Study On Blade Manufacture Oriented CNC Abrasive Belt Grinding System

In recent years, as core components in turbo-machines which have been widely used in aerospace and electric power generating industries, parametric or sculptured surfaces are regard as a difficult part in manufacture and have been drawing more and more attention. Along with the rapid development in the technology of CAD/CAM/CNC, domestic manufacturers have made great progress in the milling machining of blade both in precision and efficiency. On the contrary, a sharp contrast is that the grinding machining of the blade still relay on manual operation. The delay in the automation of the blade free form grinding has been the bottleneck of the high quality blade manufacture because of the increase in dimensions of the blade size and the huge demand in quantity. As a result, in order to break the unbalance between the cutting and grinding machining of the blade sculptured surface, it is significant to develop a blade grinding oriented system which has advantage in economy, high efficiency and owns independent intellectual property in practical way.In this paper, in order to control the removal rate during the grinding process, position and orientation control strategy for contact wheel of six-axis blade CNC (Computer Numerical Control) abrasive belt grinding system have been studied, and we presented the definition of position and orientation control strategy called Normal Contact, which has some advantage including that, making full use of the structure rigidity of the machine configure, decreasing the difficulties in inverse kinematics solution of each joint variable based on the homogeneous transform equation, and making the controlling of the pressure between contact wheel and work piece more convenient. To achieve high efficient and gauging-free tool-path generation, drum contact wheel has been involved in. By means of adjusting the angle between the rotate axis of contact wheel and the direction of feed, we can avoid the gouge.Under the assistance of CAD software and CAD models of blade, which have been the pool of all information needed during the manufacture and quality examination, By using of some API functions supplied by the UG/Open API module, we can get the information such as the coordinates of point and normal vector of any point locating on the free-form surface of the blade, and also including some geometrical characteristics on the surface, which are significant for the tool-path planning and generation. In addition, the regions distributing on the surface for machining can be gutted at the same time.According to the configure data of the machine tool, we could construct a virtual machine in the UG environment. Relaying on the kinematics simulation module of UG, the machining process can be simulated. The simulation can enable us to eliminate the mistakes of the CLP (Cutter Location Position) file by an interactive way.