Journal articles: 'Pipe stress analysis'

1

Choi, Kwang. "Analysis of Welding Residual Stress of Steel Pipes." Materials Science Forum 580-582 (June 2008): 637–44. http://dx.doi.org/10.4028/www.scientific.net/msf.580-582.637.

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This study was aimed at evaluation of residual stress of steel pipe structures. The production process of pipes was complex (at first bending was done by roll forming or press forming and welding was final process of making of steel pipes). So there could be expected high residual stresses in steel pipes. In order to evaluate the changes of residual stress measurements of residual stress were done for the circular pipe (thickness 16 mm). For the evaluation of residual stress, holedrilling method (ASTM E837) was applied. The results showed that along the weld line high tensile stress were measured as expected, and high tensile stresses were measured where large plastic deformation developed. And in order to assist the experimental results, numerical method (finite element method) was applied. In finite element analysis, non-linear analysis of processes was considered. In welding (final case of pipe making), thermal-elastic-plastic analysis was done considering material properties according to temperature. The calculations showed there were good agreements with experimental results. And from results, experimental results could be more effectively assisted through numerical method in welded pipes production.

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Rajole, S., P. R. Sondar, S. Hiremath, and K. S. Ravishankar. "Failure Analysis of Industrial Discharge Hopper Pipe." Journal of Modern Manufacturing Systems and Technology 5, no. 1 (November 16, 2020): 1–6. http://dx.doi.org/10.15282/jmmst.v5i1.5149.

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This work presents the detailed investigation and root cause analysis of catastrophic failure of an industrial discharge hopper pipe. The hopper pipe investigated in the present work is made of austenitic stainless steel, 316 grade, a commonly used grade for valves, pipes and heat exchanger tubes. The pipe fractured in transverse direction, leading to the failure of discharge pipe. Visual inspection, dye penetrant test, chemical analysis, microstructural analysis, and fractography analysis were carried out on the failed part and it was concluded that stress corrosion cracking led to the failure of hopper pipe. The pipe constantly being under the exposure of industrial water and the presence of chlorine content in it made it susceptible for stress corrosion cracking. Transgranular fracture was clearly observed in the microstructure of failed sample and spot EDX at the fracture location confirmed the presence of chlorine content. Further, fractography showed striations indicating fatigue loading. The work concluded that stress corrosion cracking as the root cause of failure.

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Kannappan, S., and H. Saunders. "Introduction to Pipe Stress Analysis." Journal of Pressure Vessel Technology 110, no. 3 (August 1, 1988): 340–41. http://dx.doi.org/10.1115/1.3265613.

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Wang, Wenhao, Wenxuan Gou, Fusheng Wang, Wei Liu, and Zhufeng Yue. "Buckling Analysis on a Pipe Conveying Fluid under Two Stresses." Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University 36, no. 6 (December 2018): 1202–8. http://dx.doi.org/10.1051/jnwpu/20183661202.

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Pressure pipes have broad applications in aviation, space flight, mechanical engineering, industrial and civil architecture etc. Instability destruction is their main failure mode. Firstly, in this paper, a complex fluid-solid coupling problem was simplified as a buckling problem of a pipe under two stresses which were along the pipe wall. The two stresses consisted of a compressive stress which was perpendicular to the pipe wall and a tangential stress which was parallel to the pipe wall. Secondly, the buckling performs of the pressured pipe were discussed by finite element analysis method under a working state and an off-working state, respectively. Some obtained conclusions were drawn as follows by the analysis in this paper.1). Provided the tangential stress is unchanged, by increasing compressive stress eigenvalue buckling critical load increases and nonlinear buckling critical load decreases.2). Provided the compressive stress is unchanged, when the direction of the tangential stress is same as that of the axial pressure, by increasing the absolute value of tangential stress the buckling critical load decreases; provided the compressive stress is unchanged, when the direction of the tangential stress is in the opposite direction of the axial pressure, by increasing the absolute value of tangential stress the buckling critical load increases.

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Rajab, M. D., and Akram Zahoor. "Tearing Modulus Analysis for Pipes Containing Constant Depth Internal Flaw." Journal of Engineering Materials and Technology 113, no. 1 (January 1, 1991): 156–61. http://dx.doi.org/10.1115/1.2903372.

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The pipe displacement and tearing modulus solutions are derived for pipes containing a uniform depth internal flaw under bending moment or axial loading. The tearing modulus solution is derived for both load control and displacement control conditions. These solutions are then used to construct critical stress curves for various flaw sizes for a carbon steel pipe. These curves are useful in predicting the onset of flaw growth instability. Critical stress curves can be similarly constructed for other materials and pipe geometries.

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Lee, Kuang Chyi, Yuan Cheng Liang, and Chien Chang Lin. "Analysis for Repairing the Cracked PVC Pipe." Materials Science Forum 505-507 (January 2006): 565–70. http://dx.doi.org/10.4028/www.scientific.net/msf.505-507.565.

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This paper proposes a stress analysis model for the cracked PVC pipe. The cracked PVC pipe is rehabilitated with an inner composite epoxy material by a dig-free method. The optimal thickness which can get the maximal flow rate after rehabilitated will be found by the finite element model. When the crack width of the pipe with 324 degree crack angle is 30 mm, the optimal thicknesses will be obtained with the compression ratio of 5%. The optimal thicknesses of theφ 300 ,φ 400 , φ 500 and φ 600 PVC pipes are 0.6, 0.8, 1.1 and 2.5 mm respectively. With these optimal thicknesses, the flow rates of rehabilitated pipes are lager than 98% the flow rates of original pipes.

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Park, Soo, Hui Hwan Kwon, Jae Mean Koo, Chang Sung Seok, Du Han Jung, and Jin Yong Mo. "A Study on the Fatigue Life Prediction for Bending Pipe." Advanced Materials Research 415-417 (December 2011): 2219–25. http://dx.doi.org/10.4028/www.scientific.net/amr.415-417.2219.

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Mechanical structures with power sources experience repeated force produced by motors. As a result, the life of the pipes reduces and ultimately, the pipes collapse. In most cases, the U-shape pipe is made from a straight pipe by complicated bending work. During this work process, plastic deformation of the pipe produces residual stress in the pipe. The residual stress significantly affects the fracture behavior of the pipe. In this paper, fatigues tests of U-shape bending pipe are performed by uniaxial testing machine and residual stresses were evaluated by FEM analysis. So we established the relation between residual stress and fatigue life. And we suggested new equation for fatigue life prediction using the residual stress of U-shape bending pipe.

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KIM, SANG-YOUNG, JAE-MEAN KOO, and CHANG-SUNG SEOK. "EVALUATION OF RESIDUAL STRESS OF COPPER PIPE BY USING RAMAN SPECTROSCOPY." Modern Physics Letters B 22, no. 11 (May 10, 2008): 1007–12. http://dx.doi.org/10.1142/s0217984908015759.

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In most cases, a straight pipe is used after complicated bending work in a mechanical system. In this work process, the plastic deformation of the pipe produces residual stress in the pipe. This residual stress significantly affects the behavior of pipe fracture. For this reason, residual stress must be evaluated. Measuring the residual stress of a U-shaped copper pipe is difficult with existing destructive and nondestructive measurement methods. In this paper, the residual stress of a U-shaped copper pipe (99.9% pure copper) was evaluated from the Raman shift by Raman spectroscopy and FEM analysis. Also, the results of the bending test by FEM analysis and experiments are compared. The analyzed results of Raman spectra had a similar tendency with the results of the FEM analysis in regard to the residual stress distributions in the U-shaped pipes. Also, the results of the bending tests were shown resemblance.

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Harley, C., and A. Faghri. "Two-Dimensional Rotating Heat Pipe Analysis." Journal of Heat Transfer 117, no. 1 (February 1, 1995): 202–8. http://dx.doi.org/10.1115/1.2822304.

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A detailed transient numerical simulation of rotating heat pipes is presented. This two-dimensional, axisymmetric formulation accounts for the thin liquid condensate film on the inner surface of the rotating pipe wall, the vapor flow in the vapor space, and the unsteady heat conduction in the pipe wall. The thin liquid film is coupled to the vapor velocity at the liquid–vapor interface, and the effects of the vapor pressure drop and the interfacial shear stress are included in the Nusselt-type condensation analysis.

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Sun, Jian Cheng, Ya Jing Pang, and Wen Zhong Zhao. "FEM Analysis of Massive Concrete Pile Using of Cooling Pipe in Shahe Bridge." Applied Mechanics and Materials 501-504 (January 2014): 1359–63. http://dx.doi.org/10.4028/www.scientific.net/amm.501-504.1359.

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Based on finite element theory,Study on temperatrue field under the using of cooling pipe for massive concrete pile in shahe bridge by using MIDAS/CIVIL.Analysis of various factors effect to the temperature field, stress field and the temperature gradient of massive concrete pile,which included in inlet water temperature and the water flow, proposed the control indicators of cooling pipe design.

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Edmund, Jonathan Emmanuel, and Zahiraniza binti Mustaffa. "Numerical Analysis of Crack Failure of Reinforced Thermoplastic Pipe (RTP)." MATEC Web of Conferences 203 (2018): 01023. http://dx.doi.org/10.1051/matecconf/201820301023.

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Composite pipeline can drastically reduce losses caused by corrosion that occurs in carbon steel pipes in the industry. Multiple numerical testing has been conducted to determine maximum stress and strain a Reinforced Thermoplastic Pipe (RTP) can withstand before hitting failure. Not many studies were done to find the maximum stress intensity a defected RTP can resist before failing. Objectives are to validate the numerical model for Reinforced Thermoplastic Pipeline (RTP) to industry standard and to analyze the maximum stress intensity of Reinforced Thermoplastic Pipes (RTP) can withstand with various size of defects under constant pressure and incremental internal pressure with constant crack defect. Results were, under constant internal pressure of 6 MPa, the pipe will fail with a defect length of 2.05mm and at constant design pressure of 10 MPa, the pipe will fail with a defect length of 0.3mm. At constant crack depth and width, crack tip propagation (failure) is more dependent on internal pressure rather than crack length. However, when comparing the severity of crack depth to internal pressure, crack depth is the major cause of failure.

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12

Jiang, Changliang, Pengchao Chen, Rui Li, and Xiaoben Liu. "A Multisource Monitoring Data Coupling Analysis Method for Stress States of Oil Pipelines under Permafrost Thawing Settlement Load." Mathematical Problems in Engineering 2020 (November 24, 2020): 1–15. http://dx.doi.org/10.1155/2020/6696680.

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Thaw settlement is one of the common geohazard threats for safe operation of buried pipelines crossing permafrost regions, as pipes need to bear additional bending stress induced by settlement load. In the presented study, a novel coupled data analysis method was proposed for stress state estimation of buried steel pipeline under thawing settlement load. Multisource data including pipe bending strain derived by inertial measurement unit, pipe longitudinal strain derived by strain gauges, and thawing displacement loads derived by soil temperature monitoring were used to estimate the pipe’s mechanical states. Based on the derived data, finite element method-based pipe soil interaction model was established to predict pipe’s actual stress distribution. A monitored pipe segment of one crude oil pipeline in northeast China operated since 2010 was adopted as a prototype for the investigation, monitoring data derived in the last ten years was employed to predict the settlement loading, and relative accurate stress results was obtained via the established pipe soil interaction model. The mean absolute error (MAE) of the predicted pipe stresses compared with the monitoring results in 2014, 2017, and 2018 are 5.77%, 12.13%, and 13.55%, respectively. Based on the analyzed stress results, it can be found that the investigated pipe was subjected to an increasing settlement load from 2010–2016, made the bending stress increased up to 149.5 MPa. While after 2016, due to the depth of frost soil in this area is no more than 3.5 m, the thawing settlement load almost remained constant after 2016. As the investigated pipe is made by X65 line pipe steel, the von-Mises stress in pipe is much smaller than the allowable one indicating pipe’s structural safety status so far. The proposed method can also be referenced in the status monitoring of buried pipeline crossing other geological hazard regions.

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Sellakumar, S., and R. Venkatasamy. "Stress Analysis of Oval Pipe Bend with Attached Pipe using Finite Element Analysis." Asian Journal of Research in Social Sciences and Humanities 6, no. 10 (2016): 1868. http://dx.doi.org/10.5958/2249-7315.2016.01135.7.

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Naveen, Janjanam, A. Eswara Kumar, and M. Nagaraju. "Analysis of Fluid Structure Interaction in High Pressure Elbow Pipe Connections." Applied Mechanics and Materials 813-814 (November 2015): 1075–79. http://dx.doi.org/10.4028/www.scientific.net/amm.813-814.1075.

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Pipes in power plants generally subjected to high pressures and temperatures. These are connected by elbow, T-joints to get the continuity between different stages. Due to excessive joints the outlet velocity and pressure will drops by considerable amount. Stresses will be produced due to high pressure and temperature of fluid flow, which in turn creates the failure of the pipes. The turbulence of the fluid passing through the pipes will also plays a vital role to decide the outlet pressure and velocity. In this present study pipes are connected by the elbow joint are considered and observed the effect of pipe thickness, turbulence intensity and length of elbow on outlet pressure, velocity, von mises stress and turbulence kinetic energy. It results that with increase in pipe thickness and length of elbow, the velocity, von mises stress and turbulence kinetic energy are decreases but with increase in turbulence intensity, the velocity and turbulence kinetic energy are increases.

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15

Sawa, T., N. Higurashi, and H. Akagawa. "A Stress Analysis of Pipe Flange Connections." Journal of Pressure Vessel Technology 113, no. 4 (November 1, 1991): 497–503. http://dx.doi.org/10.1115/1.2928786.

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The use of pipe flange connections is standardized in the codes of JIS, ASME, DIN and so on. However, these codes are almost entirely dependent on experience, and subsequently some problems concerning pipe flange connections have been encountered. In the present paper, the distribution of contact stresses which governs the sealing performance is analyzed as a three-body contact problem, using an axisymmetrical three-dimensional theory of elasticity. The effects of the stiffness and the thickness of raised face metallic gaskets on the contact stresses and the effective gasket seating width are shown by numerical calculation. Moreover, stresses produced on the hub, the load factor (the relationship between an increment of bolt axial force and an internal pressure), and the maximum stress caused in bolts are analyzed. For verification, experiments are carried out. The analytical results are satisfactorily consistent with the experimental results.

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ITO, Hiroshi, Norimasa CHIBA, Yuji ISHIDA, Kunio ENOMOTO, and Hiroshi KIMOTO. "Residual Stress Analysis of Plastically Expanded Pipe." Proceedings of the 1992 Annual Meeting of JSME/MMD 2000 (2000): 145–46. http://dx.doi.org/10.1299/jsmezairiki.2000.0_145.

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17

Raatz, Sascha, Michael Kaack, Peter Staron, Norbert Schell, Andreas Schreyer, Manuela Klaus, Christoph Genzel, and Katharina Theis-Bröhl. "Comparison of Synchrotron Radiation Diffraction and Micromagnetic Stress Analysis in Straightened Steel Pipes." Materials Science Forum 777 (February 2014): 225–30. http://dx.doi.org/10.4028/www.scientific.net/msf.777.225.

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The use of magnetic Barkhausen noise (MBN) and harmonic analysis (HA) as non-destructiveevaluation (NDE) techniques in the industrial environment increased in the last years. In our study,we evaluated the potential of those methods to measure residual stress on the surface of straightenedsteel pipes. To study the influence of the pipe manufacturing process and the following straighteningprocess we used pipes of three different straightening levels. The straightening was done with differentparameters, which resulted in a plastic deformation that leaves a visible helix on the surface of thepipes. High energy diffraction experiments were performed to obtain absolute values of residual stresson the surface and in the bulk of the pipe samples. With these residual stress values our MBN and HAdata was calibrated. The surface of all pipes showed high compressive stresses while the highest tensilestresses were 0.5 to 1.4 mm under the surface. The stresses correlate to greater plastic deformationduring the straightening process.

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Reid, S. R., and J. L. Yang. "Non-linear dynamic analysis of cantilever whipping pipes." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 212, no. 3 (August 1, 1998): 133–49. http://dx.doi.org/10.1243/0954408981529367.

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This paper presents the results of numerical dynamic analyses of a number of pipe whip problems based on non-linear shell theory using the DYNA3D (version 6.0) finite element code. The calculations are mainly concerned with the transient deformation of the pipes during the whipping process. The main purpose of the study is to check the efficacy of a recently published theoretical elastic-plastic, hardening-softening (e-p-h-s) model for pipe whip developed by Reid et al. [1, 2]. This model is based upon beam theory but allows for the effects of ovalization of the pipe cross-section on the moment-curvature constitutive behaviour of the pipe. It is shown that the results using DYNA3D are in good agreement with both experimental data and the e-p-h-s model predictions and confirms the accuracy of the latter. While the DYNA3D study is not exhaustive, the localized shell bending deformation of whipping pipes in which ‘kinks’ are formed is reproduced with reasonable accuracy and it has permitted the effect of the strain-rate sensitivity of the yield stress of the pipe material to be examined in a preliminary manner.

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Fang, Yang, Li, Tan, Wang, and Du. "Experimental and Numerical Study on Mechanical Analysis of Buried Corroded Concrete Pipes under Static Traffic Loads." Applied Sciences 9, no. 23 (November 20, 2019): 5002. http://dx.doi.org/10.3390/app9235002.

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Concrete pipes are widely used in municipal drainage projects. Corrosion is a common issue affecting concrete pipes, causing leakage of pipes, environmental pollution, and road collapse. It is necessary to study the mechanical properties of corroded concrete pipes. To investigate in depth the influence of corrosion depths, corrosion widths, traffic loads, and cover depths, on mechanical characteristics of buried corroded concrete pipes under static traffic loads, a series of full-scale tests were carried out. Then, a three-dimensional finite element model of buried corroded concrete pipes under traffic loads is established based on ABAQUS. Results showed that the inside of the pipe wall is more vulnerable to damage than the outside. The stress and strain of a corroded pipe is significantly larger than that of an uncorroded pipeline. The corrosion has a great influence on the stress and strain of the corroded area. The maximum principal stress and circumferential strain at corroded area increase with increasing of corrosion depth. The stress and strain first increases rapidly (0–10°), and then decreases rapidly (10–45°), then finally decreases slowly (45–180°) with an increase of corrosion width. In addition, the greater cover depth or increasing traffic load causes a rapid increase in both circumferential strain and the maximum principal stress.

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20

Robert, D. J., P. Rajeev, J. Kodikara, and B. Rajani. "Equation to predict maximum pipe stress incorporating internal and external loadings on buried pipes." Canadian Geotechnical Journal 53, no. 8 (August 2016): 1315–31. http://dx.doi.org/10.1139/cgj-2015-0500.

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Pipelines used for water and other services are very important lifelines in modern society. Commonly, these buried pipes are subjected to significant stresses due to external (traffic and earth) and internal (water pressure) loads. As many of these pipelines were laid sometime in the last century or earlier, in most cases their condition has deteriorated primarily by electrochemical and (or) microbiological corrosion. Corrosion activity (internal and external) can manifest in various forms, but in many cases will lead to reduced pipe thickness, which in turn leads to an increase in pipe stresses induced by the external and internal loads. Currently available analytical procedures to estimate pipe stresses are based on oversimplifications such as the two-dimensional (2-D) analysis based on Winkler springs, limiting their application to general pipe burial conditions. This paper describes the application of a three-dimensional (3-D) finite element method to analyse a buried pipe subjected to external and internal loads. Firstly, the finite element model is validated against the data from field tests conducted on the basis of a cast iron pipe that was laid in 1930 at Strathfield, Sydney, Australia. The results of these 3-D finite element analyses are then used to develop a closed-form expression to predict maximum stresses in pipes of different sizes buried in different soil types. Having obtained a good agreement between the proposed model outcomes and the 3-D finite element analysis results, the proposed model has been validated against the field test data under different internal and external loadings. The verified outcomes of the model reveal that it can be used to predict maximum stresses without conducting a full-scale finite element analysis, which often requires specific computational resources and computational skills. Furthermore, the proposed model can be used in probabilistic analyses, where a large number of calculations need to be carried out to account for the uncertainty of the input variables. The applications of the model are also discussed in relation to the assessment of pipe performance and remaining safe life.

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Hassan, Dyaa. "Protecting buried pipelines using different shapes of geofoam blocks." Mining of Mineral Deposits 15, no. 2 (2021): 54–62. http://dx.doi.org/10.33271/mining15.02.054.

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Purpose. This research presents experimental modeling and numerical analysis on reducing stress and protecting buried pipelines using three arrangements techniques of expanded polystyrene (EPS) geofoam blocks: embankment, EPS block embracing the upper part of the pipe and EPS blocks as two posts and a beam. Methods. An experimental model consisted of steel tank with boundaries dimensions depending on the diameter of the pipe located at the center of it. The backfill on the pipe was made from sand and embedded EPS blocks with two techniques: EPS block embracing the upper part of the pipe and EPS blocks form two posts and a beam. Series of experiments were carried out using static loading on rigid steel plate to measure the pipe deformations and strains, as well as backfill surface displacement. The numerical analysis was used to simulate the experimental model using the finite element software program PLAXIS-3D. Findings. The results reveal that the most effective method which prevents stress on the buried flexible pipe was EPS post and beam system followed by EPS embracing the upper part of the pipe. The results obtained from the numerical analysis and the experiment demonstrate the same trend. The parametric study shows that EPS post and beam blocks model has higher surface displacement than embracing the upper part of the pipe model, which is more effective in case of high rigidity of the pipe. Originality. Reducing stress on buried pipes using different geofoam shapes to find which one is the optimum method. Practical implications. Two configurations of EPS geofoam blocks – EPS block embracing the upper part of the pipe and EPS blocks post and beam system - ensure successful stress reduction and protect buried pipes

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Liu, Yu Liang, Fei Wang, Lin Ping Li, and Guo Wei Wang. "Numerical Analysis of Buried Heating Branch Junctions." Applied Mechanics and Materials 721 (December 2014): 393–96. http://dx.doi.org/10.4028/www.scientific.net/amm.721.393.

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In this paper, the tee of buried heating pipe network has been investigated via the elastic-plastic finite element method. Fourth equivalent stress and distribution regularity of buried heating tees have been analyzed at different branch pipe diameter d/D and different branches length. The obtained results show that the limit length of tees decreases for the pipe diameter above DN500. The smaller diameter can lower the Von Mises stress of tees effectively. The stress of the outer wall is always greater than the internal stress.

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Khademi-Zahedi, Reza, and Pouyan Alimouri. "Finite Element Analysis to the Effect of Thermo-Mechanical Loads on Stress Distribution in Buried Polyethylene Gas Pipes Jointed by Electrofusion Sockets, Repaired by PE Patches." Energies 11, no. 10 (October 19, 2018): 2818. http://dx.doi.org/10.3390/en11102818.

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Polyethylene (PE) gas pipes can be jointed together by electrofusion PE fittings, which have sockets that are fused onto the pipe. Additionally, electrofused PE patches can be used to repair defected pipes. When these pipelines are buried under the ground, they can experience sever local stresses due to the presence of pipe joints, which is superimposed on the other effects including the soil-structure interaction, traffic load, soil’s column weight, a uniform internal pressure, and thermal loads imposed by daily and/or seasonal temperature changes. The present contribution includes two cases. At first, stress variations in buried polyethylene gas pipe and its socket due to the aforementioned loading condition is estimated using finite element. The pipe is assumed to be made of PE80 material and its jointing socket material is PE100. Afterward, the effects of aforementioned thermo-mechanical loads on the stress distribution in patch repaired buried pipes are well investigated. The soil physical properties and the underground polyethylene pipe installation method are based on the American association of state highway and transportation officials and American society for testing and material standards. The computer simulation and analysis of stresses are performed through the finite element package of ANSYS Software. Stress concentrations can be observed in both components due to the presence of the socket or the repair patch. According to the results, the electrofusion sockets can be used for joining PE gas pipes even in hot climate areas. The maximum values of these stresses happen to be in the pipe. Also, the PE100 socket is more sensitive to a temperature drop. Additionally, all four studied patch arrangements show significant reinforcing effects on the defected section of the buried PE gas pipe to withstand applied loads. Meanwhile, the defected buried medium density polyethylene (MDPE) gas pipe and its saddle fused patch can resist the imposed mechanical and thermal loads of +22 °C temperature increase.

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Xue, Feng Mei, Fu Guo Li, Jiang Li, Wen Jun Yu, and Jian Fei Li. "Fracture Analysis of Pipe Sleeve on Extrusion Flare-Less Pipe Joints for Aircraft Hydraulic Pipe." Advanced Materials Research 291-294 (July 2011): 1087–90. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.1087.

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The forming process of aircraft hydraulic pipe joints is investigated through experiments and analyses to solve the cracking problem of pipe sleeve on extrusion flare-less pipe joints. It can be concluded that the internal cause of the fracture failure is connected with the content, shape and distribution of δ-ferrite in 0Cr12Mn5Ni4Mo3Al high strength stainless steel, and the external cause is associated with the bearing behavior in the extrusion-bulging process of pipe sleeve. The crack is formed in the criss-crossing section of δ-ferrite on the function of shear stress in the stress concentration position, which belongs to ductile deformed crack. It eventually induces the intergranular fracture of pipe sleeve along the long axis with the expanding of subsequent crack.

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Li, Na, and Jing Ji. "Mechanics Analysis and Construction Measures on Tension-Chord Beam Architecture." Applied Mechanics and Materials 368-370 (August 2013): 1535–38. http://dx.doi.org/10.4028/www.scientific.net/amm.368-370.1535.

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In order to acquire mechanic performance of tension-chord Beam structure and the interaction between column and soil for canopy structure, combined with its own particularity pipe-soil ANSYS nonlinear analysis was carried out by using DP model, and from buried depth of pipe variation law of deformation, shear stress and equivalent stress for surrounding soil was investigated. The results show that the vertical stress is the bigger than horizontal stress and local stress of soil under pipe is larger, so this phenomenon is regarded as the stress concentration. Flexible connecting of column bottom can realize movement and recombination of structure, and pipe-soil radius and construction measures can provide safe and reliable reference for design and construction of mobile greenhouse structure.

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Mahardhika, Pekik, Adi Wirawan Husodo, George Endri Kusuma, Raden Dimas Endro Witjonarko, and Ekky Nur Budiyanto. "Analysis of Symmetrical and Nonsymmetrical Vertical Expansion Loop to Increase Flexibility And Reduce Pipe Stress Based On ASME B31.3." TEKNIK 42, no. 1 (May 3, 2021): 63–70. http://dx.doi.org/10.14710/teknik.v42i1.29244.

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Thepiping system is a medium used to convey, distribute, mix, separate, discharge, meter, control or snub fluid flows, and transmit a fluid pressure. The piping system design will have stresses due to thermal and pressure effect. The thermal effect induce pipe expansion. The pipe expansion affect to pipe flexibility, so it is necessary to design an expansion loop. Expansion loop is a method used to increase flexibility in piping systems. This article aims to analyze symmetrical and non-symmetrical in vertical expansion loops whether it can increase flexibility and reduce pipe stress. This article conducts an expansion loop design with 3 trials, namely trial 1 (Vertical Expansion Loop), trial 2 (Nonsymmetrical Vertical Expansion Loop 1), and trial 3 (Nonsymmetrical Vertical Expansion Loop 2). The three trials were compared for flexibility and stress values based on ASME B31.3 requirements. The study results show that all trial 1, trial 2, and trial 3 have good flexibility with a value of 0.00016 because not exceed the requirements of ASME B31.3. The highest design code stress value in trial 1 is 5955 psi (Node A07F), trial 2 is 5906 psi (Node A05F), and trial 3 is 5906 psi (Node A06N). All trials have a code stress not exceeding the allowable stress (20000 psi). So that the symmetrical or nonsymmetrical design of the vertical expansion loop can both increase flexibility and reduce pipe stress.

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Lu, Cai Hong, Yong Gang Liu, Xin Hu Wang, Fang Po Li, and Ting Ting Qu. "Failure Analysis of Fractured S135 Grade Drill Pipe." Applied Mechanics and Materials 431 (October 2013): 69–74. http://dx.doi.org/10.4028/www.scientific.net/amm.431.69.

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The fractured drill pipe was investigated by means of non-destructive testing, chemical composition analysis, optical microscope, material property testing machine and SEM with EDS. The results showed that fracture of drill pipe body was hydrogen sulfide stress corrosion cracking. High strength, high hardness, and stress corrosion sensitivity of the drill pipe material were important reasons leading to failure.

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Liu, Xin, Yanming Zhang, Qun Liu, Xu Sun, Yu Wang, and Liye Zhao. "Analysis of abnormal expansion of pipe system and optimization of structural stress in 350MW unit." E3S Web of Conferences 261 (2021): 02073. http://dx.doi.org/10.1051/e3sconf/202126102073.

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A 350MW power plant main steam and reheat hot steam pipe subsidence occurred in part of the pipe section, through field inspection, calculation and checking analysis, combined with pipeline support and hanger adjustment, load testing and elevation measurement and other means, the settlement of the pipe system to optimize the overall stress state of the pipe system. Through the thermal displacement of the pipe system support lifting point, the selection and calculation of the pipe system support hanger and the overall design state stress check of the pipe system, the design state is basically consistent with the check state. Through to the key node load tests have shown that small spring hanger selection is the primary cause of section settling, combined with the spring adjustment space and calculation results are part of the hanger. Finally, the settlement of pipeline is realized, main steam pipe at the same time a stress and secondary stress were achieved about 15% of the decline, piping stress has been further optimized.

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Li, Fa Gen, Bin Wei, Zhen Quan Bai, and Xue Hui Zhao. "Performance Analysis on CRA-Clad Pipes Extruded from Bimetallic Centrifugal Castings." Advanced Materials Research 287-290 (July 2011): 2288–93. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.2288.

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Recently a new method for manufacturing bimetal clad pipes is introduced, which can integrate centrifugal casting with extrusion technology organically. Through experimental study on microstructure and properties of bimetallic clad pipes manufactured by centrifugal casting and extruding, the results indicates that bimetal clad pipes with intact metallurgical interface have good bonding properties. Meanwhile wider interfacial zone will be favorable for reducing deformation stress. However there are still a few technical difficulties about the bimetallic clad pipe. Due to chemical composition and properties difference between backing materials and CRA layer, chemical elements will spread and microstructure will change during the process of production and even mechanical behavior of backing metal pipe and corrosion resistance of CRA layer will decline. To meet application requirements, appropriate heat treatment with bimetal clad pipes seems vita.

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Belyamna, Mohammed Amine, Abdelmoumene Guedri, and Racim Boutelidja. "Reliability Analysis of a Pre-Cracked Structure in Accidental Operation Conditions." Key Engineering Materials 820 (September 2019): 188–202. http://dx.doi.org/10.4028/www.scientific.net/kem.820.188.

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Evaluating the integrity of a structure consists in proving its ability to realize its mechanical functions for all modes of loading, normal or accidental, and throughout its lifetime. In the context of nuclear safety, the most important structures consider the presence of a degradation grouping several aspects, such as cracks. In this context, the fracture mechanics provide the tools needed to analyze cracked components. Its purpose is to establish break criteria for judging loading margins in normal or accidental operating conditions. The seismic load is one of the dominant loads for the failure assessment of the pipes. Its probabilistic dispersion, however, was not taken into account in the past probabilistic fracture mechanics analysis. The objective of this paper is to simulate and analyze the effect of abnormal stress on the reliability of tow pipe sizes. As result the seismic stress has more effect on the break probability, but not for the leak probability. In the case without a seismic load, the break probability is mainly dominated by an initial crack size. The earthquake has much effect on the break probability for the large diameter pipe, not for the small diameter pipe. In the large diameter pipe, the break probability increases gradually with the time. The leak probability of both pipe sizes is not affected by the seismic curve.

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Govindaraj, P., and Mouleeswaran Senthilkumar. "Performance Analysis of Thin Shell Bends under High Pressure and Temperature." Applied Mechanics and Materials 787 (August 2015): 296–300. http://dx.doi.org/10.4028/www.scientific.net/amm.787.296.

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Around 70% of the cost in piping industry is spent in the pipe manufacturing with optimum design of pipes without defects. Research on design of pipes has gained importance from the last decade. There are numerous methods being developed to improve the efficiency of piping units considering various parameters. The pipe tends to flatten when they are forced to bend, this geometrical changes has a significant role in the acceptability criteria of pipes. It is necessary to bend pipes in order to transmit liquid or gas from one place to other place. In this work special attention is given to pipe bends because of high stress concentration due to various loading conditions. From several kinds of piping systems, process piping systems are chosen for analysis since pipes used here transport important and hazardous materials. Damage to such piping system can cause serious loss to economy and human lives. The geometrical imperfection associated with bending of pipes is ovality. This degree of ovality determines the acceptance of pipes. Thickening and thinning effects cause additional problems like large plastic deformation and loss of flexibility respectively. Hence estimation of the best degree of ovality is required. In this work effect of ovality is estimated by taking the internal fluid pressure and In plane bending moment into account.

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Harte, A. M., and J. F. McNamara. "Modeling Procedures for the Stress Analysis of Flexible Pipe Cross Sections." Journal of Offshore Mechanics and Arctic Engineering 115, no. 1 (February 1, 1993): 46–51. http://dx.doi.org/10.1115/1.2920088.

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Thick tube theory is incorporated into an existing analytical model for the three-dimensional analysis of bonded flexible pipe cross sections under offshore loading conditions. The original model considers material layers as isotropic/orthotopic thin tubes, and layers of helically wound reinforcing cables are modeled separately. The improvement in the results obtained with the incorporation of the new thick tube layer is demonstrated for a flexible pipe with D/t = 10. The finite element technique has also been used to model this type of pipe structure. Pipe sections are discretized using axisymmetric elements for the tube-type layers and special discrete reinforcement elements for the helical cables. A particular example of a three-layer doubly reinforced pipe section under internal pressure is studied. Good agreement is found between analytical model and finite element results for all the main deformation and stress quantities including cable stresses.

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Chen, Mei Bao, Yu Rong Jiang, Yuan Tian, Chun Bi Xu, and Zhi Yong Cai. "Integrity Assessment on Natural Gas Transmitting Pipe Based on the Finite Element Analysis." Advanced Materials Research 652-654 (January 2013): 1345–48. http://dx.doi.org/10.4028/www.scientific.net/amr.652-654.1345.

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Recently, the intelligent inspection data of one natural gas transmitting pipeline showed that lots of the blistering was found in the pipe inner surface. In this paper, the method of finite element analysis was carried out to simulate and calculate the effect of blistering to the pipe strength. The results show that the max vonmises stress of the pipe with blistering was close to the yield strength and the max vonmises stress of the pipe increased with the increase of the press in the blistering. The minimum safety factor in the pipe with blistering was 0.99 which was reduced by the blistering. The sulfide stress corrosion (SSCC) and the manufacturing technology of hot rolling compound accelerated the growth of the blistering in the pipe.

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Mohamadi, Milad, and Mahmood Heshmati. "Failure analysis of glass-reinforced polyester mortar pipes with different cores subjected to combined loading." Journal of Sandwich Structures & Materials 21, no. 8 (July 20, 2017): 2616–53. http://dx.doi.org/10.1177/1099636217720214.

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In this paper, the failure of glass-reinforced polyester mortar pipes with different cores subjected to pure and combined loading are analyzed. To enhance the stiffness of fiber-reinforced polyester pipe, filler layer is incorporated in between fiber-reinforced polyester plies. Thus, in this study, new nanocomposite materials are proposed as a core layer in the glass-reinforced polyester mortar pipes. The performance of the pipes in the presence of nanosilica/resin, nanosilica/fiberglass/resin and multi-walled carbon nanotubes (MWCNTs)/resin and sand/resin cores are investigated. Finite element method is used to analyze the effects of extensive design parameters on the first ply failure and functional failure of glass-reinforced polyester mortar pipes. Maximum normal stress, Tsai–Wu and Tsai–Hill criteria are employed for the failure analysis. Two end boundary conditions are considered in the simulations. The effects of core material constituents, core thickness, filament winding angle and lay-up configurations, layers thicknesses and pipe radius are investigated. The results are also obtained under pure and combined loading conditions. The stress concentration around circular and rectangular holes in glass-reinforced polyester mortar pipes with sand/resin core is also studied. Accordingly, the stress concentration factors are reported for each case. Detailed discussions are done and brief design guidelines are given.

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YAKUBOVSKAYA, S. V., N. I. KRASOVSKAYA, and N. Y. SILNITSKAIA. "SIMULATION OF THE STRESS-STRAIN STATE FOR LONG-LENGTH FLEXIBLE PIPES." Periódico Tchê Química 15, no. 30 (August 20, 2018): 670–77. http://dx.doi.org/10.52571/ptq.v15.n30.2018.674_periodico30_pgs_670_677.pdf.

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An algorithm for calculating the stress-strain state for a system of long-length flexible pipes on a drum is proposed. The material which the pipe is made of operates in the area of plastic deformation due to the relative small drum diameter. To take into account the nonlinear properties of the construction material, the concept of a variable (secant) module is used. The algorithm for calculating the stress-strain state of a flexible reinforced long-length pipe was compiled on the basis of the iteration method in terms of the magnitude of the change in the secant modulus. A block diagram is given. Numerical results of the stress analysis of a flexible pipe made of reinforced polyethylene are presented in the form of graphs and tables.

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Hyde, T. H., W. Sun, and A. A. Becker. "Use of life and strain fraction rules for creep life prediction of pressurized pipe components undergoing geometry change." Journal of Strain Analysis for Engineering Design 40, no. 4 (May 1, 2005): 385–94. http://dx.doi.org/10.1243/030932405x16007.

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The results of creep failure life predictions of pressurized plain pipes, pipe bends, and a thick-walled pipe with a circumferential weld are used to demonstrate the applicability of a stress-based life fraction rule (LFR) and a strain-based strain fraction rule (SFR), under conditions of geometric non-linearity (GNL). The material properties used are related to a CrMoV pipe, at 640°C. Both the LFR and the SFR predictions are based on the stress and strain solutions obtained from the finite element calculations using a Norton creep law. The results obtained were compared with those obtained from corresponding creep damage analyses. For the cases investigated, it has been shown that, compared with damage results, conservative failure lives with consistent failure positions were obtained for the pipe weld, using both the LFR and the SFR methods. For plain pipes and pipe bends, the SFR prediction produces conservative results. However, the LFR prediction overestimates the failure life for the range of pipe diameter ratios investigated. The results obtained indicate that the LFR and SFR methods have potential for predicting creep failure lives in cases when the effect of geometry change is significant and hence the method based on the steady state peak stresses obtained from small deformation analysis is not applicable.

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You, Ri, and Hong Bo Gong. "Failure Analysis of PCCP with Broken Wires." Applied Mechanics and Materials 193-194 (August 2012): 855–58. http://dx.doi.org/10.4028/www.scientific.net/amm.193-194.855.

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The prestressing wires of prestressed concrete cylinder pipe (PCCP) provide pipe wall with compressive stress to resist internal pressure. Broken wires resulting from corrosion is a major factor contributing to the degradation of pipe strength. In order to analysis the failure process of PCCP with broken wires, a 3-D model with a very fine mesh is developed for the pipe structure, considering material nonlinear behavior, pipe-earth interaction, prestress loss, and combined effects of external and internal loads. The results of nonlinear finite element analysis show that wire breaks causing prestress loss can accelerate the failure process of PCCP. As internal pressure increases, the earliest concrete cracking and steel-cylinder yielding occurs in the prestress loss zone. The closer to the prestress loss zone, the higher stress unbroken wires will have.

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Li, Pan Wu, and Qian Qian Si. "The Design of Cooling Water Pipe and Cooling Analysis in Mass Concrete." Advanced Materials Research 255-260 (May 2011): 3510–13. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.3510.

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Inconstruction process of mass concrete is apt to form excessive temperature stress and cause mass concrete cracking, because of its high inner temperature, big internal and external temperature difference. In order to prevent their cracking, in mass concrete of the internal Settings with cooling water pipe cooling is one of the commonly used massive concrete construction method. This paper presents a massive concrete design of cooling water cooling and calculation theory, based on the cooling pipes in concrete heat transfer performance, through the cooling water pipe and concrete heat exchange principle.

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Ahn, Moktan, and Joonhong Park. "Relationship between shear strength and surface roughness of double-layered pipes by cold drawing." Mechanical Sciences 12, no. 1 (February 9, 2021): 123–31. http://dx.doi.org/10.5194/ms-12-123-2021.

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Abstract. Pipes applied to marine plants are used in deep-sea environments; therefore, they must be resistant to high pressure and corrosion. Because it is difficult to satisfy both of these factors in a single pipe, studies on a double-layered pipe are continuously being performed. An outer pipe should be made of carbon steel, with high pressure resistance, and an inner pipe should be made of stainless steel, with high corrosion resistance. A pipe formed by combining these two pipes is called a lined pipe. The shear strength of the lined pipe is an important factor because pipe cracking can occur due to stress concentration when two pipes are separated by bending or high pressure. Therefore, various processes have been applied to increase the shear strength. In this paper, we investigate the effect of the surface roughness of the bonding interface on the shear strength. Surface roughness is in units of micrometers, and it cannot be used for finite element method (FEM) analysis. Therefore, surface roughness should be converted into a friction coefficient to perform FEM analysis. The effect of surface roughness on shear strength was studied in the relationship between the results of pressure from FEM analysis and the shear strength test.

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Wang, Bin, Cai Liu, Xue Li Wu, and Xue Fei Qiao. "The Stress Analysis of New Pressure Piping Model." Key Engineering Materials 474-476 (April 2011): 1215–20. http://dx.doi.org/10.4028/www.scientific.net/kem.474-476.1215.

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High-pressure becomes the high pressure unit design main consideration factor to compressive load capacity, security, efficiency, economic and manufacturing process of high-pressure equipment. This article proposes a new pressure piping according to the current high-voltage device development tendency and the future requirement. This new type of pressure pipe can be simplified for pipe casing model. Firstly we establish single, double and multilayer pressure piping model. We push out the multilayer pressure pipe stress formula according to stress situation of the analysis of the knowledge of mechanics of each model. We get this pressure piping withstand by the most intrinsic pressure enhance obviously under each layer within the radius of the cylinder reach the initial limitation of materials and other parameters of model are same through the comparison of the theoretical formula calculation with other general. Pressure pipeline calculated value. The multi-layer pressure piping system's circum radius are smaller than other piping with other pressure piping withstand the same most intrinsic pressure and the most interior radius are the same situation.

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Davoodi, Saman, and Amir Mostafapour. "Theorical Analysis of Leakage in High Pressure Pipe Using Acoustic Emission Method." Advanced Materials Research 445 (January 2012): 917–22. http://dx.doi.org/10.4028/www.scientific.net/amr.445.917.

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Leak detection is one of the most important problems in the oil and gas pipelines. Where it can lead to financial losses, severe human and environmental impacts. Acoustic emission test is a new technique for leak detection. Leakage in high pressure pipes creates stress waves resulting from localized loss of energy. Stress waves are transmitted through the pipe wall which will be recorded by using acoustic sensor or accelerometer installed on the pipe wall. Knowledge of how the pipe wall vibrates by acoustic emission resulting from leakage is a key parameter for leak detection and location. In this paper, modeling of pipe vibration caused by acoustic emission generated by escaping of fluid has been done. Donnells non linear theory for cylindrical shell is used to deriving of motion equation and simply supported boundary condition is considered. By using Galerkin method, the motion equation has been solved and a system of non linear equations with 6 degrees of freedom is obtained. To solve these equations, ODE tool of MATLAB software and Rung-Kuta numerical method is used and pipe wall radial displacement is obtained. For verification of this theory, acoustic emission test with continues leak source has been done. Vibration of wall pipe was recorded by using acoustic emission sensors. For better analysis, Fast Fourier Transform (FFT) was taken from theoretical and experimental results. By comparing the results, it is found that the range of frequencies which carried the most amount of energy is same which expresses the affectivity of the model.

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Han, Liang, Ai Jun Yao, and Jun Wei Han. "New Method and Application of Negative Friction Resistance Monitoring for PHC Pipe Pile." Advanced Materials Research 1065-1069 (December 2014): 138–42. http://dx.doi.org/10.4028/www.scientific.net/amr.1065-1069.138.

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The theoretical calculation of PHC pipe pile negative friction resistance is difficult to obtain valuable results due to many complex factors involved, such as soil properties, consolidation conditions and actual working environment, so the field monitoring is the only feasible method. The pile negative friction resistance can be got by pre-buried sensors inside the pile to monitor the changes of stress and strain of shaft. However, for PHC pipe pile, the sensors can not be embedded and protected effectively in the process of pile manufacturing, which makes the negative friction resistance of PHC pipe pile become a very thorny problem. Based on the improved field monitoring method and data analysis of sliding micrometer technology, a new method was introduced into the PHC pipe pile negative skin friction resistance testing in this paper. We can got not only the PHC pipe pile negative friction resistance, distribution range and neutral point position with different load or time, but also the strain distribution, axial force distribution, skin friction resistance and toe resistance distribution of pile, etc. The practical engineering application shows that the new method is very effective to monitor PHC pipe pile negative friction resistance and very beneficial to further research on formation mechanism and theoretical calculation of negative friction resistance of PHC pipe pile.

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Zhou, Yan, Yu Ran Fan, Deng Zun Yao, Ting Zhong, and Xi Xi Zhang. "Stress Analysis for the Tie-in Girth Weld of X90 Pipeline." Materials Science Forum 850 (March 2016): 889–93. http://dx.doi.org/10.4028/www.scientific.net/msf.850.889.

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Tie-in is a very important step on the final stage of pipe construction. The stress of the tie-in girth weld is really one of the key roles that affect the security of the pipeline in service. In this paper, Finite Element Method (FEM) was used to determine the stress of the tie-in girth weld. The factors of stress of tie-in girth weld were analyzed. The results show that uncovered pipe length, tie-in offset and misalignment were the important factors which affect the stress of tie-in girth weld. The maximum Mises stress and axial stress at tie-in girth weld increased with the uncovered pipe length decreasing and the tie-in offset increasing. The stress also increased significantly with girth weld misalignment, especially for axial stress.

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Liu, Yong Gang, Fang Po Li, Ding Peng Ye, and Xue Qing Teng. "Simulation on Stress Distribution of Drill Pipe’s Surface Initial Crack." Applied Mechanics and Materials 184-185 (June 2012): 460–64. http://dx.doi.org/10.4028/www.scientific.net/amm.184-185.460.

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Abstract: In drilling process, drill pipes’ out surface always have lots of pits and scratches due to the corrosive and erosion of mud or wear of well wall in work environment. Through establishing drill pipe’s working model and constitutive equations with Finite Element Analysis Software, the paper have simulated stress distribution on drill pipe body under two different condition that without mechanical damage and with initial crack. Analysis results show that the maximum stress increases with the increasing of initial crack depth, and the maximum stress position turns to crack circumferential root from the crack radial root with the increasing of initial crack’s depth. The analysis result is completely consistent with the actual morphology of crack propagation, as a result, the simulation analysis provides a effective new methods and reference for remaining life assessment and failure analysis of drill pipe.

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Xue, Jiang Wei, Yong Yang, Yi Zhao, and Xin Sheng Ge. "Three-Dimensional Analysis of the Partner of Laterally Loaded Variable Rigidity Pile (Pile Partner)." Applied Mechanics and Materials 256-259 (December 2012): 320–23. http://dx.doi.org/10.4028/www.scientific.net/amm.256-259.320.

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Concerning the stress and displacement of the partner under lateral load, reference on full-scale model tests on behavior of cast-in-place concrete pipe piles, two cases are analyzed by means of 3D finite element method, calculations show that in condition I, pile and cap rigid joint (pile foundation) plus partner, partner block the punching stress from pile top to cap continue to spread; and in condition II, the distance between pile top and pile cap is 200 mm, partner is in normal bending shear state; As the flexural rigidity of partner is much larger than the pile, if under earthquake or other rare action, partner may sacrifice firstly to keep pile perform well.

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Koch, R. L., E. F. Rybicki, and R. D. Strattan. "A Computational Temperature Analysis for Induction Heating of Welded Pipes." Journal of Engineering Materials and Technology 107, no. 2 (April 1, 1985): 148–53. http://dx.doi.org/10.1115/1.3225791.

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Recent approaches to controlling stress corrosion cracking in welded 304 stainless steel pipes have been based on various types of controlled heating procedures. When applied properly, the heating procedure introduces high compressive stresses in region of observed cracking. The compressive stresses are believed to be effective in deterring stress corrosion cracking. One procedure for applying controlled heating to the pipe employs induction heating and is called Induction Heating for Stress Improvement or IHSI. The effective utilization of induction heating requires an understanding of how the induction heating parameters are related to the resulting residual stresses. This paper describes the development of a computational model directed at evaluating the heat densities and temperature distributions for Induction Heating for Stress Improvement (IHSI). The basic mechanism of inducting differs from that of a welding arc in that induction heating produces a distribution of heat sources within the pipe wall while in weld arc heating, the heat source is confined to the surface. Thus the computational model requires two parts. The first part evaluates the induced electrical current and determines the density of heat sources in the pipe wall. The second part of the model uses these heating densities to evaluate the temperature distribution. Temperature dependent properties were found to be important in representing the induction heating phenomenon. However, including temperature dependent properties in the model leads to nonlinear equations which require iterative solution methods for each part of the model. The nonlinear characteristics of the equations also require iterations between the two parts of the model. The model includes the important parameters of the induction heating process and has shown good agreement with temperature data for two different pipe sizes. Because of the inherent nonlinearities in the model and the iterative methods required for general solutions, extensions of the model to improve the algorithimic efficiency are discussed.

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Khoramishad, Hadi, and Majid Reza Ayatollahi. "FINITE ELEMENT ANALYSIS OF A SEMI-ELLIPTICAL EXTERNAL CRACK IN A BURIED PIPE." Transactions of the Canadian Society for Mechanical Engineering 33, no. 3 (September 2009): 399–409. http://dx.doi.org/10.1139/tcsme-2009-0028.

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In this research, a buried pipe containing an external semi-elliptical crack has been modeled and investigated using finite element analysis. The interaction between the soil and pipe has been considered according to the Burns and Richard model. A few major parameters, namely, the soil height over pipe, the geometries of pipe and crack and the circumferential position of crack on pipe have been changed and their effects on elastic stress intensity factors have been studied at different positions along the crack front. The results showed that the crack experienced mixed mode loading condition and the circumferential crack position on pipe had a significant influence on the stress intensity factors.

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Choe, Jae-Seung, and Jin-Han Jeong. "Equivalent Mechanical Property for Stress Analysis on Lined Pipe." Transactions of the Korean Society of Mechanical Engineers A 26, no. 3 (March 1, 2002): 445–51. http://dx.doi.org/10.3795/ksme-a.2002.26.3.445.

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Puri, Anas. "Analisis Numerik Perkerasan Sistem Pelat Terpaku Tiang Tunggal menggunakan Tiang Pipa Baja pada Tanah Lunak." MEDIA KOMUNIKASI TEKNIK SIPIL 25, no. 2 (January 8, 2020): 171. http://dx.doi.org/10.14710/mkts.v25i2.19098.

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All of the full-scale tests and numerical analysis of Nailed-slab System from previous researchers used massive reinforced concrete piles. This research will study the possibility of steel pipe pile as a replacement of massive reinforced concrete piles if there are available enough steel pipe piles. This research is aimed to study the behavior of single steel pipe pile Nailed-slab System on soft clay and the influence of pile length due to slab deflection and soil stresses. It was used the data from Puri (2015a) for a single massive reinforced concrete pile Nailed-slab. This massive reinforced concrete pile was replaced by a single steel pipe pile with similar and varied diameter which analyzed by the 2D finite element method. Results show that the steel pipe pile can be used as a “nail” at the Nailed-slab pavement system but by a larger dimension compared to the massive reinforced concrete pile. The maximum effective shear stress in soil did not reach undrained shear strength under a standard wheel load 40 kN. Generally, the soil was not failure.

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Hutař, Pavel, Martin Ševčík, Ralf Lach, Zdeněk Knésl, Luboš Náhlík, and Wolfgang Grellman. "A Description of Local Material Properties Close to a Butt Weld." Key Engineering Materials 586 (September 2013): 146–49. http://dx.doi.org/10.4028/www.scientific.net/kem.586.146.

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The paper presents a methodology for the lifetime assessment of welded polymer pipes. A fracture mechanics analysis of a butt-welded joint is performed by simulating radial crack growth in the nonhomogenous region of the pipe weld. It was found that the presence of material nonhomogeneity in the pipe weld caused by the welding procedure leads to an increase in the stress intensity factor of the radial crack and changes the usual failure mode of the pipe system. This can lead to a significant reduction in the lifetime of the pipe system.

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Journal articles on the topic 'Pipe stress analysis'

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