bluuebunny/crossref_metadata_2025_split huggingface dataset:
Duplex Stainless Steel – Learning From Field Experience in Oil & Gas and Petrochemical Services
Authors: Dalal Mitul , Penso Jorge 
Published: November 2022

Abstract
Duplex stainless steels are a family of stainless steels. Named duplex (or austenitic-ferritic) grades because their metallurgical structure consists of two phases, austenite, and ferrite in approximately equal proportions. They are expected to provide better corrosion resistance, particularly chloride stress corrosion and chloride pitting corrosion, and higher strength than standard austenitic stainless steels such as Type 304 or 316. They are therefore used extensively in the offshore oil and gas and in the petrochemical industry in the form of piping and pressure vessels.
This paper describes some applications that ended up in failures and the importance to adhere to tight fabrications fabrication controls and consider the effect of common manufacturing and fabrication deviations in the expected material performance. The first one is a shell and tube heat exchanger. On the shell side the material choice was 2205 duplex stainless steel. The shell side fluid is fed from debutanizer which feeds from upstream high pressure and low-pressure low temperature separators. Overhead stream contains H2S, NH3, HCl. The duplex was selected for this exchanger to mitigate potential dew point NH4Cl corrosion. The shell ended up leaking in less than two years after being placed in service.
The second case is a super duplex 2507 seawater filter which failed after few weeks in service. Qualified welding procedures were not properly followed during fabrication leading to impaired corrosion resistant weldments.
The third case describes one more failure of a hydrocracker reactor effluent air cooler. Tube to tubesheet and partition plates to tubesheet welds failed after ∼ 20 years in service.
Evaluation of Localized Stresses at Spherical Pressure Vessel-to-Column Support Junction Using Closed-Form Equations
Authors: Manjrekar Vivek 
Published: November 2022

Abstract
Spherical pressure vessels (spheres) are widely used for storing liquids and gases at high pressures. The post plates of column-supported spheres are subjected to additional loads imposed by the supporting columns. The resulting localized stresses at column-to-post plate junction are difficult to analyze using analytical methods. Numerical techniques, such as the finite element method (FEM) are generally used to analyze the local discontinuity stresses.
In this work, a finite element parametric study is performed using a wide range of sphere geometries. The stresses at various locations around the column attachment are investigated. The influence of various loadings on the local stresses is also investigated. The internal membrane forces and bending moments obtained from the finite element model are then used to establish the dimensionless curves. A step-by-step procedure and the closed-form equations are provided to calculate membrane stresses, bending stresses and the combined stresses. A table of load factors is included to estimate the maximum vertical and horizontal loads on post plate due to wind or seismic forces. Finally, a sample problem is presented to illustrate the analysis procedure. Using this easy-to-use analysis approach, the design engineers will be able to calculate the localized stresses in sphere post plates without having to utilize the finite element method.
Computational Mechanics Based Validation of Crack Growth Approaches for Fracture Specimen Predictions
Authors: Kalyanam Sureshkumar , Hill Lance , Wilkowski Gery , Brust Frederick 
Published: November 2022

Abstract
The last several decades have seen growth in elastic-plastic fracture mechanics and the modeling of the behavior of structural steels employed in the nuclear, oil and gas, and other construction industries. Among these are a particular class of problems that provide challenges in modeling the physical behavior of structural steels using finite element modeling (FEM) approach that are based on microstructural damage and using parameters that depict the strain and stress states in the material region ahead of an existing crack. In this work, a recently experimented and investigated pipeline steel X80 material was modeled through two different fracture specimen geometries, namely single-edge-notch-tension, SEN(T) and compact-tension, C(T) to compare and contrast the predictions from two material damage models (microstructure and continuum based). The predictions from both these damage models that predict the ductile crack growth have been compared to the experimental findings of the crack growth (obtained using a d-c Electric Potential measurement technique), the corresponding load levels, and crack opening displacements (CODs). The points of similarity between the experimental measurements and the fracture surface observations of crack growth and the predictions from the FEM approach have been discussed. The same X80 material properties and damage model parameters were employed to predict the ductile crack growth in the two different fracture specimen geometries, SEN(T) and C(T) with a subtle change of one of the parameter values. This sheds light on the predictability of the crack initiation event and the subsequent ductile crack growth until failure using these damage models. The findings provide credence to the applicability of either model (after they are carefully tuned to arrive at optimized parameters) for piping materials while providing a framework for flaw evaluation methodologies. The investigation also opens the doors for regions where mesh regularization methods and modeling approaches along with mathematical relations can be developed to form a more efficient framework for modeling specimens with diverse constraints efficiently and develop material fracture resistance curves.
Machine Learning Models of Burst Strength for Defect-Free Pipelines
Authors: Zhu Xian-Kui , Johnson William R. , Sindelar Robert , Wiersma Bruce 
Published: November 2022

Abstract
Burst strength of line pipes is essential to pipeline design and integrity management. The simple Barlow equation with the ultimate tensile strength (UTS) was often used to estimate burst strength of line pipes. To consider the plastic flow effect of ductile steels, Zhu and Leis (2006, IJPVP) developed an average shear stress yield criterion and obtained the Zhu-Leis solution of burst strength for defect-free pipelines in term of UTS and strain hardening exponent, n, of materials. The Zhu-Leis solution was validated by more than 100 burst tests for various pipeline steels.
The Zhu-Leis solution, when normalized by the Barlow strength, is a function of strain hardening rate, n, only, while the experimentally measured burst strength, when normalized by the Barlow strength, is a strong function of n and a weak function of UTS and pipe diameter to thickness ratio D/t. Due to difficulty of three-parameter regressions, this paper adopts the machine learning technology to develop alternative models of burst strength based on a large database of full-scale burst tests. In comparing to the regression, the machine learning method works well for both single and multiple parameters by introducing an artificial neural network (ANN), activation functions and learning algorithm for the network to learn and make predictions.
Three ANN models were developed for predicting the burst strength of defect-free pipelines. Model 1 has one input variable and one hidden layer with three neurons; Model 2 has three input variables and one hidden layer with five neurons; and Model 3 has three input variables and two hidden layers with three neurons for the first hidden layer and two neurons for the second hidden layer. Those ANN models were then validated by the full-scale test data and evaluated through comparison with the Zhu-Leis solution and the linear regression result. On this basis, the best ANN model is recommended.
Evaluation of the API 579-1/ASME FFS-1 KPECL and KCECLL Stress Intensity Factors
Authors: Altstadt Steven 
Published: November 2022

Abstract
The API 579-1/ASME FFS-1 2016 Fitness-For-Service stress intensity factor solution for a plate with an embedded crack, infinite length, through-wall fourth order polynomial stress distribution (KPECL) was independently investigated in this work. Finite element models of cracked plates subjected to various applied stress fields were created and used to estimate stress intensity factors (K), which were then used to calibrate the respective influence coefficient values (Gi). The comparison of the newly calculated values to the existing values shows reasonable agreement for some values and a substantial difference for others. The new influence coefficients were also compared to values published by Le Delliou and Barthelet (2007) for the parameter combinations that exactly overlap with API 579-1/ASME FFS-1 2016. Excellent agreement was found with the new values presented herein. API 579-1/ASME FFS-1 2016 also recommends that the KPECL solution can be used for a cylinder with an embedded crack, longitudinal direction, infinite length, through-wall fourth order polynomial stress distribution (KCECLL) when the ratio of the internal radius (Ri) to wall thickness (t) is greater than or equal to five. As part of this work, influence coefficient values were also calculated for Ri/t = 5 and are included in this paper. A comparison of each KPECL value to its respective KCECLL value indicates that the recommendation is a reasonable approximation. The new influence coefficient values are recommended for fitness for service assessments that involve either the KPECL scenario or the KCECLL scenario where Ri/t ≥ 5.
Improvement of the ASME B&PV Code Resolution of Nonplanar Flaws in Pressure Retaining Components
Authors: Lacroix Valéry , Dulieu Pierre , Hasegawa Kunio , Mares Vratislav 
Published: November 2022

Abstract
When nonplanar flaws are detected in a component they are subjected not only to fracture mode I but to fracture modes I, II and III according to the direction of the load relatively to that of the flaws. Those fracture modes are induced by the relative displacement of crack faces as they are subjected to multi-axial loading. Consequently, the Stress Intensity Factors (SIFs) KI, KII and KIII corresponding to each of those modes should be accounted for in the flaw assessment. This is done in some Fitness-for-Service Codes that make provision to calculate an effective SIF.
In the ASME B&PV Code Section XI, a simplified approach is proposed: a nonplanar flaw is resolved into two planar flaws by projection of the flaw area into the planes normal to the maximum principal stresses. This approach allows simplifying the flaw assessment procedure as it deals only with KI SIF for which a lot of tabulated or closed-form solutions exist. However, the authors of this paper demonstrated recently that this simplified resolution of nonplanar flaws is not conservative for all types of loading and flaw inclinations. Consequently, an improvement of the resolution of nonplanar flaws must be provided in ASME B&PV Code Section XI.
In that frame, this paper carries out an exhaustive assessment of the conservatism of the ASME approach and then proposes an alternative approach to deal with nonplanar flaws allowing to overcome the non-suitability of the current ASME Code.
Empirical Correction Factor to Estimate the Plastic Collapse Bending Moment of Pipes With Circumferential Surface Flaw
Authors: Lacroix Valéry , Hasegawa Kunio , Li Yinsheng , Yamaguchi Yoshihito 
Published: November 2022

Abstract
The structural integrity assessment of pipes with circumferential surface flaw under the plastic collapse regime consists of net section collapse analysis. In recent years various researchers showed that this analysis, which has been developed based on classic beam theory, has certain inaccuracies. As such, assessment purely based on net-section collapse and beam theory can lead to both conservative and unconservative results.
To address those inaccuracies, in this paper the authors propose a correction factor which aims to mitigate the difference between the experimental results and ASME B&PV Code Section XI equations. This correction factor is calculated using an empirical formula developed on the basis of a large experimental database of pipe collapse bending tests containing variety of diameters, thicknesses, flaw depths and flaw lengths.
In this work, the authors took a systematic approach to identify the most influencing factors on such a correction factor and showed that by applying this correction factor to the current solution of ASME B&PV Code Section XI, the resulting solution becomes more accurate. This corrected approach also is in line with ASME B&PV Code Section XI Appendix C practice for axial flaw in pipes, where a semi-empirical correction factor has been considered as well.
Thermoelastic Analysis of Cylindrical Panels by Hyperbolic Heat Conduction
Authors: Pourasghar Aminallah , Brigham John 
Published: November 2022

Abstract
A three-dimensional approach is presented to analyze the thermoelastic behavior of a cylindrical panel subjected to transient heat conduction. First, the hyperbolic heat conduction equations are solved to obtain the temperature (and heat flux) in the spatial and temporal domain using the differential quadrature method (DQM) and Newton-Raphson method, respectively. The obtained temperature distribution is then applied in the three-dimensional thermoelastic equations of the cylindrical panel to obtain displacements and stresses at each time step by solving an eigenvalue problem. Numerical test cases showed that the proposed approach can estimate the temperature and deflection accurately. Although, the accuracy is dependent on the time increment and number of sampling grid points in the spatial and temporal domain of DQM.
Fatigue Damage Estimation From Pseudo-Random Load Sequence Generated for Metals and Fiber Reinforced Composites
Authors: Prakash Raghu V. , Patil Anurag Jeevan 
Published: November 2022

Abstract
Composite materials are widely used in many applications in view of tailor suiting of properties that include stiffness, toughness, and strength. Fatigue loading of components made of composites is inevitable. The theory to predict fatigue damage and fatigue life is well established for metals, while such a clear definition is not available for composites. The damage in composite can be due to matrix cracking, delamination, fiber fracture, matrix crazing, etc. The problem is complex when one considers pseudo-random load sequences like an aircraft spectrum.
This study evaluates the damage under a typical European Standard spectrum for Fighter Aircraft Loading STAndard for Fatigue and Fracture (FALSTAFF) as well as its programmed version. The phenomenological model proposed by Broutman and Sahu and empirical models proposed by Palmgren-Miner; Bond and Farrow; and Hashin-Rotem are used for calculating damage and fatigue life. Constant life diagrams are used for calculating the number of cycles to failure. The Range-Damage-Exceedance curve is employed to omit cycles from the FALSTAFF load sequence. It is observed that the Programmed FALSTAFF load sequence derived for metals is applicable for composites as both the full FALSTAFF spectrum and programmed version provide similar damage estimates. An increase in reference stress resulted in a decrease in fatigue life. Hashin-Rotem model is used to study sequence effect from the Programmed version of FALSTAFF. It is estimated that fatigue life under low-high load sequence is more as compared to high-low load sequence.
Study on Test and Evaluation Methods of Assembly Valve on High Pressure Hydrogen Storage Cylinder for HFCV
Authors: Gu Chunlin , Li Jun , Zhu Ming , Zhao Baodi , Li Jiepu , Li Xiang 
Published: November 2022

Abstract
In this paper, a comparative study is made on the test items and evaluation criteria stipulated in the relevant regulations and standards of hydrogen storage system valves and temperature-driven pressure relief devices (TPRD) for hydrogen fuel cell vehicle (HFCV). The similarities and differences are listed and analyzed. Based on the study and according to the characteristics of the assembly valve for HFCV (hereinafter referred to as the assembly valve), some suggestions on the test items, test methods and evaluation criteria settings for the assembly valve are discussed and the test strategy for assembly valve is proposed.
Piping Vibration Mitigation Comparison Using Snubbers and Struts
Authors: Saunders Kenneth L. , Onorato Michael 
Published: November 2022

Abstract
One of the typical characteristics of high temperature piping systems is that they are more flexible. This is due primarily to expansion stress limits which cause the piping designer to add additional elbows and to minimize axial or lateral stops. The resulting higher flexibility and lower frequency piping system is vulnerable to vibration loading which may result in excessive displacements, and hence, excessive stresses. Two options for reducing vibration displacements are adding snubbers or adding struts to the piping system. Both snubbers and struts will act as rigid components when subjected to vibration loading. The snubber has the advantage over the strut of being able to displace in all directions when the piping system is heated, thus allowing the expansion stresses to be minimized. Also, snubbers that are better suited for mitigating operational vibrations also have the advantage of being effective in all three orthogonal directions. The strut has the advantage over the snubber in that the installation cost is less. Two identical piping systems were both experiencing high vibration loading requiring the addition of vibration mitigation supports. One piping system was remediated with snubbers, and the other was remediated with struts. The resulting cost differences and the vibration response of these two piping systems will be discussed. Additionally, the challenges of making these two approaches most effective will be discussed.
Reheat Cracking of Low Alloy Steel During Fabrication and in Service in Oil and Gas Facilities
Authors: Dalal Mitul , Penso Jorge 
Published: November 2022

Abstract
Reheat Cracking is usually associated with the heat affected zone of restrained welded joints during either post weld heat treatment or elevated temperature service. Cracking is associated with the formation of fine intragranular precipitates. This precipitation strengthens the grain interiors and transfers the strain necessary for the relief of residual welding and system stresses to the grain boundaries. The overall effect is a reduction in creep ductility leading to intergranular failure in creep resistant steels. This mode of cracking poses a considerable practical problem particularly because the microstructural and compositional factors affecting its occurrence have not been clearly defined.
In this paper a literature review, case histories descriptions and research in progress are summarized.
The case histories include one overhead fluid catalytic cracking reactor overhead line during fabrication post weld heat treatment) and three high temperature high pressure steam piping after long and short term in service.
Research in progress includes the developing a testing procedure and the quantification of local strain level leading to stress relief cracking (SRC) during post weld heat treatment (PWHT) of welds in creep resistant steels. The testing approach involved implementation of a digital image correlation (DIC) technique with Gleeble-based SRC test.
Safety Advantages of Full-Containment Storage Tanks and the Cost-Effective Implementation for Refrigerated LPG Storage Systems
Authors: Fayez Amin A. , Morris Samuel N. , Alsubaikhy Hani A. , Refai Ali J. 
Published: November 2022

Abstract
Saudi Aramco has been a major player in the LPG (Propane and Butane) market since the 1960s and the company continues to be the source of benchmark pricing in the industry. A variety of refrigerated storage tank concepts have been developed to support international export of LPG products. Currently the industry has shifted to the use of safer full containment tank systems which have the capability to contain liquid and vapor release. Economic implementation of new tank systems has the potential of improving safety at company facilities. The benefit of the full containment storage tank is attractive given that the industry is focused on safety and environmental protection. However, the implementation of this technology is challenging due to the cost. Establishing selection criteria is important for economic implementation of any tank type. The paper explores the key design aspects of each type of tank arrangement based on risk assessment, project requirements and economic factors. The paper provides a case study of a current Saudi Aramco project being planned for new installation of LPG storage tanks at a size of one million barrels for both propane and butane services. The risk assessment examined the compliance, business interruption, environmental impact and other factors related to tank containment failures. The risk assessment and technoeconomic study demonstrates that the double steel full containment design is preferred over the prestressed concrete outer container with steel inner container. The double wall steel full containment tank system has been successfully deployed in facilities at sites around the world including at Marcus Hook, PA in the United Sates and Salalah in Oman. Single containment storage tank is not recommended for large scale of LPG storage or when tank is situated with other nearby facilities. Moreover, single containment type requires more plot area due to external diking requirements compared with double wall and full containment storage designs. Optimization of tank type selection may result in reduction of 6 to 8 months in project schedule and savings to the project of up to 70% of the storage tank installation cost. A risk assessment on different storage tanks designs reveals that the double steel wall full containment design is optimal from a cost and schedule prospective.
Slope Out Welding Development for Thick Section Electron Beam Welding for Pressure Vessel Applications
Authors: Dutilleul Thomas , Widdison Robert , Crossley John , Kyffin William , Albert Marc , Gandy David 
Published: November 2022

Abstract
As part of a Department of Energy (DOE) funded programme assessing advanced manufacturing techniques for SMR applications, the Nuclear AMRC and EPRI have been developing Electron Beam Welding (EBW) parameters and procedures based upon SA508 Grade 3 Class 1 base material.
For linear EB welds, the start and stop regions can be managed by using sacrificial run on/off blocks. However, for circumferential welds, such as joining shell to flange components, the use of sacrificial material is not possible. As such an effective method of closing the keyhole must be developed to ensure that weld defects are not entrained. This process is termed ‘slope out’ welding.
This paper presents results from the steady state welding in the 80–90 mm material thickness range, showing that weld properties meet specification requirements. Subsequently the paper describes the steps in developing an effective slope out welding procedure for circumferential welds. Weld quality was assured by Phased Array Ultrasonic Testing (PAUT) in conjunction with weld sectioning. All welds were assessed against ASME V requirements.
The results presented in this study clearly indicate that defect free and repeatable electron beam welds, including the slope out region, can be produced on thick section pressure vessel steel.