Bao Shou Sun

The Research on the Microstructure Evolution Law of Cross Wedge Rolling Asymmetric Shaft-Parts Based on Parity Wedge

Microstructure evolution is an effective means to improve the mechanical properties of products, shaft parts formed by cross wedge rolling is not only the shape of the formed parts, but more importantly it improves the comprehensive mechanical properties of the products by deformation. Therefore, the paper sets up the coupled rigid-plastic finite element model with deformation-heat transfer-microstructure by using nonlinear finite element method, and this model is adopted to make simulation calculation for the forming techniques of asymmetric shaft parts of cross wedge rolling based on parity wedge, specifically analyzes the rule of dynamic recrystallization and grain size distribution in the asymmetric rolled parts. The results show that the grain in the wedging place of asymmetric shaft parts of cross wedge rolling based on parity wedge can be obviously refined, and the research results of this paper may provide theoretical foundation for further improving the quality and mechanical properties of asymmetric shafts parts of cross wedge rolling.

Injection Molding Process Parameter Optimization for Warpage Minimization Based on Uniform Design of Experiment

To optimize injection molding warpage, this paper applies the uniform design of experiment method to search for the optimal injection molding processing parameters. The warpage. simulation analysis is accomplished by emplying Moldflow software. The melt temperature, mold temperature, injection time and packing pressure are regarded as processing parameters, and processing parameters are optimized through establishing a regression equation, and the optimization result and influence factors are analyzed. The results show that uniform design of experiment can reduce number of experiments used effectively and the quality of the product is greatly improved by the optimization method.

Strain Rules of Cross Wedge Rolling Asymmetric Shaft-Parts Based on the Parity Wedge

The analysising of strain is the key factors to understand the forming mechanism of cross wedge rolling asymmetric shaft. due to the extrusion of dies and other external force, its interior,interactions can cause the relative position between the various parts. In order to study the deformation of workpiece at different degrees, pulling in the finite element strain field analysis, the strain of the analysis at deformation process is also a necessary precondition for forming and stress distribution. In this papre,By using Deform3D platform, the forming process of the cross wedge rolling on parity wedge asymmetric shaft is simulated. It is also to be analyzed the distribution and variation of the amount of strain in the rolling process, it shows that a cross-sectional and longitudinal section about the deformation characteristics of the strain fields, the results can achieve production of cross wedge rolling and provide important theoretical foundation to promote further cross-wedge rolling.

The Design of Dual-Box Pier Anti-Collision Device Based on Rubber Cushion

Ship anti-collision device with flexible box structure is a new protection to pier device. By simplifying the rubber cushion dual-box pier ship anti-collision device as elliptic physical model and by simplifying the elliptic rubber cylindrical air cushion as linear elastic spring element, this paper can build the relationships between torque equation, elliptic structure parameters and equivalent elastic coefficient under different loading force. When outer steel ring takes a small displacement translation, the reverse force is only related to parallel direction of displacement and has a linear relationship with displacement. Making an analysis on elastic response of translational-rotational device, it can be approximated as a pure rotation curve under certain conditions. And the equivalent elasticity coefficient is only related to translational-rotational joint effect. The results will help the flexible dual-box ship anti-collision device to apply.

Mechanism Research on Multi-Wedge Synchrostep Rolling Asymmetric Shaft-Parts by Cross-Wedge Rolling

Because most of the asymmetric shaft-parts have relatively large size in the axial direction, single-wedge cross-wedge rolling (CWR) exposes many imperfections, such as the huge roller, higher cost etc. The paper adopted finite element method (FEM) to simulate multi-wedge synchrostep CWR (MS-CWR) based on the typical asymmetric shaft-part, and gained its distribution and characteristics of stress and strain. In the knifing stage, the deformation of work piece only emerges on the local region, but in the stretching stage, most of regions are observed the deformation except two ends of the billet and the transition position between inner and outer wedge of multi-wedges. The results offer theoretical basis for promoting and applying MS-CWR technology on asymmetric shaft-parts.

Structural Optimization Design of Anti-Collision Sealing Cylindrical Rubber Cushion

At present, it is inconvenient for use due to huge volume of common inflatable rubber fender. This paper introduces a design of cylindrical rubber sealing cushion which can be applied to various occasions to protect ships, dock and pier facilities. The key of air cushion technique is that it can produce a large displacement to buffer deformation and to reduce the exchange of energy. It plays a role to increase the time of collision, and then reduces the force of collision. Meanwhile, it also has good ability to adapt the tilted contact and it can float on the water surface, etc. This paper makes a feasibility analysis and strength calculation by doing theoretical calculation, and then making a force-test simulation by using ANSYS software, and do some structure optimal design according to the results of finite element analysis.

Research on Force Parameter and Deformation Mechanism in the Cold Rolling of Bearing Inner Ring

In this paper, the simulation model of the cold rolling process of the deep groove bearing inner ring was established by using the finite element software Deform-3D. The numerical calculation of the model was made with different process parameters. The law of the influence the process parameters on the rolling force was analyzed. The deformation mechanism of the cold rolling process of the inner ring was revealed. The research indicated that the feed rate of idle roller had the greatest influence on the cold rolling process. Finally the experiment using the XS-50 precision CN ring rolling machine was carried on and a finished product of the inner ring of a better quality came out. It verified that the numerical simulation could provide theoretical basis for the practical production process.

Optimization of Process Parameters for Warpage Minimization on Injection Molding Thin-Walled Parts

In this paper, Taguchi experimental design method is applied, and injection molding CAE simulation analysis is conducted. Influence factors of warpage of products are analyzed. According to the results of ranking, influence factors of warpag are the packing pressure, packing time, melt temperature and mold temperature. The packing pressure is the most important influence factor. To get the best level combination of various factors, mixed level orthogonal experimental design is applied to the optimization. Optimal levels of combination process parameters are obtained and the quality of injection products is greatly improved.

Injection Molding Flow Simulation of Thin-Walled Slender Tube and Optimization of Combined Cavity

Thin-walled slender tubes are produced by injection molding, where there might be defects such as short shot, excessive warpage and uneven temperature distribution. In this paper, injection process analysis was carried out. The 3D modeling technology of Pro/E established a solid model of thin-walled slender tube. MPI (Moldflow Plastics Insight) was used for executing injection molding flow simulation. Gate location and gate number was optimized. Filling system and cooling system of the combined cavity was optimized by analysis of flow, cool and warp. The results can be used for supplying reliable data of mold designing and manufacturing, reducing the engineering mold trial time, decrease the manufacturing cost. The configuration and dimensions of the injection gate can be determined by the computer program before the molds are actually manufactured. The potential defects were forecasted. Therefore, the designers can quickly optimize the mold design.

Injection Molding Process Optimization of Multi-Objective Based on MUD-RBFNN-GA

The optimization algorithm of MUD-RBFNN-GA was proposed in this article. An injection molding process optimization model of multi-factor and multi-objective was also researched. The multiple uniform designs of experiment was applied to optimize the processing parameters. During this process, the RBF neural network was established, where the melt temperature, mold temperature and packing pressure were taken as the inputs, and warpage, area of air-traps and weld-line length as the outputs, and the Moldflow simulation analysis was used to obtain the output values. By combining the algorithm with genetic algorithm and global optimization in the networks, we can get the optimal process parameters. The results show that the multi-objective optimization based on MUD-RBFNN-GA is practically applicable, and it can reduce the molding defects effectively.