Analisis Kegagalan Komponen Drill Collar pada Drill String dengan Material Baja AISI 4145H di Lingkungan Sumur Minyak Bumi

Wicaksono, Allezandro Lellakhi (2025) Analisis Kegagalan Komponen Drill Collar pada Drill String dengan Material Baja AISI 4145H di Lingkungan Sumur Minyak Bumi. Other thesis, Institut Teknologi Sepuluh Nopember.

Text 5011211093-Undergraduate_Thesis.pdf - Accepted Version Restricted to Repository staff only Download (5MB) | Request a copy

Abstract

Drill collar merupakan salah satu bagian penting dalam drill string yang berfungsi untuk memberikan beban pada mata bor agar dapat menembus formasi bawah tanah dengan lebih efektif serta menjaga kestabilan lubang bor. Drill collar umumnya terbuat dari baja paduan berkekuatan tinggi, seperti baja AISI 4145H, tetapi dalam kondisi operasi yang ekstrem, drill collar rentan mengalami kegagalan. Penelitian ini bertujuan untuk menganalisis kegagalan drill collar pada drill string berbahan AISI 4145H melalui berbagai pengujian. Uji penetrant menunjukkan tidak ada multiple initiation crack, dan uji optical emission spectroscopy menunjukkan komposisi kimia sesuai standar API SPEC 7-1. Pengujian mekanis yaitu tensile, hardness, dan impact menunjukkan bahwa nilai sifat mekanis komponen drill collar masih memenuhi standar API SPEC 7-1, dengan hasil spesimen menandakan bahwa komponen drill collar bersifat ductile. Penurunan kekerasan terjadi di zona patahan akhir. Sampel uji imersi pada kondisi high pressure high temperature tidak menunjukkan penurunan signifikan terhadap sifat mekanis. Hasil uji imersi membentuk uniform corrosion pada sampel dan ketahanan korosi terhadap laju korosi dalam kategori good. Mikrostruktur komponen drill collar berupa sorbite dengan sementite berbentuk spheroid halus, serta morfologi sampel titik patahan menunjukkan transgranular crack. Kegagalan berupa fatigue fracture terjadi karena adanya titik awal crack pada akar ulir drill collar, diakibatkan oleh pembebanan fluktuatif pada area connection sebagai area dengan konsentrasi tegangan tertinggi. Crack menjalar akibat pembebanan yang berlangsung, menuju ke dua arah hingga hampir mencapai setengah lingkaran drill collar, lalu patah statis terjadi karena komponen tidak lagi mampu menahan beban sisa akibat dimensi ketebalan drill collar bagian ulir yang lebih kecil dibandingkan bagian badan komponen drill collar yang tidak berulir. Faktor korosi, yaitu interaksi antara komponen drill collar dengan brine, tidak memengaruhi terjadinya kegagalan.
=======================================================================================================================================
Drill collar is an important part of the drill string that serves to provide a load on the drill bit in order to penetrate underground formations more effectively and maintain the stability of the borehole. Drill collars are generally made of high-strength alloy steel, such as AISI 4145H steel, but under extreme operating conditions, drill collars are prone to failure. This study aims to analyze the failure of drill collars on drill strings made of AISI 4145H through various tests. Penetrant tests showed no multiple crack initiation, and optical emission spectroscopy tests showed chemical composition according to API SPEC 7-1 standards. Mechanical testing, namely tensile, hardness, and impact, shows that the mechanical properties of the drill collar component still meet the API SPEC 7-1 standard, with the specimen results indicating that the drill collar component is ductile. The decrease in hardness occurs in the final fault zone. Immersion test samples at high pressure high temperature conditions did not show a significant decrease in mechanical properties. The immersion test results formed uniform corrosion on the sample and corrosion resistance to corrosion rate in the good category. The microstructure of the drill collar component is sorbite with fine spheroidal cementite, and the morphology of the fracture point sample shows transgranular crack. Failure in the form of fatigue fracture occurs due to the crack starting point at the root of the drill collar thread, caused by fluctuating loading in the connection area as the area with the highest stress concentration. The crack spreads due to ongoing loading, heading in both directions until it almost reaches half the drill collar circle, then static fracture occurs because the component is no longer able to withstand the residual load due to the dimensions of the drill collar thickness of the threaded part which is smaller than the unthreaded part of the drill collar component body. The corrosion factor, the interaction between the drill collar component and the brine, did not affect the failure.

Item Type:	Thesis (Other)
Uncontrolled Keywords:	Analisis Kegagalan, Drill Collar, Patahan, Retak, Crack, Drill Collar, Failure Analysis, Fracture
Subjects:	T Technology > TA Engineering (General). Civil engineering (General) > TA169.5 Failure analysis
Divisions:	Faculty of Industrial Technology > Material & Metallurgical Engineering > 28201-(S1) Undergraduate Thesis
Depositing User:	Allezandro Lellakhi Wicaksono
Date Deposited:	01 Aug 2025 02:40
Last Modified:	01 Aug 2025 02:40
URI:	http://repository.its.ac.id/id/eprint/125145

Actions (login required)

View Item