scholarly journals Stress Calculations Adopted Finite Element Method of Pressure Steam Pipeline Containing Defects

2021 ◽  
Vol 353 ◽  
pp. 01003
Author(s):  
Yonggui Chen ◽  
Ping Tang ◽  
Jiang Zhong ◽  
Sunting Yan ◽  
Nanhui Jin ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Graphical User Interface ◽  
Safety Assessment ◽  
Film Stress ◽  
Program Code ◽  
Steam Pipeline ◽  
Carbon Neutrality ◽  
Pressure Steam ◽  
Key Factor ◽  
Efficient Program

The stress behavior of defects is the key factor in the safety assessment of pressure steam pipeline containing defects. For achieving carbon peaking and carbon neutrality, high-parameter pressure steam pipelines are widely designed in the recent years. It makes the safety assessment based on defect stresses become significantly important. A combined FEA method of stress calculations was proposed in the present study for calculating film stress and bend stress of defects located in a pressure steam pipeline from a certain power plant. An efficient program code with graphical user interface was designed to automatically generate FEA models of defect part pipelines. It is truly an innovative highlight of the present work attributed to convenient operation and outstanding efficiency. This paper provides an available way to obtain the stress state of defects in the safety assessment of pressure steam pipeline containing defects.

Finite Element Analysis of the Stress on Cylinder of the Fluidized Bed Reactor for Fast Pyrolysis

2011 ◽  
Vol 201-203 ◽  
pp. 660-663
Author(s):  
Qing Ruo Xie ◽  
Yi Sun ◽  
Li Wen Zheng ◽  
Hu Qi Wang ◽  
Zhang Fa Tong
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Fluidized Bed ◽  
Safety Assessment ◽  
Scale Up ◽  
Fast Pyrolysis ◽  
Fluidized Bed Reactor ◽  
Element Analysis ◽  
Ansys Analysis ◽  
Different Temperatures

A new experimental fluidized bed reactor was investigated and designed which has been widely utilized for fast pyrolysis under different temperatures (T=727–973 K).The stresses of the reactor cylinder are analyzed using finite element method(FEM, ANSYS Inc., U.S.A ) based on the safety assessment, and the cylinder is designed for installing scheme. The result of ANSYS analysis shows that the stress unstable positions are nearby both ends of the cylinder. The results of analysis are shown that the designing stresses are not beyond the allow able ones. So the designing parameters can possess sufficient reliability, and the design scheme can completely satisfy the strength requirement. Certainty of the stress could offered the valuable instruction for the application of the equipment on industrial scale-up.

scholarly journals Safety Assessment and Risk Management in Indian Building Construction Sites

2019 ◽  
Vol 8 (4S2) ◽  
pp. 8-12
Keyword(s):  
Safety Assessment ◽  
Building Construction ◽  
Construction Site ◽  
Construction Sites ◽  
Safety Measures ◽  
Severity Rating ◽  
Key Factor ◽  
Incident Rate ◽  
Observation Method ◽  
Unsafe Condition

Construction sites records high accident and incident rate due to lack of safety measures. Safety assessment rating is significant for every construction site to know safety status of the particular site. In this research TR safety observation method is used to assess the site performance. As unsafe condition is the key factor in every construction site, this research considers the possible unsafe conditions to assess the site performance. A questionnaire survey is done with the workers to know the existing safe conditions. Results showed that the safety performance of the site is 39%. Then every unsafe condition is ranked with respect to severity rating for detailed analysis. Furthermore bowtie analysis is used to identify the causes and consequences of the unsafe conditions. Through this analysis the owner can reduce the risk of every event and improve the site performance.

A Deployable Brace Model with Joint Clearance and Strut Eccentricity in Seismic Design

2019 ◽  
Vol 972 ◽  
pp. 123-128
Author(s):  
Ming Hao Hu ◽  
Pu Yang ◽  
Daniel McCrum
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Seismic Design ◽  
Joint Clearance ◽  
Lateral Stiffness ◽  
Practical Situation ◽  
Buckling Strength ◽  
Seismic Engineering ◽  
Deployable Structure ◽  
Key Factor

The paper discusses seismic performance of deployable brace member as well as its application in single-story single-bay frame by using finite element method in OpenSees Navigator. Even though deployable structure has wide applications in engineering area, it is almost blank for earthquake (seismic) engineering. A finite element deployable brace model consisting two identical struts and a revolute joint is built in this paper. The model considers joint clearance and initial eccentricity to accord practical situation. Hysteresis analysis has been done on the brace model as well as its application. The results show deployable structure provides sufficient lateral stiffness and ductility. Strut eccentricity is the key factor affecting the capacity of the strut and buckling strength, while joint clearance also has influence on the strut capacity and energy dissipation.

Analyses of Axisymmetric Sheet Forming Processes by Rigid-Viscoplastic Finite Element Method

1987 ◽  
Vol 109 (4) ◽  
pp. 347-354 ◽  
Author(s):  
J. J. Park ◽  
S. I. Oh ◽  
T. Altan
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Strain Rate ◽  
Rate Sensitivity ◽  
Sheet Forming ◽  
Flow Rule ◽  
Pressure Curve ◽  
Analytical Prediction ◽  
Key Factor ◽  
Element Method

Two types of sheet forming processes are analyzed by rigid-viscoplastic FEM (Finite Element Method): axisymmetric punch stretching and hydrostatic bulge forming. The present formulations, based on the membrane theory and the Hill’s anisotropic flow rule, include the rate sensitivity which is a key factor in controlling the forming of superplastic materials. Normal anisotropy is taken into account and Coulomb friction is assumed at the interface between punch and sheet. Nonsteady-state deformation processes, investigated in this study, were quasi-statically and incrementally analyzed. An FEM code was developed, using two-node linear elements with two degrees of freedom at each node, and applied to solve four categories of problems: (1) A.K. steel punch stretching, (2) hydrostatic bulging of a rate-insensitive material, (3) hydrostatic bulging of rate-sensitive materials, and (4) hydrostatic bulging of a superplastic material (Ti-6-4). Strain distributions and shape changes predicted in the first two problems were compared with experiments and results of other analyses. The results of the third problem could not be compared with experiments; however, the results showed that the rate sensitivity affects the deformation as expected. The fourth problem is the main theme of this paper. To maintain the superplasticity in forming processes and to produce sound products, the control of the strain-rate is a key factor. A hydrostatic bulge forming process, which is often used for manufacturing structural aerospace parts, was analyzed and discussed. Further, an optimum pressure curve (pressure versus time), which maintains the desired strain-rate in the deformed material, was obtained and compared with the results of an analytical prediction, available in the literature.

scholarly journals Numerical analysis of thermal stresses in welded joint smade of steels X20 and X22

2014 ◽  
Vol 18 (suppl.1) ◽  
pp. 121-126 ◽  
Author(s):  
Sasa Mladenovic ◽  
Vera Sijacki-Zeravcic ◽  
Gordana Bakic ◽  
Jasmina Lozanovic-Sajic ◽  
Marko Rakin ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Finite Element Method ◽  
Thermal Stresses ◽  
Welded Joint ◽  
Dissimilar Materials ◽  
Post Weld Heat Treatment ◽  
The Finite Element Method ◽  
Steam Pipeline ◽  
Transition Piece ◽  
Critical Regions

Stress calculation of steam pipeline is presented, focused on the welded joint. Numerical calculation was performed using the finite element method to obtain stress distribution in the welded joint made while replacing the valve chamber. Dissimilar materials were used, namely steel 10CrMoV9-10 according to EN 10216-2 for the valve chamber, the rest of steam pipeline was steel X20, whereas the transition piece material was steel X22. Residual stresses were calculated, in addition to design stresses, indicating critical regions and necessity for post-weld heat treatment.

Study on Nylon Cutting Properties Based on Cutting Temperature with Material Properties in Manufacturing System

2012 ◽  
Vol 252 ◽  
pp. 319-322 ◽  
Author(s):  
Ning Fan ◽  
Pei Quan Guo ◽  
Xiu Li Fu
Keyword(s):  
Finite Element Method ◽  
Material Properties ◽  
Manufacturing System ◽  
Cutting Tool ◽  
Cutting Temperature ◽  
Cutting Parameters ◽  
Rake Angle ◽  
Workpiece Surface ◽  
Key Factor ◽  
On Chip

In nylon material manufacturing process, cutting temperature is key factor to nylon cutting properties. The glass transition temperature should be regarded as criteria for determining proper cutting parameters. The cutting temperatures variation of workpiece and chip with time under different rake angles are calculated by finite element method. It is shown that cutting temperature on workpiece surface is higher than that on chip and decreases quickly. The rake angle of cutting tool has great effects on workpiece cutting temperature. Thus the rake angle should be rationally selected to guarantee quality for manufacturing system.

Stress of Make-Up Torque on the Gas Storage Well Bore and Coupling Connecting Thread

2013 ◽  
Vol 43 (3) ◽  
pp. 33-42 ◽  
Author(s):  
Peiqi Liu ◽  
Liming Zhang ◽  
Siyuan Xu ◽  
Zhixiang Duan ◽  
Zuzhi Chen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Finite Element Method ◽  
Finite Element ◽  
Stress Distribution ◽  
Fatigue Failure ◽  
Maximum Stress ◽  
Gas Storage ◽  
Well Bore ◽  
Key Factor ◽  
External Coupling

Abstract The structure of wellbore and coupling is connected by thread, it is the position where fatigue failure accidents are happened in gas storage well, and the make-up torque of thread is the key factor that influences the mechanical properties of this structure. In this pa- per, a finite element method was established to discuss the calculation method of make-up torque and the influence law on the stress of coupling in the gas storage well. Results show that the make-up torque cannot be simply ignored due to its great impact on internal stress distribution of gas storage well. Experimental results showed the correctness of the model. Under the action of the make-up torque, the overall stress level inside the wellbore is higher than the external coupling. However the maximum stress exists in the external coupling. The overall stress grad- ually increases with the increase of interference rotation number (abbr. RN) between coupling and wellbore, but the overall distribution trend is almost the same. The first thread on the left of the connection part is the area where fatigue failure is most likely to occur. The make-up torque between threads increases linearly with the increase of RN between cou- pling and wellbore.

Effect of Load Frequency on Dynamic Similitude of Scaled Model

2013 ◽  
Vol 448-453 ◽  
pp. 3508-3513
Author(s):  
Yu Chao Song ◽  
Yan Nian Cai ◽  
Chao Ming Huang ◽  
Hong Liang Yu
Keyword(s):  
Finite Element Method ◽  
Scaled Model ◽  
Test Analysis ◽  
Modal Theory ◽  
Load Frequency ◽  
Model Dynamics ◽  
Prototype Structure ◽  
Key Factor ◽  
Dynamic Similitude ◽  
Model Structures

The similitude requirement of excited load was deduced to maintain the consistent vibration between scaled model and prototype structure, based on the modal theory of multi-DOFs systems. The similitude of load frequency was another demand to maintain the consistent vibration, with the similitude of structure size and load magnitude. The dynamic similitude problem of a liquid tank was studied by finite element method and test analysis respectively. The results show that the similitude of load frequency is the insurance for the consistency of prototype and scaled model structures vibration. In a case the magnitude error of displacement is 8% to 10%, and the displacement and acceleration have all changed distinctly without the similitude of load frequency. All the results indicate that the similitude of load frequency is the key factor to analyze the scaled model dynamics correctly.

Analysis on the Hydroplaning of Aircraft Tire

2009 ◽  
Vol 87-88 ◽  
pp. 1-6 ◽  
Author(s):  
You Shan Wang ◽  
Jian Wu ◽  
Ben Long Su
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Element Model ◽  
Tire Model ◽  
Inflation Pressure ◽  
Civil Aircraft ◽  
Key Factor ◽  
Lagrangian Finite Element ◽  
Patterned Tire ◽  
Volume Method

Aircraft tire is an important subassembly of aircraft, which is related to its safety tightly, especially for civil aircraft. Moreover, hydroplaning of aircraft tires is often a contributing factor in take-off and landing overrun and veeroff accidents. Therefore the study on them is imperative. For studying the hydroplaning of aircraft tire, a 2D finite element model of aircraft tire is developed by using TYABAS software, and then a 3D patterned tire model is presented. The hydroplaning of aircraft tire is analyzed by generally coupling an Eulerian finite volume method and an explicit Lagrangian finite element method. The hydroplaning speeds are investigated, which is a key factor of hydroplaning. Results indicated that the hydroplaning speed increases with the increment of inflation pressure; the hydroplaning speed decreases with the increment of the footprint aspect ratio.

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