A Method for Creating a Manufacturing Cost Heatmap Based Purely on Part Geometry

2018 ◽  
Author(s):  
Kelly A. Fox ◽  
Brandon Massoni ◽  
Matthew I. Campbell
Keyword(s):  
3D Printing ◽  
High Impact ◽  
Von Mises Stress ◽  
Manufacturing Cost ◽  
Cost Models ◽  
Part Geometry ◽  
Computer Aided ◽  
Solid Part ◽  
Metal 3D Printing ◽  
Von Mises

It is now common for computer-aided engineering tools to show a performance parameter — like von Mises stress — over the surface of a solid part. In this paper, a heatmap is generated for part cost where high values (shown in red) indicate regions with a high impact on manufacturing cost. This is accomplished by slicing the provided part many times in multiple orientations and evaluating the total costs of each side of the part at each slice. The costs from all the directions considered are combined to generate a heatmap to show how different regions affect cost, enabling the designer to make informed improvements to the part geometry. In this paper, our method for generating these heatmaps is presented with three primary manufacturing cost models: bar stock, forging, and metal 3D printing. In all cases, a machining operation is then applied to get to the final part shape. Results are shown to validate the approach and demonstrate its usefulness.

Thermal-Mechanical Study of 3D Printing Technology for Rail Repair

2018 ◽  
Author(s):  
Ershad Mortazavian ◽  
Zhiyong Wang ◽  
Hualiang Teng
Keyword(s):  
Thermal Analysis ◽  
Thermal Expansion ◽  
3D Printing ◽  
Stress Distribution ◽  
Temperature Gradient ◽  
Initial Temperature ◽  
Mechanical Analysis ◽  
Von Mises Stress ◽  
Additive Materials ◽  
Von Mises

The complicated steel wheel and rail interaction on curve causes side wear on rail head. Thus, the cost of maintenance for the track on curve is significantly higher than that for track on a tangent. The objective of this research is to develop 3D printing technology for repairing the side wear. In this paper, the study examines induced residual thermal stresses on a rail during the cooling down process after 3D printing procedure using the coupled finite volume and finite element method for thermal and mechanical analysis respectively. The interface of the railhead and additive materials should conserve high stresses to prevent any crack initiation. Otherwise, the additive layer would likely shear off the rail due to crack propagation at the rail/additive interface. In the numerical analysis, a cut of 75-lb ASCE (American Society of Civil Engineers) worn rail is used as a specimen, for which a three-dimensional model is developed. The applied residual stresses, as a result of temperature gradient and thermal expansion coefficient mismatch between additive and rail materials, are investigated. At the beginning, the worn rail is at room temperature while the additive part is at a high initial temperature. Then, additive materials start to flow thermal energy into the worn rail and the ambient. The thermal distribution results from thermal analysis are then employed as thermal loads in the mechanical analysis to determine the von-Mises stress distribution as the decisive component. Then, the effect of preheating on residual stress distribution is studied. In this way, the thermo-mechanical analysis is repeated with an increase in railhead’s initial temperature. In thermal analysis, the temperature contours at different time steps for both the non-preheated and preheated cases indicate that preheating presents remarkably lower temperature gradient between rail and additive part and also represents a more gradual cooling down process to allow enough time for thermal expansion mismatch alignment. In mechanical analysis, the transversal von-Mises stress distribution at rail/additive interface is developed for all cases for comparison purposes. It is shown that preheating is a key factor to significantly reduce residual stresses by about 40% at all points along transversal direction of interface.

scholarly journals Fracture Resistance of Monolithic Zirconia Crowns in Implant Prostheses in Patients with Bruxism

Materials ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1623 ◽  
Author(s):  
Ting-Hsun Lan ◽  
Chin-Yun Pan ◽  
Pao-Hsin Liu ◽  
Mitch M. C. Chou
Keyword(s):  
Cyclic Loading ◽  
Computer Aided Design ◽  
Fracture Resistance ◽  
Testing Machine ◽  
Von Mises Stress ◽  
High Fracture ◽  
Computer Aided ◽  
Zirconia Crowns ◽  
Monolithic Zirconia ◽  
Von Mises

The aim of this study is to determine the minimum required thickness of a monolithic zirconia crown in the mandibular posterior area for patients with bruxism. Forty-nine full zirconia crowns, with seven different occlusal thicknesses of 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.0 mm, were made by using a computer-aided design/computer-aided manufacturing system (CAD/CAM). Seven crowns in each group were subjected to cyclic loading at 800 N and 5 Hz in a servohydraulic testing machine until fracture or completion of 100,000 cycles. Seven finite element models comprising seven different occlusal thicknesses of 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.0 mm were simulated using three different loads of vertical 800 N, oblique 10 degrees 800 N, and vertical 800 N + x N torque (x = 10, 50, and 100). The results of cyclic loading tests showed that the fracture resistance of the crown was positively associated with thickness. Specimen breakage differed significantly according to the different thicknesses of the prostheses (p < 0.01). Lowest von Mises stress values were determined for prostheses with a minimal thickness of 1.0 mm in different loading directions and with different forces. Zirconia specimens of 1.0 mm thickness had the lowest stress values and high fracture resistance and under 800 N of loading.

scholarly journals The Conical Stones Olive Oil Mill: Analysis through Computer-Aided Engineering

Agriculture ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 255 ◽  
Author(s):  
José Ignacio Rojas-Sola ◽  
Eduardo De la Morena-De la Fuente
Keyword(s):  
Olive Oil ◽  
Computer Aided Engineering ◽  
Operating Conditions ◽  
Frame Structure ◽  
Von Mises Stress ◽  
Maximum Displacement ◽  
Safety Coefficient ◽  
A Value ◽  
Computer Aided ◽  
Von Mises

This article analyzes an olive oil mill formed of four conical stones used in the milling of the olive. To this end, a study of computer-aided engineering (CAE) was carried out using the parametric software Autodesk Inventor Professional, consisting of a static analysis using the finite-element method (FEM) of the three-dimensional (3D) model of the mill under real operating conditions. The results obtained revealed that the conical stones mill was a very robust machine. When studying the assembly in the most unfavorable situation (blockage of one of its millstones), we observed that the element with the highest von Mises stress was the bearing nut, reaching a value of 263.9 MPa, which was far from the elastic limit of cast iron (758 MPa). On the other hand, the machine hardly presented any equivalent deformations or displacements that could jeopardize the operation as a whole. The maximum displacement obtained was 2.494 mm in the inertia flywheel, and the equivalent deformations did not reach 0.1% of the part dimension. Similarly, the element with the lowest safety coefficient (2.87) was the same bearing nut with the highest von Mises stress, although the next element with the second lowest safety coefficient had a value of 8.69, which showed that the set was clearly oversized. These results demonstrate the convenience of redesigning the set in order to resize some of its elements, and that they could have lower safety coefficients of between 2 and 4. After an initial analysis, the resizable elements would fundamentally be those related to the movement transmission system and the frame structure.

Evaluation of failure of a titanium conventional plate in mandibular reconstruction and improve the performance with fibula free flap

2020 ◽  
Author(s):  
Sahand Kargarnejad ◽  
Farzan Ghalichi
Keyword(s):  
Cortical Bone ◽  
Free Flap ◽  
Computer Aided Design ◽  
Mandibular Reconstruction ◽  
Von Mises Stress ◽  
Fibula Free Flap ◽  
Computer Aided ◽  
Conventional Plate ◽  
Von Mises ◽  
Clinical Experiments

Maxillofacial extensive defects are caused by various factors such as tumor, osteomyelitis and trauma. Reconstruction of such injuries become a major challenge for maxillofacial surgeons. Clinical experiments indicate that one of the serious problems associated with conventional plate systems is the frequent incidence of complications such as screw loosening, plate exposure and plate fractures. To improve the performance of reconstruction system with new procedure. A 42-year-old male patient suffering from Ameloblastoma tumor in the lateral large defect was selected as case study. Initially, after cutting the cancerous tissue, a titanium conventional plate (TCP) model had been utilized as mandibular reconstruction system which failed due to plate exposure. Patient's CT-scan images were prepared, and geometry and shape of the plate were evaluated using Computer-Aided Design & Computer-Aided Manufacturing (CAD/CAM) and Additive Manufacturing (AM) technology. Then, its effect on the biomechanical performance of the failed system TCP model was investigated by finite element method (FEM). Fibula Free Flap FFF model as alternative and improved reconstruction system was selected. FEM evaluation of two models showed inevitable results which tip the scales in the favor of FFF model. The maximum Von-Mises stress had been exerted at the interface between screw-cortical bone. In TCP model, the peak value of Von-Mises stress exerted at the interface between screw-bone was 110 MPa, which exceeded the yield strength of the cortical bone, while, this factor fell to 68 MPa in FFF model. Furthermore, comparison with TCP model, the sensitivity of the plates and screws to the chewing load variations in FFF model decreased 20%. The results showed that the FFF model was more stable and flexible than the TCP model.

Design and analysis of biomimetics based excavator bucket and tooth

2021 ◽  
pp. 095440892110576
Author(s):  
Alkın Yılmaz Akter ◽  
Hudayim Basak
Keyword(s):  
Static Analysis ◽  
Equivalent Stress ◽  
Von Mises Stress ◽  
Total Deformation ◽  
Excavator Bucket ◽  
Soil Model ◽  
Computer Aided ◽  
American Badger ◽  
Von Mises ◽  
Digging Efficiency

Within the scope of this paper, various bucket tooth designs and a biomimetic bucket design were created in order to produce a solution on digging efficiency which is one of the general problems of construction machines. These designs were inspired by giant anteater and American badger front claws. The inspiration aspect was diversified by integrating the paw and claw curves of the giant anteater and by bringing American badger claws into the design in different ways. Furhermore, the designed biomimetic bucket alternatives were compared between each other and the standard bucket equipment used in the market by making a computer aided static analysis. The compared criteria were the equivalent stress and total deformation formed on the bucket itself, the excavation equipment and the excavated soil. According to the analysis results, when the bucket tooth named P2 is mounted to the standard bucket, it has 42% lower Von-Mises stress on than standard bucket tooth. Additionally, it is exposed 4,7% less total deformation than standard tooth. Also, in terms of maximum Von-Mises stress formed on the soil model, P2 causes 17,5% greater stress than the standard bucket tooth.

scholarly journals The Tower Press for Obtaining Olive Oil: Analysis through Computer-Aided Engineering

Agriculture ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 554
Author(s):  
José Ignacio Rojas-Sola ◽  
Eduardo De la Morena-De la Fuente ◽  
Manuel Jesús Hermoso-Orzáez ◽  
David Hernández-Díaz
Keyword(s):  
Olive Oil ◽  
Static Analysis ◽  
Computer Aided Engineering ◽  
Operating Conditions ◽  
Von Mises Stress ◽  
Screw Thread ◽  
Maximum Displacement ◽  
Safety Coefficient ◽  
Computer Aided ◽  
Von Mises

This article analyzes a large tower press used to press crushed olives to obtain olive oil. To this end, a study of computer-aided engineering (CAE) was carried out using the parametric software Autodesk Inventor Professional, consisting of a static analysis using the finite-element method (FEM) of the 3D model of the press under real operating conditions. The tower press has been analyzed in two limit positions: in the rest position, supported on two pillars, and the pressing position, supported on the set of filter discs (basket load) called ‘cargo de capachos’ that contained the previously ground olives. In the first position, static analysis revealed that the maximum von Mises stress was 22.7 MPa, located on the axle of the roller, but this is far from the elastic limit. Moreover, the lowest safety coefficient is 11.16, produced in the contact between the tower and the right pillar and well above the optimal range between 2 and 4. On the other hand, it hardly presents equivalent displacements or deformations that would endanger the operation of the set. The greatest displacement would be in the wooden guide (0.123 mm) and a deformation of 0.027% with respect to its length. These values confirm that, in this position, the tower press was clearly oversized. However, the results obtained regarding the second position are not entirely conclusive. Although the values of the displacements and the equivalent deformations are low, with results similar to those obtained in the first position, with a maximum displacement of 0.1315 mm located in the horizontal beam of the support structure and a maximum equivalent deformation of value 0.385%, located in the contact between the screw and the nut, the same does not happen with the von Mises stress. The software did not obtain a convergent result due to the frustoconical geometry of the bolt that joins the screw and nut, adopting a maximum value of 508.3 MPa. For this point, the safety coefficient is 1.49, which reveals a sizing problem with the proposed solution of resizing the screw thread, giving it more robustness. The rest of the elements work with a safety coefficient above 4.33 so they are also clearly oversized, according to current criteria.

scholarly journals The Hay Inclined Plane in Coalbrookdale (Shropshire, England): Analysis through Computer-Aided Engineering

2019 ◽  
Vol 9 (16) ◽  
pp. 3385 ◽  
Author(s):  
José Rojas-Sola ◽  
Eduardo De la Morena-De la Fuente
Keyword(s):  
Elastic Limit ◽  
Computer Aided Engineering ◽  
Operating Conditions ◽  
Von Mises Stress ◽  
Inclined Plane ◽  
Maximum Displacement ◽  
Emergency Braking ◽  
Maximum Value ◽  
Computer Aided ◽  
Von Mises

This article analyzes the ‘Hay inclined plane’ designed by the English engineer and entrepreneur William Reynolds and put into operation in 1792 to facilitate the transport of vessels between channels at different levels using an inclined plane. To this end, a study of computer-aided engineering (CAE) was carried out using the parametric software Autodesk Inventor Professional, consisting of a static analysis using the finite-element method (FEM) of the 3D model of the invention under real operating conditions. The results obtained after subjecting the mechanism to the two most unfavorable situations (blockage situation of the inertia flywheel and emergency braking situation) indicate that, with the exception of the braking bar, the rest of the assembly is perfectly designed and dimensioned. In particular, for the blockage situation, the point with the greatest stress is at the junction between the inertia flywheel and the axle to which it is attached, the maximum value of von Mises stress being at that point (186.9 MPa) lower than the elastic limit of the cast iron. Also, at this point the deformation is very low (0.13% of its length), as well as the maximum displacement that takes place in the inertia flywheel itself (22.98 mm), and the lowest safety factor has a value of 3.51 (located on the wooden shaft support), which indicates that the mechanism is clearly oversized. On the other hand, the emergency braking situation, which is technically impossible with a manual operation, indicates that the braking bar supports a maximum von Mises stress of 1025 MPa, above the elastic limit of the material, so it would break. However, other than that element, the rest of the elements have lower stresses, with a maximum value of 390.7 MPa, and with safety factors higher than 1.7, which indicates that the mechanism was well dimensioned.

scholarly journals Agustín de Betancourt’s Double-Acting Steam Engine: Analysis through Computer-Aided Engineering

2018 ◽  
Vol 8 (11) ◽  
pp. 2309 ◽  
Author(s):  
José Rojas-Sola ◽  
Eduardo De la Morena-De la Fuente
Keyword(s):  
Industrial Revolution ◽  
Computer Aided Engineering ◽  
Point Of View ◽  
Operating Conditions ◽  
Steam Engine ◽  
Von Mises Stress ◽  
Industrial Archaeology ◽  
3D Cad ◽  
Computer Aided ◽  
Von Mises

This article analyses the double-acting steam engine designed by Agustín de Betancourt in 1789 and based on the steam engine of James Watt. Its novelty and scientific interest lies in the fact that from the point of view of industrial archaeology and the study of technical historical heritage there is no worldwide study on this invention, which marked a historic milestone in the design of the steam engines of the Industrial Revolution (1760–1840). This underscores the utility and originality of this research. To this end, a study of computer-aided engineering (CAE) was carried out using the parametric software Autodesk Inventor Professional, consisting of a static analysis using the finite-element method of the 3D CAD model of the invention under real operating conditions. The results have shown that the double-acting steam engine was correctly designed considering that the values of the maximum von Mises stress (188.4 MPa) obtained were taken away from the elastic limit of the material it was made of (cast iron), as well as to the maximum deformations (0.14% with respect to its length) obtained in the same element that presents the maximum stress (opening axle of the high pressure steam valve). Similarly, the maximum displacements (18.74 mm) are located in the mobile counterweights that transmit certain inertia to facilitate the opening and closing of the valves. Finally, if we look at the results of the safety coefficient, whose lowest value was 4.02, we could say that the invention was oversized, following constructive criteria of the time, as there were no resistance tests on materials that would help in the optimization of the design of the invention.

Effects of occlusal scheme on All-on-Four abutments, screws and prostheses: A three-dimensional finite element study

2020 ◽  
Author(s):  
Nurullah Türker ◽  
Hümeyra Tercanlı Alkış ◽  
Steven J Sadowsky ◽  
Ulviye Şebnem Büyükkaplan
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Good Prognosis ◽  
Von Mises Stress ◽  
Element Analysis ◽  
Group Function ◽  
Occlusal Contact ◽  
Maximum Deformation ◽  
Contact Points ◽  
Von Mises

An ideal occlusal scheme plays an important role in a good prognosis of All-on-Four applications, as it does for other implant therapies, due to the potential impact of occlusal loads on implant prosthetic components. The aim of the present three-dimensional (3D) finite element analysis (FEA) study was to investigate the stresses on abutments, screws and prostheses that are generated by occlusal loads via different occlusal schemes in the All-on-Four concept. Three-dimensional models of the maxilla, mandible, implants, implant substructures and prostheses were designed according to the All-on-Four concept. Forces were applied from the occlusal contact points formed in maximum intercuspation and eccentric movements in canine guidance occlusion (CGO), group function occlusion (GFO) and lingualized occlusion (LO). The von Mises stress values for abutment and screws and deformation values for prostheses were obtained and results were evaluated comparatively. It was observed that the stresses on screws and abutments were more evenly distributed in GFO. Maximum deformation values for prosthesis were observed in the CFO model for lateral movement both in the maxilla and mandible. Within the limits of the present study, GFO may be suggested to reduce stresses on screws, abutments and prostheses in the All-on-Four concept.

The Influence of Loading Position in A Priori High Stress Detection using Mode Superposition

2020 ◽  
Vol 1 (1) ◽  
pp. 93-102
Author(s):  
Carsten Strzalka ◽  
◽  
Manfred Zehn ◽  
Keyword(s):  
Finite Element ◽  
Degrees Of Freedom ◽  
Equations Of Motion ◽  
A Priori ◽  
High Stress ◽  
Von Mises Stress ◽  
Detailed Knowledge ◽  
Variable Loading ◽  
Numerical Effort ◽  
Von Mises

For the analysis of structural components, the finite element method (FEM) has become the most widely applied tool for numerical stress- and subsequent durability analyses. In industrial application advanced FE-models result in high numbers of degrees of freedom, making dynamic analyses time-consuming and expensive. As detailed finite element models are necessary for accurate stress results, the resulting data and connected numerical effort from dynamic stress analysis can be high. For the reduction of that effort, sophisticated methods have been developed to limit numerical calculations and processing of data to only small fractions of the global model. Therefore, detailed knowledge of the position of a component’s highly stressed areas is of great advantage for any present or subsequent analysis steps. In this paper an efficient method for the a priori detection of highly stressed areas of force-excited components is presented, based on modal stress superposition. As the component’s dynamic response and corresponding stress is always a function of its excitation, special attention is paid to the influence of the loading position. Based on the frequency domain solution of the modally decoupled equations of motion, a coefficient for a priori weighted superposition of modal von Mises stress fields is developed and validated on a simply supported cantilever beam structure with variable loading positions. The proposed approach is then applied to a simplified industrial model of a twist beam rear axle.

Sign in / Sign up

Export Citation Format

Share Document