Combined Effect of Material and Environment Factors on Flow Accelerated Corrosion and Oxide Film Property of Carbon Steel Pipes

One of the more common modes of degradation in power plant piping has been wall thinning due to erosion-corrosion or flow-accelerated corrosion. Extensive work has been performed to understand flow-accelerated corrosion mechanisms and develop fracture criteria of locally thinned pipes, since the tragic events at Surry Unit 2 and Mihama Unit 3. A large number of tests have been performed on carbon steel pipes, elbows and tees with local wall thinning. In addition, the American Society of Mechanical Engineers Boiler and Pressure Vessel Code provides procedures in Code Case N-597-2 for evaluation of wall thinning in pipes. This paper provides validation of the evaluation procedures in Code Case N-597-2 by comparing with the field rupture data and pipe burst test data. The allowable wall thinning from the Code Case N-597-2 procedures is shown to maintain adequate margins against rupture.

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Assessment of Piping Field Failures and Burst Tests on Carbon Steel Pipes With Local Wall Thinning Using ASME Section XI Code Case N-597-2

Journal of Pressure Vessel Technology ◽

10.1115/1.4002498 ◽

2011 ◽

Vol 133 (3) ◽

Cited By ~ 2

Author(s):

Kunio Hasegawa ◽

Toshiyuki Meshii ◽

Douglas A. Scarth

Keyword(s):

Carbon Steel ◽

Accelerated Corrosion ◽

Steel Pipes ◽

Pipe Burst ◽

Evaluation Procedures ◽

Wall Thinning ◽

American Society ◽

Corrosion Mechanisms ◽

Flow Accelerated Corrosion ◽

Local Wall Thinning

One of the more common modes of degradation in power plant piping has been wall thinning due to erosion-corrosion or flow-accelerated corrosion. Extensive work has been performed to understand flow-accelerated corrosion mechanisms and develop fracture criteria of locally thinned pipes since the tragic events at Surry Unit 2 and Mihama Unit 3. A large number of tests have been performed on carbon steel pipes, elbows, and tees with local wall thinning. In addition, the American Society of Mechanical Engineers Boiler and Pressure Vessel Code provides procedures in Code Case N-597-2 for the evaluation of wall thinning in pipes. This paper provides validation of the evaluation procedures in Code Case N-597-2 by comparing with the field rupture data and pipe burst test data. The allowable wall thinning from the Code Case N-597-2 procedures is shown to maintain adequate margins against rupture.

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Impact of Internal Pipe Grooves on Flow-Accelerated Corrosion of Small-Bore A-106 Carbon Steel Pipes

Journal of Failure Analysis and Prevention ◽

10.1007/s11668-017-0237-z ◽

2017 ◽

Vol 17 (3) ◽

pp. 417-425 ◽

Cited By ~ 1

Author(s):

A. H. Bagheri ◽

S. Nasrazadani ◽

H. Bostanci

Keyword(s):

Carbon Steel ◽

Accelerated Corrosion ◽

Steel Pipes ◽

Flow Accelerated Corrosion

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Analytical Investigation of Deaerator Steam Inlet Nozzle Corrosion Allowance in a CANDU Station

Volume 2: Structural Integrity; Safety and Security; Advanced Applications of Nuclear Technology; Balance of Plant for Nuclear Applications ◽

10.1115/icone17-75617 ◽

2009 ◽

Author(s):

Ali Keshavarz ◽

Andrew K. Ali ◽

Randy K. Lall

Keyword(s):

Finite Element ◽

Carbon Steel ◽

Stress Analysis ◽

Analytical Investigation ◽

Percentage Error ◽

Metal Loss ◽

Fe Model ◽

Accelerated Corrosion ◽

Materials Properties ◽

Flow Accelerated Corrosion

Flow-accelerated corrosion (FAC) is a phenomenon that results in metal loss from piping, vessels and equipment made of carbon steel. This metal loss can lead to stress to occur at the steam inlet nozzle side, where it is located at the side of the deaerator. This paper presents a method to find the thickness critical of the steam inlet nozzle. A Finite Element (FE) model of the pressure vessel head was created to perform a stress analysis using NX Nastran 5.0. By applying materials properties, loads and constraints to the model, the results obtained are required to satisfy the following criterion: vonMises≥SySy=YieldStrength The results obtained from the stress analysis were analyzed to obtain a corrosion allowance and it was compared to the recommended value from a normal deaerator design, which is roughly 0.25 inches. From the FE model, and by continuously reducing the thickness of the nozzle, it was determined that the corrosion allowance is 0.229 inches, and that the percentage error was 8.4%.

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