Residual Stress Simulation in Multi-Pass Weld of Stainless Steel Pipes

A numerical scheme for the determination of thermally induced local residual stresses and their relaxation behavior during heat treatment in the case of butt-welded pipes is described. The procedure is illustrated by considering 304 stainless steel and SAE 1020 steel pipes. The results are compared with available experimental and numerical results.

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Residual Stress Generation and Relaxation in Butt-Welded Pipes

Journal of Pressure Vessel Technology ◽

10.1115/1.3264184 ◽

1982 ◽

Vol 104 (1) ◽

pp. 42-46 ◽

Cited By ~ 4

Author(s):

S. Nair ◽

E. Pang ◽

R. C. Dix

Keyword(s):

Heat Treatment ◽

Residual Stress ◽

Stainless Steel ◽

Residual Stresses ◽

Numerical Scheme ◽

Stress Generation ◽

304 Stainless Steel ◽

Thermally Induced ◽

Steel Pipes

A numerical scheme for the determination of thermally induced local residual stresses and their relaxation behavior during heat treatment in the case of butt-welded pipes is described. The procedure is illustrated by considering 304 stainless steel and SAE 1020 steel pipes. The results are compared with available experimental and numerical results.

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The Effect of Pipe Thickness on Residual Stresses due to Girth Welds

Journal of Pressure Vessel Technology ◽

10.1115/1.3264205 ◽

1982 ◽

Vol 104 (3) ◽

pp. 204-209 ◽

Cited By ~ 46

Author(s):

E. F. Rybicki ◽

P. A. McGuire ◽

E. Merrick ◽

J. Wert

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Residual Stresses ◽

304 Stainless Steel ◽

Stress Distributions ◽

Intergranular Stress Corrosion ◽

Steel Pipes ◽

Inner Surface ◽

Girth Welds ◽

Intergranular Stress Corrosion Cracking

This paper addresses the question of what effect the pipe thickness has on weld residual stresses in 304 stainless steel piping. Two diameters are considered. These are nominal 4-in. and 10-in. diameters. Four pipe wall thicknesses corresponding to schedules 10, 40, 80, and 160 are examined for each pipe. The focus is on residual stress distributions on the pipe inner surface because this is a primary site for intergranular stress corrosion cracking in 304 stainless steel pipes. The trends in residual stress values are toward more compressive stresses at the pipe inner surface for thicker pipes with the same nominal diameter. Residual axial stresses for the thick 10-in. schedule 160 pipe were found to be compressive while those for the thinner schedule 80 pipe were tensile. X-ray residual stress data for a 6-in-dia schedule 160 pipe fall between the results for the 4-in. and 10-in. schedule 160 pipes and support the findings of the study.

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Evaluation of the residual stress in stainless steel 304L hydraulically expanded joints

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1177/0954408920964019 ◽

2020 ◽

pp. 095440892096401

Author(s):

Ying Hong ◽

Xuesheng Wang ◽

Yan Wang ◽

Zhao Zhang ◽

Yong Han

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Yield Strength ◽

Residual Stresses ◽

Heat Exchangers ◽

Nuclear Power ◽

The Finite Element Method ◽

Power Stations ◽

Stainless Steel 304 ◽

Initial Clearance

Stainless steel 304 L tubes are commonly used in the fabrication of heat exchangers for nuclear power stations. The stress corrosion cracking (SCC) of 304 L tubes in hydraulically expanded tube-to-tubesheet joints is the main reason for the failure of heat exchangers. In this study, 304 L hydraulically expanded joint specimens were prepared and the residual stresses of a tube were evaluated with both an experimental method and the finite element method (FEM). The residual stresses in the outer and inner surfaces of the tube were measured by strain gauges. The expanding and unloading processes of the tube-to-tubesheet joints were simulated by the FEM. Furthermore, an SCC test was carried out to verify the results of the experimental measurement and the FEM. There was good agreement between the FEM and the experimental results. The distribution of the residual stress of the tube in the expanded joint was revealed by the FEM. The effects of the expansion pressure, initial tube-to-hole clearance, and yield strength of the tube on the residual stress in the transition zone that lay between the expanded and unexpanded region of the tube were investigated. The results showed that the residual stress of the expanded joint reached the maximum value when the initial clearance was eliminated. The residual stress level decreased with the decrease of the initial tube-to-hole clearance and yield strength. Finally, an effective method that would reduce the residual stress without losing tightness was proposed.

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Neutron diffraction residual stress measurements on girth-welded 304 stainless steel pipes with weld metal deposited up to half and full pipe wall thickness

International Journal of Pressure Vessels and Piping ◽

10.1016/j.ijpvp.2012.08.003 ◽

2013 ◽

Vol 101 ◽

pp. 1-11 ◽

Cited By ~ 15

Author(s):

R.D. Haigh ◽

M.T. Hutchings ◽

J.A. James ◽

S. Ganguly ◽

R. Mizuno ◽

...

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Neutron Diffraction ◽

Weld Metal ◽

Wall Thickness ◽

Pipe Wall ◽

304 Stainless Steel ◽

Pipe Wall Thickness ◽

Steel Pipes ◽

Stress Measurements

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Residual Stresses Induced by Surface Working and Their Improvement by Emery Paper Polishing

Quantum Beam Science ◽

10.3390/qubs4020021 ◽

2020 ◽

Vol 4 (2) ◽

pp. 21

Author(s):

Makoto Hayashi

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Fatigue Strength ◽

Residual Stresses ◽

Diffraction Method ◽

304 Stainless Steel ◽

Heat Treated ◽

Emery Paper ◽

Type 304 ◽

Type 304 Stainless Steel

In many of machine parts and structural components, materials surface would be worked. In this study, residual stresses on the surfaces were measured by X-ray diffraction method, and effects of surface working on the residual stresses were examined. In case of lathe machining of type 304 stainless steel bar, the residual stresses in circumferential directions are tensile, and those in axial directions are almost compressive. Highly tensile residual stresses in the circumferential directions were improved by emery paper polishing. 10 to 20 times of polishing changes high tensile residual stresses to compressive residual stresses. In the case of shot peening on a type 304 stainless steel plate, the compressive residual stress inside is several hundred MPa lower than that on the surface. By applying the emery paper polishing to the shot peened surface 10 or 20 times, the residual stress on the surface is improved to −700 MPa. While fatigue strength at 288 °C in the air of the shot peened material is 30 MPa higher than solution heat treated and electro-polished material, the fatigue strength of the shot peened and followed by emery paper polished material is 60 MPa higher. Thus, the emery paper polishing is simple and a very effective process for improvement of the residual stresses.

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Residual Stresses Prediction for CO2 Laser Butt-Welding of 304-Stainless Steel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.3-4.125 ◽

2006 ◽

Vol 3-4 ◽

pp. 125-130 ◽

Cited By ~ 5

Author(s):

Khaled Y. Benyounis ◽

Abdul Ghani Olabi ◽

M.S.J. Hashmi

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Residual Stresses ◽

Laser Power ◽

Travel Speed ◽

304 Stainless Steel ◽

Hole Drilling ◽

Design Matrix ◽

Butt Welding ◽

Input Variables

Residual stresses are an integral part of the total stress acting on any component in service. It is important to determine and/or predict the magnitude, nature and direction of the residual stress to estimate the life of important engineering parts, particularly welded components. This work aims to introduce experimental models to predict residual stresses in the heat-affected zone (HAZ). These models specify the effect of laser welding input parameters on maximum residual stress and its direction. The process input variables considered in this study are laser power (1.03 - 1.368 kW), travel speed (26.48 – 68.52 cm/min) and focal point position (- 1 to 0 mm). Laser butt-welding of 304 stainless steel plates of 3 mm thick were investigated using a 1.5 kW CW CO2 Rofin laser as a welding source. Hole-drilling method was employed to measure the magnitude, and direction of the maximum principal stress in and around the HAZ, using a CEA-06- 062UM-120 strain gauge rosette, which allows measurement of the residual stresses close to the weld bead. The experiment was designed based on Response Surface Methodology (RSM). Fifteen different welding conditions plus 5 repeat tests were carried out based on the design matrix. Maximum principal residual stresses and their directions were calculated for the twenty samples. The stepwise regression method was selected using Design-expert software to fit the experimental responses to a second order polynomial. Sequential F test and other adequacy measures were then used to check the models adequacy. The experimental results indicate that the proposed mathematical models could adequately describe the residual stress within the limits of the factors being studied. Using the models developed, the main and interaction effect of the process input variables on the two responses were determined quantitatively and presented graphically. It is observed that the travel speed and laser power are the main factors affecting the behavior of the residual stress. It is recommended to use the models to find the optimal combination of welding conditions that lead to minimum distortion.

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Effect of Temperature on Strength and Residual Stress Distribution in Silicon Nitride to 304 Stainless Steel Brazed Joints

Materials Science Forum ◽

10.4028/www.scientific.net/msf.449-452.881 ◽

2004 ◽

Vol 449-452 ◽

pp. 881-884 ◽

Cited By ~ 1

Author(s):

Do Won Seo ◽

Ho Chel Yoon ◽

Jin Yi Lee ◽

Jae Kyoo Lim

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

High Temperature ◽

Silicon Nitride ◽

Residual Stresses ◽

Bending Strength ◽

304 Stainless Steel ◽

Effect Of Temperature ◽

High Temperature Strength ◽

Mechanical And Thermal Properties

Ceramics are significantly used in many industrial applications due to their excellent mechanical and thermal properties such as high temperature strength, low density, high hardness, low thermal expansion and good corrosion properties. To combine the specific advantages of ceramics with that of metals, they are often used together within one composite component. In this study, the effect of temperature on fracture characteristics of silicon nitride joined to 304 stainless steel brazed with Ti active alloy are investigated in room and high temperature regions. And analytical studies on the residual stress of dissimilar brazed joint are performed by the finite element method. Four-point bending strength and deflection of interlayer increase with increasing strain rate in room temperature. As the test temperature increases, the bending strength decreases, but the deflection of interlayer is almost constant. The residual stresses redistribute after cutting of joint and the maximum tensile stress occurs on the new free surface at the ceramic near the interface. The singularity of residual stresses at the ceramic near the interface is characterized by elastic-plastic properties of ceramic and inserted materials.

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Development of Residual Stress Simulation and Experimental Measurement Tools for Stainless Steel Pressure Vessels

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2015-45655 ◽

2015 ◽

Author(s):

Thomas B. Reynolds ◽

Arthur A. Brown ◽

Lauren L. Beghini ◽

Timothy D. Kostka ◽

Chris W. San Marchi

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Residual Stresses ◽

Pressure Vessels ◽

Contour Method ◽

Residual Stress State ◽

Measurement Tools ◽

Fatigue And Fracture ◽

Evolution Of Microstructure ◽

Stress Simulation

In forged, welded, and machined components, residual stresses can form during the fabrication process. These residual stresses can significantly alter the fatigue and fracture properties compared to an equivalent component containing no residual stress. When performing lifetime assessment, the residual stress state must be incorporated into the analysis to most accurately reflect the initial condition of the component. The focus of this work is to present the computational and experimental tools that we are developing to predict and measure the residual stresses in stainless steel for use in pressure vessels. The contour method was used to measure the residual stress in stainless steel forgings. These results are compared to the residual stresses predicted using coupled thermo-mechanical simulations that track the evolution of microstructure, strength and residual stress during processing.

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