Acoustically Induced Structural Fatigue of Piping Systems

1999 ◽  
Vol 121 (4) ◽  
pp. 438-443 ◽  
Author(s):  
F. L. Eisinger ◽  
J. T. Francis
Keyword(s):  
Fluid Pressure ◽  
Acoustic Vibration ◽  
Piping System ◽  
Metal Fatigue ◽  
Hydrocarbon Gases ◽  
Structural Fatigue ◽  
Piping Systems ◽  
Geometry Parameter ◽  
Acoustic Fatigue ◽  
The Relationship

Piping systems handling high-pressure and high-velocity steam and various process and hydrocarbon gases through a pressure-reducing device can produce severe acoustic vibration and metal fatigue in the system. It has been previously shown that the acoustic fatigue of the piping system is governed by the relationship between fluid pressure drop and downstream Mach number, and the dimensionless pipe diameter/wall thickness geometry parameter. In this paper, the devised relationship is extended to cover acoustic fatigue considerations of medium and smaller-diameter piping systems.

Designing Piping Systems Against Acoustically Induced Structural Fatigue

1997 ◽  
Vol 119 (3) ◽  
pp. 379-383 ◽  
Author(s):  
F. L. Eisinger
Keyword(s):  
Power Level ◽  
Fluid Pressure ◽  
Acoustic Vibration ◽  
Acoustic Power ◽  
Metal Fatigue ◽  
Operating Life ◽  
Hydrocarbon Gases ◽  
Structural Fatigue ◽  
Inside Diameter ◽  
Piping Systems

Piping systems adapted for handling fluids such as steam and various process and hydrocarbon gases through a pressure-reducing device at high pressure and velocity conditions can produce severe acoustic vibration and metal fatigue in the system. It has been determined that such vibrations and fatigue are minimized by relating the acoustic power level (PWL) to being a function of the ratio of downstream pipe inside diameter D2 to its thickness t2. Additionally, such vibration and fatigue can be further minimized by relating the fluid pressure drop and downstream Mach number to a function of the ratio of downstream piping inside diameter to the pipe wall thickness, as expressed by M2 Δp = f(D2/t2). Pressure-reducing piping systems designed according to these criteria exhibit minimal vibrations and metal fatigue failures and have long operating life.

Acoustic Power and Acoustic Pressure in Piping Systems Handling High Velocity Steam and Gases Through a Pressure Reducing Device

2010 ◽  
Author(s):  
Frantisek L. Eisinger ◽  
Robert Sullivan
Keyword(s):  
High Pressure ◽  
Mach Number ◽  
High Velocity ◽  
Acoustic Pressure ◽  
High Capacity ◽  
Acoustic Power ◽  
Piping System ◽  
Hydrocarbon Gases ◽  
Piping Systems ◽  
Asme Paper

Piping systems handling high-pressure and high-velocity steam and various process and hydrocarbon gases through a pressure reducing device can produce severe vibration of the piping system and noise and pulsation in the surroundings. Utilizing the data published by Carucci, V.A., and Mueller, R.T., 1982, “Acoustically Induced Piping Vibration in High Capacity Pressure Reducing Systems”, ASME Paper No. 82-WA/PVP-8, we develop a relationship for acoustic power and acoustic pressure as a function of the product of the Mach number M and pressure drop Δp (MΔp) through the system. Thirty six cases were evaluated to formulate this relationship.

Modal Analysis of Vibrations in Liquid-Filled Piping Systems

1990 ◽  
Vol 112 (3) ◽  
pp. 311-318 ◽  
Author(s):  
M. W. Lesmez ◽  
D. C. Wiggert ◽  
F. J. Hatfield
Keyword(s):  
Modal Analysis ◽  
Transfer Matrix ◽  
Wave Equations ◽  
Axial Stress ◽  
Fluid Pressure ◽  
Mode Shapes ◽  
Piping System ◽  
Long Wavelength ◽  
Piping Systems ◽  
Single Pipe

The motions of liquid-filled pipe reaches in which long wavelength assumptions are valid can be described by Poisson-coupled axial stress waves in the pipe and in the liquid column, and in the piping structure, by torsional and flexural waves. Based on linearized assumptions, a simultaneous solution of the wave equations is presented. Eigenvalues and mode shapes are derived for the variables fluid pressure and displacements, and pipe forces and displacements. The results are assembled into a transfer matrix, which represents the motion of a single pipe section. Combined with point matrices that describe specified boundary conditions, an overall transfer matrix for a piping system can be assembled. Corresponding state vectors can then be evaluated to predict the piping and liquid motion, and the accompanying forces. The results from two experimental piping systems are compared with the ones obtained by the modal analysis method.

Performance Analysis of Thin Shell Bends under High Pressure and Temperature

2015 ◽  
Vol 787 ◽  
pp. 296-300
Author(s):  
P. Govindaraj ◽  
Mouleeswaran Senthilkumar
Keyword(s):  
High Stress ◽  
Fluid Pressure ◽  
Bending Moment ◽  
Piping System ◽  
High Stress Concentration ◽  
Geometrical Imperfection ◽  
Internal Fluid ◽  
Piping Systems ◽  
The Cost ◽  
Work Effect

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.

scholarly journals Analysis of Symmetrical and Nonsymmetrical Vertical Expansion Loop to Increase Flexibility And Reduce Pipe Stress Based On ASME B31.3

Teknik ◽  
2021 ◽  
Vol 42 (1) ◽  
pp. 63-70
Author(s):  
Pekik Mahardhika ◽  
Adi Wirawan Husodo ◽  
George Endri Kusuma ◽  
Raden Dimas Endro Witjonarko ◽  
Ekky Nur Budiyanto
Keyword(s):  
Fluid Pressure ◽  
Fluid Flows ◽  
Piping System ◽  
Design Code ◽  
Loop Design ◽  
A Value ◽  
Pipe Expansion ◽  
Study Results ◽  
Piping Systems ◽  
Loop 2

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.

Experimental and Numerical Study on Pressure Pulsations Under Various Acoustic Boundary Conditions in Piping Systems

2017 ◽  
Vol 139 (2) ◽  
Author(s):  
Akira Maekawa ◽  
Takashi Tsuji ◽  
Michiyasu Noda ◽  
Tsuneo Takahashi ◽  
Minoru Kato ◽  
...  
Keyword(s):  
Power Plants ◽  
Numerical Study ◽  
Fluid Pressure ◽  
Control Valve ◽  
Acoustic Resonance ◽  
Piping System ◽  
Pressure Pulsations ◽  
Improve Design ◽  
Piping Systems ◽  
Experiment And Simulation

To improve design and troubleshooting techniques of piping systems for operating power plants, it is necessary to investigate, by experiment and simulation, the behavior of fluid inside the piping system in detail. This study was conducted using full-scale piping system under conditions that could seriously threaten the plant operation, by matching pressure pulsations, acoustic resonance, and piping natural frequency. Although piping vibration is reported to influence fluid pressure pulsations, there were no such examples of influence in this experiment. Knowing that the opening ratio of the pressure control valve affects the boundary condition for acoustic resonance, experiment and simulation at different opening ratios were conducted. It has been suggested that the cases in which a valve partially open at 25% or less should not be taken as a closed end. This finding conflicts with such a widespread design assumption.

Study on the Mechanism of Fatigue Failure at Branch Connections Caused by Shell Mode Vibration

2017 ◽  
Author(s):  
Shunji Kataoka
Keyword(s):  
Fatigue Failure ◽  
Design Method ◽  
Acoustic Vibration ◽  
Beam Model ◽  
Stress Concentrations ◽  
Piping Systems ◽  
Mode Vibration ◽  
Rigid Model ◽  
Shell Vibration ◽  
Acoustic Fatigue

Acoustically induced vibration (AIV) is a vibration of piping systems caused by the acoustic loading generated mainly from pressure reducing devices. Recently, the capacities of the pressure reducing systems have been increased and some of the piping systems which are susceptible to acoustic fatigue, such as in flare and depressuring system. Demands on the development of reasonable design method for AIV is increasing. In this paper, the mechanisms of the fatigue failure of branch connection due to AIV were intensively studied. Firstly, the mechanism of the stress concentration was discussed. branch vibration caused by the shell mode vibration was assessed using several branch connection models, massless rigid model, fixed rigid model, and beam model. Next, the relationship between shell-vibration and stress concentrations is studied and re-organized based on acoustic vibration theories. Finally, the risk of the fatigue failure of the branch connection due to acoustic loading was discussed.

Non-Linear Design Verification of Nuclear Power Piping According to ASME III NB/NC

2008 ◽  
Author(s):  
Lingfu Zeng ◽  
Lennart G. Jansson
Keyword(s):  
Nuclear Power ◽  
Design Evaluation ◽  
Piping System ◽  
Design Verification ◽  
Intensive Study ◽  
Non Linear ◽  
Piping Systems ◽  
Design Requirements

A nuclear piping system which is found to be disqualified, i.e. overstressed, in design evaluation in accordance with ASME III, can still be qualified if further non-linear design requirements can be satisfied in refined non-linear analyses in which material plasticity and other non-linear conditions are taken into account. This paper attempts first to categorize the design verification according to ASME III into the linear design and non-linear design verifications. Thereafter, the corresponding design requirements, in particular, those non-linear design requirements, are reviewed and examined in detail. The emphasis is placed on our view on several formulations and design requirements in ASME III when applied to nuclear power piping systems that are currently under intensive study in Sweden.

Comparison of Failure Modes of Piping Systems With Wall Thinning Subjected to In-Plane, Out-of-Plane, and Mixed Mode Bending Under Seismic Load: An Experimental Approach

2010 ◽  
Vol 132 (3) ◽  
Author(s):  
Izumi Nakamura ◽  
Akihito Otani ◽  
Masaki Shiratori
Keyword(s):  
Dynamic Behavior ◽  
Failure Modes ◽  
Seismic Load ◽  
Piping System ◽  
Shake Table ◽  
Shake Table Tests ◽  
Wall Thinning ◽  
Piping Systems ◽  
Out Of Plane ◽  
Plane Bending

Pressurized piping systems used for an extended period may develop degradations such as wall thinning or cracks due to aging. It is important to estimate the effects of degradation on the dynamic behavior and to ascertain the failure modes and remaining strength of the piping systems with degradation through experiments and analyses to ensure the seismic safety of degraded piping systems under destructive seismic events. In order to investigate the influence of degradation on the dynamic behavior and failure modes of piping systems with local wall thinning, shake table tests using 3D piping system models were conducted. About 50% full circumferential wall thinning at elbows was considered in the test. Three types of models were used in the shake table tests. The difference of the models was the applied bending direction to the thinned-wall elbow. The bending direction considered in the tests was either of the in-plane bending, out-of-plane bending, or mixed bending of the in-plane and out-of-plane. These models were excited under the same input acceleration until failure occurred. Through these tests, the vibration characteristic and failure modes of the piping models with wall thinning under seismic load were obtained. The test results showed that the out-of-plane bending is not significant for a sound elbow, but should be considered for a thinned-wall elbow, because the life of the piping models with wall thinning subjected to out-of-plane bending may reduce significantly.

The Influence of Support Hardware and Piping System Seismic Response on Snubber Support Damping

1997 ◽  
Vol 119 (4) ◽  
pp. 451-456 ◽  
Author(s):  
C. Lay ◽  
O. A. Abu-Yasein ◽  
M. A. Pickett ◽  
J. Madia ◽  
S. K. Sinha
Keyword(s):  
Seismic Response ◽  
Fundamental Frequency ◽  
Damping Ratio ◽  
Damping Coefficient ◽  
Piping System ◽  
Nodal Displacement ◽  
Damping Coefficients ◽  
Fundamental Frequencies ◽  
Piping Systems

The damping coefficients and ratios of piping system snubber supports were found to vary logarithmically with pipe support nodal displacement. For piping systems with fundamental frequencies in the range of 0.6 to 6.6 Hz, the support damping ratio for snubber supports was found to increase with increasing fundamental frequency. For 3-kip snubbers, damping coefficient and damping ratio decreased logarithmically with nodal displacement, indicating that the 3-kip snubbers studied behaved essentially as coulomb dampers; while for the 10-kip snubbers studied, damping coefficient and damping ratio increased logarithmically with nodal displacement.

Sign in / Sign up

Export Citation Format

Share Document