Studi Numerik Pengaruh Dimensi Grooving Dan Variasi Material Terhadap Overheat Turbin Uap PLTU

Setiawan, Andika (2026) Studi Numerik Pengaruh Dimensi Grooving Dan Variasi Material Terhadap Overheat Turbin Uap PLTU. Masters thesis, Institut Teknologi Sepuluh Nopember.

Text 6007241024-Master_Thesis.pdf - Accepted Version Restricted to Repository staff only until 26 November 2026. Download (9MB) | Request a copy

Abstract

Thrust bearing, sebagai komponen kritis yang menahan beban aksial rotor turbin, mengalami overheating di PLTU Tenayan hingga mengakibatkan unit trip. Kondisi tersebut disebabkan oleh tekanan uap yang berlebihan sehingga meningkatkan perpindahan aksial (axial displacement) rotor. Untuk mengatasi permasalahan tersebut, dilakukan pembuatan alur (grooving) pada permukaan bearing dengan variasi kedalaman 0,5 mm, 1,0 mm, dan 1,5 mm serta modifikasi komposisi material Babbitt. Studi ini menggunakan simulasi numerik berbasis metode elemen hingga (Finite Element Method/FEM) untuk menganalisis kinerja dan umur pakai thrust bearing melalui pendekatan Fluid–Structure Interaction (FSI) dan ANSYS Fatigue Tool. Model yang digunakan mencakup variasi komposisi material Babbitt, terutama timah (Sn), antimon (Sb), dan tembaga (Cu). Material awal ASTM B23 Grade 3 dibandingkan dengan ASTM B23 Grade 2 dan material modifikasi ASTM B23 Grade 2 yang memiliki tingkat kekerasan lebih tinggi. Hasil penelitian menunjukkan bahwa grooving sedalam 1,5 mm mampu mengurangi overheating, tetapi menyebabkan penurunan umur pakai dan keandalan thrust bearing. Oleh karena itu, desain grooving sedalam 0,5 mm yang dikombinasikan dengan material ASTM B23 Grade 3 memberikan performa operasional terbaik.
========================================================================================================================================
The thrust bearing, a critical component responsible for supporting the axial load of the turbine rotor, experienced overheating at the Tenayan Coal-Fired Power Plant, resulting in a unit trip. This condition was attributed to excessive steam pressure, which increased the axial displacement of the rotor. To address this issue, grooves with depths of 0.5, 1.0, and 1.5 mm were introduced on the bearing surface, and the composition of the Babbitt material was modified. This study employed finite element method (FEM)-based numerical simulations to evaluate the bearing performance and service life using a Fluid–Structure Interaction (FSI) approach and the ANSYS Fatigue Tool. The model incorporated variations in the Babbitt material composition, particularly its tin (Sn), antimony (Sb), and copper (Cu) contents. The original ASTM B23 Grade 3 material was compared with ASTM B23 Grade 2 and a modified ASTM B23 Grade 2 material with higher hardness. The results demonstrated that the 1.5 mm groove effectively reduced the operating temperature and prevented overheating; however, it also reduced the fatigue life and reliability of the thrust bearing. Therefore, the combination of a 0.5 mm groove and ASTM B23 Grade 3 provided the best overall operational performance.

Item Type:	Thesis (Masters)
Uncontrolled Keywords:	Thrust bearing, Grooving depth, , Finite Element Analysis
Subjects:	T Technology > TJ Mechanical engineering and machinery
Divisions:	Faculty of Industrial Technology and Systems Engineering (INDSYS) > Mechanical Engineering > 21101-(S2) Master Thesis
Depositing User:	Andika Setiawan
Date Deposited:	04 Aug 2026 08:01
Last Modified:	04 Aug 2026 08:01
URI:	http://repository.its.ac.id/id/eprint/143707

Actions (login required)

View Item