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"Penerapan sistem proteksi korosi menjadi suatu keharusan terhadap konstruksi yang dibangun di daerah yang rawan korosi seperti dermaga (oil wharve) yang berada pada daerah pantai, guna pemeliharaan dan keselamatan khususnya terhadap kerugian akibat serangan korosi yang dari waktu ke waktu semakin besar. Penelitian yang dilakukan ini menitikberatkan pada evaluasi sistem proteksi korosi yang sudah ada pada oil wharves, dimana sistem proteksi yang sudah ada tidak mampu menahan korosi piles khususnya yang berada pada daerah splash dan pada sleeve. Untuk mendapatkan desain proteksi korosi yang optimal dilakukan mengukuran nilai pH air laut, kelarutan oksigen, mengamati kondisi T/R (transformer rectifier), kondisi coating dan pengukuran rapat arus air laut. Kemudian menghitung ulang kebutuhan anoda korban untuk sistem anoda korban, menghitung kebutuhan arus dan potensiaf rectifier untuk sistem arus tanding, dan menentukan alternatif jenis proteksi untuk diaplikasikan pada daerah splash yang mengalami korosi yang cukup tinggi. Tujuan penelitian ini adalah mengevaluasi dan mendesain ulang sistem proteksi korosi yang optimum untuk tiang-tiang pancang (piles) pelabuhan atau dermaga.Hasil penelitian menunjukkan adanya beberapa faktor yang menyebabkan proteksi korosi yang sudah ada tidak berjalan dengan baik, yaitu penggunaan clamp untuk menempelkan anoda korban pada pile, adanya aliran arus dan potensial yang terputus dari rectifier ke struktur, dan kondisi groundbed (menggunakan anoda grafit) yang diperuntukkan untuk melindungi struktur sudah tidak dapat memenuhi fungsinya secara maksimal (termakan usia). Dan penghitungan ulang kebutuhan anoda korban di dapatkan untuk Oil wharf # 1 & #2 membutuhkan 23.03 ton, Oil wharf # 3 membutuhkan 24.00 ton, Oil wharf # 4 membutuhkan 19.07 ton dan MD #1 - #10 membutuhkan 26.82 ton untuk jangka waktu 20 tahun. Anoda korban yang digunakan untuk proteksi katodik ini adalah Sapalum 111 (Galvanum Ill) yang merupakan jenis anoda paduan Aluminium-Zinc-Indium (AI-Zn-In). Pada Sistem proteksi arus tanding pada OW #3 menggunakan kebutuhan arus dan tegangan sesuai dengan desain hasil perhitungan yaitu, iTR =48.81 A , VTR = 19.18 volt dan sistem groundbed yang menggunakan anoda grafit digantikan dengan anoda MMO (mixed metal oxide). Untuk proteksi korosi pada daerah splash menggunakan petrolatum tape dan covering system.

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The implementation of corrosion protection system has become a requirement on the construction built in corroded environment as jetty (oil wharves) on the beach, for maintenance and safety especially on the effect of corrosion attacks, along its life is getting worst. Thesis done to analyze the evaluation of the corrosion protection system which has been installed on it for years, where the protection system can not longer cover the corrosion on piles, especially on the splash area and on sleeve. To gain the optimum corrosion protection design, we measuring the seawater pH, dissolved oxygen, observing T1R condition, coating condition and design current required for CP design. On the next step, we recalculation the need of anode for sacrificial anode system, to calculate the needs of current and potential rectifier for impress current system and then to design protection corrosion for splash area with the high corrosion environment.

The result appointed there is some factor causing corrosion protection installed did not work properly, which is the use of clamps to attach the sacrificial anode on piles and current and electricity potential being cut from TIR to structure, and groundbed condition (grafite anode) which is used to protect the structure, can not longer efficient as it was. Recalculation the needs of sacrificial anode on oil wharf #1 and #2 is 23.03 tons, oil wharf #3 need 24.00 tons, oil wharf #4 need 19.07 tons, and MD #1 to #10 need 26.82 tons for 20 years time. Sacrificial anode used on this cathodic protection is Sapalum Ill (Galvanum Ill), which is aluminum alloy (Al - Zn- In). The impress Current Protection system on OW #3 need current 6=48.81 A and volt Vt =19.18 Volt, based on the result of the calculation design, and replace the ground bed graphite anode with MMC, and using Petrolatum tape and covering system on he splash zone."

"Corrosion is a fundamental process which playsan important role in economics and safety.Apparently, corrosion cannot be avoided, but its severity can beprevented. Inhibitors have always been considered to be the first lineof defense against corrosion. Several corrosioninhibitors are available today. The objective of this study was toevaluate the effectiveness of sodium benzoate as an inhibitorto slow down or prevent corrosion. This project involves theuse of gravimetric measurements, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) to evaluate inhibitive action of sodium benzoate on corrosion behavior ofAA6063 aluminium alloy in seawater. The electrochemical measurements showed that the presence of sodium benzoate as an inhibitor significantly decrease the weight loss, corrosioncurrent densities (icorr), corrosion rates and double layer capacitance (Cd), whilst increasing the polarization resistance (Rp)."

"ABSTRAKPenelitian ini bertujuan untuk menganalisis pengaruh korosi atmosferlingkungan air laut terhadap disain ketebalan pipa penyalur. Dilakukan pengujianuji komposisi dan uji tarik untuk mengetahui indentifikasi pipa penyalur sesuaidengan API 5L grade B. kemudian dilakukan pengukuran ketebalan aktual pipauntuk mengetahui sisa umur pakai, dilakukan pengujian korosi dengan metodasalt spray dan pengujian lapangan berdasarkan data yang ada, mereview danmenganalisa data pipeline untuk mengetahui nilai risk tertinggi yang dijadikanasumsi dasar ketebalan pipa untuk daerah yang akan dijadikan tempat jalur pipapenyalur. Hasil kalkulasi, sisa umur berdasarkan ketebalan pipa API 5L grade Bdapat layak operasi. Dengan laju korosi 0.67 ipy maka ketebalan untuklingkungan air laut adalah 0.71 inci. dan hasil perhitungan risk tertinggi adalah4.02 maka ketebalan yang tepat adalah 0.51 inci. Dengan ketebalan jauh dariketebalan nominal maka dianjurkan pipa yang melewati laut atau bermalamhingga berhari-hari di dermaga atau pelabuhan perlu dilakukan Coating agar padasaat pemasangan tidak mengalami kemunduran disain.

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ABSTRACTThe main aim of this experiment is to analyze the influence of atmosphericcorrosion of sea water environment to the thickness design of the conduit. Testsperformed are the composition test and tensile test to determine the identificationconduit in accordance with API 5L grade B. Thereafter, the actual thickness ofthe pipe is measured to determine the remaining life, corrosion testing performedby the method of salt spray and field testing based on existing data. The pipelinedata are reviewed and analyzed to determine the highest risk to be the basicassumption thickness of the pipe to be used in the area of the supplier pipeline.The results of calculation of the pipeline remaining life based on the thickness ofthe API 5L grade B have a can reasonable operated. With the corrosion rate of0.67 (ipy) thickness for seawater environment is 0.71 inches and from the riskmanagement, highest risk calculation is 4.02 with the proper thickness is 0.51inches. With a thickness far from the nominal thickness of pipe, it is recommendedfor the pipes, that are distributed through the sea till stay up for days on the pieror port, to be coated so by the time of installation it will not experience a setbackdesign."

"Pipa baja API 5L Grade B merupakan jenis pipa yang banyak dipakai pada struktur anjungan untuk minyak bumi dan gas, dan umumnya banyak digunakan sebagai pipa penyalur gas, air, dan minyak. Instalasi sistem perpipaan dengan menggunakan pipa baja API 5L Grade B terutama di zona air laut perlu mendapatkan perhatian khusus karena instalasi sistem perpipaan pada zona ini rawan terhadap masalah korosi terutama di lingkungan air laut. Kandungan terbesar pada logam paduan API 5L Grade B adalah unsur besi (Fe) sebanyak 98,06 % berat sehingga paduan ini tergolong dalam kelompok baja carbon rendah. Dan komposisi utama penyebab korosi pada paduan baja API 5L Grade B ini sangat didominasi unsur  carbon (C), oksigen (O), dan unsur chlor (Cl) yang ada di zona air laut dengan produk korosi adalah fasa FeCl₂ (lawrencite), FeO₂ (lepidocrosite), Fe₂O₃ (hematite), dan Fe₃O₄ (magnetite). Laju korosi tertinggi diperoleh pada sampel API 5L Grade B yang diletakkan di dalam lingkungan pantai yaitu sebesar 20.84 mpy pada saat pasang, sedangkan laju korosi tertinggi pada saat surut terjadi pada sampel API 5L Grade B yaitu sebesar 12.14 mpy yang diletakkan di lingkungan air payau. Bentuk korosi yang terjadi meliputi tiga tahapan korosi, yaitu pada awalnya terjadi korosi seragam yaitu suatu bentuk korosi elektrokimia yang terjadi dengan tingkat ekuivalen tinggi pada seluruh bagian permukaan yang diuji dan sering kali meninggalkan suatu kerak dibalik permukaan atau endapan. Kemudian dengan meningkatnya laju korosi dan factor lingkungan korosi menyerang daerah celah, sehingga terbentuk korosi celah (crevice corrosion) dibatasi hanya untuk serangan terhadap paduan-paduan yang oksidanya terpasifkan oleh ion-ion agresif seperti klorida dalam celah-celah atau daerah-daerah permukaan logam yang tersembunyi dan pada akhirnya membentuk korosi sumuran (pitting corrosion).

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Steel pipe of API 5L Grade B is a type of pipe that is widely used in bridge structures for oil and gas, and generally widely used as gas, water, and oil pipelines. Installation of piping systems using steel pipe API 5L Grade B, especially in sea water zone needs special attention because of the installation of the piping system in this zone is prone to corrosion problems, especially in the marine environment. The content of the metal alloy largest API 5L Grade B is the element iron (Fe) around 98.06 wt% so that the alloy is classified in the group of low carbon steel. And the composition of the main causes of corrosion in steel alloys API 5L Grade B is dominated elements carbon (C), oxygen (O), and chlorine (Cl) in the zone of sea water with corrosion products are phases of FeCl₂ (lawrencite), FeO₂ (lepidocrosite), Fe₂O₃ (hematite) and Fe₃O₄ (magnetite). The highest corrosion rate was obtained on a sample of API 5L Grade B is placed in the beach environment is equal to 20.84 mpy at high tide, while the highest corrosion rate at low tide occurs in samples of API 5L Grade B is equal to 12:14 mpy placed in brackish water environments. Form of corrosion that occurs includes three stages of corrosion, the first is uniform corrosion namely a form of electrochemical corrosion that occurs with high equivalent level in all parts of the surface are tested and often leave behind a surface crust or sediment. Then by increasing the rate of corrosion and the environment factor, the corrosion attacked gap area, thus forming a crevice corrosion (crevice corrosion) which limited only to attacks on the oxide alloys by aggressive ions such as chloride in the gaps or areas of the metal surface hidden and eventually form the pitting corrosion (pitting corrosion)."

"Skripsi ini membahas perbedaan sebaran wilayah kesuburan perairan di Laut Jawa pada saat periode El Nino tahun 2006 dan periode normal tahun 2007. Analisis yang digunakan dalam penelitian ini adalah analisis deskriptif dengan cara interpretasi data citra satelit untuk melihat karakteristik sebaran suhu permukaan laut, konsentrasi klorofil-a dan arah arus permukaan laut yang selanjutnya dilakukan penampalan untuk mendapatkan sebaran wilayah kesuburan perairan. Hasil penelitian menunjukkan bahwa pada periode El Nino tahun 2006 sebaran suhu permukaan laut di wilayah penelitian lebih dingin, wilayah front termal lebih luas dan konsentrasi klorofil-a lebih tinggi dibandingkan dengan periode normal tahun 2007, sedangkan arah arus permukaan pada periode El Nino cenderung menjauhi sistem daratan dan periode normal lebih mengarah ke sistem daratan. Kesimpulan yang diperoleh yaitu wilayah kesuburan perairan periode El Nino memiliki cakupan lebih luas dibandingkan dengan periode normal.

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The focus of this study is different of rapid area distribution in Java sea on the El Nino and normal period. Analysis used of this study is descriptif analysis with interpretation citra satellite data to get distribution of sea surface temperature, clorofil-a concentration and sea surface current course, and than used overlay technique from GIS program. The result this research is distribution sea surface temperature more of cool, front thermal area and clorofil-a concentration more of wide on the El Nino period, and sea surface current course El Nino period is a faring of mainland system, but normal period is a nearing of mainland system. Conclution this research is rapid area on the El Nino period more of wide equalednormal period."

"The area of Riau Islands Province is approximately 251.810,71 km2 or 95,79 % of sea and 10.595.41 km2 or 4.21 % of land and there are 2.408 islands including big and small islands in the province. As we know that the small islands of Riau islands province directly face Singapore and Malaysia. These outer small islands has a function as the ocean security and defense zone. In this province the social structure that is not for the fishermen. The lack of their fish net/trap, the lack of their fund, the more polluted fishing area, and the irregular climate changes cause the fishermen difficult to fulfill their needs."

"Reinforced concrete structure are subjected to damage and deterioration during their service life because of exposure to many types of environmental influence. These damages or deterioration can reduce the performance and intended function of the structure. On several occasions structural failures are closely linked to the corrosion of steel reinforcement in concrete."

"Magnesium (Mg) alloys are receiving increasing attention due to their abundance, light weight, castability, formability, mechanical properties and corrosion performance. By selecting the appropriate combination of materials, coatings and surface modifications, their corrosion resistance can be greatly enhanced. Corrosion prevention of magnesium alloys is a comprehensive guide to the effective prevention of corrosion in these important light metals.Part one discusses alloying, inhibition and prevention strategies for magnesium alloys as well as corrosion and prevention principles. Part two reviews surface treatment and conversion. Beginning with an overview of surface cleaning and pre-conditioning, the book goes on to discuss the use of surface processing and alloying, laser treatments, chemical conversion and electrochemical anodization to improve the corrosion resistance of magnesium alloys. Coatings are then the focus of part three, including varied plating techniques, cold spray coatings, gel and electroless electrophoresis coatings. Finally, the book concludes in part four with a selection of case studies investigating the application of preventative techniques for both automotive and medical applications."