Description:
Abstract. Crude oil transportation activities generally use pipelines. The pipes used are made of metal. Metal pipes are used because they have good resistance to high temperatures and pressures. Metal pipes can experience quality degradation caused by corrosion due to direct contact with the external and internal environment. Losses caused by corrosion on the pipe is the reduction in pipe thickness which can cause the pipe to leak and the remaining useful life of the pipe to be low. Therefore, monitoring is needed, one of which is the study of corrosion in crude oil transportation pipelines so that crude oil transportation activities are not disrupted. This research was conducted on the crude oil transportation pipeline along 2,700 m which is above ground level and below ground level. This study aims to determine the type of corrosion, corrosion control methods applied, the corrosion rate, and the remaining service life of the pipe. Observations were made on the surrounding environmental conditions in the form of an acidic environment with a soil pH of 5.7 - 6.3, an ambient temperature of 22.9 22C - 30°C, and soil resistivity of 2.369 – 3.634 Ω, included in the very corrosive category - corrosive. Measurement of the actual thickness of the pipe is done by using the Ultrasonic Thickness Gauge Panametrics MG 2 DL at 15 test points. The methodology used in this study is to use data relating to pipes for safety to determine the level of corrosion and the remaining life of the pipe. Based on the pipe thickness reduction data, the corrosion rate and the remaining service life of the pipe can be calculated. The type of corrosion that occurs in crude oil transportation pipelines is uniform corrosion and erosion corrosion. Corrosion control methods applied externally are the coating method using Rust-Oleum Stops Rust Enamel Brush, the wrapping method using Polyken The Berry Plastics CPG System 942/955 EN, and the cathodeic protection method for sacrificial anodes (SACP) using Magnesium metal as sacrificial anode. While internally the inhibitor method uses UOP TM UNICOR TM C. The corrosion rate in the pipe is 0.1422 - 0.2322 mm / year included in the good category based on its relative corrosion resistance. The remaining service life of the pipe is 19.21 - 42.75 years, so the pipe can still operate beyond the design life of the pipe 20 years.Keywords : Steel Pipe, Crude Oil, API 570, Corrosion Rate, Design Age of the pipe, Remaining Service Life of the Pipe. Abstrak. Kegiatan transportasi crude oil pada umumnya menggunakan jalur-jalur pipa. Pipa-pipa yang digunakan tersebut berbahan dasar logam. Pipa logam digunakan karena memiliki ketahanan yang baik terhadap temperatur dan tekanan yang tinggi. Pipa logam dapat mengalami penurunan kualitas yang diakibatkan oleh korosi karena kontak langsung dengan lingkungan eksternal dan internal. Kerugian yang ditimbulkan oleh korosi pada pipa ialah terjadinya pengurangan ketebalan pipa yang dapat menyebabkan pipa tersebut mengalami kebocoran dan sisa umur pakai pipa menjadi rendah. Oleh karena itu, diperlukan monitoring salah satunya ialah kajian mengenai korosi pada pipa transportasi crude oil agar kegiatan transportasi crude oil tidak terganggu. Penelitian ini dilakukan pada pipa transportasi crude oil sepanjang 2.700 m yang berada di atas permukaan dan di bawah tanah. Penelitian ini bertujuan untuk mengetahui jenis korosi, metode pengendalian korosi yang diaplikasikan, laju korosi (Corrosion rate), dan sisa umur pakai (Remaining Service Life) pipa. Kondisi lingkungan pada lokasi penelitian yaitu pH tanah 5,7 – 6,3 yang termasuk asam, suhu lingkungan yaitu 22,9°C – 30°C, dan resistivitas tanah 2.369 – 3.634 ohm.cm, termasuk dalam kategori highly corrosive - corrosive. Pengukuran tebal aktual pipa dilakukan dengan menggunakan alat Ultrasonic Thickness Gauge Panametrics MG 2 DL pada 15 test point. Metodologi penelitian ini adalah pengukuran pengurangan ketebalan pipa untuk menentukan laju korosi (Corrosion rate) dan sisa umur pakai (Remaining Service Life) pipa. Jenis korosi yang terjadi pada pipa transportasi crude oil ialah korosi merata (unifrom corrosion) dan korosi erosi (errosion corrosion). Metode pengendalian korosi yang diaplikasikan secara eksternal ialah metode coating menggunakan Rust-Oleum Stops Rust Enamel Brush, metode wrapping menggunakan Polyken The Berry Plastics CPG System 942/955 EN, dan metode proteksi katodik anoda korban (SACP) menggunakan logam Magnesium sebagai anoda korban. Sedangkan secara internal ialah metode inhibitor menggunakan UOP TM UNICOR TM C. Laju korosi pada pipa ialah 0,1422 - 0,2322 mm/tahun termasuk ke dalam kategori good berdasarkan ketahanan korosi relatifnya. Sisa umur pakai pipa ialah 19,21 - 42,75 tahun, dengan demikian pipa masih dapat beroperasi melebihi umur desain pipanya yaitu 20 tahun. Kata Kunci: Pipa Baja, Crude Oil, API 570, Laju Korosi, Umur desain pipa, Sisa Umur Pakai Pipa.