Strength of a Pipe Mitred Bend

1970 ◽  
Vol 92 (4) ◽  
pp. 767-773 ◽  
Author(s):  
Jaroslaw Sobieszczanski
Keyword(s):  
Internal Pressure ◽  
Maximum Stress ◽  
Cylindrical Shells ◽  
Beam Theory ◽  
The Self ◽  
Design Work ◽  
Stress And Deformation

Single and multiple mitred bends are analyzed for stress and deformation due to inplane bending and internal pressure. Theory of cylindrical shells is used as a tool of analysis. Results show maximum stress at the elbow increased up to more than 400 percent of the stress predicted by elementary beam theory. Influence of the elbow on the self-compensation of the heated pipeline is discussed and the local reinforcements proposed. Solutions are presented as graphs which may be directly applied in design work.

Analytical modeling for offshore composite rubber hose with spiral stiffeners under internal pressure

2020 ◽  
pp. 073168442096257
Author(s):  
Pan Gao ◽  
Qiang Gao ◽  
Chen An ◽  
Ji Zeng
Keyword(s):  
Internal Pressure ◽  
Radial Displacement ◽  
Beam Theory ◽  
Element Model ◽  
Radial Deformation ◽  
Shear Stresses ◽  
Rubber Hose ◽  
Filament Wound ◽  
Practical Engineering ◽  
Stress And Deformation

Internal pressure is the most important functional load for the offshore composite rubber hose. In this paper, the stress and radial displacement of the hose under internal pressure are investigated. The hose dimensions are length of 10.7 m and nominal bore diameter of 500 mm. The composite structure is mainly composed of cord-rubber reinforcement layers and a spiral steel stiffener. To calculate the stress and deformation of the hose, the stiffener and composite cord-rubber layers are theoretically analyzed based on the Euler–Bernoulli beam theory and the Donnell shell theory, respectively. The stiffener distinguishes the hose from common filament wound un-stiffened composite pipes in regard to the stress distribution and radial deformation. It is found that the stiffener plays an important role in affecting the mechanical behavior of composite reinforcement. Influences of the cord-winding angle, the stiffener spacing, and the stiffener’s tensile stiffness on the axial, hoop and shear stresses, and the radial displacement are investigated. The analytical model shows a good agreement with the finite element model. It is supposed to be of significant reference for practical engineering.

Investigation of Strength and Dynamic Characteristics for the Rolling Mill

2013 ◽  
Vol 706-708 ◽  
pp. 1405-1408
Author(s):  
Xi Ping Guo ◽  
Shuang Zhou
Keyword(s):  
Natural Frequency ◽  
Dynamic Characteristics ◽  
Rolling Mill ◽  
Maximum Stress ◽  
Weak Link ◽  
Deformation Analysis ◽  
Vibration Model ◽  
Strength And Stiffness ◽  
Stress And Deformation ◽  
Diagram Analysis

Stress and deformation analysis of 950 mill housing was done by means of ANSYS to calculate the maximum stress and deformation. Strength and stiffness of the mill roll were checked to meet requirements. Carries on the modal analysis to the rolling-mill housing, obtains its first 10 steps the natural frequency and the mode of vibration, through the vibration model diagram analysis frame of the weak link,and it is significant for similar mill housing designs.

The Failure Window Method and Its Application in Pipeline Burst

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Zhanfeng Chen ◽  
Hao Ye ◽  
Sunting Yan ◽  
Xiaoli Shen ◽  
Zhijiang Jin
Keyword(s):  
Internal Pressure ◽  
Maximum Stress ◽  
Oil And Gas ◽  
Maximum Shear Stress ◽  
High Accuracy ◽  
Burst Pressure ◽  
Empirical Equations ◽  
Integrity Assessment ◽  
Wall Thinning ◽  
Window Method

Accurate prediction of the burst pressure is indispensible for the engineering design and integrity assessment of the oil and gas pipelines. A plenty of analytical and empirical equations have been proposed to predict the burst pressures of the pipelines; however, it is difficult to accurately predict the burst pressures and evaluate the accuracy of these equations. In this paper, a failure window method was presented to predict the burst pressure of the pipes. First, the security of the steel pipelines under the internal pressure can be assessed. And then the accuracy of the previous analytical and empirical equations can also be generally evaluated. Finally, the effect of the wall thinning of the pipes on the failure window was systemically investigated. The results indicate that it is extremely formidable to establish an equation to predict the burst pressure with a high accuracy and a broad application, while it is feasible to create a failure window to determine the range of the dangerous internal pressure. Calculations reveal that some predictions of the burst pressure equations like Faupel, Soderberg, Maximum stress, and Nadai (1) are overestimated to some extent; some like ASME, maximum shear stress, Turner, Klever and Zhu–Leis and Baily–Nadai (2) basically reliable; the rest like API and Nadai (3) slightly conservative. With the wall thinning of the steel pipelines, the failure window is gradually lowered and narrowed.

scholarly journals Comparative Analysis of Static Loading Performance of Rigid and Flexible Road Wheel based on Finite Element Method

2020 ◽  
Vol 70 (1) ◽  
pp. 41-46
Author(s):  
Yaoji Deng ◽  
Youqun Zhao ◽  
Mingmin Zhu ◽  
Zhen Xiao ◽  
Qiuwei Wang
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Static Loading ◽  
Maximum Stress ◽  
Three Dimensional ◽  
Element Model ◽  
Vertical Load ◽  
New Type ◽  
Stress And Deformation ◽  
Nonlinear Finite Element Model

To overcome the shortcomings of traditional rigid road wheel, such as poor damping effect and low load-bearing efficiency, a new type of flexible road wheel, having a unique suspension-bearing mode, was introduced. The three-dimensional nonlinear finite element model of rigid and flexible road wheel, considering the triple nonlinear characteristics of geometry, material and contact, is established for numerical investigation of static loading performance. The accuracy of the finite element model of the rigid and flexible road wheel is verified by static loading experiment. The static loading performance of the rigid and flexible road wheels is numerically analyzed. The influence of vertical load on maximum stress and deformation of the rigid and flexible wheels is also studied. The results show that the contact pressure uniformity of the flexible road wheel is better than that of the rigid road wheel under the static vertical load, but the maximum stress and deformation of the flexible road wheel are greater than that of the rigid road wheel. However, this problem can be solved by increasing the number of hinge sets and optimising the joints. The research results provide theoretical basis for replacing rigid road wheel with flexible road wheel, and also provide reference for structural optimisation of flexible road wheel.

scholarly journals Quasistatic Nonlinear Analysis of a Drill Pipe in Subsea Xmas Tree Installation

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Haozhi Qin ◽  
Jian Liu ◽  
Wensheng Xiao ◽  
Bingxiang Wang
Keyword(s):  
Nonlinear Analysis ◽  
Wave Height ◽  
Drill Pipe ◽  
Beam Theory ◽  
Sea State ◽  
Variable Parameters ◽  
Towing Speed ◽  
Stress And Deformation ◽  
Method Accuracy ◽  
Euler Bernoulli Beam

To analyse the stress and deformation of a drill pipe during the lowering of a subsea Xmas tree, a mechanical analytical model and equation were established based on Euler-Bernoulli beam theory. The wave phase is selected as one of the variable parameters for analysis of the deformation and stress of the drill pipe. The research results indicate that the maximum response occurs at 0 radians in the scope of 0 to 2π, and the quasistatic nonlinear analysis is analysed at 0. In addition, Orcaflex software is applied for simulation, and the simulation results are compared with the results from proposed method, which demonstrate the model and the method accuracy. Factors that affect the installation process are discussed, such as current velocity, wave height, pipe size, and towing speed. The results show that all factors have remarkable effects on stress and deformation and that the wave height has a lesser effect on the deformation of the drill pipe. The viable towing speed is chosen by discussing the total stress of the drill pipe with various towing speeds and is notably useful for installation in the real sea state.

On A Formulation of the Elastic Stability Equations of Circular Cylindrical Shells Under Variable Internal Pressure

1985 ◽  
Vol 9 (2) ◽  
pp. 64-69
Author(s):  
J.L. Urrutia-Galicia ◽  
A.N. Sherbourne
Keyword(s):  
Mathematical Model ◽  
Internal Pressure ◽  
Cylindrical Shells ◽  
Direct Analysis ◽  
Elastic Stability ◽  
Equilibrium Path ◽  
Circular Cylindrical Shells ◽  
The Stability ◽  
Variable Internal Pressure ◽  
The Mathematical Model

The mathematical model of the stability analysis of circular cylindrical shells under arbitrary internal pressure is presented. The paper consists of a direct analysis of the equilibrium modes in the neighbourhood of the unperturbed principal equilibrium path. The final stability condition results in a completely symmetric differential operator which is then compared with current theories found in the literature.

Sign in / Sign up

Export Citation Format

Share Document