Materials Science Forum Vols. 626-627

Abstract: Drilling is one of the complex machining ways. The object of this investigation was to study cutting deformation in drilling by finite element method. A finite element model was developed to study the cutting deformation in drilling with various feed rates and various drilling velocities based on equivalent model. Experimental study on the cutting deformation in drilling was also carried out by a drilling quick-stop device. It is indicated that cutting deformation decreases when the drilling velocity and the feed rate increase; the closer the distance to the web is, the smaller the cutting deformation is; the laws of cutting deformation obtained from finite element method are according to that obtained from experiment.

Abstract: Along with the development and advance of science and technology, the quantity demanded of high technology and high performance mechanical equipment, such as screw pump, screw compressor, elastic and plastic extruder, steam turbine, blast engine and turbine, and so on, is great more and more in present society. And the requirement of performance is high more and more. The application of these products is widespread in many major industry fields of national economy, including military, petroleum, machinery, aviation, energy, chemical industry, elastic and plastic industry, etc.. The key part of these products is the rotor with special complex helical curved surface and leaf blade with particular slender curved surface. The machining level of them makes effect on the product performance and quality directly. In this paper, modern manufacturing technology, which makes use of tool nose’s NC trace of revolving disk milling cutter and whirlwind milling cutter to envelope milling slender curved surface by combined moving of several coordinate axes on special NC milling machine, was studied. The principle of the new technique was represented. The application instances are given in this paper.

Abstract: The main component of turbine is made up of stator and rotor, w hose function is to transform liquid energy in to mechanical energy on the main shaft. ANSYS CFX－BladeGen is applied to model turbine , ANSYS CFX－TurboGrid is applied to create a mesh for an turbine blade and then numerical simulation calculation on the obtained model is conducted. In the fact, the result of the above calculation indicates that ANSYS CFX BladeGen is more convenient and swift to fulfill the modeling request of turbine blade. When the performance of the turbine blade is achieved, these blades’ geometric data can be directly exported to Pro/ENGINEER or AutoCAD so as to further CAD and CAM.

Abstract: An axisymmetric two-dimensional thermal model, whose boundary conditions are constantly changing both in magnitude and position, has been developed based on the basic principles of electrical discharge machining (EMD) using the finite element method (FEM). The thermal load of heat flux are applied on the surface of the workpiece using the programming language Python provided by ABAQUS FEM software. The temperature field distribution, diameter, and depth of the crater are simulated by this model. Finally, the model is validated by comparing the theoretical crater diameter with the experimental crater diameter obtained from the experimental setup developed in the laboratory.

Abstract: Rule-based reasoning (RBR) and weight decision making have been widely used in a lot of decision support systems. According to the waste phenomenon of manufacturing corporations due to the reasonless use of tools during production process, and considering the characteristics of former tool selection systems, develop a tool optimal selection system with Visual Basic 6.0 as development tool and SQL Server 2000 as database developing platform. The system adopts the rule-based reasoning and weight decision-making theory, combines fuzzy theory, artificial intelligent technology and production conditions of corporations. According to the information of workpiece and processing conditions imported by users, the system can select the reasonable tools for users. The system overcomes the limitation of single theory tool selection system, simplifies reasoning mechanism and structure of knowledge base, makes programmer easy to realize, promotes operation efficiency of system, and raises the accuracy and efficiency of tool selection in actual production. A developed prototype system and an example have verified some presented techniques and the research results are the basis of the future development.

Abstract: A new one-side finish machining method for the profile of globoidal indexing cam in high speed, which modifies the tool path of traditional enveloping method, was put forward. The new method is useful for overcoming the defects caused by traditional enveloping method, can realize one-side machining of globoidal indexing cam, can improve the machined surface quality and the meshing characteristics of the cam mechanism. The practical calculation formulas of tool path modification is given, which can be used in developing the CAD/CAM software of the globoidal indexing cam. The new method has great practical value.

Abstract: This article introduces a new way combining electrochemical and traditional abrasive grinding belt called Electrochemical Abrasive Belt Grinding. Through the study of grinding the 0Cr17Ni4Cu4Nb stainless steel, analyzes the influence of all the key factors for surface roughness during the process of electrochemical abrasive belt grinding by means of multivariate orthogonal experimental methods and single factor experimental method.

Abstract: In order to reliably keep and fasten the aligned posture of large components such as fuselage in aircraft digital assembly, a new adaptive posture following and keeping method based on the application of aerostatic bearing and universal ball joint was proposed, and a flexible posture following and keeping fixture was developed. Fundamental experiments of the fixture were conducted, and the results show that the approach can meet the requirement of posture following and keeping. In applications, the fixture can be set multiple-point on the surface of the large component, such as periphery and lower abdomen.

Abstract: Based on the milling force testing experiments on machining the carbon structural 45 steel, the study on the distributing principle of force density function for complex three-dimension groove milling insert with the waved-edge milling insert (the curve rake plane) developed by Harbin University of Science and Technology is studied. On the basis of the milling force mathematical model, the force density function of the curve rake plane is built by the milling force experiments and tool-chip contact area experiments. Having quantitative calculation on the force density function and programming, the distributing model of force density function is shown with 3D figure, so to analyze its distributing principle. All these studies will provide a theoretic base for the stress field analysis and solving the cutter disrepair which is the key problem in the automatization production and groove optimization.

Abstract: Aiming at the existed deficiency of integrated application of digital technologies, the integration scheme of digital design/manufacturing/management in aeroplane process equipments is proposed. Its collective technologies and practical research items are analyzed, together with existed CAX systems and their data transfer relationship with MES/PDM. The united information model and knowledge reuse technologies are studied to ensure the successful product development. Based on the above researches, an integrated application system is set up, which is composed of seven sub-systems, like management of process equipments orders etc. Therefore, “paperless” manufacturing in the Hafei Aviation Company has finally come true.