복합발전 증기터빈 고중압 케이싱의 Hogging 변형 특성 및 정렬 영향 평가 = Characteristics of HIP Casing Hogging Deformation and Its Effect on Alignment in a Combined Cycle Steam Turbine

다국어 초록 (Multilingual Abstract)

In the steam turbine for combined cycle power generation operated for a long time, thermal and mechanical deformation is accumulated in the High-Intermediate Pressure (HIP) casing due to repeated start-up and stop under high temperature and high pressure conditions. This study attempted to quantitatively evaluate the deformation characteristics based on the measured data and analyze the effect of casing deformation on casing alignment and inner gap.
To this end, the level of the horizontal split flange surface was precisely measured and analyzed for the two decomposed steam turbine high-pressure casing of the combined thermal power plants.
As a result, Hogging deformation occurred throughout the casing, and a maximum strain deviation of 0.83mm between the upper and lower casings was confirmed, and an asymmetric deformation tendency was confirmed in which the upper part was more than twice as large as the lower part. Based on this phenomenon, by estimating the amount of centerline movement and the change in the inner gap that can occur during assembly due to the upper and lower deviation of the casing Hogging deformation, it was confirmed that Hogging deformation is a major influencing factor on casing alignment.