Evaluation of corrosion resistance of materials under conditions of moisture condensation in the presence of carbon dioxide

2020 ◽  
pp. 163-175 ◽  
Author(s):  
R. K. Vagapov ◽  
D. N. Zapevalov ◽  
K. A. Batullin
Keyword(s):  
Carbon Dioxide ◽  
Elevated Temperatures ◽  
Steel Corrosion ◽  
Corrosion Damage ◽  
Gas Production ◽  
Main Body ◽  
General Corrosion ◽  
Test Results ◽  
Corrosive Effect ◽  
Moisture Condensation

The paper investigates aspects of the development of corrosion processes under conditions of moisture condensation in the gas phase in the presence of carbon dioxide, which lead to the formation of local damage. The authors developed and tested a methodology for conducting steels corrosion testing The causes of the formation and the corrosive effect of moisture condensation on steel under conditions of carbon dioxide corrosion at gas production facilities are analyzed. It was found that at elevated temperatures, when the temperature difference is higher, more moisture condenses on the surface of the steel, which leads to an increase in the rate of both general and local corrosion by 2–3 times, compared to room temperature. The increased localization of corrosion processes under conditions of moisture condensation and the presence of CO2 makes the depth index of steel corrosion much higher than the general corrosion rate. When assessing the corrosiveness of environments with condensation of the aqueous phase, the rate of corrosion associated with the depth of the observed corrosion damage should be taken into account. According to the test results, it was determined that samples from the weld compared with the sample from the main body of the pipe differ in the degree of localization of corrosion in conditions of moisture condensation.

scholarly journals Corrosion resistance of steel for coiled tubing units

2021 ◽  
Vol 230 ◽  
pp. 01018
Author(s):  
Andriy Syrotyuk ◽  
Oleg Vytyaz ◽  
Rostyslav Leshchak ◽  
Jan Ziaja
Keyword(s):  
Steel Surface ◽  
Elevated Temperatures ◽  
Gravimetric Method ◽  
Corrosion Damage ◽  
Petroleum Products ◽  
Short Exposure ◽  
General Corrosion ◽  
Short Exposure Time ◽  
Barrier Films ◽  
Coiled Tubing

The gravimetric method was used to determine the corrosion rate of a pipe for coiled tubing. Scanning electron and optical microscopy were used to study the microstructure and to determine the nature of corrosion damages. It has been found that corrosion processes of different nature occurred in the studied systems “metal – environment”, in particular, in acid solutions, corrosion was caused by the of hydrochloric acid and the ambient temperature of 70°С. In solution with a smaller acid content, along with the general corrosion, there is a significant localization of the corrosion process (deep corrosion damage is formed: macro pitting and corrosion ulcers). The general corrosion was observed in the HCl solution (13 mass %), which destroys the pipe walls after 576 h of exposure. The neutral solutions caused the general corrosion of smaller intensity in comparison with the acidic environments, even taking into account the temperature factor. The surface-active substances or petroleum products that are present in the solutions, form barrier films on the steel surface, which prevent the access of corrosive components from the environment to the surface of the material, especially during the short exposure time. With the increase of the exposure at the elevated temperatures, the barrier films break down and the steel surface undergoes the general corrosion.

scholarly journals Media corrosiveness and materials resistance at presence of aggressive carbon dioxide

2021 ◽  
Vol 64 (11) ◽  
pp. 793-801
Author(s):  
R. R. Kantyukov ◽  
D. N. Zapevalov ◽  
R. K. Vagapov
Keyword(s):  
Carbon Dioxide ◽  
Oil And Gas ◽  
Gas Production ◽  
Carbon Dioxide Corrosion ◽  
Gas Field ◽  
Hydrocarbon Production ◽  
Field Development ◽  
Wide Range ◽  
Corrosive Effect ◽  
Equipment And Pipelines

At the present stage of gas field development, the products of many mining facilities have increased content of corrosive CO2 . The corrosive effect of CO2 on steel equipment and pipelines is determined by the conditions of its use. CO2 has a potentially wide range of usage at oil and gas facilities for solving technological problems (during production, transportation, storage, etc.). Simulation tests and analysis were carried out to assess the corrosion effect of CO2 on typical steels (carbon, low-alloy and alloyed) used at field facilities. Gas production facilities demonstrate several corrosion formation zones: lower part of the pipe (when moisture accumulates) and top of the pipe (in case of moisture condensation). The authors have analyzed the main factors influencing the intensity of carbon dioxide corrosion processes at hydrocarbon production with CO2 , its storage and use for various technological purposes. The main mechanism for development of carbon dioxide corrosion is presence/condensation of moisture, which triggers the corrosion process, including the formation of local defects (pits, etc.). X-ray diffraction was used for the analysis of corrosion products formed on the steel surface, which can have different protective characteristics depending on the phase state (amorphous or crystalline).

Estimation of corrosion aggression of aquatic media and corrosion resistance of steels of equipment of oil and gas condensate deposits

2021 ◽  
pp. 138-147
Author(s):  
A. R. Khafizov ◽  
◽  
V. V. Chebotarev ◽  
A. A. Mugatabarova ◽  
Keyword(s):  
Carbon Dioxide ◽  
Laboratory Tests ◽  
Oil And Gas ◽  
Elevated Temperatures ◽  
Metal Resistance ◽  
Gas Condensate ◽  
Carbon Dioxide Corrosion ◽  
Field Equipment ◽  
Moisture Condensation ◽  
Steel 20

Corrosion destruction of the metal of the field equipment and gas pipelines of the oil and gas condensate field (OGCF) was revealed, the cause of which is carbon dioxide corrosion. In order to determine the corrosiveness of the OGCF equipment media, laboratory tests were carried out with periodic moisture condensation in an atmosphere of carbon dioxide, autoclave tests in the liquid phase at elevated temperatures and partial pressure of CO2, and laboratory tests in the gas-vapor phase in the presence of CO2. Tests were carried out on steel 20, the selected solutions were tested on pipe segments of 09G2S steels (well connections and loops) and J55LT (tubing) of 2 types (old, after operation in a well, and new, not operated). Studies have shown that steels used at OGCF (steel 20, J55LT and 09G2S) are not resistant to carbon dioxide corrosion. All items of equipment made of these steels will be potentially weakly resistant to corrosion in the oil and gas condensate field. It is proposed to conduct tests of corrosion inhibitors from various manufacturers in laboratory and field conditions. Recommendations are given for the corrosion inhibitor selected according to the test results. Keywords: local corrosion; aggressiveness of the environment; metal resistance; well piping; plume; tubing; laboratory tests; autoclave tests.

Сравнение и интерпретация результатов обработки данных внутритрубной диагностики для условий транспортировки коррозионно-агрессивного газа

2021 ◽  
pp. 62-71
Author(s):  
Р.К. Вагапов
Keyword(s):  
Carbon Dioxide ◽  
Corrosion Damage ◽  
Gas Production ◽  
Operating Conditions ◽  
Corrosion Monitoring ◽  
Data Set ◽  
Internal Corrosion ◽  
Subsea Pipelines ◽  
Flux Leakage ◽  
Corrosion State

Many gas and gas condensate fields (Bovanenkovskoye, Urengoyskoye, Kirinskoye, etc.) are distinguished by the presence of corrosive carbon dioxide in the extracted products, which, in the presence of moisture, leads to the formation of local corrosion damage (pits, ulcers and their accumulations). One of the methods for monitoring the corrosion state of pipelines is in-line inspection (ILI), carried out by the magnetic flux leakage method. ILI is especially relevant for underground and subsea pipelines when the use of other methods of corrosion monitoring is limited or costly. Under conditions of gas production, in contrast to oil, corrosion can occur both along the lower generatrix of the pipe (bottom-of-line corrosion) and during condensation of moisture on the upper generatrix of the pipe (top-of-line corrosion). An important process is the correct planning of the ILI, the subsequent processing and interpretation of the obtained data set, which should be carried out taking into account the peculiarities of the development of carbon dioxide corrosion in the gas pipeline and in a comparative analysis with other data of corrosion control. When interpreting ILI data, one should take into account the mechanisms of corrosion development, operating conditions (route relief, etc.) and corrosion monitoring data obtained by other research methods (simulation tests, results obtained at other adjacent sections of pipelines, etc.). Correct and useful information according to ILI data will ensure reliable protection of gas pipelines and planning of measures to protect against internal corrosion.

Oxidation Inhibited Graphite: What Is It?

2017 ◽  
Author(s):  
Benjamin F. Hantz
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Service Life ◽  
Oxidation Resistance ◽  
Elevated Temperatures ◽  
Test Results ◽  
Sealing Material ◽  
Sealing Performance ◽  
Resistance To Oxidation ◽  
Industry Needs

When exposed to air at elevated temperatures, graphite oxidizes by a reaction between carbon and oxygen forming carbon monoxide and carbon dioxide. Using graphite as a sealing material and exposing it to the aforementioned environment, the reaction consumes graphite which degrades the sealing performance leading to leakage and seal unreliability. As a response to industry needs, graphite and sealing element manufacturers offer “oxidation inhibited” or more simply “inhibited” grades of graphite that show improved resistance to oxidation, however, there is no industry accepted definition that assures the purchaser that these grades of graphite do in fact have sufficient oxidation resistance for their specific application. This paper proposes a performance based definition for oxidation inhibited graphite and a protocol to convert test results to index any graphite resistance to oxidation. Furthermore, the paper provides a methodology to determine temperature limits and/or service life expectations for any graphite grade.

scholarly journals Top-of-line corrosion in the presence of carbon dioxide for gas production facilities

2021 ◽  
Vol 225 ◽  
pp. 01002
Author(s):  
Ruslan Vagapov
Keyword(s):  
Carbon Dioxide ◽  
Acetic Acid ◽  
Gas Phase ◽  
Hydrate Formation ◽  
Gas Production ◽  
Formation Temperature ◽  
Rate Of Development ◽  
Moisture Condensation ◽  
The Media ◽  
Determining Factor

Aspects of the development of corrosion processes under conditions of moisture condensation in the gas phase (top-of-line corrosion) in the presence of carbon dioxide, which lead to the formation of local damages, have been investigated. The influence of various factors on corrosion processes under conditions of moisture condensation (top-of-line corrosion) was studied: the acidity of the media (presence of acetic acid), the presence of alcohol (methanol is used in gas production as an inhibitor of hydrate formation), temperature, type of steel and the presence of a weld. In addition to the listed factors, the moisture content in the gas is the determining factor for the development of this type of corrosion under CO2 conditions. The rate of development of corrosion processes depends on the amount and composition of the liquid condensing on the metal surface. The rate of local carbon dioxide corrosion at top-of-line corrosion can reach several mm / year.

scholarly journals Mathematical simulation of the rate of carbon dioxide corrosion at the facilities of Gazprom dobycha Urengoy LLC

2019 ◽  
Vol 121 ◽  
pp. 01019
Author(s):  
Aleksandr Yusupov
Keyword(s):  
Carbon Dioxide ◽  
Oil And Gas ◽  
Corrosion Damage ◽  
Gas Production ◽  
Special Role ◽  
Carbon Dioxide Corrosion ◽  
Oil And Gas Production ◽  
Working Medium ◽  
Wide Range ◽  
Equipment Wear

In Gazprom dobycha Urengoy LLC, as in other oil-and-gas production enterprises, there are problems of increased equipment wear due to corrosion. A special role there plays CO2 corrosion. Despite the homogeneity of the extracted fluid and even chemical composition of the working medium, the nature and intensity of corrosion damage to pipelines and equipment varies over a wide range, due to different thermobaric parameters of well operation. To determine parameters influencing the rate of corrosion most different methods of statistical analysis were used. The paper provides a methodology for compiling a mathematical model and assessing its reliability. As a result, the equation of carbon dioxide corrosion in relation to the conditions of Achimov deposits of Urengoy oil, gas and condensate field was obtained. The type of the obtained equation was chosen according to the model of the classical de Waard-Milliams carbon dioxide corrosion equation. The model proposed by the authors describes the processes of carbon dioxide corrosion more reliably than the de Waard-Milliams equation does. The disadvantage of the developed model is that it does not reliably describe the speed of corrosion in wells with corrosion rates, significantly exceeding the average values for all wells studied.

Analysis of regulatory requirements for the assessment of carbon dioxide corrosion at gas production facilities

2021 ◽  
Vol 18 (2) ◽  
pp. 60-71 ◽  
Author(s):  
D. N. Zapevalov ◽  
R. K. Vagapov
Keyword(s):  
Carbon Dioxide ◽  
Corrosion Rate ◽  
Gas Production ◽  
Operating Conditions ◽  
Local Corrosion ◽  
Design Stage ◽  
General Corrosion ◽  
Carbon Dioxide Corrosion ◽  
Internal Corrosion ◽  
Production Facilities

Aim.In many fields, the produced gas contains corrosive CO2, which, in combination with moisture and other factors, stimulates the intensive development of corrosion processes, including local ones, which requires careful attention to the assessment of the corrosiveness of operating fluids in order to select effective anti-corrosion protection. Ensuring reliable and safe operation of equipment and pipelines prevents not only man-made risks, but also no less important environmental risks, which are especially dangerous for marine underwater facilities for Arctic coastal facilities.Methods.The analysis of normative and technical documentation in the field of assessment of corrosion risks, aggressive factors of internal corrosion and operating conditions of gas and gas condensate fields has been carried out.Results.One of the criteria for assessing the corrosion hazard is the corrosion rate of steel under operating conditions. However, the normative documents predominantly regulate the general corrosion rate, which evaluates the uniform thinning of the metal. But the rate of local corrosion is in no way taken into account, which is most relevant precisely for the conditions of carbon dioxide corrosion of steel. Another tool for identifying risks can be a corrosion allowance to the pipe wall thickness, which should be selected at the design stage and which is provided to compensate for corrosion losses during the operation of gas pipelines. It is shown that the minimum corrosion allowance (3 mm) specified in the main regulatory documents is insufficient, especially for offshore facilities.Conclusion.The experience of operating gas production facilities confirms that the rate of local corrosion can reach several mm/year. To limit this, effective anti-corrosion measures should be chosen, for example, the use of corrosion inhibitors, and a reasonable level of corrosion allowance should be provided that would take into account the corresponding level of corrosion risks at the gas production facility.

Aggressive environmental factors causing corrosion at gas production facilities in the presence of carbon dioxide

2020 ◽  
Vol 25 (4) ◽  
Keyword(s):  
Carbon Dioxide ◽  
Oil And Gas ◽  
Gas Production ◽  
Gas Condensate ◽  
Local Corrosion ◽  
Low Co2 ◽  
Partial Pressures ◽  
Moisture Condensation ◽  
Condensed Moisture ◽  
Gas Fields

The current stage in the development of promising gas and gas condensate fields in the Russian Federation is associated with facilities whose production includes carbon dioxide. Such objects include the Urengoyskoye oil and gas condensate field (Achimov deposits), the Bovanenkovskoye oil and gas condensate field, and the Kirinskoye gas and condensate field. The presence of CO2 in the produced gas, in combination with moisture condensation and a number of other factors, stimulates the intensive development of local corrosion processes. The main factors that influence the development of corrosion at infrastructure facilities and its localization in the presence of CO2 are considered. It is noted that when assessing the degree of aggressiveness of the environment, it is necessary to consider not only the CO2 content, but also other basic operating parameters that can affect corrosion. During the exploitation of gas fields, the conditions of moisture condensation that contribute to corrosion arise, which occurs when a temperature gradient arises and the produced gas is rapidly cooled. Higher temperatures increase both the amount of precipitated moisture and, accordingly, the rate of local corrosion. Simulation tests have shown that the development of local forms of corrosion (pitting, ulcers) are possible even at low CO2 partial pressures (from 0,025 MPa and above) in the presence of condensed moisture.

RMI BETA-C

Alloy Digest ◽  
1987 ◽  
Vol 36 (8) ◽  
Keyword(s):  
Carbon Dioxide ◽  
Tensile Strength ◽  
Base Alloy ◽  
Heat Treating ◽  
Production Equipment ◽  
General Corrosion ◽  
Aged Condition ◽  
Good Resistance ◽  
Solution Treated ◽  
Low Elastic Modulus

Abstract RMI Beta C is a heat-treatable titanium-base alloy that develops a tensile strength of over 200,000 psi in the solution-treated-and-aged condition. It has good ductility and toughness, good fabricability and a low elastic modulus. It has good resistance to general corrosion and it resists hot, aggressive environments containing ferric chloride, sodium chloride, carbon dioxide and hydrogen sulfide. Its applications include coil springs, fasteners, rivets and downhole oil-production equipment. This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ti-87. Producer or source: RMI Company.

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