Flexibility Factors and Stress Indices for Piping Components With D/T ≧ 100 Subjected to In-Plane or Out-of-Plane Moment

1988 ◽  
Vol 110 (4) ◽  
pp. 374-386 ◽  
Author(s):  
T. Fujimoto ◽  
T. Soh
Keyword(s):  
Finite Element ◽  
Wall Thickness ◽  
Large Diameter ◽  
Thin Wall ◽  
Finite Element Analyses ◽  
Empirical Formulas ◽  
Stress Evaluation ◽  
Stress Indices ◽  
Piping Systems ◽  
Out Of Plane

The finite element analyses are carried out for the several piping components (D/T ≧ 100) subjected to in-plane or out-of-plane moment. For the stress evaluation of the chemical plant piping systems, ANSI B31.3 is usually applied. But the stress intensification factors and flexibility factors in this code are mainly for a heavy-wall-thickness pipe, so it is necessary to reconsider these factors for a thin-wall-thickness pipe with a large diameter. In our study, several finite element analyses using MSC/NASTRAN program were performed on the pipe bends (elbow or miter bend, 0.01 ≦ h ≦ 0.2) and the unreinforced fabricated tees (50 ≦ D/Tr ≦ 300, 0.5 ≦ d/D ≦ 0.95, 0.25 ≦ Tb/Tr ≦ 0.95), and the empirical formulas for the flexibility factors and the stress indices, due to out-of-plane or in-plane moment, were proposed. Experimental stress analyses for the piping components with D/Tr = 127 were also carried out, and it was confirmed that the results agreed well with the numerical ones.

Stress Analysis and Stress Index Development for a Trunnion Pipe Support

1982 ◽  
Vol 104 (2) ◽  
pp. 73-78
Author(s):  
M. H. Sadd ◽  
R. R. Avent
Keyword(s):  
Finite Element ◽  
Internal Pressure ◽  
Stress Analysis ◽  
Wall Thickness ◽  
Pressure Vessel ◽  
Stress Index ◽  
Secondary Stress ◽  
Empirical Formulas ◽  
Stress Indices ◽  
Finite Element Stress Analysis

A finite element stress analysis is presented of a trunnion pipe anchor. The structure is analyzed for the case of internal pressure and various end moment loadings. Stress results were post-processed and decomposed into average and linear varying (through the wall thickness). These decomposed values were then interpreted within the ASME Boiler and Pressure Vessel Code to estimate primary and secondary stress indices. Several computer runs were made for a variety of structural sizes and empirical formulas were developed expressing the stress indices as a function of certain dimensionless ratios.

Steel Sheet Shear Walls with Burring Holes for Low- to Mid-Rise Housings

2019 ◽  
Author(s):  
Yoshimichi Kawai ◽  
Shigeaki Tohnai ◽  
Shinichiro Hashimoto ◽  
Atsushi Sato ◽  
Tetsuro Ono
Keyword(s):  
Finite Element ◽  
Shear Stress ◽  
Large Deformation ◽  
Deformation Behavior ◽  
Steel Sheet ◽  
Shear Walls ◽  
Shear Load ◽  
Finite Element Analyses ◽  
Plane Shear ◽  
Out Of Plane

<p>Steel sheet shear walls with cold formed edge stiffened burring holes are applied to low- to mid-rise housings in seismically active and typhoon- or hurricane-prone regions. A configuration with burrs on the inside and smooth on the outside enables the construction of omitting the machining of holes for equipments and thinner walls with simplified attachments of finishings. In-plane shear experiments and finite element analyses revealed that the walls allowed shear stress to concentrate in intervals between the burring holes. The walls maintained stable shear load and large deformation behavior, and the deformation areas were limited in the intervals and a large out-of-plane waveform in a sheet was effectively prevented owing to edge stiffened burring ribs. The design methods are developed for evaluating the shear load of the walls at story angle from zero to 1/100, using the idea of decreasing the band width of the inclined tension fields on the intervals with the effects of the thickness.</p>

Flexibility of Trunnion Piping Elbows

1990 ◽  
Vol 112 (2) ◽  
pp. 184-187 ◽  
Author(s):  
G. D. Lewis ◽  
Y. J. Chao
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Chemical Plants ◽  
The Finite Element Method ◽  
Flexibility Analysis ◽  
Piping Systems ◽  
Out Of Plane ◽  
Element Method

Trunnion piping elbows are commonly used in piping systems in power and chemical plants. The flexibility of the trunnion piping elbows is normally less than that of the plain piping elbows. In this paper, the finite element method is used to derive the in-plane and out-of-plane flexibility factors of trunnion piping elbows. The results can be easily adopted into the piping flexibility analysis.

Development of Flexible Bellows for Large Diameter, Multi Layered and Thin Wall Thickness Stainless for LNG(-161.DEG.C.) Transportation Use.

Materia Japan ◽  
1994 ◽  
Vol 33 (5) ◽  
pp. 650-652
Author(s):  
Yoshiyuki Tashiro ◽  
Shin Kinoshita ◽  
Toshimi Yamane ◽  
Keiichi Hirao ◽  
Shin-ichiroh Yokoyama
Keyword(s):  
Wall Thickness ◽  
Large Diameter ◽  
Thin Wall

Piping Local Stresses for Solid Versus Hollow Attachments

2005 ◽  
Author(s):  
C. Basavaraju ◽  
R. C. Fox
Keyword(s):  
Finite Element ◽  
Wall Thickness ◽  
Cylindrical Shells ◽  
Local Stress ◽  
Support Design ◽  
Element Analysis ◽  
Stress Evaluation ◽  
Local Stresses ◽  
Asme Code ◽  
The Impact

The simple and most commonly used WRC-107 (Welding Research Bulletin #107) Bijlaard methodology for local stress evaluation addresses cylindrical shells and pipes with solid circular, rectangular, and square attachments only. Hollow circular, square, or rectangular tubular shaped attachments on cylindrical shells, though commonly used, are not addressed in WRC-107. ASME Code Case N-392 addresses hollow circular attachments on pipes but is known to be conservative. This paper studies commonly encountered sizes of hollow circular, hollow square, and hollow rectangular attachments of various wall thicknesses on piping utilizing rigorous finite element analysis (FEA) method to obtain the local stresses at the pipe/attachment interface due to mechanical loads. A total of fifty (50) finite element models were analyzed to study the most frequently used configurations. The impact of attachment wall thickness including solid attachment will be addressed. A comparison of finite element results with WRC-107 solid attachment results, when applicable, will be made. Recommendations and guidelines are provided based on the results of the FEA study. The objective is to reduce conservatism, and hence the associated cost in piping and pipe support design by optimizing the round attachment’s wall thickness.

scholarly journals Local stress evaluation of rapid crack propagation in finite element analyses

2018 ◽  
Vol 144-145 ◽  
pp. 66-77 ◽  
Author(s):  
Fuminori Yanagimoto ◽  
Kazuki Shibanuma ◽  
Yo Nishioka ◽  
Yuya Shirai ◽  
Katsuyuki Suzuki ◽  
...  
Keyword(s):  
Finite Element ◽  
Crack Propagation ◽  
Local Stress ◽  
Finite Element Analyses ◽  
Stress Evaluation ◽  
Rapid Crack Propagation

A Study on the Large-Diameter Seamless Gas Cylinder Dimensional Accuracy of Rotary Expanding Process with Finite Element Analysis

2011 ◽  
Vol 328-330 ◽  
pp. 136-142
Author(s):  
Shun Yao Jin ◽  
Zhong Guo Huang ◽  
Zong Ke Shao ◽  
Ming Xiang Li ◽  
Hui Lai Sun ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Wall Thickness ◽  
Large Diameter ◽  
Dimensional Accuracy ◽  
Steel Tube ◽  
Element Analysis ◽  
Thickness Uniformity ◽  
Gas Cylinder ◽  
Roll Gap

This paper expounds the application of rotary expanding process to manufacture the large-diameter hot-rolled seamless gas cylinder. Through analytic geometry method, an equation is established among the tail roll gap, roll distance and the plug protrusion distance. 3D drawing software CATIA-V5 is applied to build 3d models of steel tube and rolling tools. The rolling process is simulated by MSC.Marc FEA (finite element analysis) software. Marc’s second development function and FORTRAN software’s extracting finite element node coordinates function are applied to calculate the wall thickness uniformity. A novel method to calculate the wall thickness uniformity after finite element analysis is proposed. The wall thickness uniformity of steel tube after rolling is well simulated and compared by MSC.Marc FEA software, which can help the technologist to predict and choose the best rolling parameter. For gas cylinder rolling, the tail roll gap should be set to 17mm. The roller distance and the plug protrusion distance should be set as 342mm and 78mm separately.

Attenuation Effects of a Single Deck Floating Roof in a Liquid Storage Tank

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Mohammad Ali Goudarzi
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Numerical Model ◽  
Analytical Solution ◽  
Plane Deformation ◽  
Fem Analysis ◽  
Geometrical Parameters ◽  
Empirical Formulas ◽  
Out Of Plane ◽  
Element Method

Liquid-roof interaction imposes a complicated distribution of out-of-plane deformation on the single-deck type floating roof (SDRF), which is the main source of considerable seismic stresses in floating roof. In this paper, an analytical solution for evaluating the dynamic interaction between the liquid and the floating roof is developed. Main physical and geometrical parameters are involved by the proposed analytical solution (PAS) for evaluating the seismic stresses of a single deck floating roof tanks (SDFR). The results of PAS are compared with the results of existing empirical formulas for various dimensions of SDRF tanks. In order to assess the validity of PAS for various sloshing wave height, a numerical model based on finite element method is established and the PAS results are compared with the finite element method (FEM) analysis results. The PAS predictions are in very good agreement with both the available empirical formula and the numerical model results.

Heterogeneous, Variable Wall-Thickness Modeling of a Ruptured Abdominal Aortic Aneurysm

2004 ◽  
Author(s):  
Madhavan Raghavan ◽  
Jarin Kratzberg ◽  
Erasmo Sima˜o da Silva
Keyword(s):  
Finite Element ◽  
Wall Thickness ◽  
Regional Distribution ◽  
Uniaxial Extension ◽  
Aortic Aneurysms ◽  
Surface Model ◽  
Thin Wall ◽  
Material Parameters ◽  
Abdominal Aortic ◽  
Rupture Site

Pressure-induced mechanical stress in ruptured abdominal aortic aneurysms (AAA) was investigated using a finite element model with measured variations in wall thickness and material properties. We harvested an 8-cm ruptured AAA from a cadaver and recorded its geometry on bi-plane photographs and three-dimensionally reconstructed. The wall thickness was measured at over 100 sites on the aneurysm surface using digital calipers. Regional mechanical property variation (failure strengths and hyperelastic material parameters) was determined using data from uniaxial extension tests of 19 test strips cut from various regions of the AAA surface. The measured data for wall thickness and mechanical properties were transferred to the 3D AAA surface model and nonlinearly interpolated on the surface to obtain the point-to-point regional distribution for thickness and material parameters. Modeling the AAA as a thick shell, finite element stress analysis was performed. The peak stress was found to be exactly at the rupture site and was substantially higher than population averages. The measured low wall thickness at the rupture site appeared to play a major role in elevating stresses indicating that localized thin wall may be an important risk factor for AAA rupture.

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