxess, Deutschland GmbH), 2.2 , 4-trimethyl-1,2-dihydroquinoline polymerized (Acetonanil H, Vulkanox HS / LG (RheinChemie, Deutschland GmbH), Antioxidant TMQ), N-isopropyl-N'-phenyl-n-phenylenediamine (IPPD, Diafen FP, Santoflex IPPD (ChemPartners Orient, China.) Moreover, when using the San anti-skimmer system toflex IPPD + antioxidant Vulkanox ZMB-2 / C-5 has a synergistic effect.

To increase the ductility of the rubber mixture during preparation, processing and subsequent operation, as well as to reduce the viscosity and pour point, it is advisable to introduce ester plasticizers. It is recommended to use esters with high molecular weight, low volatility at high temperature and a tendency to extraction in working fluids as plasticizers for BNKs with medium-high NAC content. With an increase in concentration of more than 13 mass. hours there is sweating of the plasticizer on the surface of the rubber sheets, as well as the deterioration of the strength characteristics of rubber. Plasticizers of various chemical structures are possible: dioctyl sebacinate (DOS, molecular weight 430), three (2-ethylhexyl) trimellitate (TOTM, molecular weight 550), adipic acid polyester (Paraplex G-50, The HallStar Company, USA, molecular weight 6000).

The introduction of technological additives in the formulation of the rubber compound contributes to a more uniform dispersion of the fillers in the rubber matrix, lower viscosity and, therefore, improve the plastoelastic and rheological properties of the rubber compound. The best effect was achieved when anhydrous saturated fatty acid esters (Aflux 42, Aflux 54 (RheinChemie, Deutschland GmbH), Struktol WB222 (Struktol Company, USA) were used as technological additives, and mixtures of esters and zinc salts of fatty acids can also be used (Struktol WA 48 (Struktol Company, USA), Aktiplast T (RheinChemie, Deutchland GmbH).

The use of indeno-coumarone resins improves the workability of the mixtures, increases the stickiness, adhesion to the metal, and increases the tear and crack growth of vulcanizates.

Examples of grades of indeno-coumarone resins used to create an elastomeric material: ICS (China), Suprmix Cumar P-10, Suprmix Cumar P-25 (The HallStar Company, USA).

Due to the fact that the composition of the obtained material contains highly active carbon black, a semi-effective vulcanizing system (group) that increase the vulcanization rate, the risk of vulcanization of the rubber mixture during injection molding increases. To reduce the risk of premature vulcanization at the stage of processing the rubber mixture, especially in cases of manufacturing long stators, the filling of which can reach 30-40 minutes, add anti-scorching (retardation vulcanization). Examples of anti-scorchings: Vulkalent B / C, Vulkalent G, Vulkalent E / C (Lanxess, Deutschland GmbH), Santogard PVI (China). Examples of the invention.

Example 1

The content of components, mass. hours:

1. Nitrile butadiene rubber with a NAC content of 33% - 80.0

2. Hydrogenated nitrile butadiene rubber with a degree of hydrogenation of 96% and a NAC content of 34% - 20.0

3. Carbon black brand N-339 - 50.0

4. Carbon black brand N-772 - 15.0

5. Highly dispersed silica Vulkasil C - 10.0

6. Whitewash zinc BC-OM - 5.0

7. Stearic acid - 0.8

8. Paraplex G-50 ester plasticizer - 10.0

9. Antioxidant (Vulkanox ZMB-2 / C-5) - 1.0

10. Antifreeze (Santoflex IPPD) - 2.0

11. Phenol-formaldehyde resin Ribetak R7515P - 12.0

12. Indeno-coumarone resin Cumar R-25 - 5.0

13. Vulcanizing group (system):

Sulfur - 2.3

Accelerator TMTD - 0.8

Accelerator CBS - 1.3

14. Technological additive Struktol WB222 - 1,5

15. Anti-scorching Vulkalent B / C - 1.0.

The elastomeric composition was obtained under industrial conditions in a rubber mixer with Intermix rotors with a free chamber volume of 55 l together with rollers.

According to the invention, the rubber mixture was made in two stages. The process of mixing the masterbatch (stage I) in a rubber mixer with a free chamber working volume of 55 l, a chamber filling factor of 68% (45 kg) and rotor speeds of 35 rpm was carried out in the following sequence:

1. loading rubbers, their processing 30 sec;

2. loading of zinc oxide, stearic acid, Vulkanox ZMB-2 / C-2, Santoflex IPPD, Vulkalent B / C, Cumar P-25, Vulkasil C, stirring for 120 seconds;

3. the introduction of N-339, resin Ribetak R7515P, Struktol WB222, stirring for 100 seconds;

4. the introduction of N-772, plasticizer Paraplex G-50, stirring for 100 seconds;

5. lowering the plunger;

6. stirring for 120 seconds at a temperature at the end of mixing 105-110 ° C;

7. Unloading the masterbatch.

To exclude the vulcanization of the mixture, the introduction of a vulcanizing system (Sulfur, Accelerator CBS, Accelerator TMTD) was carried out in stage II on rollers after it was cooled to a temperature of 60-65 ° С. After the introduction of the ingredients was completed, the rolled rubber mixture was passed 5-6 times with the smallest possible thin gap between the rolls. Then, increasing the gap between the rollers, the mixture was released in the form of a tape of a given caliber. The temperature of the mixture at the end of mixing is not more than 110 ° C. The mixing cycle of stage I is 8-10 minutes, stage II is 8 minutes. Cooling tapes - water with a release agent.

Vulcanization of standard samples from the rubber mixture according to the invention was carried out on a hydraulic curing press with electric heating at a temperature of 150 ° C, a pressure of 7.4 MPa for 30 minutes.

Example 2

Given that rubber accelerators are allowed, and sometimes recommended, delayed action accelerators, if the temperature allows, to be introduced at the beginning of mixing, according to the invention it is possible in this case Accelerator CBS accelerator because the temperature allows (since the temperature during mixing at the first stage does not exceeds 120-123 ° C) to enter at the beginning of mixing for its best dispersion. Accelerator TMTD is an ultra-accelerator that can cause rubber vulcanization, so it was introduced into the second stage together with sulfur.

The content of components, mass. hours:

1. Nitrile butadiene rubber with a NAC content of 33% - 60.0

2. Hydrogenated nitrile butadiene rubber with a degree of hydrogenation of 96% and a NAC content of 36% - 40.0

3. Carbon black brand N-339 - 40.0

4. Carbon black brand N-772 - 25.0

5. Highly dispersed silica Vulkasil C - 8.0

6. Whitewash zinc BTs-0M - 5.0

7. Stearic acid - 1.0

8. TOTM ester plasticizer - 8.5

9. Antioxidant (Vulkanox ZMB-2 / C-5) - 1.0

10. Antifreeze (Santoflex IPPD) - 2.0

11. Phenol-formaldehyde resin Ribetak R7515P - 12.0

12. Indeno-coumarone resin Cumar R-25 - 5.0

13. Vulcanizing system: Sulfur - 2.0

Accelerator TMTD - 0.5

Accelerator CBS - 1.5

14. Technological additive Struktol WB222 - 1,5

15. Anti-scorching Vulkalent G - 0.8.

The elastomeric composition was obtained under industrial conditions in a rubber mixer with Intermix rotors with a free chamber volume of 55 l together with rollers.

According to the invention, the rubber mixture was made in two stages. The process of mixing the masterbatch (stage I) in a rubber mixer with a free chamber working volume of 55 l, a chamber filling factor of 68% (45 kg) and rotor speeds of 35 rpm was carried out in the following sequence, and one of the vulcanizing group accelerators was introduced into the first stage for its best dispersion in the masterbatch:

1. loading rubbers, their processing 60 sec;

2. loading of zinc oxide, stearic acid, Vulkanox ZMB-2 / C-2, Santoflex IPPD, Vulkalent G, Accelerator CBS, Cumar P-25, Vulkasil C, stirring for 120 seconds;

3. the introduction of N-339, resin Ribetak R7515P, Struktol WB222, stirring for 100 seconds;

4. the introduction of N-772, TOTM plasticizer, mixing for 100 seconds;

5. lowering the plunger;

6. stirring for 80 seconds at a temperature at the end of mixing 104-107 ° C;

7. Unloading the masterbatch.

The temperature of the masterbatch in the chamber of the rubber mixer is not more than 100-105 ° C. To exclude the vulcanization of the mixture, the introduction of vulcanizing agents (Sulfur, Accelerator TMTD) was carried out in stage II on rollers after it was cooled to a temperature of 60-65 ° C. After the introduction of the ingredients was completed, the rolled rubber mixture was passed 5-6 times with the smallest possible thin gap between the rolls. Then, increasing the gap between the rollers, the mixture was released in the form of a tape of a given caliber. The temperature of the mixture at the end of mixing is not more than 110 ° C. The mixing cycle of stage I is 8-10 minutes, stage II is 8 minutes. Cooling tapes - water with a release agent. Comparative technical characteristics of rubber compositions (standard samples):

The results of the production of vertical drilling stators (engine length 5400 mm, starting section of working bodies 7/8) using the developed elastomer (vulcanization conditions: temperature 150 ° C for 120 minutes):

Based on the results obtained, it can be argued that the developed method provides the best results in physicomechanical testing of the obtained material, a change in performance after exposure to high temperatures and aggressive media, as well as high adhesion of the material to the metal (even after exposure to high temperatures) and wear resistance, which allows use the material for the lining of rubber-metal stators with the provision of increasing the durability of VZD and VN when drilling in an aggressive well environment and downhole temperature to 135 ° C.

Claims (16)

A method for producing an elastomeric material for stator coating of a downhole motor or a screw pump from a composition comprising nitrile butadiene rubber, a sulfur vulcanizing group and vulcanization accelerators, a filler is carbon black, zinc oxide, an ester plasticizer, indene-coumarone resin, stearic acid, antioxidant, by mixing the components and vulcanizing the resulting mixture, characterized in that a combination of nitrile butadiene rubber - BNK and hydrogenated butadiene is used -nitrilnogo rubber - HNBR, NBR wherein the content of acrylonitrile - NAK from 33 to 40 wt. %, and GBNK with a degree of hydrogenation of 92-96% and the content of NAC from 33 to 43 mass. %, in the ratio, mass. %: the indicated BNA 60-90, the indicated GBNA 10-40, and additionally, finely divided silica, phenol-formaldehyde resin, anti-scorching and processing aid, mixing is carried out in two stages - first, all ingredients except the vulcanizing group are mixed for 8-10 minutes in a mixer , at a temperature of the mixture at the end of mixing no more than 115-118 ° C, then after cooling the mixture to 60-65 ° C, a vulcanizing group is introduced, stirred for 5-8 minutes at a temperature of the mixture at the end of mixing no more than 110 ° C, vulcanization is carried out under pressure 7.4 Pa at a temperature of 150 ° C for 30 minutes, at the following component ratio, wt. hours: The specified BNK - 60.0-90.0; The specified GBNA is 10.0-40.0; Carbon black - 50.0-85.0; Highly dispersed silicon oxide - 5.0-10.0; Zinc oxide - 3.0-7.0; Antioxidants - 1.2-3.0; Anti-scoring - 0.8-1.5; Ester plasticizer - 5.0-13.0; Phenol formaldehyde resin - 10.0-25.0; Indene-coumarone resin - 8.0-13.0; Stearic acid - 0.5-1.2; Vulcanizing group: Sulfur - 1.8-2.8; Vulcanization accelerators - 1.0-2.3; Technological additive - 1.0-3.5.

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