Papers by Author: Song Mei Yuan

Abstract: In order to estimate and optimize the static and dynamic characteristics of machine tool, the full parameterized FEM model of it is established and studied in the paper. After the FEM analysis of bed, this paper takes a machine bed as example, presents a method of combination of BP Neural-Network(NN) and Genetic-Algorithm(GA) to optimize dynamic characteristics and realizes the structural optimization of the bed. It proved that this method takes less time, and more precision compared to traditional method.

Abstract: Application of turn-milling technology in aviation is investigated in this paper. First, consideration is given to the characteristics and machining tools of turn-milling technology. Second, the paper describes, in detail, the application of turn-milling technology in the aviation industry: Include crankshaft, integrated impeller and aviation system part. And then, the actual machining experiment of aircraft landing gear part is conducted by applying turn-milling technology. The experiment shows that surface roughness of the landing gear part is improved from Ra>1um to 0.3 um Ra and the machining efficiency is enhanced by 200% compared with conventional processing method. Finally, in accordance with the machining experiments, the prominent application advantages of the turn-milling in aviation are expounded. Besides, the application prospect of the turn-milling in the aviation industry is forecasted and six proposals are put forward.

Abstract: This paper presents a generalized simulation algorithm for cutting forces prediction of helical milling. Calculating cutting thickness and the transition of coordinate system are the key points. The average cutting coefficient model is adopted. The simulation algorithm and related software are developed. It can predict cutting forces for inner and outer circle of helical milling. The validation and accuracy of the simulation algorithm has been verified by experiments.

Abstract: A dynamic characteristics test and analysis system for CNC machine tool is developed based on C++/Qt platform and NI-DAQmx data acquisition driver. The function modules include hammer experiment, signal continuous acquisition, spectral analysis, frequency response function analysis and signal coherence analysis, etc. The analysis results provide the basis of dynamics characteristics simulation and cutting parameters optimization. The system can be also used to analysis the vibration of the cutting process. Spectrum analysis modules help to assess the cutting stability and diagnose problems. Experiments show that the system has good accuracy and efficiency while the size and price are decreased compare with traditional equipment.

Abstract: Stricter environmental regulations are making the use of an ample amount of conventional coolant impossible because of its negative impact on the environment. Consequently, the use of minimum quantity lubrication (MQL) has been regarded as an promising alternative to conventional fluid coolant applications. Despite several studies, there have been a few investigations about the influence of the MQL nozzle position, such as distance from tool-workpiece contact zone, elevation angles, the included angle between jet direction and feed direction. The current study presents experimental investigations on influences of the above parameters on performance in end milling. Tool wear and surface roughness are experimentally studied to compare the effects of different positions. The results show that the setting location of the nozzle is an important factor regarding the effective application of MQL oil mist.

Abstract: This paper introduces simply concept and characteristic of turn-milling technology, including turn-milling machining centers and turn-milling process. Detailed describe present situation of turn-milling technology. Brief introduce several application examples of turn-milling technology. Finally, combined with the latest applications of turn-milling technology, discusses development of turn-milling technology, given the 8 direction.

Abstract: This paper presents experimental investigations on influences of cooling air temperature, as well as cutting velocity, on performance in milling of the 1Cr18Ni9Ti alloy with coated cemented carbide inserts. Cutting force, tool wear and surface roughness are experimentally studied to compare the effects of different cooling air temperatures. The results showed that minimum quantity lubrication (MQL) with cooling air significantly reduces cutting force, tool wear. Three different cooling air temperatures are used to investigate the effects of cooling air temperature on the machinability characteristics of 1Cr18Ni9Ti alloy. Based on the experimental results, MQL with cooling air of −50°C provides more favorable effects compared to the other two cooling air temperatures (−10°C, −30°C). However, different cooling air temperatures have a slight effect on cutting force under the same MQL condition.

Abstract: A new method for vibration control of aeronautical thin-walled workpiece in high-speed milling progress using a dynamic vibration absorber is presented. First, the theoretical model of the method is established and studied. Then the effectiveness of this method is testified via the simulation based on FEM. Finally, the feasibility of this method is discussed. The result shows that this method for vibration control of the aeronautic thin-walled workpiece in high-speed milling progress is effective and practical.

Abstract: Surface roughness plays an important role in product quality and has received serious attention for many years. It has formulated an important design feature in many situations such as parts subject to fatigue loads、precision fits、fastener holes and aesthetic requirements. In addition to tolerances, surface roughness imposes one of the most critical constraints for the selection of machines and cutting parameters in process planning. This paper focuses on developing a geometric model of turn-milling process in order to predict the surface roughness effectively so that we can offer reference or consulting in the practical machining process. The surface roughness model takes into account both cutting parameters and movement parameters such as cutter radius feed per tooth 、 cutting speed 、number of teeth 、cutters' eccentricity、 depth of cutting、spindle rotating speed and so on. Through this model, we discussed the influencing effects of various cutting parameters on the surface roughness and analyze which one has the most important impact.

Abstract: In order to estimate the static and dynamic characteristics of motorized high-speed spindle, the full parameterized FEM model of it is established and studied in the paper. After the FEM analysis of the spindle, the static stiffness, natural frequency and normal modes of vibration are obtained. Then, a design sensitivity analysis of some design parameters is conducted based on the finite element model to investigate their influence on the static stiffness and natural frequency of the spindle system. Through the sensitivity analysis, the optimal plan is proposed, the first natural frequency as the first objective function of optimization and the static stiffness as the second, which changes the objective function of multivariable into that of a single one. Therefore, it considerably increases the efficiency of optimization. The optimization leads to a noticeable improvement of static stiffness and first-mode natural frequency.