Offshore jacket platforms are designed to fulfil their intended purpose in oil and gas exploitation at designated service life periods. During the operational development, a number of field operators extend their platform service life if the reserves are still available. This technical paper proposes the method to assess the structural integrity of several aging platforms in a field with a simplified approach. Taking the case of “B” Field platforms installed in the mid-1990s, the detailed procedure and example are discussed thoroughly. Five indicators furnished with quantification procedures are also presented to propose the ranking methodology. This paper also proposes the method of jacket platforms grouping based on several similarity criteria. The results of this approach can be used as a baseline for more detailed structural integrity assessment for each group representation.

This paper briefly presents the investigation of risk based decision making for mobile mooring system. This paper used bow tie analysis to analyze the risk of mobile mooring failure. Bow tie analysis consists of FTA (Fault Tree Analysis) on left part and ETA (Event Tree Analysis) on the right part. FTA is useful to determine the potential causes from critical top event until the undesired events are obtained. ETA (Event Tree Analysis) is helpful to define the possible consequence by relating an initiating event to various consequence models. The investigation consists of determining the critical hazards of mooring system failure through investigating the root causes, the consequences, and the frequency index.

Kapal merupakan moda transpotasi untuk memindahkan penumpang atau barang dari satu tempat ke tempat lain melalui laut. Kapal dengan umur lebih dari 25 tahun secara umum tidak dapat dioperasikan lagi karena adanya Peraturan Menteri Perhubungan pada tahun 2005. Ketika umur kapal bertambah, maka kapal tersebut menjadi tidak efisien untuk dioperasikan. Scrapping kapal pada saat ini dianggap sebagai solusi terbaik kapal yang tidak beroperasi. Kegiatan Scrapping kapal meliputi persiapan peralatan dan pekerja, bersandarnya kapal, pemotongan dan pengiriman material hasil scrapping. Tujuan utama dari penelitian ini adalah menyusun skenario risiko dan menilai risiko yang ada pada industri scrapping kapal di Bangkalan Madura dengan metode Hazard and Operability Study (HAZOP). Metode HAZOP merupakan suatu cara identifikasi suatu risiko yang terjadi pada setiap pekerjaan dengan menggabungkan 2 kata penting yaitu parameter dan guideword menghasilkan penyimpangan (deviasi) hingga memberikan usulan tindakan pencegahan pada risiko kecelakaan. Analisis data dilakukan mulai mempersiapkan perlengkapan dan kondisi pekerja hingga pengiriman hasil scrapping. Metode berfungsi untuk mengetahui tingkat/level kecelakan pekerja dan dampak terhadap lingkungan di usaha scrapping kapal. Risiko terekstrim diperoleh oleh pembersihan sisa bahan bakar/oli dengan menggunakan sabun dengan nilai 19,32. Tindakan pencegahan meliputi Memperhatikan faktor-faktor keselamatan pada waktu perencanaan, pembangunan sistem keamanan, sistem keselamatan bagi pekerja ataupun lingkungan, hingga pengawasan atau pengecekan setiap pekerjaan, menyelidiki kerusakan yang terjadi pada kecelakaan dan memelihara kalender kejadian.

Recent years have shown the increasing number of SPAR offshore floating platforms built and delivered worldwide. This eventually is strongly related to the generic potential of such platforms, in term of economy and performance aspects, especially for the operation in deep water. For operation in harsh sea environment previous SPAR investigations suggested the addition of heave plate on its keel to enhance the heave motion quality. This paper reports an experimental study conducted on SPAR model, scaled 1: 125 from the full size, installed with a heave plate sized 1.3 of hull diameter. Results of the study demonstrate the additional of heave plate may reduce the heave reaction force due to wave excitation approximately 35% in comparison with that without heave plate. This in turn leads to the decreasing of heave response by as much as 54%. Evaluations suggest the reductions in heave reaction force and response are induced by the escalation of heave damping in the order of 49% generated by the heave plate. The experimental results are well verified by the outcomes of computations based on analytical method and strip theory.