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Picture for Fatigue and Fracture Resistance of Different Line Pipe Grade Steels in Gaseous H2 Environment
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Fatigue and Fracture Resistance of Different Line Pipe Grade Steels in Gaseous H2 Environment

Product Number: 51324-21101-SG
Author: Milan Agnani; Chris San Marchi; Joseph Ronevich
Publication Date: 2024
$40.00
The existing natural gas (NG) pipeline network is being considered to transport pure gaseous hydrogen (GH2) or blends of NG and GH2 for domestic and industrial energy needs, in an effort to reduce global CO2 emissions. The toughness and ductility of ferritic steels are reduced in the presence of GH2. In order to assess the viability of GH2 gas distribution via NG pipeline networks, it is necessary to understand the fatigue and fracture response of the materials in the network, including the various pipeline steels. Hydrogen-assisted fatigue crack growth (FCG) and fracture behavior of five different modern line pipe grade steels (X52, X70, X80, X100, and X120) were evaluated in high-purity GH2 at pressure of 210 bar, where the tensile strength increases with grade, X120 displaying the highest strength. The X52 and X70 steels feature ferrite with small amounts of pearlite in the microstructure. The X80 steel has a combination of polygonal and acicular ferrite, whereas the X100 and X120 steels contain fine ferritic and bainitic microstructures. The different pipeline steels exhibit similar accelerated FCG rates in the presence of GH2, irrespective of the strength and microstructural constituents. A significant reduction in the fracture resistance is observed for all the steels in GH2 as compared to air, although elastic-plastic fracture (J-R) behavior is maintained in GH2. Contrary to FCG rates, hydrogen-assisted fracture is affected by the microstructure and strength of the steel; higher strength steels exhibit lower fracture resistance and lower tearing modulus, analogous to the generally expected trends in air. Selected fracture surfaces are analyzed to rationalize the influence of microstructure and strength on hydrogen-assisted fracture of this class of steels.
Picture for On The Load Ratio Equation in API TR 5C3 for Evaluation of Pipe Body Fracture Performance
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On The Load Ratio Equation in API TR 5C3 for Evaluation of Pipe Body Fracture Performance

Product Number: 51321-16567-SG
Author: Bisen Lin/ David Coe
Publication Date: 2021
$20.00
Picture for Reliability Methods for Fracture Verification of Pipelines Subject to Lateral Buckling
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Reliability Methods for Fracture Verification of Pipelines Subject to Lateral Buckling

Product Number: MPWT19-15030
Author: Abdul Rahman El-Chayeb, Faris Ragheb Kamal, Don Xiaodong Wang, Oussama Takieddine
Publication Date: 2019
$0.00

Recent project experiences in the Arabian Gulf Region have shown that weld fracture is the governing limit state for subsea pipelines subject to lateral buckling loads. This is due to the small axial strain limits which can be allowed to minimize impact on weld repair rate for offshore pipeline installation. Considering the absence of reported weld fracture failures due to lateral buckling, it is possible that the safety margins used in fracture verification due to buckling can be further optimized. For instance, in a recent work scope to validate an existing pipeline for higher operating temperature it was found that the maximum allowable strain would be 0.252%. This was less than the 0.4% strain limit associated with radiographic NDT as considered at the design stage when the pipeline was installed in 2012. In other work scopes, the maximum allowable strain due to lateral buckling was 0.18% which is also significantly less than the historic 0.4% used in pipeline design codes and standards. The above supports the argument that although pipeline fracture analysis procedures are fully mature and well established, these procedures do not necessarily capture the complexities involved in dealing with pipelines susceptible to lateral buckling taking into account the statistical distributions of buckle location along the pipeline route, defect location, defect size, material strength, crack growth constants and a number of other parameters. This paper outlines a procedure for implementing fracture verification of pipelines susceptible to lateral buckling based on probabilistic approach. It is shown that this procedure can reduce the conservatism in the deterministic approach usually used and can help reduce unnecessary weld repairs during pipe-lay operations

Picture for Remaining Life Calculations and Crack Growth Rate for Various Forms of Stress Corrosion Cracking as a Function of Temperature
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Remaining Life Calculations and Crack Growth Rate for Various Forms of Stress Corrosion Cracking as a Function of Temperature

Product Number: 51321-16490-SG
Author: Jeffery Lord/ Jeffery C. Gibeling
Publication Date: 2021
$20.00
Picture for The Susceptibility of Prestressing Strands Within Grouted Post-Tensioned Tendons to Hydrogen Embrittlement: A Review
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The Susceptibility of Prestressing Strands Within Grouted Post-Tensioned Tendons to Hydrogen Embrittlement: A Review

Product Number: 51321-16869-SG
Author: Mahmood Aliofkhazraei; David Dukeman; Christopher L. Alexander
Publication Date: 2021
$20.00