Electronic Theses and Dissertation

Studi ini bertujuan untuk menganalisis kerusakan pipa bawah tanah yang terbuat dari Carbon Steel ASTM A333 Grade 6 akibat korosi dalam sistem perpipaan industri minyak dan gas. Pipa yang diteliti berfungsi mengalirkan fluida berupa kondensat dan air hasil produksi yang mengandung gas korosif seperti H2S dan CO2, sehingga dapat mengakibatkan penurunan kualitas material selama operasi. Masalah utama dalam penelitian ini adalah munculnya kegagalan pipa disebabkan oleh korosi yang dipengaruhi oleh kondisi lingkungan dan karakteristik material. Metode penelitian yang diterapkan mencakup pengujian kekerasan dengan metode Rockwell untuk mengidentifikasi sifat mekanik material, analisis mikrostruktur melalui pengujian metalografi, serta karakterisasi morfologi dan komposisi unusr menggunakan Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS). Di samping itu, dilakukan analisis X-Ray Diffraction (XRD) untuk mendeteksi fasa yang terbentuk akibat korosi, serta pengukuran pH tanah untuk untuk menilai dampak lingkungan terhadap kecepatan korosi. Hasil penelitian mengindikasikan bahwa kegagalan pipa disebabkan oleh mekanisme pitting corrosion yang muncul akibat terbentuknya area korosi lokal di permukaan material. Kondisi lingkungan yang bersifat korosif, terutama pH tanah yang rendah serta adanya gas H2S dan CO2, mempercepat reaksi elektrokima dan pembentukan produk korosi berupa oksida besi yang mengakibatkan penipisan dinding pipa secara lokal. Berdasarkan temuan tersebut, disimpulkan bahwa faktor lingkungan dan karakteristik bahan berperan signifikan dalam mempercepat kerusakan pipa, sehingga perlu ada langkah pencegahan seperti penerapan lapisan pelindung dan sistem proteksi katodik.

This study aims to analyze the failure of buried pipelines made of ASTM A333 Grade 6 carbon steel due to corrosion in an oil and gas industrial piping system. The investigated pipeline functions to transport condensate and produced water containing corrosive gases such as H₂S and CO₂, which may degrade the material properties during service. The primary issue addressed in this study is pipeline failure caused by corrosion influenced by environmental conditions and material characteristics. The research methods included Rockwell hardness testing to evaluate the mechanical properties of the material, metallographic examination to analyze the microstructure, and Scanning Electron Microscopy coupled with Energy Dispersive Spectroscopy (SEM-EDS) to characterize the surface morphology and elemental composition. In addition, X-ray Diffraction (XRD) analysis was performed to identify the phases formed as a result of corrosion, while soil pH measurements were conducted to evaluate the influence of the surrounding environment on the corrosion process. The results indicate that the pipeline failure was caused by a pitting corrosion mechanism resulting from localized corrosion on the material surface. Corrosive environmental conditions, particularly low soil pH and the presence of H₂S and CO₂ gases, accelerated the electrochemical reactions and promoted the formation of iron oxide corrosion products, leading to localized wall thinning of the pipeline. Based on these findings, it can be concluded that environmental factors and material characteristics play significant roles in accelerating pipeline deterioration. Therefore, preventive measures such as the application of protective coatings and cathodic protection systems are recommended to mitigate corrosion and extend the service life of buried pipelines.