Fitness-for-service assessment for pressurized components-general metal loss

• Main Author: Tan, Cheng Siong.
• Other Authors: Ong Lin Seng
• Format: Final Year Project
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/45944
• Institution: Nanyang Technological University

According to (Holtan, Baxter, Ashcroft, & Thomson, 2011), a Fitness-for-Service (FFS) assessment is “a quantitative engineering evaluation performed to demonstrate the structural integrity of an in-service component that may contain a flaw or damage.” For the project, the FFS assessment will be applied to components suffering from general metal losses, which are losses arising from corrosion. First of all, the design code API 579-1/ASME FFS-1 is briefly reviewed and discussed. The different categories of detection techniques used are also assessed and the merits of adopting the assessment procedure are examined. Through the assessment process chart, the reader is provided with a clearer picture of the purpose and application procedure of a Fitness-for-Service assessment. The various approaches recommended in the design code will also be used to evaluate the remaining life evaluation of a component. The FFS assessment procedures are demonstrated through the means of two examples. These two examples related to corrosion flaws which are commonly found on a pressure vessel. The reliability of the results computed through the use of different approaches (thickness, MAWP and FEA) is deliberated. Finally, the results will be analysed and conclusions are drawn with regards to the suitability of different remaining life evaluation approaches.