Advanced Materials Research Vols. 538-541

Abstract: The paper presents a new method which uses Binary Tree SVM in the automatic classification of surface defects for hot strip. Two types of Binary Tree SVMs are applied in defect classification. Compared with BP neural network and one-against-one SVM, the algorithm adopted in the paper greatly improved the accuracy of classification and decreased the classification time.

Abstract: A triplex plunger pump used for activating the journal bearing in cold rolling machine, could work only for one week comparing with the design life for two years in normal condition. The valve seat of the pump, which is made from 42CrMo4, was corroded on its exterior surface and plowed on its seal face. Since this failure, the pump could not work in its operating pressure. By evaluation and numerical simulation of the pump, results indicate that the failure occurred because of crevice corrosion and cavitation corrosion on seat surface and seal face, respectively. The reason to cause the corrosion was clarified and corresponding measures were put forward. Hence, the pump works in a normal condition.

Abstract: The yarn production is a complex industrial process, and the relation between the spinning variables and the yarn properties has not been established conclusively so far. In fact, the existing process cases which were recorded to ensure the ability to trace production steps can also be used to optimize the process itself. This paper presents a novel process decision model based on CBR and SVM hybird intelligence for optimization of large numbers of spnning parameters. The applied cases are demonstrated that the intelligent model to optimizing the spinning process is promising.

Abstract: Abstract: Aiming at such performance indexes in fused deposition modeling (FDM) as dimensional error (DE) and warpage deformation (WD), and selecting four process parameters, wire-width compensation (A), extrusion velocity (B), filling velocity (C), and layer thickness (D), as controlling factors, this paper optimized the four process parameters by means of Taguchi method combined with fuzzy comprehensive evaluation. The optimization results show that the parameter with the most significant influence on the performance indexes is A, followed by B, D, and C, and that the optimum combination of the process parameters is A1B1C2D3.

Abstract: The aim of this study is to evaluate the effects of two nonlinear kinematic hardening models on springback prediction of dual phase steel. Young’s modulus degradation with plastic strain was also considered. Material parameters of both hardening models were identified by fitting the experimental tension-compression-tension stress-strain curves using optimization software LS-OPT. The results showed that the nonlinear kinematic hardening models gave good prediction compared with measured data. And a 2-D draw-bend springback benchmark was applied to assess the material models with identified parameters. The accuracy of springback simulation improved when both kinematic hardening and Young’s modulus degradation were considered. Yoshida model gave the best overall springback prediction in the draw-bend springback of dual phase steel.

Abstract: The plastic state of simply supported beam loaded by the uniformly distributed load was studied. When its material models are bilinear hardening material model and exponential hardening material model, its maximum limit model was established. Moreover, the critical curve model of the theoretical model of plastic zone was established. Furthermore, through comparing the finite element analysis results with the theoretical analysis results, the theoretical models established in the paper was verified.

Abstract: Soft rock has a strong rheology behavior and displays different creep process under the different stresses. According the experimental data from the sandstone creep test, firstly the paper fitted and compared several different creep models, got the optimized sandstone creep model under the condition of low stresses, finally the paper determined its model parameters under the condition of different pH and differential stresses with the program of MATLAB who have certain reference value.

Abstract: Aiming at a cross-flow fan used in some kind of air conditioner, the full field 3D model was built, and the numerical simulation of the inner turbulent flow under design condition is resented. The results display the characteristics of flow field in the cross-flow fan, especially the velocity field, pressure field and the velocity distributing before the evaporator. The results can provide basis for optimizing the fan design and the internal flow, and have important value of engineering applications in the increase of the overall performance in operation.

Abstract: In manufacturing industry investors are always looking for economical and safe designs to cope up with the increasing demands of competitive markets. Keeping this objective in mind, arm of CE125 face shovel hydraulic excavator was re-designed to decrease manufacturing cost by reducing weight while keeping the stress approximately same as was used in the conventional design. For this purpose Pro/EngineerTM was used to generate Computer Aided Drawing (CAD) where cross section and inner structure of the design were kept to be semi-elliptical which helped to decrease the weight of the arm significantly. Initial stress analysis was also done in the same CAD software as it is quick and optimization can be done quickly. However sometimes it does not give accurate results because of poor meshing, so final analysis was done in AnsysTM. Analysis in AnsysTM calculated the stress to be 114 MPa while displacement came out to be 3.8 mm. Comparison of two models showed that the weight of new design is 5.1% less than the conventional one.

Abstract: According to the nutation movement of a rotating coin on a table, a novel nutation drive with rolling teeth is presented on the basis of oscillating teeth gear transmission. Firstly, the structure of mechanism is provided and transmission theory is declared. The formulae for calculating the transmission ratio of the mechanism is developed. Secondly, the modeling of this nutation drive is built. Finally, the results of theoretical calculations are verified by dynamic motion simulation of the prototype mechanism. In addition, Numerical control(NC) simulation of machining the stator and the rotor gears is developed.