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Kebutuhan energi nasional Indonesia terus meningkat seiring pertumbuhan ekonomi dan jumlah penduduk, sementara produksi minyak domestik hanya mampu memenuhi sekitar separuh dari total konsumsi harian yang melebihi 1,2 juta barel. Ketimpangan ini memaksa Indonesia untuk mengandalkan impor minyak, sehingga ketahanan energi nasional menjadi rentan. Salah satu strategi untuk mengatasi permasalahan ini adalah memperpanjang masa operasi infrastruktur migas yang sudah ada, termasuk anjungan lepas pantai. Penelitian ini melakukan analisis requalification terhadap struktur fixed wellhead platform berkaki empat di perairan dangkal kedalaman 100 kaki, dengan tujuan memastikan kelayakan teknis apabila masa operasional diperpanjang selama 20 tahun. Analisis mencakup empat aspek utama: in-place, seismic, fatigue, dan lifting. Pemodelan struktur dan pembebanan dilakukan menggunakan perangkat lunak Structural Analysis Computer System (SACS) berdasarkan data survei lapangan, laporan Asset Integrity Management, serta acuan desain dari API RP 2A WSD, AISC, dan DNV. Data metocean terkini digunakan untuk mendukung evaluasi. Hasil analisis in-place menunjukkan satu member dan satu joint mengalami overstress, sedangkan defleksi vertikal maupun horizontal memenuhi kriteria. Analisis seismic menghasilkan faktor beban gempa 0.443–0,448 untuk kondisi SLE dan 0,939–0,923 untuk DLE, dengan total 27 joint kritis; kapasitas aksial pile memenuhi kriteria. Analisis fatigue menunjukkan beberapa joint utama memiliki umur lelah kurang dari 63 tahun. Sebagai tindak lanjut terhadap overstressed joint pada kondisi in-place dan seismic SLE, dilakukan pembaharuan beban workover rig. Berdasarkan data terbaru, beban rig berkurang signifikan dari 213,87 kips menjadi 116,94 kips akibat menurunnya kapasitas produksi sumur. Setelah update beban, analisis in-place, seismic, dan fatigue kembali dilakukan, dengan hasil menunjukkan nilai UC memnuhi standar, serta peningkatan umur lelah pada beberapa joint sehingga kondisi struktur menjadi lebih aman. Pada analisis lifting, pengangkatan topside dilakukan dengan metode single hook point pada elevasi 28 m sehingga sudut sling terhadap bidang horizontal lebih dari 60°. Empat sling baja terhubung ke pilar deck utama, dengan hasil menunjukkan gaya maksimum pada sling sebesar 95.16 kips, member unity check maksimum 0,71, joint punching shear maksimum 0,22, dan seluruh nilai memenuhi kriteria API RP 2A. Pemilihan peralatan rigging meliputi sling 6×36 IWRC (diameter 60 mm, MBL 3040 kN), shackle Crosby G-2160 WLL 55 ton, serta padeye yang didesain khusus dengan material ASTM A36 dan las E-70, semuanya sesuai faktor keamanan yang disyaratkan. Rekomendasi perkuatan meliputi penambahan stiffener box pada member overstress, inspeksi rutin area rawan fatigue, serta perawatan marine growth. Kesimpulan akhir menyatakan bahwa struktur memenuhi kriteria kelayakan untuk perpanjangan umur layan 20 tahun dengan implementasi perkuatan dan inspeksi berkala, serta desain lifting dinyatakan aman tanpa memerlukan modifikasi tambahan. Kata Kunci: Requalification struktur, anjungan lepas pantai, wellhead platform, in-place analysis, seismic analysis, fatigue analysis, lifting, umur layan struktur, ketahanan energi. Indonesia’s national energy demand continues to increase in line with economic growth and population expansion, while domestic oil production is only able to meet approximately half of the total daily consumption exceeding 1.2 million barrels. This imbalance compels Indonesia to rely on oil imports, thereby rendering national energy security vulnerable. One strategy to address this challenge is to extend the service life of existing oil and gas infrastructure, including offshore platforms. This study conducts a requalification analysis of a fixed four-legged wellhead platform in shallow water at a depth of 100 feet, with the objective of assessing its technical feasibility for a 20-year service life extension. The analysis encompasses four main aspects: in-place, seismic, fatigue, and lifting. Structural modeling and load application were carried out using the Structural Analysis Computer System (SACS) software, based on field survey data, Asset Integrity Management reports, and design standards from API RP 2A WSD, AISC, and DNV. Updated metocean data were employed to support the evaluation. The in-place analysis revealed one overstressed member and one overstressed joint, although vertical and horizontal deflections satisfied the criteria. The seismic analysis yielded seismic load factors of 0.443–0.448 for the SLE condition and 0.939–0.923 for the DLE condition, with a total of 27 critical joints, while axial pile capacity remained adequate. The fatigue analysis indicated that several critical joints had fatigue lives of less than 63 years. As a follow-up to the overstressed joints under in-place and SLE seismic conditions, an update was applied to the workover rig loads. Based on the latest data, the rig load was significantly reduced from 213.87 kips to 116.94 kips due to declining well production capacity. After this adjustment, in-place, seismic, and fatigue analyses were repeated, yielding unity check values that met the standards and improved fatigue lives for several joints, thus enhancing the overall structural safety. In the lifting analysis, the topside was lifted using a single hook point method at an elevation of 28 m, resulting in sling angles greater than 60° relative to the horizontal plane. Four steel wire rope slings were connected to the main deck columns, with results showing a maximum sling force of 95.16 kips, a maximum member unity check of 0.71, and a maximum joint punching shear of 0.22—all satisfying API RP 2A criteria. Rigging equipment selection included 6×36 IWRC slings (60 mm diameter, MBL 3040 kN), Crosby G-2160 shackles (WLL 55 tons), and specially designed padeyes using ASTM A36 steel and E-70 welds, all of which complied with the required safety factors. Recommended strengthening measures include the addition of stiffener boxes on overstressed members, routine inspection of fatigue-prone areas, and marine growth maintenance. The overall conclusion is that the structure satisfies the technical requirements for a 20-year service life extension with the implementation of strengthening and periodic inspection, while the lifting design is deemed safe without requiring further modification.