This work is about evaluation of creep characterizationsof INCOLOY 800H and it's weldmentwhich has high demand in use in Power Plant and Oil & Gas industries.
Small Punch Creep Test is used here to ...find the weakest location in creep consideration of INCOLOY 800H weldment. Tests are performed under 350 N, 450 N at temperature of 700° C.
Test specimens were machined from different parts of weldments and prepared in shape of thin disks including Base Metal, Weld Metal and HAZ (heat affected zone) near base metal. To verify the dependence of creep characterization to microstructure, the test results were compared to each other of each location.
•Heat affected zone is the weakest part in INCOLOY 800H weldment.•Base Metal and Weld Metal have higher life time than HAZ.•HAZ has about 20% lower life time than BM.
The stress corrosion cracking (SCC) susceptibility of longitudinal weldments of API-5L X-70 PSL1 pipeline steel in diluted bicarbonate solutions with and without the addition of chloride and sulfate ...ions by using slow strain rate tests (SSRTs) has been evaluated. The tests were complemented with potentiodynamic polarization curves, and hydrogen permeation measurements using the Devanathan-Stachurski method. Solution concentrations varied from 0.1 to 0.0001M NaHCO3. In addition, chloride (Cl-) and/or sulfate (SO42−) ions were added to the 0.01M NaHCO3 solution. Results showed a high corrosion rate and an increase in the hydrogen permeability rate in the 0.01 M NaHCO3 solution presented by the welding samples. The addition of Cl- ions increased the activity of the solution, but with the additions of SO42− ions, the metallic surface developed a passive layer that was associated with surface crack initiation. Analysis of fractured surfaces showed mainly of ductile rupture, but some indications of micro cracks and quasi-cleavage mode fracture characteristic of hydrogen embrittlement at the weldment were found in both the 0.001M NaHCO3 and 0.01M NaHCO3 with C1- +SO42−ion solutions.
In order to predict the corrosion depth of a district heating pipeline, it is necessary to analyze various corrosion factors. In this study, the relationship between corrosion factors such as pH, ...dissolved oxygen, and operating time and corrosion depth was investigated using the Box-Behnken method within the response surface methodology. To accelerate the corrosion process, galvanostatic tests were conducted in synthetic district heating water. Subsequently, a multiple regression analysis was performed using the measured corrosion depth to derive a formula for predicting the corrosion depth as a function of the corrosion factors. As a result, the following regression formula was derived for predicting the corrosion depth: "corrosion depth (μm) = -133 + 17.1 pH + 0.00072 DO + 125.2 Time - 7.95 pH × Time + 0.002921 DO × Time".
Weld seams are critical points for the initiation of fatigue cracks in steel structures subjected to cyclic loads. Semi-elliptical surface cracking at the toes of a fillet weld is not easily found ...when it is partially through the thickness and subcritical. In this study the acoustic emission (AE) method is used to detect crack propagation in cruciform fillet welded joints that are representative of typical fatigue sensitive details in steel bridge superstructures. The effect of geometry and fatigue load on the AE data is investigated by varying the width of the base plate and the stress ratio. AE data filtering based on load pattern, source location, and waveform feature analysis was implemented to minimize noise-induced AE signals and false indications due to wave reflections. AE time domain features such as amplitude (b-value), counts, signal strength, and absolute energy are employed to study the influence of geometry and fatigue load on the AE data.
•A combined approach for acoustic emission (AE) data filtering is presented.•AE of fatigue cracks in cruciform welded joints is characterized.•The effect of geometry and fatigue load on the AE is investigated.•Active fatigue cracks with higher load ratio lead to stronger AE.•The AE intensity is not affected by the width of the welded joints.
The corrosion behavior of a Ti6321 weldment was investigated for the first-time ever in a deep sea environment with low temperature and low dissolved oxygen content. Electrochemical test results ...indicated that the corrosion resistance of the weldment deteriorated significantly in the deep seawater. This was especially true for the heat affected zone, which provided initial sites for pitting corrosion. The results of x-ray photoelectron spectroscopy measurements revealed that the corrosion film in the deep sea was less oxidized (the oxygen content of the deep-sea weldment was 10%–17% lower than that of the shallow-sea weldment). This can be attributed to the low dissolved oxygen content and the low temperature in the deep sea environment, which led to an increase in the defect density of the corrosion film on the surface. Consequently, deterioration in the anti-corrosion properties of the weldment was observed.
In this paper, a structural analysis with Weldment Structural Members is performed. Halfen Company provides solutions for pipes support. The assembled support structures are characterized by ...increased stiffness, their elastic deformations being reduced. The identification of stress and deformation fields is done by finite element analysis. The purpose is to create a finite element model, to find the best shape of a pipes support using SolidWorks. It is very important to avoid oversizing the support.
In this paper, a structural analysis with Weldment Structural Members is performed. Halfen Company provides solutions for pipes support. The assembled support structures are characterized by ...increased stiffness, their elastic deformations being reduced. The identification of stress and deformation fields is done by finite element analysis. The purpose is to create a finite element model, to find the best shape of a pipes support using SolidWorks. It is very important to avoid oversizing the support.
This study aims to clarify how filler-typed metals which were ERNiCrMo-3 and ERNiCrMo-4 affect corrosion resistance characteristics in the weldment of super austenitic stainless steel joints under ...the simulated desulfurization environment for ships. The desulfurization environment includes high temperature, chlorides, and acidic conditions, which, inevitably, can cause severe corrosion to great extent. For exact clarification, the variations of microstructure and the composition distribution in the weldment before and after welding was examined by using scanning electron microscope and energy dispersive X-ray spectroscopy. Then, the corrosion resistance characteristics were comparatively evaluated through the cyclic potentiodynamic polarization test together with potential measurement under the desulfurization simulated environments. In addition, the correlation between passive film and corrosion resistance characteristics was investigated after identifying the formed features of the passive film through the X-ray photoelectron spectroscopy analysis. Through these studies, it made certain, ERNiCrMo-4 filler metal with high Mo content is advantageous for the formation of MoO
3
oxide on the surface, which belongs to form a stable passive film and maintains the corrosion resistance characteristics under the simulated desulfurization environment.
Abstract The study focused on the importance of the different welding parameters on the mechanical behavior of High Strength Steel (HSS) X65 steel pipes by reviewing the advantages of parameter ...optimization for the Tungsten Inert Gas (TIG) - Metal Inert Gas (MIG) welding processes. The parameters considered in the study include welding speed, welding current, welding voltage and gas flowrate of the welding. The effects of improper selection and parameter optimizations were highlighted and illustrated using different metallurgical and mechanical instances. The outcome of the study indicates that adequate parameter optimization aids in obtaining good weld quality with adequate mechanical and microstructural properties. Furthermore, it helps in the determination of variation in hardness in the heat affected zone as well as the base metal. Thus, this study provides insight to welding engineers on the importance of parameter optimization in the welding of steel pipe.
This paper refers to linear static analysis of truss and beams structures modelled in SolidWorks. In SolidWorks truss and frame elements are available only for staticstudies. For illustration it was ...modelled and studied the behaviour of a support of pipe. The truss is a welded structure modelled with Weldment Structural Members and it is often found in industrial constructions. During this study, there have been investigated the following FEA steps: Pre-Processing, Processing and Post-Processing.The results of this study are images corresponding to Axial Stress and The Maximum Displacement in different situations.
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