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Service Life Analysis of Control Valve far Automatic Turbine Startup of Thermal Power Plant

화력 발전소 증기 터빈의 자동기동을 위한 주증기 제어 밸브 수명해석

  • Published : 2002.01.01

Abstract

The automatic turbine startup system provides turbine control based on thermal stress. During the startup, control system monitors and evaluates main components of turbine using damage mechanism and life assessment. In case of valve chest, the temperature of inner/outer wall is measured by thermo-couples and the safety of these values are evaluated by using allowable △T limit currie during the startup. Because allowable ΔT limit curve includes life assessment, it is possible to apply this curve to turbine control system. In this paper, low cycle fatigue damage, combined rupture and low cycle fatigue damage criterion were proposed for yielding the allowable ΔTf limit curve of CV(control valve) chest. To calculate low cycle fatigue damage, the stress analysis of valve chest has been performed using FEM. Automatic turbine startup to assure service life of CV was achieved using allowable ΔT limit curve.

Keywords

Thermal Stress;Low Cycle Fatigue;Rupture Damage;Control Valve;Steam Turbine;ΔT limits

References

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