A 3D FEM Methodology for the Full-Scale Air Hammer Bit, Teeth and Rock Contact Analysis

2010 ◽  
Vol 156-157 ◽  
pp. 1425-1429 ◽  
Author(s):  
Hai Yan Zhu ◽  
Qing You Liu ◽  
Xiao Hua Xiao ◽  
Jia Jia Jing
Keyword(s):  
Finite Element ◽  
Shear Failure ◽  
Contact Analysis ◽  
Full Scale ◽  
Tensile Failure ◽  
Drilling Process ◽  
Rock Breakage ◽  
3D Fem ◽  
Element Analysis ◽  
Air Hammer

In order to reveal the physical mechanism of air hammer drilling process, using the finite element methods (FEM), a three-dimensional (3D) contact model of full-scale bit, full-scale teeth and rock is established by using free meshing method. We use a Mohr-Coulomb type material model to describe when and how rock fails, and a triangular wave to replace the stress wave. Using the finite element analysis software (ANSYS), the 3D contact analysis of the bit, teeth and rock is carried out. The results show that: aggressive tensile failure may be primarily responsible for rock breakage in air hammer drilling, while compressive failure (or shear failure) may only contribute as a minor player; the distribution of the fragmentation dents can be used to verify the rationality of tooth arrangement; the larger tooth-hole stress of the outside rows mainly responses for the bit failure, while the larger tooth stress of the inside rows contributes as a secondary factor. The results are further calibrated with a series of field applications and research results.

Analyses of Full-Scale Tank Car Shell Impact Tests

2007 ◽  
Author(s):  
Y. H. Tang ◽  
H. Yu ◽  
J. E. Gordon ◽  
M. Priante ◽  
D. Y. Jeong ◽  
...  
Keyword(s):  
Finite Element ◽  
Test Data ◽  
Three Dimensional ◽  
Full Scale ◽  
Collision Dynamics ◽  
Dynamics Modeling ◽  
Dynamics Model ◽  
Rigid Plastic ◽  
Element Analysis ◽  
Closed Form Solutions

This paper describes analyses of a railroad tank car impacted at its side by a ram car with a rigid punch. This generalized collision, referred to as a shell impact, is examined using nonlinear (i.e., elastic-plastic) finite element analysis (FEA) and three-dimensional (3-D) collision dynamics modeling. Moreover, the analysis results are compared to full-scale test data to validate the models. Commercial software packages are used to carry out the nonlinear FEA (ABAQUS and LS-DYNA) and the 3-D collision dynamics analysis (ADAMS). Model results from the two finite element codes are compared to verify the analysis methodology. Results from static, nonlinear FEA are compared to closed-form solutions based on rigid-plastic collapse for additional verification of the analysis. Results from dynamic, nonlinear FEA are compared to data obtained from full-scale tests to validate the analysis. The collision dynamics model is calibrated using test data. While the nonlinear FEA requires high computational times, the collision dynamics model calculates gross behavior of the colliding cars in times that are several orders of magnitude less than the FEA models.

Finite Element Analysis on Axial-Torsional Coupled Vibration of Drill String

2011 ◽  
Vol 291-294 ◽  
pp. 1952-1956 ◽  
Author(s):  
Xue Liang Bi ◽  
Jian Wang ◽  
Zhan Lin Wang ◽  
Shi Hui Sun
Keyword(s):  
Finite Element ◽  
Coupled Model ◽  
Resonance State ◽  
Drill String ◽  
Hole Drilling ◽  
Drilling Process ◽  
Coupled Vibration ◽  
Element Analysis ◽  
Drilling String ◽  
Rotary Speed

In the drilling process, axial vibration, transverse vibration and torsional vibration happen to drilling string. And the coupled vibration is more complex. In the resonance state, drilling string collides with the wall, which causes serious damage on drilling string in a short time and results in economic loss to the drilling operation. In this paper, the regularity of coupled vibration is analyzed by using finite element method. The model of full-hole drilling strings is established. The distribution regularities of coupled resonant frequency are obtained through computer analysis. The coupled model is more accurate than single vibration model. And the gaps of high rotary speed resonance regions are larger. Resonance state can be avoided by changing rotary speed, and drilling accidents can be reduced.

Validation of Sleeve Weld Integrity and Workmanship Level Development

2006 ◽  
Author(s):  
Robert Lazor ◽  
Brock Bolton ◽  
Aaron Dinovitzer
Keyword(s):  
Finite Element ◽  
Numerical Models ◽  
Full Scale ◽  
Loading Conditions ◽  
Element Analysis ◽  
Service Failures ◽  
Applied Loading ◽  
Fea Modeling ◽  
Field And Laboratory Conditions ◽  
Scale Data

Full encirclement repair sleeves with fillet-welded ends are often used as permanent repairs on pipelines to reinforce areas with defects, such as cracks or corrosion. In-service failures have occurred at reinforcing sleeves as a result of defects associated with the sleeve welds, such as hydrogen-induced cracks and undercut at the fillet welds, inadequate weld size, and sleeve longitudinal seam ruptures. This work was undertaken to support the development of tools for sleeve design and for conducting an engineering assessment to determine the tolerable dimensions of flaw indications at full encirclement repair sleeves. In particular, the project was intended to validate the stresses estimated using finite element analysis (FEA) models against actual in-service loading conditions experienced at reinforcing sleeves. The experimental work focused on the collection of full-scale experimental data describing pipe and sleeve strains for the following field and laboratory conditions: • Strains induced by sleeve welding, • Strains induced by pressurization of the sleeved pipe, • Strains induced by pressurization of the sleeved pipe and the annulus between the pipe and sleeve. Finite element models of the field and laboratory sleeved pipe segments were developed and subjected to the same applied loading conditions as the full-scale sleeved pipe segments. Comparisons of the measured strains against those estimated using FEA were completed to determine the ability of the models to predict the behaviour of the sleeved pipe segments. Comparisons were made to illustrate the relative strain levels and deformation trends, the accuracies of the strain predictions and trends in changes with pressure, the differences in behaviours between tight and loose fitting sleeves, and the effects of pressurizing the annulus between the pipe wall and sleeve. The analysis of the field data and FEA modeling predictions led to several conclusions regarding to use of numerical models for predicting sleeved pipe behaviour and weld flaw acceptance: • FEA results demonstrated behaviours that were consistent with full scale data, • Trends in the FEA predicted strains agreed with the full-scale data, • FEA models describing the effects of gaps between the pipe and sleeve and annulus pressurization agreed with field experience and engineering judgment, • Evaluation of the significance of root and toe flaws can be completed by extending the models validated in this work.

Design of the Full Scale Experiments for the Testing of the Tensile Strain Capacity of X52 Pipes With Girth Weld Flaws Under Internal Pressure and Tensile Displacement

2014 ◽  
Author(s):  
Celal Cakiroglu ◽  
Samer Adeeb ◽  
J. J. Roger Cheng ◽  
Millan Sen
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Internal Pressure ◽  
Tensile Strain ◽  
Oil And Gas ◽  
Full Scale ◽  
Element Analysis ◽  
Simultaneous Application ◽  
Strain Capacity ◽  
Tensile Strain Capacity

Pipelines can be subjected to significant amounts of tensile forces due to geotechnical movements like slope instabilities and seismic activities as well as due to frost heave and thaw cycles in arctic regions. The tensile strain capacity εtcrit of pipelines is crucial in the prediction of rupture and loss of containment capability in these load cases. Currently the Oil and Gas Pipeline Systems code CSA Z662-11 0 contains equations for the prediction of εtcrit as a function of geometry and material properties of the pipeline. These equations resulted from extensive experimental and numerical studies carried out by Wang et al [2]–[6] using curved wide plate tests on pipes having grades X65 and higher. Verstraete et al 0 conducted curved wide plate tests at the University of Ghent which also resulted in tensile strain capacity prediction methods and girth weld flaw acceptability criteria. These criteria are included in the European Pipeline Research Group (EPRG) Tier 2 guidelines. Furthermore Verstrate et al 0 introduced a pressure correction factor of 0.5 in order to include the effect of internal pressure in the tensile strain capacity predictions in a conservative way. Further research by Wang et al with full scale pipes having an internal pressure factor of 0.72 also showed that εtcrit decreases in the presence of internal pressure [10]–[15]. In their work, Wang et al presented a clear methodology for the design of full scale experiments and numerical simulations to study the effect of internal pressure on the tensile strain capacity of pipes with girth weld flaws [10]–[15]. However, there has been limited testing to enable a precise understanding of the tensile strain capacity of pipes with grades less than X65 as a function of girth weld flaw sizes and the internal pressure. In this paper the experimental setup for the testing of grade X52 full scale specimens with 12″ diameter and ¼″ wall thickness is demonstrated. In the scope of this research 8 full scale specimens will be tested and the results will be used to formulate the tensile strain capacity of X52 pipes under internal pressure. The specimens are designed for the simultaneous application of displacement controlled tensile loading and the internal pressure. Finite element analysis is applied in the optimization process for the sizes of end plates and connection elements. Also the lengths of the full scale specimens are determined based on the results from finite element analysis. The appropriate lengths are chosen in such a way that between the location of the girth weld flaw and the end plates uniform strain zones could be obtained. The internal pressure in these experiments is ranging between pressure values causing 80% SMYS and 30% SMYS hoop stress. The end plates and connection elements of the specimens are designed in such a way that the tensile displacement load is applied with an eccentricity of 10% of the pipe diameter with the purpose of increasing the magnitude of tensile strains at the girth weld flaw location. The results of two full scale experiments of this research program are presented. The structural response from the experiments is compared to the finite element simulation. The remote strain values of the experiment are found to be higher than the εtcrit values predicted by the equations in 0.

Probabilistic Structural Analysis of Railroad Subgrade Using Finite Element Analysis

2019 ◽  
Author(s):  
Asif Arshid ◽  
Ying Huang ◽  
Denver Tolliver
Keyword(s):  
Finite Element ◽  
Structural Analysis ◽  
Shear Failure ◽  
Probabilistic Method ◽  
Probabilistic Methods ◽  
Influential Factor ◽  
Element Analysis ◽  
3 Dimensional ◽  
Weather Changes ◽  
Granular Layers

The reliability of finite element (FE) based deterministic structural analysis of railroad trackbed has improved significantly due to ever increasing computational powers. However, the application of probabilistic methods to incorporate the material and geometric variabilities in these FE analyses is still profoundly underworked. In this study, the influence of variability in granular layers’ modulus and thicknesses values on the railroad subgrade performance have been investigated by applying probabilistic method and using a 3-dimensional FE based numerical trackbed model previously developed and validated by the authors’ research group. The influence of these factors is accounted for by changing their coefficients of variance (COV) while keeping their means constant. Preliminary results revealed that the variation in subgrade modulus is the most influential factor for subgrade performance, both in terms of progressive shear failure and excessive plastic deformations, followed by ballast modulus. Variations in depths, for the range studied, remained passive to the subgrade performance. The findings of this work is of particular significance in evaluating the subgrade performance while including the material and geometric variations, which may be caused by construction imperfections, weather changes, and/or rail operations.

scholarly journals Repeatability of Full-Scale Crash Tests and Criteria for Validating Simulation Results

1996 ◽  
Vol 1528 (1) ◽  
pp. 155-160 ◽  
Author(s):  
Malcolm H. Ray
Keyword(s):  
Finite Element ◽  
Full Scale ◽  
Crash Test ◽  
Test Results ◽  
Finite Element Analyses ◽  
Element Analysis ◽  
Acceleration Time Histories ◽  
Time Histories ◽  
Simulation Results ◽  
Crash Tests

A method of comparing two acceleration time histories to determine whether they describe similar physical events is described. The method can be used to assess the repeatability of full-scale crash tests and it can also be used as a criterion for assessing how well a finite-element analysis of a collision event simulates a corresponding full-scale crash test. The method is used to compare a series of six identical crash tests and then is used to compare several finite-element analyses with full-scale crash test results.

Numerical Analysis of Punching Shear Failure of Self-Compacting Fiber Reinforced Concrete (SCFRC) Ribbed Slabs

2019 ◽  
Vol 972 ◽  
pp. 93-98
Author(s):  
Nurulain Hanida Mohamad Fodzi ◽  
M.H. Mohd Hisbany
Keyword(s):  
Finite Element ◽  
Reinforced Concrete ◽  
Shear Failure ◽  
Nonlinear Finite Element ◽  
Fiber Reinforced Concrete ◽  
Punching Shear ◽  
Nonlinear Finite Element Method ◽  
Fiber Reinforced ◽  
Element Analysis ◽  
Abaqus Software

This paper deals with behavior and capacity of punching shear resistance for ribbed slabs produce from self-compacting fiber reinforced concrete (SCFRC) by application of nonlinear finite element method. The analysis will be achieved by using ABAQUS software. The nonlinear finite element analysis by ABAQUS will be compare with the experimental results. Results and conclusions may be useful for establishing recommendation and need to be acknowledged.

scholarly journals Design and Calibration of a 6-Component Balance on a Bicycle Steer

Proceedings ◽  
2018 ◽  
Vol 2 (8) ◽  
pp. 520
Author(s):  
Jordi D’hondt ◽  
Sien Dieltiens ◽  
Marc Juwet
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Present Article ◽  
Regression Method ◽  
Full Scale ◽  
Least Square ◽  
Element Analysis ◽  
Multiple Loads ◽  
Least Square Regression ◽  
Scale Error

The present article describes the methodology used to design and calibrate a 6-component balance. This balance is utilized in an instrumented bike measuring the forces applied on the handlebars. This instrumentation bike maps all riders induced loads. In the designing process, Finite Element Analysis was used. Calibrating the balance was done using the Least Square Regression Method which allows combining multiple loads during calibration and thus requires less samples. The balance operates with a maximum full scale error of 0.53%.

The Finite Element Analysis on Can Coiler of Gilling Machine

2012 ◽  
Vol 215-216 ◽  
pp. 837-841 ◽  
Author(s):  
Bin Lin ◽  
Xiao Fei Dong ◽  
Guan Wei Zhang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Coordinate System ◽  
Contact Analysis ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Comparison Of The Results ◽  
Distribution Of Stress ◽  
The Impact ◽  
Bearing Structure

This paper first analyzes the structure of can coiler to estimate the load of the internal bearing structure and then uses the Pro/e software to calculate the mass and centroid of the can coiler, in the same coordinate system to determine the load of the bearing. Next, the intensity of bearing under different conditions will be analyzed by using the ANSYS contact analysis module, from which the distribution of stress and size of extreme value can be observed. At last, the impact of load changes on the stress will be analyzed based on the comparison of the results.

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