Papers by Author: Sheng Le Ren

Abstract: Rails is an affordable, fixed, direct the mobile device. Among the many factors that affect performance, the rail surface is a very important factor. This article use test method gets the static stiffness of joint surface and the top five bands of the natural frequency and damping ratio for small linear guides. Test access to the static stiffness will be important in finite element analysis of input parameters. In the course of the study, analysis of dynamic performance of small - scale test guide, Study on Effect of surface characteristics on the structure of the component. By comparing the small guide the results of the analysis and the experimental results to verify the validity and accuracy of the analysis method.

Abstract: The research on the combination of the characteristics becomes extremely important to the success of machine tool design. This paper mainly studies the dynamic and static characteristic parameters of heavy machine tool guide-way joint. And put forward a practical machine tool combining surface analysis method according to the experimental verification. It is presented that small linear guide as a scale model based on similarity theory. And make a research on the static and dynamic characteristics of small guide joint and the conclusion extended to heavy machine set of faces. And the conclusion is extended to the heavy machine set of faces. The results can be used as reference data about structure and design of the machine tool due to the similarity principle and error range.

Abstract: In view of the demands in multidisciplinary design optimization (MDO) of valve products, the MDO model for valves is established, which takes account of mechanical analysis, fluid mechanics analysis, thermal-mechanical coupled analysis and seismic analysis. On this basis, the MDO integrated system is constructed combined with some new techniques to solve the common and critical problems of optimal design of valves. The system takes interplay and coupling of each discipline into account, applies effective optimization strategy, information transmitting and concurrent design to get the synergistic effect produced by interaction of each discipline, and finally obtains the total optimum solution of valves, which, moreover, could provide technical reference for the practicality and commercialization of the integrated system in valves design optimization.

Abstract: The unloading spring-back of tubes during its manufacturing process shows a strong nonlinearity, which greatly influences the precision of parts. In this paper, the strain distribution of bending tubes was analyzed based on the elasto-plasticity theory, and the theoretical equation for spring-back of tubes was derived. The numerical simulation model for cold tube-bending process was developed with prediction error of 9% compared with experimental results, indicating high reliability of the model. The 12Cr1MoV and 20G tubes were used to analyze the effects of bending angle, bending radius and bending speed on the spring-back of tubes. The prediction equation of spring-back was built, which shows that the spring-back tendency was in accordance with theoretical analysis results. The simulated results show that the spring-back angle is linearly proportional to the bending angle within a certain range. In addition, it is proportional to the relative bending radius and the bending speed.

Abstract: The choice of the process parameters in the conventional tube bending forming is often based on experience. The method of constantly testing to adjust has seriously affected the production efficiency and increased production costs. In this paper, an intelligent prediction model of the tube bending forming process parameters for utility boiler was set up based on neural network, which has been used to predict the main process parameters including the bending moment and boost power. In the intelligent prediction model, the analytical calculations, numerical simulation and experimental data are selected as the source of training samples. The test results show that the average relative error between the simulation output and target output of bending moment and boost power is less than 2%, and the predicted process parameters, i.e. bending moment and boost power, can be directly used for actual production.

Abstract: A new type of torque sensor system used in torque rheometer is designed. Precision and reliability is analyzed by virtual prototyping simulation. Simulation shows that the system error increases with the backlash increasing. So the gearhead must have some certain precision demand. The torque sensor components are developed on the basis of simulation. The experiment shows that this measure system does not use active part, so it does not need to maintenance, and the reliability is high. The temperature and outside stress influence and hysteresis error are eliminated. The torque sensor system measure precision is better than 0.1% F.S.

Abstract: Quality control is very important in the manufacturing process of cold tube-bending, but most of enterprises can only verify tube quality by the tube bending machine. Based on the platform of commercial software, an integrated system on CAD/CAPP/CAE for bending tube in power plants boiler is developed. The system is carried on re-development under the VC++ language environment, and data is transferred in Pro/E, Ansys and designing module through a reasonable data structure and interface. So we can share data and realize flexibility and standardization of the processing. The application result indicated that the integrated system can offer a whole set of solution from building a CAD model, forecasting tube bending quality and structure optimization by CAE methods to programming CAPP processes.

Abstract: A FEM-numerical simulation system is developed to simulate the process of rotary draw bending of tube. The emphasis is to discuss some factors such as tube materials, bending moment of fan-shaped die, pushing force of sliding slot and tube relative bending radius which have an effect on tube bending quality. The quality parameters of ovality, thinning ratio and thickening ratio are the same as the measurement values in the practical production. Some improved methods are put forward to according to the simulation results. The experiment shows that the simulation system can forecast accurately the deformation in the process of tube bending, so the production manufacturing cost decreases greatly.

Abstract: As an important factor in composite fiber winding, fiber winding tension influences the product quality directly, and therefore tension control is a key technique in fiber winding techniques. This paper introduces a closed loop tension control system with the PIC single chip computer as the kernel, a function module with TLC5615 D/A converter as the output, AC servomotors as the actuator, and a radius-following arm to measure the real time radius of the scroll. The mechanism of the tension control system is analyzed and the mathematical model is set up. Then the paper expatiates the design of main control circuit, the voltage transformation circuit and the analogy filter circuit. In addition, the paper presents digital filter and control algorithm of the PIC software. The system is proved to have high control precision and rapid time response through performance experiments of the tension control system in different working states, which well meets the anticipated design requirements.