The Design And Research On Turning-milling Combined Machine Tool For Large Seamless Rings

With the development of nuclear power, wind power, aerospace and other industries, as their key parts, large seamless rings’ demand is growing, their performance requirements are also getting higher and higher, therefore the production technology and equipment for large rings have been received more and more attention. At present, large seamless rings manufacturers use the conventional technology, which separates the turning, milling, drilling and grinding with different processing equipment for the production. It takes too much equipment investment, covers too large area and is hard to guarantee the accuracy and efficiency as a result of over-clamping. Although there are some common multifunctional combined machine tools on the market, the price is high for rings’manufacturers. Therefore, it is necessary to develop a turning-milling combined machine tools for large seamless rings with independent intellectual property rights and high price ratio.On the basis of the structural characteristics, technological characteristics and production characteristics of the large seamless rings, this project adopts integrated technology to develop a combined machine tool with turning, milling, drilling and other integrated functions. Clamping one time, the machine tool can finish most process. This accomplishes the high precision and high efficiency production demand of large seamless rings.According to the equipment users’ needs and large seamless rings’characteristics, the overall design goals and requirements are determined. Several types of machine tools’overall plan is designed based on that, and the best plan is determined in terms of the equipment performance, market competitiveness and feasibility. The modular design concept is applied to project planning. The main parts of machine tool are designed and3D modeled. The transmission system is detailed on the basis of calculation of cutting force in typical working condition, including feed transmission system in the horizontal and vertical direction, indexing feed transmission system, milling main transmission and worktable main transmission system.In order to guarantee the machining accuracy and improve the rigidity of machine tools, as the key components of machine tool, the crossbeam should be detailed designed and researched. Several structure plans of the crossbeam is designed by the traditional design method, including cast iron structure plan and welded structure plans. Their three-dimensional models are builded in SolidWorks and imported into ANSYS Workbench for static and dynamic performance analysis. Results showed the welded structure is better than the cast iron structure in terms of stiffness, natural frequency, weight, technology and other aspects. Therefore, the welded structure plan is adopted.