scholarly journals Effect of Head Types on the Free Vibration and Fatigue for Horizontal LPG Pressure Vessels

2018 ◽  
Vol 21 (4) ◽  
pp. 494-500
Author(s):  
Marwan Abdulrazzaq Salman ◽  
Mahmud Rasheed Ismail ◽  
Yassr Y. Kahtan
Keyword(s):  
Fatigue Life ◽  
Pressure Vessel ◽  
Natural Frequencies ◽  
Pressure Vessels ◽  
Mode Shapes ◽  
Liquefied Petroleum Gas ◽  
Oil Refineries ◽  
Periodic Loading ◽  
Spherical Head ◽  
Horizontal Pressure

Pressure vessels are the heart of plants and oil refineries stations. In many engineering applications such vessels can be subjected to periodic loading either internally due to the charging and discharging process or externally due to the excitation from other nearby components such as pumps, compressors or from seismic. So that in spite of a good design according static assumption it may be critical in dynamics. In this work a horizontal pressure vessel with accessories subjected to liquefied petroleum gas pressure LPG is considered. Three models of different head types are investigated herein namely; Deep torispherical, Elliptical 2:1 and Hemispherical. The design and material selections are chosen as per ASME. For practical service many accessories are attached to the vessel such as manhole, supports, inlet and outlet opining. Finite Element method via ANSYS R18.2 is introduced for the numerical analysis. The fatigue life in case of fully reversed cyclic loading are estimated and located. Vibration characteristics such as mode shapes and natural frequencies for the lowest five modes are evaluated and compared. It is found that the fatigue life can be increased as higher as 180% for hemi- spherical head as compared with deep torispherical head pressure vessel and the lowest four natural frequencies are nearly identical for all models, however significant change observed in the fifth natural frequency.

scholarly journals A Better Way to Support Horizontal Pressure Vessels Subject to Thermal Loading

1997 ◽  
Author(s):  
Alwyn S. Tooth ◽  
John S. T. Cheung ◽  
Heong W. Ng ◽  
Lin S. Ong ◽  
Chithranjan Nadarajah
Keyword(s):  
High Temperature ◽  
Fatigue Life ◽  
Pressure Vessel ◽  
Thermal Loading ◽  
Thermal Stresses ◽  
Pressure Vessels ◽  
Sliding Surface ◽  
Current Design ◽  
Horizontal Pressure ◽  
Regular Site

When storing liquids at high temperature, in horizontal vessels, the current design methods aim to minimise the thermal stresses by introducing a sliding surface at the base of one of the twin saddle supports. However, regular site maintenance is required to ensure that adequate sliding is achieved This may be difficult and costly to carry out. The aim of the present work, therefore, is to dispense with the sliding support and to provide saddle designs which although fixed to the platform, or foundation, do not result in the storage/pressure vessel being over-stressed when thermal loading occurs. The paper provides general recommendations for the most appropriate saddle geometries, and details the way in which ‘Design by Analysis’ and ‘Fatigue Life Assessments’ may be carried out using the stresses which arise from these designs.

A Study on Fatigue Life Evaluation of Pressure Vessel Made of ASME SA240-316L Material Using Numerical Analysis

2019 ◽  
Vol 893 ◽  
pp. 1-5 ◽  
Author(s):  
Eui Soo Kim
Keyword(s):  
Finite Element ◽  
Fatigue Life ◽  
Pressure Vessel ◽  
Life Prediction ◽  
Pressure Vessels ◽  
Physical Damage ◽  
Element Analysis ◽  
Internal Damage ◽  
Life Evaluation ◽  
Fatigue Life Evaluation

Pressure vessels are subjected to repeated loads during use and charging, which can causefine physical damage even in the elastic region. If the load is repeated under stress conditions belowthe yield strength, internal damage accumulates. Fatigue life evaluation of the structure of thepressure vessel using finite element analysis (FEA) is used to evaluate the life cycle of the structuraldesign based on finite element method (FEM) technology. This technique is more advanced thanfatigue life prediction that uses relational equations. This study describes fatigue analysis to predictthe fatigue life of a pressure vessel using stress data obtained from FEA. The life prediction results areuseful for improving the component design at a very early development stage. The fatigue life of thepressure vessel is calculated for each node on the model, and cumulative damage theory is used tocalculate the fatigue life. Then, the fatigue life is calculated from this information using the FEanalysis software ADINA and the fatigue life calculation program WINLIFE.

A Study of Nozzles in Pressure Vessels under Pressure Fatigue Loading

1967 ◽  
Vol 182 (1) ◽  
pp. 657-684 ◽  
Author(s):  
J. Spence ◽  
W. B. Carlson
Keyword(s):  
Fatigue Life ◽  
Mild Steel ◽  
Pressure Vessel ◽  
Special Interest ◽  
Maximum Stress ◽  
Fatigue Loading ◽  
Fatigue Tests ◽  
Pressure Vessels ◽  
Full Size

Nozzles in cylindrical vessels have been of special interest to designers for some time and have offered a field of activity for many research workers. This paper presents some static and fatigue tests on five designs of full size pressure vessel nozzles manufactured in two materials. Supporting and other published work is reviewed showing that on the basis of the same maximum stress mild steel vessels give the same fatigue life as low alloy vessels. When compared on the basis of current codes it is shown that mild steel vessels may have five to ten times the fatigue life of low alloy vessels unless special precautions are taken.

Kendall Analysis of Cannon Pressure Vessels

2012 ◽  
Author(s):  
John H. Underwood
Keyword(s):  
Fatigue Life ◽  
Yield Strength ◽  
Pressure Vessel ◽  
Structural Integrity ◽  
Pressure Vessels ◽  
Full Scale ◽  
Compressive Yield Strength ◽  
Us Army ◽  
Post Test ◽  
Engineering Mechanics

Engineering mechanics analysis of cannon pressure vessels is described with special emphasis on the work of the late US Army Benet Laboratories engineer David P. Kendall. His work encompassed a broad range of design and analysis of high pressure vessels for use as cannons, including analysis of the limiting yield pressure for vessels, the autofrettage process applied to thick vessels, and the fatigue life of autofrettaged cannon vessels. Mr. Kendall’s work has become the standard approach used to analyze the structural integrity of cannon pressure vessels at the US Army Benet Laboratories. The methods used by Kendall in analysis of pressure vessels were simple and direct. He used classic results from research in engineering mechanics to develop descriptive expressions for limiting pressure, autofrettage residual stresses and fatigue life of cannon pressure vessels. Then he checked the expressions against the results of full-scale cannon pressure vessel tests in the proving grounds and the laboratory. Three types of analysis are described: [i] Yield pressure tests of cannon sections compared with a yield pressure expression, including in the comparison post-test yield strength measurements from appropriate locations of the cannon sections; [ii] Autofrettage hoop residual stress measurements by neutron diffraction in cannon sections compared with expressions, including Bauschinger corrections in the expressions to account for the reduction in compressive yield strength near the bore of an autofrettaged vessel; [iii] Fatigue life tests of cannons following proving ground firing and subsequent laboratory simulated firing compared with Paris-based fatigue life expressions that include post-test metallographic determination of the initial crack size due to firing. Procedures are proposed for Paris life calculations for bore-initiated fatigue affected by crack-face pressure and notch-initiated cracking in which notch tip stresses are significantly above the material yield strength. The expressions developed by Kendall and compared with full-scale cannon pressure vessel tests provide useful first-order design and safety checks for pressure vessels, to be followed by further engineering analysis and service simulation testing as appropriate for the application. Expressions are summarized that are intended for initial design calculations of yield pressure, autofrettage stresses and fatigue life for pressure vessels. Example calculations with these expressions are described for a hypothetical pressure vessel.

Support Analysis of Horizontal Pressure Vessel Using FEA

2014 ◽  
Vol 592-594 ◽  
pp. 1220-1224
Author(s):  
Navin Kumar ◽  
Surjit Angra ◽  
Vinod Kumar Mittal
Keyword(s):  
Stress Analysis ◽  
Pressure Vessel ◽  
Theoretical Basis ◽  
Pressure Vessels ◽  
Loading Conditions ◽  
Ansys Software ◽  
Support Design ◽  
Horizontal Pressure ◽  
The Given

Saddles are used to support the horizontal pressure vessels such as boiler drums or tanks. Since saddle is an integral part of the vessel, it should be designed in such a way that it can withstand the pressure vessel load while carrying liquid along with the operating weight. This paper presents the stress analysis of saddle support of a horizontal pressure vessel. A model of horizontal pressure vessel and saddle is created in Ansys software. For the given boundry and loading conditions, stresses induced in the saddle support are analyzed using Ansys software. After analysis it is found that maximum localized stress arises at the saddle to vessel interface near the saddle horn area. The results obtained shows that the saddle support design is safe for the given loading conditions and provides the theoretical basis for furthur optimisation.

scholarly journals Residual Stresses in Weld-Deposited Clad Pressure Vessels and Nozzles

1999 ◽  
Vol 121 (4) ◽  
pp. 423-429 ◽  
Author(s):  
D. P. Jones ◽  
W. R. Mabe ◽  
J. R. Shadley ◽  
E. F. Rybicki
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Pressure Vessel ◽  
Fatigue Testing ◽  
Pressure Vessels ◽  
Flat Plates ◽  
Spherical Head ◽  
Layer Removal Method ◽  
Ring Segment ◽  
Cladding Material

Results of through-thickness residual stress measurements are provided for a variety of samples of weld-deposited 308/309L stainless steel and Alloy 600 cladding on low-alloy pressure vessel ferritic steels. Clad thicknesses between 5 and 9 mm on samples that vary in thickness from 45 to 200 mm were studied. The samples were taken from flat plates, from a spherical head of a pressure vessel, from a ring-segment of a nozzle bore, and from the transition radius between a nozzle and a pressure vessel shell. A layer removal method was used to measure the residual stresses. The effects of uncertainties in elastic constants (Young’s modulus and Poisson’s ratio) as well as experimental error are assessed. All measurements were done at room temperature. The results of this work indicate that curvature plays a significant role in cladding residual stress and that tensile residual stresses as high as the yield stress can be measured in the cladding material. Since the vessel from which the spherical and nozzle corner samples were taken was hydrotested, and the flat plate specimens were taken from specimens used in mechanical fatigue testing, these results suggest that rather high tensile residual stresses can be retained in the cladding material, even after some mechanical loading associated with hydrotesting.

Fatigue Life of Commercial High Pressure Tubing

2002 ◽  
Author(s):  
Michael D. Mann
Keyword(s):  
High Pressure ◽  
Fatigue Life ◽  
Pressure Vessel ◽  
Pressure Vessels ◽  
Thick Wall ◽  
Pressure Tubing ◽  
Safety And Reliability ◽  
Section Viii ◽  
Critical Components ◽  
Axial Fatigue

Design guidance for high pressure components, has undergone a dramatic change with the release of ASME Section VIII division 3 pressure vessel code. For the first time, a thorough design criteria is available for design of thick wall pressure vessels. The most critical components of a design are safety and reliability. Ultra high-pressure vessels, in most cases, do not have an “infinite” life. The design must therefore be “leak before break” and a design cycle life must be specified. This paper looks at the effects of fatigue on commercial high-pressure tubing under tri-axial fatigue. The tubing investigated is 316 stainless steel 9/16″ and 3/8″ diameter 4100 bar (60,000 psi) tubing. The testing was performed using a tri-axial fatigue machine originally designed by Dr. B. Crossland, Dr. J. L. M. Morrison and Dr. J. S. C. Perry in 1960 and upgraded by the Author. This investigation compares the fatigue life prediction per KD3 in the ASME pressure vessel code Section VIII division 3 and actual test results from the fatigue machine. This verification gives important reliability data for commercial hardware used in high-pressure piping.

Paris Fatigue Life Modeling of Pressure Vessel Service Simulation Tests

2012 ◽  
Vol 134 (5) ◽  
Author(s):  
John H. Underwood ◽  
John J. Keating ◽  
Edward Troiano ◽  
Gregory N. Vigilante
Keyword(s):  
Fatigue Life ◽  
Residual Stresses ◽  
Pressure Vessel ◽  
Base Alloy ◽  
Pressure Vessels ◽  
Full Scale ◽  
Test Results ◽  
X Ray Diffraction ◽  
Life Model ◽  
Nickel Base

Results from four groups of full-scale pressure vessel service simulation tests are described and analyzed using Paris fatigue life modeling. The objective is to determine how the vessel and initial crack configurations and applied and residual stresses control the as-tested fatigue life of the vessel. The tube inner radii are in the 40–80 mm range; wall thickness varies from 6 to 80 mm; materials are ASTM A723 pressure vessel steel and IN718 nickel-base alloy; applied internal pressure varies from 90 to 700 MPa. The Paris constant, C, and exponent, m, that describe the fatigue crack propagation rate versus stress intensity factor range for the various vessel materials, were measured as part of the investigation. Extensive, previously published fatigue life results from baseline A723 pressure vessels with well characterized autofrettage residual stresses and C and m values are used to demonstrate that a Paris fatigue life model gives a good description of the measured life. The same model is then used to determine the variables with predominant control over life in three types of pressure vessel for which less information and tests results are available. A design life for pressure vessels is calculated for a specified very low probability of fatigue failure using the log(N)-normal distribution statistics often used for fatigue of structures. The results of the work showed: (i) X-ray diffraction measurements of through-wall autofrettage residual stresses are in excellent agreement with prior neutron diffraction measurements from a baseline autofrettaged A723 pressure vessel; these verified autofrettage residual stresses then provide critical input to the baseline Paris life modeling; (ii) comparison of the various full-scale fatigue test results with results from the Paris fatigue life model shows close agreement when autofrettage residual stresses are incorporated into models; (iii) model results for A723 steel vessels with yield strength reduced from the initial 1400 MPa value and degree of autofrettage increased from the initial 40% value indicates a significantly improved resistance to brittle failure with no loss of fatigue life; (iv] comparison of model fatigue life results for IN718 nickel-base alloy vessels with their full-scale test results is improved when near-bore residual stresses measured by X-ray diffraction are included in the model calculations.

Life Prediction of Composite Pressure Vessels Using Multi-Scale Approach

2010 ◽  
Author(s):  
Sung Kyu Ha ◽  
Stephen W. Tsai ◽  
Seong Jong Kim ◽  
Khazar Hayat ◽  
Kyo Kook Jin
Keyword(s):  
Fatigue Life ◽  
Stress Analysis ◽  
Pressure Vessel ◽  
Composite Structures ◽  
Life Prediction ◽  
Pressure Vessels ◽  
Multi Scale ◽  
Helical Angle ◽  
Composite Pressure Vessel ◽  
Composite Pressure Vessels

A multi-scale fatigue life prediction methodology of composite pressure vessels subjected to multi-axial loading has been proposed in this paper. The multi-scale approach starts from the constituents, fiber, matrix and interface, leading to predict behavior of ply, laminates and eventually the composite structures. The life prediction methodology is composed of two steps: macro stress analysis and micro mechanics of failure based on fatigue analysis. In the macro stress analysis, multiaxial fatigue loading acting at laminate is determined from finite element analysis (FEM) of composite pressure vessel, and ply stresses are computed using a classical laminate theory (CLT). The micro-scale stresses are calculated in each constituent (i.e. matrix, interface, and fiber) from ply stresses using a micromechanical model. Micromechanics of failure (MMF) was originally developed to predict the strength of composites and now extended to prediction of fatigue life. Two methods are employed in predicting fatigue life of each constituent, i.e. an equivalent stress method for multi-axially loaded matrix, and a critical plane method for the interface. A modified Goodman diagram is used to take into account the generic mean stresses. Damages from each loading cycle are accumulated using Miner’s rule. Each fiber is assumed to follow a probabilistic failure depending on the length. Using the overall micro and macro models established in this study, Monte Carlo simulation has been performed to predict the overall fatigue life of a composite pressure vessel considering statistical distribution of material properties of each constituent and manufacturing winding helical angle.

Prediction of the Low Cycle Fatigue Life of Pressure Vessels

1967 ◽  
Vol 89 (4) ◽  
pp. 858-868 ◽  
Author(s):  
A. G. Pickett ◽  
S. C. Grigory
Keyword(s):  
Fatigue Life ◽  
Stress Analysis ◽  
Pressure Vessel ◽  
Low Cycle Fatigue ◽  
Design Procedure ◽  
Pressure Vessels ◽  
Analysis Method ◽  
Notch Stress ◽  
Fatigue Life Analysis ◽  
Fatigue Evaluation

The bases for ASME Boiler and Pressure Vessel Code, Section III, fatigue evaluation procedures, the fracture mechanics approach to fatigue life analysis, and the notch stress analysis method are reviewed. Fatigue life predictions are compared with the results of materials, model, and full size pressure vessel tests performed for PVRC and AEC. These tests were made in response to the research objectives established by ASME Special Committee to Review Code Stress Basis in 1958. A proposed design procedure based on the notch stress analysis method and experimental results is presented.

Sign in / Sign up

Export Citation Format

Share Document