Pressurized vessels such as a steam drum in a typical power plant can often experience in-service cracking. Structural integrity assessment methodology can be a useful tool to determine the suitability of a vessel for service. This methodology may include fitness-for-service and remaining useful life analyses of a vessel based on the nondestructive examination (NDE) results and operating conditions. In this paper, the structural integrity assessment methodology applied to a steam drum case study is described. The analysis procedure, material property determination, stress analysis, limiting flaw size evaluation, and remaining useful life evaluation for the drum are discussed. A thermal shock design tool is briefly introduced. Recommendations for appropriate action are also presented. The assessment methodology employed in this paper can be applied to other similar pressurized vessels and structures in power plants.

Issue Section:
Research Papers
Keywords:
structural engineering, power plants, pressure vessels, steam plants, remaining life assessment, stress analysis, nondestructive testing
Topics:
Fracture (Materials), Fracture (Process), Nondestructive evaluation, Service life (Equipment), Steam, Stress, Thermal shock, Vessels, Power stations, Design, Pressure, Transients (Dynamics), Fitness-for-service, Stress analysis (Engineering), Hoop stress, Cycles, Materials properties
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Copyright © 2006
 by American Society of Mechanical Engineers
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