Remaining Creep Life Assessment of Service Superheat Tube Boiler

Abstract:

The demand of remaining life assessment of the boilers arises from technical, economic, and legal reasons. Creep is major damage mechanism of primary superheat tube boiler during prolong operation at high temperature and pressure in a water tube boiler. This paper presents the calculation method for the remaining life assessment due to creep damage. The service-exposed primary superheat tube made of 2.25Cr-1Mo steels. During scheduled inspection, wall thickness measurement, metallographic investigation by replica technique, design data and operating condition were used to estimate the remaining life in the form of creep damage accumulation rate calculated from life fraction using Larson-Miller Parameter. The results indicate that the primary superheat tubes satisfy in extension service life. By attaining an accurate and timely discussion of the results, the engineer can manage the maintenance and inspection schedule for the critical part in the boiler.

• Periodical: Key Engineering Materials (Volume 659)
• Pages: 686-690
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.659.686
• Online since: August 2015
• Authors: Pornsak Thasanaraphan*, Pannawat Thapnuy, Duangporn Ounpanich, Pratip Vongbandit
• Keywords: Creep, Damage Mechanism, Primary Superheat Tube, Remaining Life Assessment

References

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