Thermal Growth Prediction on 4 MW Steam Turbine Casing Using Finite Element Method Dwijaya Febriansyah(1*), Endra Dwi Purnomo(1), Budi Nofiyantoro Fadjrin(1), Rudias Harmadi(1), Cuk Supriyadi Ali Nandar(1)
1. Agency for Assessment and Application of Technology (BPPT - Republik Indonesia), PUSPIPTEK, Serpong 15314, Indonesia
Abstract
Adjustment of shaft alignment in steam turbine installations is an important procedure in carrying out preventive maintenance. The shaft alignment specification consists of a coupling target which is the distance between the shaft and the bearing then thermal growth which depends on the operating temperature and the material used. In the new steam turbine, the value of thermal growth can be calculated theoretically, but in fact, experience has proven that this method has missed a lot, whereas when using the experimental method (hot & cold alignment), the costs are quite large. To solve this problem, predicting the value of thermal growth can be done by simulating thermal expansion using the finite element method. In this study, the lower casing steam turbine simulates its thermal expansion according to its operating temperature so that the value and direction of deformation due to thermal expansion are known. The simulation results of this prediction give the thermal growth value on 4 MW steam turbine foots 0.021 mm (foot 1) and -0.055 mm (foot 2).
