Support Bracket Research Articles

Static linear analysis for trusses structure for supporting pipes

This paper is a study about truss deformations. This truss is supporting a pipe, it can be a bridge, or another structure and can be necessary for protecting rivers. The truss is a welded structure modelled with Weldment Structural Members, which is often found in industrial constructions and it can be constructed in different shapes. In order to sustain a pipeline over a damaged area, some trusses structures were modelled. The pipeline is supported by some support brackets mounted on the truss nodes. Finite Element Analysis is a process which can predict deflection and stress on a structure, here on a truss. A finite element model is a complete idealization of the entire structural part, including the node locations, the elements, material properties, loads and boundary conditions. The purpose of this paper is to find the best form for trusses using SolidWorks and to avoid oversizing these structures.

The method for determining working resistance of advance support bracket in deep fully mechanized roadway based on Flac3D

Fully mechanized roadway is an area of high accident incidence, and the problem is more prominent with the increase of mining depth of coal resources. The advance support scheme put forward for fully mechanized mining roadway with self-moving support and anchor combined unit, and the configuration and working principle of support robot was explicated. A determination method on the working resistance of advance support bracket was proposed based on mechanical coupling model of surrounding rock-advance support brackets. Taking the geological conditions of the Qishan mine as an example, the process of analyzing and determining the working resistance of the advance support bracket was described using this method. An advance support bracket was designed using SolidWorks, and the working load was obtained based on numerical calculations. Then the stress and strain were analyzed using ANSYS. The results showed that the designed advance support bracket can withstand the corresponding top plate pressure. It provides a new method and thought for study and development of advance supporting equipment in deep fully mechanized roadway.

Preliminary experimental/numerical study for the vibration annoyance control of a windshield wiper mechanical system through a Synchronized Switch Shunt Resonator (SSSR) technology

The present work focuses on the study and analysis of vibrations generated by the electrical motor of a wiper system on its support bracket referring to an hatchback vehicle passenger car. In the electric motor of the wiper system there can be present an imbalance transmitting vibrations to the main body via the support bracket. In this paper, after a short resume of available synchronized switch shunt damping methods, a preliminary experimental evalu- ation of their potential performance on noise control of the wiper system is reported. After preliminary experimental measurements of dynamic vibration by the use of vibrometer la- ser both on the real hatchback car then in laboratory environment, a numerical model has been created to evaluate deformations of the support bracket for comparison with the expe- rimental data. This work realizes the preliminary numerical/experimental characterization activity to set up a new application of a control system based on a semi-active technique, called Synchronized Switch Shunt Resonator (SSSR).

Modeling and Calibration of the Orthogonality Deviation between the "X" and "Y" Axes of Coordinate Measuring Machines

The increase of the quality in a productive process allows reduction of costs besides adding value to the product. When manufacturing a product within the tolerances specified in the design it is possible to obtain a correct operation of this product, ensuring the minimum time of use and with a lower risk of early failure. In this sense, machines and equipments involved in the manufacturing and inspection processes must also maintain an acceptable quality of operation by knowing the errors present in the machine structure through the calibration, such as errors due to lack of orthogonality between the axes, caused by inaccurate assemblies. The calibration errors in these machines allow elaborate error compensation plans and thus improve the rate of flawless products in production. The objective of this paper was to identify the influence of errors due to a lack of orthogonality in a bridge type coordinate measuring machine (CMM) through calibration and mathematical modeling of errors. Error calibration is performed with a linear displacement transducer, a granite square and a set support brackets for the granite square. By means of the calibration data and the mathematical modeling of the orthogonality deviation an influence of the measured deviation on the "X" and "Y" directions of the CMM is obtained. The error due to the lack of orthogonality between the "X" and "Y" axes of the CMM was approximately 8.9558 negative arcoseg; in this way, it is evidenced that the angle formed between these axes is 89.9975°. Through this study it can be concluded that orthogonality deviation in the main plane of the machine produces negative components for the axes "X" and "Y", with higher influence on the points collected as it away from machine scales, making greater the error intensity on the results of measurements made at positions farthest from the "X" and "Y" scales.

Increasing the lifespan of high-pressure die cast molds subjected to severe wear

Regardless the increasingly incorporation of composite materials on vehicle components, high pressure die casting still remains one of the most useful manufacturing techniques to obtain automotive parts with a complex shape in a cost effective way. It is well known that automotive industry requires high production cadence as well as high products quality. Thus, systematic approaches are permanently being done leading to optimize all the production and management aspects.The aluminum alloys commonly used in automotive parts such as fuel pumps bodies, throttle bodies, EGR valves, support brackets and so on usually contain Silicon which presents high abrasively. The aluminum flow at high temperature and high speed into the mold induces severe wear, sometimes due to a combination of abrasion and erosion effects.In this study, two molds with typical severe wear problems were selected and the wear mechanisms involved were deeply studied. After that, a careful selection of the best coating for this purpose was done and some of the most critical parts of the mold were coated in order to test possible effective advantages of the coating application, analyzing the wear resistance behavior and wear mechanisms involved. In parallel, tribological tests were also carried out in order to study if a correlation between laboratory and industrial tests can be drawn. Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy were intensively used to characterize the coatings and the wear mechanisms observed. Laboratory tribological tests have involved ball scattering and block-on-ring tests, trying to impose low and medium loads on the contact, respectively. Promising results were obtained allowing conclude that certain coatings present a better behavior than other ones in this field of application.

Phased acoustic array measurements of a 5.75% hybrid wing body aircraft

Detailed acoustic measurements of the noise from the leading-edge Krueger flap of a 5.75% hybrid wing body aircraft model were acquired with a traversing phased microphone array in the Arnold Engineering Development Complex NFAC 40- by 80-foot wind tunnel. The spatial resolution of the array was sufficient to distinguish between individual support brackets over the full-scale frequency range of 100 to 2875 Hz. For conditions representative of landing and take-off configuration, the noise from the brackets dominated other sources near the leading edge. Inclusion of flight-like brackets for select conditions highlights the importance of including the correct number of leading-edge high-lift device brackets with sufficient scale and fidelity. These measurements support the development of a Krueger noise model which includes cove and bracket noise.

Design Consideration for Additive Manufacturing: Fused Deposition Modelling

Additive Manufacturing (AM) technologies have progressed in the past few years and many of them are now capable of producing functional parts instead of mere prototypes. AM provides a multitude of benefits, especially in design freedom. However, it still lacks industrial relevance because of the absence of comprehensive design rules for AM. Although AM is usually advertised as being the solution for all traditional manufacturing design limitations, the fact is that AM only replaces these limitations with a different set of restrictions. To fully exploit the advantages of AM, it is necessary to understand these limitations and consider them early during the design process. The establishment of design considerations in AM enables parts and process optimization. This paper discusses the design considerations that will lead to optimize part quality. Specifically, the work discusses the Fused Deposition Modeling (FDM) due to its common use and availability. These considerations are drawn from literature and from experiments done by the authors. The experiments done by the authors include an investigation for the influence of elevated service temperature on the performance of FDM PLA parts, benchmarking the capability of FDM to print overhangs and bridges without supports, studying the influence of processing parameters over dimensional accuracy, and the effect of processing parameters on the final FDM samples modulus of elasticity. The work presents a case study investigating the correct clearances for FDM parts and finally a redesign for AM case study of a support bracket originally manufactured using traditional manufacturing methods taking into consideration the design considerations discussed in this paper.

Bifilm defects in ductile-iron support bracket castings

Many filling defects such as bi-film defect, gas bubble, loosed sand and etc., are developed by turbulent filling. These defects entrapped and flowed along mold cavity during the filling process. As a result, they makes casting property unreliable and unpredictable. The best way to prevent the filling defect is to control the gating velocity under a critical value using a bottom gating runner system. Two different gating system, top- and bottom- systems, are applied for casting ductile-iron support bracket. For these two runner systems, their filling defects are predicted by a numerical modeling. Two- and three- parameter Weibull probability are plotted to analyze the reliabilities of the mechanical properties of the castings from these two gating systems. A good and reliable runner system for casting a high elongation and fracture toughness of the support bracket was proposed in this study.

Strength Analysis and Process Simulation of Subway Contact Rail Support Bracket of Composite Materials

An application of composites for construction of subway brackets is a very effective approach to extend their lifetime. However, this approach involves the necessity to prevent process-induced distortions of the bracket due to thermal deformation and chemical shrinkage. At present study, a process simulation has been carried out to support the design of the production tooling. The simulation was based on the application of viscoelastic model for the resin. Simulation results were verified by comparison with results of manufacturing experiments. To optimize the bracket structure the strength analysis was carried out as well.

Luggage Impact and Structure Optimization for Rear Seat Frame of Automobile

It is essential that the back seat of a vehicle has to be designed safely and reliably and at the same time meet the ECE R17, as to reduce the back seat casualties in accidents caused by luggage impact. This paper studies a sample of back seat frame and establishes its precise CAD model. It adopts nonlinear finite element methodology to simulate the object under the ECE R17. The results reflect two problems. One is the force absorption and anti-deformation of the split seat frame is too weak; the other is the fixed connections linking the frame to the holder is not tight enough causing easy fall-off if being shocked. The test and simulation results suggest the following alterations, respectively to substitute the previous split seat frame for a one-piece seat frame as to improve the overall stiffness and anti-deformation, to adopt one-piece structure on the center support bracket and increases its thickness by 0.5mm, keep the remaining mounting bracket structure unchanged. The analyses of the improved program demonstrate its superior anti-deformation under the regulations.

Effect of chemical compositions on tensile behaviors of high pressure die-casting alloys Al-10Si-yCu-xMn-zFe

Effects of chemical compositions on the tensile properties, deformation behavior and fracture mechanism have been studied in a die-casting aluminum alloys Al-10Si-yCu-xMn-zFe. The test specimens were taken from the engine support brackets and tested at 20°C, 150°C and 300°C. Addition of Mn and Cu elements in the Al-10Si alloys can significantly increase the YS and UTS of the alloys. The as-cast Al-10Si-1.5Cu-0.8Mn-0.15Fe alloy exhibits the highest tensile properties (RT: YS of 190MPa and UTS of 308MPa, 150°C: YS of 176MPa and UTS of 249MPa, 300°C: YS of 94MPa and UTS of 111MPa). Increasing test temperature reduces the YS and UTS and improves the ductility of the alloys. Chemical compositions (such as Mn, Cu and Fe) do not significantly affect the work-hardening behavior of the alloys. Increasing test temperature significantly decreases the n and k values. Phase particles (both Si and (Fe/Mn)-rich) cracking and debonding determine the fracture mechanism of the alloys. Final failure of the alloys mainly depends on the global instability (HT, necking) and local instability (RT, shearing).

Design assessment of triangular support bracket for manufacturability

The triangular support is connected structurally and hydraulically with the inner shell of the vacuum vessel and its main role is to keep plasma vertical stability during operational disruptions. Korea is responsible for the procurement of sectors 1 and 6 of the main vessel including triangular support. At present, design review for its fabrication by ITER Korea and Hyundai Heavy Industries, Co., Ltd. is in progress. This paper presents the results on various designs for triangular support bracket in terms of manufacturability considering both easiness of non-destructive evaluation and fabrication efficiency. The several designs are proposed and evaluated under the most critical loading condition using elastic and limit analysis with fatigue evaluation. Consequently, an optimized design for structural safety is determined in accordance with RCC-MR. This result is reconfirmed by cross-checking in comparison with the baseline of integrity that already had been determined by ITER Organization. The design deviation requests of triangular support bracket have been submitted to ITER Organization and Agreed Notified Body for approval, and their verification is currently under discussion.

Comparison of different heat transfer models for parabolic trough solar collectors

Abstract Parabolic trough solar collector (PTC) is one of the solar thermal energy applications, which focuses sunlight to heat the heat transfer fluid (HTF) circulating through the receiver. Researchers have put forward several heat transfer models for PTCs, basing on laws of conservation. This paper summarized the one-dimensional (1-D) mathematical models under different assumptions and details for PTCs. All the heat transfer processes were considered: convection within the absorber, in the annulus and between the glass and ambient; conduction through glass cover, absorber and support brackets; radiation in the annulus and from the glass to the sky. Moreover, a simple algorithm was adopted to make the control equations linear and solve easily. The difference in accuracy for diverse 1-D models were presented and analyzed on the basis of the experimental data from Sandia National Laboratories. The 1-D models with various details were different in accuracy and complexity. It can choose an appropriate 1-D model under a certain condition, which can be used in investigating the thermal performance of a PTC. In addition, the most accurate 1-D model presented in this paper were precise enough compared with the three-dimensional (3-D) model from other paper. The average difference of outlet temperature between the most accurate simulation in this paper and test data was 0.65 °C, however it was 2.69 °C between the 3-D model and experiment results. The reason may be that there were more assumptions for 3-D models than 1-D models, therefore the error was bigger.

大埋深高应力软岩巷道围岩支护技术研究

以深部软岩巷道为研究背景，对某矿西盘区底板措施巷巷道表面位移进行监测，监测结果表明巷道围岩出现非线性大变形、锚索破断及支架扭曲变形等现象。利用FLAC3D对巷道围岩进行数值模拟，得出软岩巷道围岩变形属于给定变形，巷道支护体不仅要提供足够的支护强度，还必须适应软岩巷道大变形，据此提出可接长锚杆协调支护技术，使稳定后顶板下沉量在200~250 mm之间，两帮相对移近量在200 mm上下，得到预期的支护效果。 In this study, the deep soft rock roadway was as the research background. The roadway of the mine’s west bottom panel measure’s lane surface displacement was monitored. Data show that the rock roadway deformation is nonlinear large deformation of surrounding rock deformation and widespread cable breakage and other support bracket distorted body damage phenomena. Using FLAC3D software to simulate on the rock roadway, we obtained that the deformation of soft rock roadway belonged to given deformation. Roadway body not only has to provide sufficient supporting strength, but also must adapt to large deformation of soft rock roadway. Hereby, proposing the coordinated supporting technology with docking bolt, making the roof sinkage between 200 and 250 mm when it is stable and the relative two sides moving quantity in 200 mm up and down, getting the expected supporting effect.

3D high lift flow computations using HiFUN

A summary of the results obtained using the flow solver HiFUN for the 3D High lift NASA Trapezoidal wing are presented. Hybrid unstructured grids have been used for the computations. Grid converged solution obtained for the clean wing and the wing with support brackets, are compared with experimental data. The ability of the solver to predict critical design parameters associated with the high lift flow, such as α max and $$C_{L_{max}}$$ is demonstrated. The utility of the CFD tools, in predicting change in aerodynamic parameters in response to perturbational changes in the configuration is brought out. The solutions obtained for the high lift configuration from two variants of the Spalart-Almaras turbulence model are compared. Inferences from the study on useful design practices pertaining to the 3D high lift flow simulations are summarized.

Thermal–structural analysis of ITER triangular support for dominant load verification

The triangular support is located on the lower inner shell of vacuum vessel of ITER, which should be designed to withstand various loads such as nuclear heat, coolant pressure and so on. The appropriateness of its design is evaluated under the dominant load that could represent the most conservative condition among the design loads. In order to decide the dominant load, a valid method for thermal–structural analysis is firstly verified considering contradictory behaviors between heat and structural loads.In this paper, two approaches; one-way coupling and load combination, are introduced for thermal–structural analysis. The one-way coupling is a method generally used but has a limit to apply on contradictory conditions. The load combination could give a proper solution since it evaluates each load independently and then adds up each result linearly. Based on the results of each case, structural analysis for another load case, baking condition with incident, is conducted to find out which load is dominant for triangular support.Consequently, it is found that the baking condition is the dominant load for triangular support bracket. The proposed load combination method gives a physically reasonable solution which can be used as a reference for checking the validity of other thermal–structural analysis. It is expected that these results could be applied for manufacturing design of the triangular support under various load conditions.

Overview and Summary of the Second AIAA High-Lift Prediction Workshop

The Second AIAA CFD High-Lift Prediction Workshop was held in San Diego, California in June 2013. The goals of the workshop continued in the tradition of the first high-lift workshop: to assess the numerical prediction capability of current-generation computational fluid dynamics technology for swept, medium-/high-aspect-ratio wings in landing/takeoff (high-lift) configurations. This workshop analyzed the flow over the DLR-F11 model in landing configuration at two different Reynolds numbers. Twenty-six participants submitted a total of 48 data sets of computational fluid dynamics results. A variety of grid systems (both structured and unstructured) were used. Trends due to grid density and Reynolds number were analyzed, and effects of support brackets were also included. This paper analyzes the combined results from all workshop participants. Comparisons with experimental data are made. A statistical summary of the computational fluid dynamics results is also included.

Metallurgical Failure Investigation of Minor Leakage in a Fuel Oil Return Line of a Combined Cycle Gas Turbine Engine

AbstractA small fuel oil return line of a stationary gas turbine engine failed by high cycle fatigue cracking. In the metallurgical root cause investigation, performed by the original equipment manufacturer's laboratory, it was determined that insufficient support of the fuel line and the ensuing vibration led to dynamic alternating bending stresses, that had their maximum immediately adjacent to the connector weld of the flange. The piping system was made of metastable austenitic stainless steels. Constraint in the system at the flange, geometric notches in the weld caused by root reinforcement and excess weld metal at the weld toe, were all determined to have been contributing factors. What is more, the unavoidable metallurgical notch represented by the heat affected zone (HAZ) of the weld joint with its coarse-grained microstructure, may also have contributed to the cracking. The root cause of the failure was a design problem, because sufficient pipe support was not specified. The primary cause of failure was assembly, where the missing supports were not realised to be a potential problem. The organisational cause of failure was insufficient training of design and assembly personnel. Finally, the metallurgical or physical cause of failure was fatigue. It was recommended to provide for additional support brackets in the affected pipe length, in order to prevent the fuel oil return line from vibrating excessively.

Welding of large support bracket components (Type V) of ship propeller shafts

We present the practical aspects of qualification of a welding procedure for the large-size structure of brackets of screw shafts made of cast steel and performance of a real welding operation. The issue of qualification of welding procedures, conducting assembly-welding works coupled with their monitoring and local heat treatment of welded joints as well as some aspects of non-destructive testing of welds are discussed. The whole work was supervised by Lloyd's Register of Shipping.

An improved installation for control moment gyros and its applications on reconfiguration and singular escape

A cluster of control moment gyros (CMGs) is widely used as the actuator of attitude control for modern satellite. However, to use CMGs will induce some accessional problems, like the singularity and the failure of them. In this paper, a rotator for the support bracket of each control moment gyro (CMG) is adopted and its application on reconfiguration and singular escape is discussed. The first step puts forward a novel reconfiguration scheme for the CMGs and applied on a satellite, which can adjust the installation angles of the remaining CMGs and make the CMGs remain axial symmetry. Then the characteristic of the output torque is studied in the process of reconfiguration of the CMGs. Based on this characteristic, a special steering law of the CMGs is designed to counteract the disturbance from the reconfiguration. The feasibility of singularity avoidance via the reconfiguration is also discussed by calculating the derivative of the singularity measurement to the installation angle. A singularity avoidance steering law is proposed based on the above calculation.