scholarly journals Analisis Korosi Retak Tegangan pada Pipa Baja Karbon dalam Larutan Asam dan Sweet Gas

2018 ◽  
Vol 3 (1) ◽  
pp. 137
Author(s):  
Nendi Suhendi Syafei ◽  
Darmawan Hidayat ◽  
Bernard Y. Tumbelaka ◽  
Liu Kin Men

Pada eksplorasi di industri migas bahwa umumnya akan diikuti dengan zat korosif termasuk sweet gas (misalnya H2S dan CO2), maka akan mengakibatkan terjadinya peristiwa korosi. Bila terjadi peristiwa korosi retak tegangan akan mengakibatkan pipa baja karbon pecah sehingga berdampak produksi migas bisa terhenti. Penelitian ini bertujuan untuk menganalisis peristiwa korosi pipa baja karbon skala laboratorium dalam lingkungan asam dengan adanya sweet gas H2O dan CO2 dengan menggunakan metoda tiga titik pembebanan. Penelitian ini menggunakan bahan pipa baja karbon API 5L-X65 yang berada dalam lingkungan larutan asam asetat dan amoniak, kemudian diisikan sweet gas CO2 dan H2S dalam keadaan jenuh. Berdasarkan hasil uji mikrostruktur dan mikroskop terpolarisasi, terjadi peristiwa korosi retak tegangan, yaitu korosi retak tegangan transgranular dan korosi retak tegangan intergranular. Laju korosi yang terjadi pada sampel uji akan semakin besar, apabila defleksi yang diberikan semakin besar. Dalamnya retakan pada sampel uji akan semakin dalam apabila defleksi yang diberikan semakin besar. Laju korosi pada sampel uji akan semakin besar untuk defleksi yang sama tetapi variasi waktu paparan berbeda.Kata kunci: korosi, retak tegangan, pembebanan tiga titik, sweet gas, pipa baja karbon In industry exploration oil and gas that will generally be followed by corrosive substances including sweet gas (e.g H2S and CO2), then will result in corrosion event. If there is event a corrosion stress cracking will cause the pipe carbon steel to break so that production oil and gas can be stopped. This research aims to analyze the corrosion event of pipe carbon steel in laboratory scale on acid environment with the existence of sweet gas H2O and CO2 by using method three points loading. This research uses pipe carbon steel API 5L-X65 which is in the environment of acetic acid and ammonia solution, then filled with sweet gas CO2 and H2S in saturated state. Based on microstructure and microscope polarized test results, there is a phenomenon corrosion stress cracking, i.e corrosion stress cracking transgranular stress and corrosion stress cracking intergranular. The corrosion rate occurs in test sample test will be greater if deflection to given is greater. Inside crack in test sample test will deeper if deflection to given is greater. The corrosion rate in test sample test will be greater for the same deflection but variation of exposure time is different.Keywords: corrosion, stress cracking, three-point loading, sweet gas, pipe carbon steel

2018 ◽  
Vol 19 (2) ◽  
pp. 21-31 ◽  
Author(s):  
Nendi Suhendi Syafei ◽  
Darmawan Hidayat ◽  
Emilliano Emilliano ◽  
Liu Kin Men

The oil and gas industry exploration that will generally be followed by corrosive substances including sweet gas (eg H2S and CO2), it will result in corrosion event. The corrosion stress cracking will cause the carbon steel pipe to break so that production oil and gas can be stopped. The research aims in this paper is to analyze the corrosion event of carbon steel pipe in laboratory scale on acid environment with the existence of sweet gas H2O and CO2 by using three points loading method. This research uses carbon steel pipe API 5L-X65 which stay in condensation environment of 7700 ml aquades, 250 ml acetic acid and 50 ml ammonia, then filled sweet gas CO2 and H2S in saturated state. Based on the test results of microstructure and microscope polarized, there is a phenomenon corrosion stress cracking, i.e transgranular stress cracking corrosion and intergranular stress cracking corrosion. The accelerate corrosion that happened at the test sample will be greater if ever greater given deflection for the time of the same presentation. Crack deepness in the test of the test sample will deeper if ever greater given deflection. The cracks in the sample test will deeper if it was given stress σ greater for the same exposure time.


2019 ◽  
Vol 20 (2) ◽  
pp. 84-93
Author(s):  
Nendi Suhendi Syafei ◽  
S S Rizki ◽  
Suryaningsih Suryaningsih ◽  
Darmawan Hidayat

The oil and gas industry exploration that will generally be followed by corrosive substances including sweet gas (eg H2S and CO2), it will result in corrosion event. The corrosion stress cracking will cause the carbon steel pipe to break so that production oil and gas can be stopped. The research aims in this paper is to analyze the corrosion event of carbon steel pipe in laboratory scale on acid environment with the existence of sweet gas H2O and CO2 by using three points loading method. This research uses carbon steel pipe API 5L-X65 which stay in condensation environment of 1350 ml aquades, 150 ml acetic acid. Based on the figure (5.a) and figure (5.b) that the corrosion rate will increase with increasing exposure time, and the greater the stress that is given, the corrosion rate increases according to the image (6.a) and image (6.b). Whereas based on the results of microstructural tests using optical microscopes, pitting corrosion occurs, and corrosion events  occur are the stress corrosion cracking transgranular and intergranular based on figure 8.  


The formation/deposition of hydrate and scale in gas production and transportation pipeline has continue to be a major challenge in the oil and gas industry. Pipeline transport is one of the most efficient, reliable and safer means of transporting petroleum products from the well sites to either the refineries or to the final destinations. Acetic acid (HAc), is formed in the formation water which also present in oil and gas production and transportation processes. Acetic acid aids corrosion in pipelines and in turn aids the formation and deposition of scales which may eventually choke off flow. Most times, Monethylene Glycol (MEG) is added into the pipeline as an antifreeze and anticorrosion agent. Some laboratory experiments have shown that the MEG needs to be separated from unwanted substance such as HAc that are present in the formation water to avoid critical conditions in the pipeline. Internal pipeline corrosion slows and decreases the production of oil and gas when associated with free water and reacts with CO2 and organic acid by lowering the integrity of the pipe. In this study, the effect of Mono-Ethylene Glycol (MEG) and Acetic acid (HAc) on the corrosion rate of X-80 grade carbon steel in CO2 saturated brine were evaluated at 25oC and 80oC using 3.5% NaCl solution in a semi-circulation flow loop set up. Weight loss and electrochemical measurements using the linear polarization resistance (LPR) and electrochemical impedance spectroscope (EIS) were used in measuring the corrosion rate as a function of HAc and MEG concentrations. The results obtained so far shows an average corrosion rate increases from 0.5 to 1.8 mm/yr at 25oC, and from 1.2 to 3.5 mm/yr at 80oC in the presence of HAc. However, there are decrease in corrosion rate from 1.8 to 0.95 mm/yr and from 3.5 to 1.6mm/yr respectively at 25oC and 80oC on addition of 20% and 80% MEG concentrations to the solution. It is also noted that the charge transfer with the electrochemical measurements (EIS) results is the main corrosion controlling mechanism under the test conditions. The higher temperature led to faster film dissolution and higher corrosion rate in the presence of HAc. The EIS results also indicate that the charge transfer controlled behaviour was as a result of iron carbonate layer accelerated by the addition of different concentrations of MEG to the system. Key words: CO2 corrosion, Carbon steel, MEG, HAc, Inhibition, Environment.


Carbon steel is arguably one of the most efficient, reliable and safer kind of steel used in petroleum and gas industry for production, distribution and transmission of products. Acetic acid (HAc), is also one of the impurities in oil and gas during transportation from the well sites to the refineries. It is formed in the formation water, which also present in oil and gas production and transportation processes. Acetic acid aids corrosion in pipelines and as a result causes environmental degradation. It has been observed that high concentration of HAc increases the rate of corrosion of carbon steel in CO2 environment. Corrosion slows down production of oil and gas and thereby reduces revenue. In this work, a comparative study and analysis of carbon steel corrosion in the presence of HAc was carried out at 25oC and 80oC in CO2 saturated environment. Weight loss and surface analysis methods (XRD, EDX and SEM) were used to characterize the corrosion layers of the carbon steel samples at different conditions. The weight loss results show that the corrosion rate increased initially with the increase in the concentration of HAc and attained a maximum, and then gradually decreased. At 25oC with 500ppm of HAc, the corrosion rate is 1.35 mm/yr, and 1.80 mm/yr when 1000ppm of HAc was added to the solution. At 80oC and 500ppm HAc, the corrosion rate was 1.80 mm/yr and 2.70 mm/yr with 1000ppm of HAc. A further increase was observed at 3.45 mm/yr when 2500ppm of HAc was added to the system. This increase in corrosion rate is attributed to increase in temperature as increased temperature increases the rate of all reactions. The XRD analysis confirmed that the iron is formed in the absence of HAc while siderite (FeCO3), which is an ore of iron is observed on the materials with HAc. The SEM and EDX results confirmed that a fairly dense material of FeCO3 was formed in the absence of HAc and the layers became porous on addition of HAc to the solution. Key Words: Corrosion, Acetic acid, Carbon steel, CO2, Environment


2019 ◽  
Vol 20 (1) ◽  
pp. 86-99 ◽  
Author(s):  
Nendi Suhendi Syafei

Based on the results of the study that the test sample material using carbon steel pipe plate API 5L-X65 is in chamber. With the research using the three point loading method is the environment of CO2 gas and saturated H2S gas in a solution of 7900 ml of sea water and 100 ml ammonia, the corrosion phenomenon occurs. And the corrosion event that occurs, is stress corrosion cracking transgranular and intergranular based the results of microstructure test results and based the results of polarized microscopy test. The corrosion rate that occurs will increase with the deflection given to the larger test samples for the same exposure time, the corrosion rate that occurs will increase with the stress σ given to the test sample getting larger for the same exposure time and inside crack will get deeper with the deflection given to the test sample getting larger for the same exposure time.


Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5771
Author(s):  
Luis Manuel Quej-Ake ◽  
Jesús Noé Rivera-Olvera ◽  
Yureel del Rosario Domínguez-Aguilar ◽  
Itzel Ariadna Avelino-Jiménez ◽  
Vicente Garibay-Febles ◽  
...  

The review presented herein is regarding the stress corrosion cracking (SCC) phenomena of carbon steel pipelines affected by the corrosive electrolytes that comes from external (E) and internal (I) environments, as well as the susceptibility and tensile stress on the SCC. Some useful tools are presented including essential aspects for determining and describing the E-SCC and I-SCC in oil and gas pipelines. Therefore, this study aims to present a comprehensive and critical review of a brief experimental summary, and a comparison of physicochemical, mechanical, and electrochemical data affecting external and internal SCC in carbon steel pipelines exposed to corrosive media have been conducted. The SCC, hydrogen-induced cracking (HIC), hydrogen embrittlement, and sulfide stress cracking (SSC) are attributed to the pH, and to hydrogen becoming more corrosive by combining external and internal sources promoting cracking, such as sulfide compounds, acidic soils, acidic atmospheric compounds, hydrochloric acid, sulfuric acid, sodium hydroxide, organic acids (acetic acid, mainly), bacteria induced corrosion, cathodic polarization, among others. SCC growth is a reaction between the microstructural, chemical, and mechanical effects and it depends on the external and internal environmental sources promoting unpredictable cracks and fractures. In some cases, E-SCC could be initiated by hydrogen that comes from the over-voltage during the cathodic protection processes. I-SCC could be activated by over-operating pressure and temperature at flowing media during the production, gathering, storage and transportation of wet hydrocarbons through pipelines. The mechanical properties related to I-SCC were higher in comparison with those reviewed by E-SCC, suggesting that pipelines suffer more susceptibility to I-SCC. When a pipeline is designed, the internal fluid being transported (changes of environments) and the external environment concerning SCC should be considered. This review offers a good starting point for newcomers into the field, it is written as a tutorial, and covers a large number of basic standards in the area.


2019 ◽  
Vol 3 (1) ◽  
pp. 30-36
Author(s):  
Zuraini Din ◽  

In the oil and gas industry, pipeline is the major transportation medium to deliver the products. According to [1] containment of pipeline loss to indicate that corrosion has been found to be the most predominant cause for failures of buried metal pipes. MIC has been identified as one of the major causes of underground pipeline corrosion failure and Sulphate Reducing Bacteria (SRB) are the main reason causing MIC, by accelerating corrosion rate. The objectives of this study is to study the SRB growth, Desulfovibrio desulfuricans ATCC 7757 due to pH and determine the optimum value controlling the bacteria growth on the internal pipe of carbon steel grade API X70. The result shows that the optimum SRB growth is at range pH 5-5 to 6.5 and the exposure time of 7 to 14 days. At pH 6.5 the maximum corrosion rate is 1.056 mm/year. Corrosion phenomena on carbon steel in the study proven had influence by pH and time. From this result pitting corrosion strongly attack at carbon steel pipe. In the future project, it is recommended to study the effect of different pipe location for example the pipeline under seawater.


2015 ◽  
Vol 1123 ◽  
pp. 187-191 ◽  
Author(s):  
Atria Pradityana ◽  
Sulistijono ◽  
Abdullah Shahab

Inhibitor is generally known as one of many alternatives to control corrosion rate. These days, there is the rapid development in which finding inhibitor made from natural ingredient that is really eco-friendly. This research use type of sarang semut, Myrmecodia Pendans (MP), as bio inhibitor with concentrate level for about 0-500 mg/L and also using the material of carbon steel API 5L Grade B, and HCl 1 M as such corrosive media. The affectivity of bio inhibitor is generally known through such calibration which is called as Weight Loss, Potentiodynamic Polarization Test, Electrochemical Impedance Spectroscopy Test, and X-Ray Diffraction Test. The test results show that when it is added with bio inhibitor, there is the decreasing of corrosion rate from 109.88 mpy to 39.294 mpy in concentration level of 500 mg/L. Inhibition mechanism occurred is that there is the formation of a thin layer on the metal surface. Meanwhile, the XRD results show that there are compounds of Fe, FeCl3 and FeOCl in carbon steel API 5l Grade B.


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