Anilisis penyebab pipa terjepit pada sumur X lapangan Y pertamina hulu energi

DETAIL KOLEKSI

Anilisis penyebab pipa terjepit pada sumur X lapangan Y pertamina hulu energi

Oleh : Jessica Edlyn Pramono

Info Katalog

Nomor Panggil : 873/TP/2018

Penerbit : FTKE - Usakti

Kota Terbit : Jakarta

Tahun Terbit : 2018

Pembimbing 1 : Abdul Hamid

Pembimbing 2 : Pauhesti Rusdi

Subyek : Drilling mud - Oil technic - Research;Stuck pipe - Pertamina Hulu Energy

Kata Kunci : cement plug, jar, loss circulation, work on pipe

Status Posting : Published

Status : Lengkap

File Repositori

No.	Nama File	Hal.
1.	2018_TA_TM_071001400186_Halaman-Judul.pdf	18
2.	2018_TA_TM_071001400186_Bab-1.pdf	2
3.	2018_TA_TM_071001400186_Bab-2.pdf
4.	2018_TA_TM_071001400186_Bab-3.pdf
5.	2018_TA_TM_071001400186_Bab-4.pdf
6.	2018_TA_TM_071001400186_Bab-5.pdf
7.	2018_TA_TM_071001400186_Daftar-Pustaka.pdf	1
8.	2018_TA_TM_071001400186_Lampiran.pdf

Abstrak
Abstract

O perasi pemboran pada suatu sumur bertujuan untuk memperoleh minyak dan gas agar bias mengalir dari bawah permukaan ke permukaan. Terdapat tiga jenis pemboran, yaitu pemboran vertikal, berarah, dan horisontal. Pemboran ditujukan untuk mencapai kedalaman yang diinginkan, yang telah dikalkukasikan bahwa minyak dan gas berada pada kedalaman tersebut. Tujuan dari operasi pemboran adalah menyiapkan lubang sumur yang akan menjadi saluran minyak dan gas untuk mengalir. Proses pemboran harus dilakukan secara ekonomis, namun pada kenyataannya, operasi pemboran tidak selalu berjalan sesuai yang direncanakan tanpa adanya hambatan. Ketika rangkaian pipa pemboran tidak dapat ditarik ke atas, diturunkan ke bawah, atau diputar, rangkaian pipa diinterpretasikan telah terjepit. Berdasarkan studi literatur, pipa terjepit dapat terjadi karena jepitan diferensial dan mekanis.Pemboran Sumur X direncanakan agar dapat mencapai ke kedalaman yang diinginkan secara aman dan ekonomis, untuk memperoleh minyak dan gas. Pemboran diharapkan tidak menjumpai masalah, namun, ada hal merugikan yang terjadi selama proses pemboran Sumur X. Kerugian ini terdiri dari kehilangan alat pemboran dan waktu operasional yang produktif.Pemboran pada Sumur X terletak pada Barat Laut Jawa diharapkan dapat berlangsung tanpa masalah, sehingga produksi minyak dan gas dapat berlangsung secara efektif dan efisien. Saat lubang 8Â½â€ dibor, terdapat masalah hilangnya sirkulasi dan terjepitnya pipa. Penulis akan menganalisa penyebab pipa terjepit untuk mengetahui apa penyebab dari masalah tersebut dan apa saja yang dipengaruhi karena masalah pipa terjepit tersebut. Parameter yang akan ditinjau lebih dalam adalah penggunaan semen plug, zat perendam yang digunakan, peralatan pemboran yang tertinggal, waktu ekonomis fishing, dan biaya kerugian.Berdasarkan analisa yang dilakukan, pipa terjepit disebabkan oleh jepitan mekanis karena mengerasnya semen. Kehilangan sirkulasi terjadi ketika operasi pemboran, sehingga digunakan semen plug untuk menangani masalah kehilangan sirkulasi, karena LCM tidak cukup. Semen plug yang ketiga dipompakan, kemudian rangkaian pipa dicabut, namun pada kedalaman 6197 feet, rangkaian tidak bisa dilanjutkan untuk dicabut. 20 barrel sebelum menyelesaikan pemompaan, ada kenaikan tekanan dan torsi, lalu rangkaian pipa tidak bisa dicabut kembali. Pemompaan lumpur, penarikan rangkaian, pemompaan fluida perendam, maupun jarring ke atas dan ke bawah gagal untuk melepas jepitan pipa. Jar tidak dapat bekerja karena jar telah tertimbun oleh semen yang sudah mengeras. Posisi jar berada di kedalaman 5827.1 feet, dan ketinggian puncak semen berada pada kedalaman 5036 feet. Berdasarkan hasil free point indication, kedalaman pipa yang bebas berada pada kedalaman 4952.2 feet, dan ketinggian puncak desco (fluida perendam) berada pada 4330.8 feet. Hal ini menunjukan bahwa fluida perendam telah mencapai titik kedalaman pipa terjepit, namun tidak sukses dalam melepaskan jepitan tersebut.Metode yang digunakan untuk menyelesaikan masalah jepitan pipa adalah melakukan sidetrack karena jepitan sudah tidak bisa dilepas. Pipa dipotong dan dipasangkan whipstock untuk membuat sudut baru agar pemboran bisa dimulai kembali. Rangkaian pemboran yang tertinggal di dalam lubang bor terdiri dari alat yang mahal, seperti MWD, LWD, dan RSS. Dimana alat tersebut tidak bisa diangkat ke permukaan karena sulitnya melepaskan jepitan. Terjepitnya pipa terjadi pada 4 November dan sidetrack dilakukan pada 12 November agar tidak melewati batas waktu ekonomis fishing, yaitu 8 hari. Masalah terjepitnya pipa pada Sumur X menyebabkan waktu dan biaya operasional yang bertambah besar, ditambah dengan alat yang tertinggal didalam lubang sumur. Biaya kerugian total mencapai hampir 6.9 Juta USD.

D rilling a well is conducted to derive oil or gas to flow from subsurface to surface. Three types of drilling include vertical drilling, directional drilling, and horizontal drilling. Drilling is intended to reach desired depth that has been calculated where the oil or gas reservoir is. The main purpose of drilling a well is to prepare wellbore in order to flow oil and gas from subsurface to surface without any obstacle. Producing oil and gas should be economical. However, drilling operation doesnâ€™t always go smoothly without any trouble. When drill string is no longer able to move up, move down, or rotate, stuck pipe is indicated. Based on literature, stuck pipe is caused by plenty of parameters, such as differential sticking, hole pack off, wellbore geometry, and junk in hole.Drilling is intended to reach the final measured depth safely and economically, to aim for hydrocarbon in form of oil and gas, which will be produced in a period of time. Drilling is expected to be accomplished with no obstacle, however, in fact, everything doesnâ€™t always happen as what we expect, likewise, in drilling operation. There must be a lot of matter that interrupt the operation which is very disadvantageous. To be detailed, these involves disadvantages in equipment, time, and cost. One of problem on drilling operation is stuck pipe, in which pipe movement is restricted in the wellbore, either pipe canâ€™t be rotated and lifted, or, pipe can be rotated but not lifted. This will result in restriction of operation, increase of expenses to release stuck and addition of rig cost.Well X, which is located on North West Java, is planned to be drilled without any problem so oil and gas production can be done effective and efficiently. However, while drilling 8 Â½â€ hole section, there were several problems occurred and one of them is pipe sticking issue. Writer of this final assessment will analyze the cause of stuck pipe in order to know what leads to stuck pipe and how it affects the effectiveness in drilling operation. Some parameters which are going to be discussed are cement plug usage, immersion substance usage, fish left in hole, economic fishing time, and disadvantage cost.In fact, in the following after doing some study and research, stuck is found to be caused by mechanical pipe sticking due to green cement. Total loss happened while drilling, so that cement plug was spotted to cope with it because LCM canâ€™t get over it. Unfortunately, when cement plug was pumped in order to combat total loss, string cannot be pulled out while pulling out of hole after the third cement plug pumping. Before finishing the last 20 bbl of cement plug spotting, there was pressure and torque increase and string could no longer be pulled out since then.Working on pipe, circulating, jarring up and down, and immersing do not solve the stuck pipe. Jar didnâ€™t work because it has been buried with the hardened cement plug. Jar was positioned at 5827.1 feet while the top of cement plug was at 5036 feet. Based on free point indication result, desco pill (immersion fluid) usage can be analyzed that it didnâ€™t work properly. Based of free point indication result, the depth of free pipe was at 4952.2 feet and the top of spotted desco pill was at 4330.8 feet, so it reached the depth of stuck but it didnâ€™t succeed in freeing the stuck pipe.The method used to resolve the issue is sidetracking due to the inability of resolving the stuck pipe issue. Pipe was backed off and whipstock was set in order to build new angle for drilling to restart. Fish that was left on hole consisted of high-priced tools, such as MWD, LWD, and RSS, which couldnâ€™t be recovered due to its difficulties in releasing the stuck. Stuck happened at November 4th and sidetrack was performed at November 12th, due to its limitation of economic fishing time at 8 days. Due to this issue, drilling operational time has extended and several tools has been left in the hole, making total cost disadvantage reached to about USD 6.9 Million.