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Hasil Pencarian

Ditemukan 3 dokumen yang sesuai dengan query
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Muhammad Adyutatama
""Analisa kegagalan pada water injection tubing dengan ukuran 1 7/8"" dan ketebalan 0.217"" (0,551 cm) dilakukan untuk menyelidiki penyebab kegagalan pada tubing tersebut dan untuk mencari material pengganti material tubing yang gagal tersebut. Sampel material water injection tubing digunakan.pada kondisi operas! down hole dibawah packer dengan temperatur operas! dan tekanan tubing produksinya adalah 264 _F dan 2627 psig. Kegagalan pada sampel disebabkan oleh korosi uniform yang meratayang disertai dengan korosi terlokalisasi. Jenis baja yang digunakan ditentukan dengan hasil pengujian komposisi, tank dan kekerasan yang dibandingkan dengan literatur. Pengaruh kenaikan temperatur terhadap kecepatan korosi diuji dengan pengujian polarisasi. Untuk pengaruh gas CO2 dan pemilihan material pengganti dilakukan dengan pengujian polarisasi menggunakan air injeksi dan air Nad 10000 ppm yang dilakukan pada temperatur 90 _C disertai dengan blowing CO2. Produk korosi diuji dengan EDX (Energy dispersive X-ray spectroscopy) dan XRD (X-ray diffraction). Pengujian lainnya yang dilakukan adalah pengujian resist ivitas dan pengujian komposisi air injeksi. Hasil pengujian menunjukan bahwa material sampel adalah baja API 5CT N80 dengan produk korosi Fe2O3, FeS, dan FeCO3. Penyebab korosi material tersebut adalah adanya komposisi CO2 pada water injection, temperatur operasi yang tinggi (264 _F). Jenis material pengganti tersebut adalah API 5 CT L80-9Cr, API 5CT L-80. dan API 5CT J55. Kecepatan korosi material tersebut menggunakan air injeksi dengan blowing CO2 adalah API 5 CT L80-9Cr (23.095 mpy), API 5CT L-80 (25.051 mpy). dan API 5CT J55 (70,879 mpy} sehingga material API 5 CT L80-9Cr digunakan sebagai material pengganti.""
Depok: Fakultas Teknik Universitas Indonesia, 2006
S41692
UI - Skripsi Membership  Universitas Indonesia Library
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Nuringtyas Rahwinarni
"[ABSTRAK
Korosi pada tubing baja karbon merupakan masalah serius bagi eksplorasi dan produksi minyak dan gas. Perilaku korosi baja paduan rendah 3%Cr (3Cr) dan baja karbon J55 dalam lingkungan air formasi diinvesitigasi dengan menggunakan pengujian tafel polarisasi potensiodinamik, electrochemical impedance spectroscopy (EIS) dan pengamatan metalografi. Komposisi dan morfologi dari produk korosi kedua baja dianalisa dengan energy dispersive spectroscopy (EDS) dan scanning electron microscopy (SEM). Hasil pengujian memperlihatkan adanya korosi lokal pada baja J55 dengan struktur mikro pro-eutektoit ferit dan perlit, dan tidak terlihat pada baja 3Cr dengan struktur mikro martensit temper dikarenakan terbentuknya lapisan produk korosi kaya-Cr yang padat, kontinyu dan melekat dengan baik ke permukaan baja. Lapisan produk korosi yang bercelah dan tidak kontinyu pada baja J55 menyediakan jalan bagi ion-ion agresif untuk masuk dan menimbulkan korosi lokal pada permukaan baja.
ABSTRACT
Corrosion of carbon steel tubings is a serious problem for oil and gas wet exploration and production. Corrosion behaviour of low bearing 3%Cr (3Cr) alloy steel and J55 carbon steel in produced water were investigated by polarisation potentiodynamic tafel, electrochemical impedance spectroscopy (EIS) and metallography observation. The composition and morphology of corrosion products were analyzed by energy dispersive spectroscopy (EDS) and scanning electron microscopy (SEM). The results show that there was localized corrosion was observed in J55 carbon steel with pro-eutectoid ferrite and pearlite microstructure, which did not exist in 3Cr steel with tempered martensite microstructure due to formation of a dense, continuous and adherent Cr-rich scale on surface steel. Many pits in the less adherent corrosion scale of J55 carbon steel could build up ion-diffusion channels which would degrade the protective capabilities of the product films and aggravate localized corrosion.
;Corrosion of carbon steel tubings is a serious problem for oil and gas wet exploration and production. Corrosion behaviour of low bearing 3%Cr (3Cr) alloy steel and J55 carbon steel in produced water were investigated by polarisation potentiodynamic tafel, electrochemical impedance spectroscopy (EIS) and metallography observation. The composition and morphology of corrosion products were analyzed by energy dispersive spectroscopy (EDS) and scanning electron microscopy (SEM). The results show that there was localized corrosion was observed in J55 carbon steel with pro-eutectoid ferrite and pearlite microstructure, which did not exist in 3Cr steel with tempered martensite microstructure due to formation of a dense, continuous and adherent Cr-rich scale on surface steel. Many pits in the less adherent corrosion scale of J55 carbon steel could build up ion-diffusion channels which would degrade the protective capabilities of the product films and aggravate localized corrosion.
;Corrosion of carbon steel tubings is a serious problem for oil and gas wet exploration and production. Corrosion behaviour of low bearing 3%Cr (3Cr) alloy steel and J55 carbon steel in produced water were investigated by polarisation potentiodynamic tafel, electrochemical impedance spectroscopy (EIS) and metallography observation. The composition and morphology of corrosion products were analyzed by energy dispersive spectroscopy (EDS) and scanning electron microscopy (SEM). The results show that there was localized corrosion was observed in J55 carbon steel with pro-eutectoid ferrite and pearlite microstructure, which did not exist in 3Cr steel with tempered martensite microstructure due to formation of a dense, continuous and adherent Cr-rich scale on surface steel. Many pits in the less adherent corrosion scale of J55 carbon steel could build up ion-diffusion channels which would degrade the protective capabilities of the product films and aggravate localized corrosion.
, Corrosion of carbon steel tubings is a serious problem for oil and gas wet exploration and production. Corrosion behaviour of low bearing 3%Cr (3Cr) alloy steel and J55 carbon steel in produced water were investigated by polarisation potentiodynamic tafel, electrochemical impedance spectroscopy (EIS) and metallography observation. The composition and morphology of corrosion products were analyzed by energy dispersive spectroscopy (EDS) and scanning electron microscopy (SEM). The results show that there was localized corrosion was observed in J55 carbon steel with pro-eutectoid ferrite and pearlite microstructure, which did not exist in 3Cr steel with tempered martensite microstructure due to formation of a dense, continuous and adherent Cr-rich scale on surface steel. Many pits in the less adherent corrosion scale of J55 carbon steel could build up ion-diffusion channels which would degrade the protective capabilities of the product films and aggravate localized corrosion.
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Fakultas Teknik Universitas Indonesia, 2016
S62103
UI - Skripsi Membership  Universitas Indonesia Library
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Azhar Maulana
"ABSTRAK
Coiled tubing merupakan jasa di bidang migas dalam perawatan sumur dengan tujuan meningkatkan produksi minyak gas bumi. Analisis kelayakan finansial proyek dibutuhkan sebagai hal terpenting dalam menentukan nilai ekonomis proyek. Net Present Value NPV merupakan salah satu parameter yang digunakan dalam analisis kelayakan proyek pada penelitian ini. Faktor penting pembentuk nilai NPV adalah tarif diskonto atau discount rate i yang dihitung konstan sampai masa pegembalian sumber modal, meskipun pada kenyataannya faktor yang mempengaruhi i setiap tahun tidak selalu sama, sehingga dibutuhkan pemodelan untuk mendekati nilai i yang tepat.Weighted Average Cost of Capital WACC digunakan sebagai metode dalam menghitung nilai i dengan menggabungkan ekuitas dan hutang sebagai struktur modal. Metode fuzzy digunakan untuk memperoleh nilai WACC yang tepat dari faktor pembentuk yang samar dengan menggunakan Triangular Fuzzy Number TFN . Periode proyek yang relatif pendek dengan nilai sumber modal yang tinggi merupakan risiko selanjutnya sehingga metode Risk Adjusted Discount Rate RADR digunakan untuk memperoleh nilai i yang sesuai. Dari pengolahan data, WACC memberikan nilai i 13.61 dan NPV sebesar Rp 964.215.293,88. Sedangkan fuzzy menghasilkan nilai i 13.53 dengan NPV Rp 979.733.959,80 serta RADR memberikan nilai i 16.00 dengan NPV Rp 520.191.241,50. Kata kunci: Analisis kelayakan, coiled tubing, Net Present Value NPV , discount rate, Weighted Average Cost of Capital WACC , Triangular Fuzzy Number TFN , Risk Adjusted Discount Rate RADR.

ABSTRACT
Coiled tubing is well intervention services in oil gas industry with objective to increase well production. The feasibility study is an important analysis to ensure economic value of the project. The author using Net Present Value NPV as one of feasibility factor which its value influenced by discount rate that calculated constant until return period of financial capital despite discount rate factor always change year by year then mathematic modeling required to determine discount rate precisely. Weighted average cost of capital WACC utilized as method to find the discount rate by considering value of company equity and cost of debt. Fuzzy method was chosen to accommodate uncertain of WACC rsquo s factors by using Triangular Fuzzy Number TFN . In other hand, the project require high financial capital cost with short project duration, so Risk adjusted discount rate RADR was used to determine appropriate discount rate. The value of each methods was calculated with result of WACC is 13.61 with NPV Rp 964.215.293,88. IDR, TFN is 13.53 and 979.733.959,80 IDR for NPV and RADR is 16.00 with amount of NPV is 520.191.241,50 IDR Keywords Feasibility study, coiled tubing, Net Present Value NPV , discount rate, weighted average cost of capital WACC , triangular fuzzy number TFN , risk adjusted discount rate RADR "
2017
T48091
UI - Tesis Membership  Universitas Indonesia Library