Finite-Element Analysis of the Load Factor and Design for Bolted Circular Flange Joints Consisting of Dissimilar Clamped Parts Under Tensile Loadings

Author(s):  
Shunichiro Sawa ◽  
Yasuhisa Sekiguchi ◽  
Toshiyuki Sawa

Abstract The load factor for bolted circular flange joints where two dissimilar material (steel-aluminum) of circular flanges are clamped by a lot of bolts and nuts under external tensile loadings is examined newly using Finite Element analysis. Furthermore, the effects of the bolt pitch circle diameter D and number of tightened bolts N on the load factor and a load when the interfaces start to separate are examined. The value of the load factor for steel-aluminum circular flange joint is a little bit larger than that for steel-steel circular flange joints and it increases as the value of D decreases. In addition, it decreases as the value of N increases. A maximum bending stress is also found newly about 5% larger than the bolt stress due to the load factor. The experiments to measure the load factor, the maximum bending bolt stress and a load when the interfaces start to separate were carried out. The FEM results are fairly coincided with the experimental results. Finally, based on the obtained load factor, a design method for bolted joints with dissimilar circular flanges is demonstrated for determining the nominal bolt diameter and the bolt strength grade and the effect of bolt number N is examined. It is found that the contact stress at the bearing surfaces of aluminum circular flange is critical and it is shown that washers are needed in some cases.

Author(s):  
Shunichiro Sawa ◽  
Yasuhisa Sekiguchi ◽  
Toshiyuki Sawa

In the present paper, the load factor for bolted T-shape flange joints where two dissimilar material (steel-aluminum) of T-shape flanges are clamped by two bolts and nuts under external tensile loadings is examined using Finite Element analysis. Furthermore, the effect of the distance C between the center of the bolt and that of T-shape flange on the load factor and a load when the interfaces start to separate are examined. In addition, the mechanical characteristics of bolted T-shape flange joints where two clamped parts are steel and aluminum are examined. The value of the load factor for steel-aluminum T-flange joint is a little bit larger than that for steel-steel T-flange joints. When the external tensile loads are applied to the bolted T-shape flange joints, the bolts are inclined and as a result, the bending moment occurs in the bolts. A maximum bending stress in the bolts is also shown and it is about 6% larger than the bolt stress due to the load factor. For verification of FEM calculations, experiments to measure the load factor and the maximum bending stress occurred in the bolts are carried out. The FEM results are in a fairly good agreement with the experimental results. Finally, based on the obtained results, a design method for bolted joints with dissimilar T-shape flanges is demonstrated for determining the nominal bolt diameter and the bolt strength grade. It is found that the contact stress at the bearing surfaces of aluminum T-flange is critical.


2011 ◽  
Vol 346 ◽  
pp. 379-384
Author(s):  
Shu Bo Xu ◽  
Yang Xi ◽  
Cai Nian Jing ◽  
Ke Ke Sun

The use of finite element theory and modal analysis theory, the structure of the machine static and dynamic performance analysis and prediction using optimal design method for optimization, the new machine to improve job performance, improve processing accuracy, shorten the development cycle and enhance the competitiveness of products is very important. Selected for three-dimensional CAD modeling software-UG NX4.0 and finite element analysis software-ANSYS to set up the structure of the beam finite element model, and then post on the overall structure of the static and dynamic characteristic analysis, on the basis of optimized static and dynamic performance is more superior double wall structure of the beam. And by changing the wall thickness and the thickness of the inner wall, as well as the reinforcement plate thickness overall sensitivity analysis shows that changes in these three parameters on the dynamic characteristics of post impact. Application of topology optimization methods, determine the optimal structure of the beam ultimately.


2020 ◽  
Vol 14 (5-6) ◽  
pp. 555-567
Author(s):  
Michael Weigelt ◽  
Cornelius Thoma ◽  
Erdong Zheng ◽  
Joerg Franke

AbstractNumerous applications of daily life use flat coils, e.g. in the automotive area, in solar technology and in modern kitchens. One common property that all these applications share, is a flat coil made of high-frequency (HF) litz wires. The coil layout and the properties of the HF litz wire influence the winding process and the efficiency of the application. As a result, the HF litz wire must meet the complex technical requirements of the winding process and of the preferred mechanical, electromagnetic and thermal properties of the HF litz wire itself. Therefore, a reasonable configuration and optimization of HF litz wire has been developed with the help of a finite-element-analysis (FEA). In this work, it is first shown that the mechanical behavior of HF litz wire under tensile and bending stress can be simulated. Since the computational effort for modelling an HF litz wire at the single conductor level is hardly manageable, a suitable modelling strategy is developed and applied using geometric analogous models (GAM). By using such a model, HF litz wires can be designed for the specific application and their behavior in a winding process can be predicted.


2013 ◽  
Vol 871 ◽  
pp. 347-351
Author(s):  
Dun Cai Lei ◽  
Jin Yuan Tang

A lecture on the method to compute the the stress of V-tooth coupling under the actual operating conditions. the finite element analysis model of V-tooth coupling under the preload, axial load and torsion was established by used of the software ABAQUS,and the distribution of the bending stress at the root was obtained. The analytical method to compute the bending stress of V-tooth disk is deduced based on the basic principle of material mechanics, and the relative error within 10% compared with the results of finite element analysis.The paper work provide the reference for the precision design of V-tooth coupling.


Author(s):  
Yasumasa Shoji ◽  
Toshiyuki Sawa ◽  
Hiroshi Yamanaka

As self-loosening of nuts is really a problem for bolted joints in practical use, countermeasures for the loosening is highly required. In this situation non-loosening fasteners are one of the resolutions for any fastened machinery as an essential mechanical element. Self-loosening of threaded bolt/nut systems has been researched in number of works and most researches were based on experiment and a few were based on the finite element analysis in these years. Using this new approach, various types of nuts can also be examined. Among these nuts eccentric nuts and slit nuts are especially expected to be the solution, as these nuts are reported to endure NAS vibration tests and were not loosened. In the authors’ previous paper, an eccentric nut and a normal nut were analyzed and compared in the aspect of loosening property. In this paper degree of loosening of various nuts was investigated by experiment and the FEA.


2014 ◽  
Vol 598 ◽  
pp. 194-197
Author(s):  
Hong Jun Li ◽  
Qiang Ding ◽  
Xun Huang

Stress linearization is used to define constant and linear through-thickness FEA (Finite Element Analysis) stress distributions that are used in place of membrane and membrane plus bending stress distributions in pressure vessel Design by Analysis. In this paper, stress linearization procedures are reviewed with reference to the ASME Boiler & Pressure Vessel Code Section VIII Division 2 and EN13445. The basis of the linearization procedure is stated and a new method of stress linearization considering selected stress tensors for linearization is proposed.


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