ANALISA KERUSAKAN PIPA DUCTING SCRUBBING BERBAHAN CARBON STEEL SS400 DI PABRIK PUPUK NPK-1 PT PUSRI PALEMBANG

The purpose of this research was to discover the various reasons of failures and appropriate repair options for the line ducting cleaning unit system at PT Pusri Palembang's NPK-1 production facility. The main cause of the failures was determined to be a deterioration of the ducting line material caused by corrosion on the inner side of the ducting pipe composed of SS400 carbon steel. We made investigation including an analysis of the thickness of the damaged ducting pipe, as well as a visual check. The investigation showed that the corrosion caused an average drop in pipe wall thickness of up to 70%. The fixed load superimposed on the ducting pipe and the carrying capacity of the piping affect ducting strength, but corrosion on the inner surface of the pipe, caused by direct contact with corrosive and hygroscopic process dust, reduces ducting wall strength against axial and lateral loads. A Failure pipe caused losses and unscheduled shutdowns of production process, will be increased the repair costs and increases the risk of human accidents. The suggestion of investigation results is to upgrade the ducting pipe materials to knowed corrosion-resistant materials, such as stainless-steel grade SS304. Also, should be taken is also regularly to inspect the ducting cleanness for the internal of ducting and control the dust flow rate through the scrubbing system. As conclusion, the suggestions given are to mitigate the risk of corrosion impact by maintaini­­­­­­ng ducting strength within the minimizing ducting system failures and ensuring the NPK plant's operation reliability.Penelitian ini menganalisis kerusakan pada line ducting scrubbing sistem unit di pabrik NPK-1 PT Pusri Palembang dan bertujuan untuk menentukan penyebab utama kegagalan dan mengidentifikasi solusi perbaikan yang tepat. Penyebab utama kegagalan ini disimpulkan sebagai penurunan kekuatan ducting line akibat korosi pada sisi dalam pipa ducting yang terbuat dari carbon steel SS400. Dalam penelitian ini, dilakukan kajian terhadap design awal material ducting, pemeriksaan ketebalan pipa ducting yang rusak, serta pemeriksaan visual. Hasilnya menunjukkan pengurangan ketebalan dinding pipa rata-rata hingga 70% akibat korosi. Kekuatan ducting dipengaruhi beban tetap yang ditumpangkan pada pipa ducting dan daya dukung oleh perpipaan, namun korosi pada permukaan sisi dalam pipa yang bersentuhan langsung dengan debu proses korosif dan higroskopis menyebabkan penurunan kekuatan dinding ducting terhadap beban aksial dan lateral. Kegagalan pada pipa ducting ini berdampak pada kerugian dan unschedule shutdown proses produksi, meningkatkan biaya perbaikan, dan meningkatkan risiko kecelakaan kerja. Tindakan perbaikan yang direkomendasikan adalah penggunaan bahan pipa ducting yang tahan terhadap korosi, seperti stainless steel grade SS304. Selain itu, disarankan juga melakukan pemantauan kondisi pipa secara berkala, pembersihan debu proses secara teratur pada sisi dalam pipa ducting, dan pengendalian laju aliran debu pada sistem scrubbing. Langkah-langkah ini diharapkan dapat mengurangi risiko korosi untuk menjaga kekuatan ducting, sehingga meminimalisir kegagalan sistem dan menjaga kehandalan operasional pabrik pupuk NPK