Syahran, Muhammad Fadhilah (2019) Analisis Stabilitas pada Subsea Pipeline akibat Free Span dan Vortex Induced Vibration: Studi Kasus Produciton Gas Pipeline di Selat Madura. Other thesis, Institut Teknologi Sepuluh Nopember.
Preview |
Text
04311540000046-Undergraduate-thesis.pdf Download (3MB) | Preview |
Abstract
Pipeline adalah teknologi yang banyak digunakan untuk distribusi minyak dan gas. Seiring waktu, teknologi pipeline tidak hanya di darat, tetapi juga di lepas pantai. Dalam pengoperasiannya, banyak permasalahan-permasalahan yang dihadapi sehingga dapat menyebabkan kegagalan pada pipeline. Salah satu permasalahan yang sering terjadi pada pipeline yang dapat mengakibatkan kegagalan adalah free span. Free span diakibatkan oleh kontur dasar laut yang tidak teratur, sehingga menyebabkan pipa terbentang bebas diantara dua tumpuan. Dengan adanya bentangan bebas dan beban lingkungan yang bekerja disekitar pipeline, maka akan timbul VIV (vortex induced vibration) di sekitar pipeline. Maka dari itu, diperlukan analisis free span static dan dinamik beserta tegangan kombinasinya dengan mengacu pada kode standar DNV RP F105, DNV OS F101 dan ASME B31.8. Pada studi kasus ini, terdapat 31 titik span yang perlu dianalisis. Dari hasil analisis dinamik, terdapat 15 titik span yang perlu penambahan support dikarenakan tidak memenuhi kriteria yang disyaratkan DNV RP F105. Sementara untuk tegangan kombinasi, tegangan paling besar yang terjadi adalah pada span dengan panjang 49.9 m dengan nilai tegangan kombinasinya adalah 177.93 MPa, dimana nilai tersebut masih dibawah batas maksimum tegangan ijin yaitu 405 MPa, sehingga pipeline masih dalam batas aman.
================================================================================================================================
Pipeline is a technology that is widely used for oil and gas distribution. Over time, pipeline technology is not only on land, but also offshore. In its operation, many problems are encountered so that it can cause failure in the pipeline. One problem that often occurs in the pipeline that can cause failure is free span. Free span is caused by irregular contours of the seabed, causing the pipe to stretch freely between the two supports. With the free stretch and environmental load acting around the pipeline, VIV (vortex induced vibration) will occur around the pipeline. Therefore, analysis of free span static and dynamic and combined stress is required by referring to the standard code DNV RP F105, DNV OS F101 and ASME B31.8. In this case study, there are 31 span points that need to be analyzed. From the results of the dynamic analysis, there are 15 span points that need additional support because they do not meet the required criteria from DNV RP F105. While for the combined stress, the greatest stress that occurs is at a span of 49.9 m with a combined stress value of 177.93 MPa, where the value is still below the allowable stress of 405 MPa, so the pipeline is still within safe limits.
| Item Type: | Thesis (Other) |
|---|---|
| Additional Information: | RSKe 665.544 Sya a-1 2019 |
| Uncontrolled Keywords: | Subsea Pipelime, Free span, Vortex Induced Vibration, analisa tegangan, combined stress |
| Subjects: | T Technology > TC Hydraulic engineering. Ocean engineering > TC1680 Offshore structures T Technology > TJ Mechanical engineering and machinery > TJ930 Pipelines (General). Underwater pipelines. |
| Divisions: | Faculty of Marine Technology (MARTECH) > Ocean Engineering > 38201-(S1) Undergraduate Thesis |
| Depositing User: | Muhammad Fadhilah Syahran |
| Date Deposited: | 29 May 2023 02:16 |
| Last Modified: | 29 May 2023 02:16 |
| URI: | http://repository.its.ac.id/id/eprint/63997 |
Actions (login required)
 |
View Item |