A New Approach to Reducing the Stress Concentration Factors of Cross-Bores in Blocks Under High Pressure

Fatigue Life Test

The fundamental design of high pressure joints such as crosses and tees has remained the same for many years. However, the introduction of commercially available high pressure equipment operating at 600 MPa and higher has demanded improved designs for these classic connections. This study presents a new design concept for reducing the stress concentration at intersecting crossbores. Both the finite element analysis and the fatigue test results from the standard high pressure design and the new design are compared. The new approach realizes a 17–25% reduction in the stress concentration factors and a 40% improvement in fatigue life test results when compared to the standard design.

An Estimation Formula of the Stress Concentration Factor of the Butt-Welded Joint

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.353-358.1995 ◽

2007 ◽

Vol 353-358 ◽

pp. 1995-1998

Author(s):

Byeong Choon Goo

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Concentration ◽

Gas Metal Arc Welding ◽

Element Analysis ◽

Butt Weld ◽

Estimation Formula ◽

Metal Arc Welding ◽

Concentration Factors ◽

The purpose of this paper is to develop an estimation formula of stress concentration factors of butt-welded components under tensile loading. To investigate the influence of weld bead profiles on stress concentration factors of double V groove butt-welded joints, butt-welded specimens were made by CO2 gas metal arc welding. And the three main parameters, the toe radius, flank angle and bead height were measured by a profile measuring equipment. By using the measured data, the influence of three parameters on the stress concentration factors was investigated by a finite element analysis. It is shown that the three parameters have similar effects on the stress concentration factors. According to the simulation results, a formula to estimate the stress concentration factors of butt-weld welded structures was proposed and the estimated concentration factors from the formula were compared with the results obtained by the finite element analysis. The two results are in a good agreement.

Experimental, numerical and parametric studies on stress concentration factors of T-joints under tension

Advances in Structural Engineering ◽

10.1177/13694332211049994 ◽

2021 ◽

pp. 136943322110499

Author(s):

Feleb Matti ◽

Fidelis Mashiri

Keyword(s):

Finite Element ◽

Stress Concentration ◽

Numerical Study ◽

Hot Spot ◽

Joint Models ◽

Element Analysis ◽

T Joints ◽

Concentration Factors ◽

Good Agreement

This paper investigates the behaviour of square hollow section (SHS) T-joints under static axial tension for the determination of stress concentration factors (SCFs) at the hot spot locations. Five empty and corresponding concrete-filled SHS-SHS T-joint connections were tested experimentally and numerically. The experimental investigation was carried out by attaching strain gauges onto the SHS-SHS T-joint specimens. The numerical study was then conducted by developing three-dimensional finite element (FE) T-joint models using ABAQUS finite element analysis software for capturing the distribution of the SCFs at the hot spot locations. The results showed that there is a good agreement between the experimental and numerical SCFs. A series of formulae for the prediction of SCF in concrete-filled SHS T-joints under tension were proposed, and good agreement was achieved between the maximum SCFs in SHS T-joints calculated from FE T-joint models and those from the predicted formulae.

23rd International Conference on Offshore Mechanics and Arctic Engineering, Volume 1, Parts A and B ◽

An Assessment of Structural Details in Lightweight Marine Structures

10.1115/omae2004-51260 ◽

2004 ◽

Author(s):

Carlos A. Pereira ◽

Paulo P. Silva ◽

Anto´nio F. Mateus ◽

Joel A. Witz

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Concentration ◽

Failure Modes ◽

Marine Structures ◽

Element Analysis ◽

Linear Finite Element ◽

Structural Details ◽

Concentration Factors ◽

This paper presents the results of investigations into the mechanics and failure modes of structural details usually encountered in lightweight marine structures. The structural analyses are performed using non-linear finite element analysis. The stress concentration factors and expected fatigue lives of the as designed and the as built structural details are evaluated and alternative configurations are discussed with the aim of improving the designs for production.

DETERMINATION OF STRESS CONCENTRATION FACTORS OF A STEAM TURBINE ROTOR USING FINITE ELEMENT ANALYSIS

Journal of Mechanical Engineering ◽

10.3329/jme.v40i2.5355 ◽

1970 ◽

Vol 40 (2) ◽

pp. 137-141

Author(s):

R. Nagendra Babu ◽

K. V. Ramana ◽

K. Mallikarjuna Rao

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Concentration ◽

Steam Turbine ◽

Turbine Rotor ◽

Element Analysis ◽

Steam Turbine Rotor ◽

Fine Mesh ◽

Concentration Factors ◽

Stress Concentration Factors are significant in machine design as it gives rise to localized stress when any change in the design of surface or abrupt change in the cross section occurs. Almost all machine components and structural members contain some form of geometrical or microstructural discontinuities. These discontinuities are very dangerous and lead to failure. So, it is very much essential to analyze the stress concentration factors for critical applications like Turbine Rotors. In this paper Finite Element Analysis (FEA) with extremely fine mesh in the vicinity of the blades of Steam Turbine Rotor is applied to determine stress concentration factors.Keywords: Stress Concentration Factors; FiniteElement Analysis; ANSYS.DOI: 10.3329/jme.v40i2.5355Journal of Mechanical Engineering, Vol. ME 40, No. 2, December 2009 137-141

Finite Element Analysis and Fatigue Evaluation of the Threaded Marine Riser Connector

Journal of Energy Resources Technology ◽

10.1115/1.3231370 ◽

1988 ◽

Vol 110 (2) ◽

pp. 85-92 ◽

Cited By ~ 2

Author(s):

T. Sato ◽

S. Sano ◽

K. Ishikawa ◽

T. Nakano

Keyword(s):

Finite Element ◽

Stress Concentration ◽

External Pressure ◽

Axisymmetric Body ◽

Large Contribution ◽

Marine Riser ◽

Element Analysis ◽

Concentration Factors ◽

Fatigue Evaluation

Finite element analyses were conducted of the threaded marine riser connector which has the main, internal, and external shoulder seals. The objectives of the analyses are to evaluate the fatigue resistance, strength, and seal capability of the connector under the bending, tensile, internal and external pressure loads. An element which models the bending effect in an axisymmetric body is developed and implemented into the computer program ADINA. Using the program, stress concentration factors at the corner and threaded parts of the connector under these loads are obtained. The large contribution of both shoulders to the reduction of the stress concentration factors is found to be quite clear. The seal mechanism and the stress response of the connectors are also clarified. The fatigue evaluation based on ASME Boiler and Pressure Vessel Code, Sec. III, Rules for Construction of Nuclear Power Plant Components, Division 1, Subsection NB are compared with the experimental results.

Stress-Concentration Factors in Circular Hollow Section and Square Hollow Section T-Connections: Experiments, Finite-Element Analysis, and Formulas

Journal of Structural Engineering ◽

10.1061/(asce)st.1943-541x.0000759 ◽

2013 ◽

Vol 139 (11) ◽

pp. 1866-1881 ◽

Cited By ~ 14

Author(s):

L. W. Tong ◽

H. Z. Zheng ◽

F. R. Mashiri ◽

X. L. Zhao

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Concentration ◽

Element Analysis ◽

Hollow Section ◽

Concentration Factors ◽

Circular Hollow Section

STRESS CONCENTRATION FACTORS FOR WELDED TUBULAR T-JOINTS USING FINITE ELEMENT ANALYSIS WITH AUTOMATIC MESH GENERATION

Welding of Tubular Structures ◽

10.1016/b978-0-08-031156-2.50032-4 ◽

1984 ◽

pp. 401-410

Author(s):

M. Arockiasamy ◽

O. Vosikovsky ◽

G.S. Bhuyan ◽

K. Munaswamy

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Concentration ◽

Mesh Generation ◽

Element Analysis ◽

T Joints ◽

Automatic Mesh Generation ◽

Concentration Factors ◽

Automatic Mesh

A New Approach for Prediction of Crankshaft Stiffness and Stress Concentration Factors

10.4271/2010-01-0949 ◽

2010 ◽

Cited By ~ 2

Author(s):

Mehmet Cagri Cevik ◽

Martin Rebbert ◽

Franz Maassen

Keyword(s):

Stress Concentration ◽

New Approach ◽

Concentration Factors ◽

Bolt Thread and Head Fillet Stress Concentration Factors

Journal of Pressure Vessel Technology ◽

10.1115/1.556168 ◽

2000 ◽

Vol 122 (2) ◽

pp. 180-185 ◽

Cited By ~ 23

Author(s):

Terry F. Lehnhoff ◽

Bradley A. Bunyard

Keyword(s):

Stress Concentration ◽

Steel Plates ◽

Element Analysis ◽

Bolted Connection ◽

Thread Profile ◽

Bolt Stress ◽

Concentration Factors ◽

Connection Design ◽

Proof Strength

Linear finite element analysis (FEA) was performed to determine stress concentration factors for the threads and the bolt head fillet in a bolted connection. The FEA models consisted of axisymmetric representations of a bolt and two circular steel plates each 20 mm in thickness. The bolts studied were 8, 12, 16, 20, and 24-mm-dia grade 10.9 metric bolts with the standard M thread profile. The threads were modeled at both the minimum and maximum allowable depths. The fillet between the bolt shank and bolt head connection was modeled at its minimum radius. Each bolt was loaded to its proof strength. A comparison is made to stress concentration factors typically used in bolted connection design. Stress concentration factors in the head fillet were 3.18, 3.23, 3.63, 3.58, and 3.90 for the 8, 12, 16, 20, and 24-mm bolts, respectively. Thread stress concentration factors were highest in the first engaged thread and decreased in each successive thread moving toward the end of the bolt. Stress concentration factors for the shallow thread models ranged from 1.17 to 4.33, 0.87 to 4.32, 0.83 to 4.67, 0.87 to 4.77, and 0.82 to 4.82 for the 8, 12, 16, 20, and 24-mm bolts, respectively. Likewise, stress concentration factors for the deep thread models ranged from 1.18 to 4.80, 0.88 to 4.80, 0.78 to 5.12, 0.83 to 5.17, and 0.82 to 5.22 for the 8, 12, 16, 20, and 24-mm bolts, respectively. [S0094-9930(00)01402-5]

Comparison of Specimen Geometries for Measuring Through-Thickness Tensile Mechanical Properties of Fibre-Reinforced Polymer Composites

Journal of Composites Science ◽

10.3390/jcs5030084 ◽

2021 ◽

Vol 5 (3) ◽

pp. 84

Author(s):

Rory Pemberton ◽

Louise Crocker ◽

Matthew Poole ◽

Richard Shaw ◽

Michael Gower

Keyword(s):

Mechanical Properties ◽

Stress Concentration ◽

Tensile Properties ◽

Experimental Testing ◽

Tensile Failure ◽

Element Analysis ◽

Reinforced Polymer ◽

Fibre Reinforced Polymer ◽

Concentration Factors ◽

Engineering design of fibre-reinforced polymer (FRP) composite components requires reliable methods for measuring out-of-plane mechanical properties in the through-thickness (T-T) material direction. Within this work, existing indirect and direct test methods and geometries for measuring T-T tensile properties have been evaluated through experimental testing and finite element analysis (FEA). Experimental testing showed variations, particularly in failure properties, for both indirect (failure strengths from 10–94 MPa) and direct (failure strengths from 48–62 MPa) geometries. Results were shown to be in good agreement with FEA, which also confirmed stress concentration factors. A linear relationship between the magnitude of stress concentration factors and experimentally determined T-T tensile failure strengths was observed for all but one of the direct geometries evaluated. Improved knowledge of stress concentration factors from this work should help instil confidence for industry to use T-T tensile properties determined from these methods.