ANALISIS PENGARUH PERUBAHAN TEMPERATUR PADA INNER BORE TERHADAP TEMPERATUR PADA TITIK SEALING DAN KEMAMPUAN GASKET DALAM MENERIMA MECHANICAL STRESS DAN THERMAL STRESS PADA D-FLANGE 13 5/8 10M
DITO NANDIAN P, Dr. Khasani, ST., M.Eng.
2014 | Skripsi | TEKNIK MESINDalam proses pengeboran sumur minyak dan gas, Blow Out Prevention (BOP) berfungsi sebagai sistem keamanan yang dipasang di atas wellhead untuk menghindari terjadinya Blow Out. BOP dihubungkan dengan wellhead menggunakan BOP Riser. Koneksi antara wellhead dengan BOP Riser menggunakan koneksi flange. Pada Two in One Splitter-Unitized Wellhead System, setiap single wellhead tidak berbentuk Circular-Wellhead namun berbentuk D-Wellhead. Desain BOP Riser menyesuaikan dengan wellhead, sehingga flange yang digunakan pada D-Wellhead berbentuk D-Flange. Ketika terjadi perubahan temperatur pada inner bore maka gasket di dalam koneksi flange mengalami thermal stress di titik sealing. Sehingga total stress yang dialami gasket adalah mechanical stress yang berasal dari bolt torque dan thermal stress yang berasal dari perubahan temperatur. Berdasarkan latar belakang tersebut, perlu dilakukan analisis kemampuan material gasket dalam menerima total stress sehingga dapat diketahui apakah total stress yang diterima melebihi compressive strength material gasket atau tidak. Analisis ini dilakukan menggunakan software SolidWorks 2012 untuk mengetahui simulasi penyebaran temperatur pada titik sealing dan selanjutnya dilakukan perhitungan manual untuk mengetahui nilai total stress yang terjadi pada titik sealing. Simulasi dilakukan pada 12 nilai temperatur inner bore yaitu 100 oF, 150 oF, 200 oF, 250 oF, 300 oF, 350 oF, 400 oF, 450 oF, 500 oF, 550 oF, 600 oF, dan 650 oF. Dari analisis yang dilakukan, didapatkan hasil bahwa nilai total stress maksimum terjadi pada kondisi temperatur inner bore sebesar 650 oF dengan nilai thermal stress sebesar 1.417,647 psi, nilai mechanical stress sebesar 49.332,048 psi, dan nilai total stress sebesar 50.749,695 psi. Nilai total stress maksimum yang terjadi lebih kecil dibanding nilai compressive strength material gasket sebesar 73.200 psi, sehingga dapat disimpulkan bahwa material gasket pada koneksi D-Flange 13 5/8 10M mampu menerima total stress yang terjadi pada perubahan temperatur hingga 650 oF. Kata Kunci: Blow Out Prevention, Wellhead, BOP Riser, D-Flange, gasket, thermal stress, mechanical stress, compressive strength
In the oil and gas drilling process, Blow Out Prevention (BOP) is used as the safety system that is installed above the wellhead to prevent Blow Out. BOP is connected to the wellhead using BOP Riser. The connection between wellhead and BOP Riser using flange connection system. In case of Two in One Splitter-Unitized Wellhead System, each of single wellhead is not in Circular-Wellhead form but it is in D-Wellhead form. BOP Riser design is suited to wellhead, so, flange that is used in D-Wellhead is in D-Flange form. When there is a change of temperature at the inner bore, gasket will receive thermal stress in sealing point of flange connection. So, gasket will receive total stress in the form of mechanical stress from bolt torque and in the form of thermal stress from the change of temperature. Based on this background, analysis of the ability of gasket in receiving total stress is needed to know whether the total stress is exceed the compressive strength of gasket or not. This analysis was conducted using SolidWorks 2012 to make simulation of temperature distribution on sealing point, and then make calculation to get the value of total stress on sealing point. Simulation was conducted on 12 value of temperature of inner bore, which are 100 oF, 150 oF, 200 oF, 250 oF, 300 oF, 350 oF, 400 oF, 450 oF, 500 oF, 550 oF, 600 oF, and 650 oF. From this analysis, it showed that the maximum total stress occurs in the condition of temperature of inner bore is at 650 oF with the value of thermal stress is 1.417,647 psi, the value of mechanical stress is 49.332,048 psi, and the value of total stress is 50.749,695 psi. Maximum total stress is less than the compressive strength of gasket which is 73.200 psi, so it can be concluded that gasket on D-Flange 13 5/8 10M connection can receive the total stress that occurs on elevated temperature until 650 oF. Keywords: Blow Out Prevention, Wellhead, BOP Riser, D-Flange, gasket, thermal stress, mechanical stress, compressive strength
Kata Kunci : Blow Out Prevention, Wellhead, BOP Riser, D-Flange, gasket, thermal stress, mechanical stress, compressive strength
