Research on Technology of Root Clearance of Blades by CNC 4-Axis Machine Tools (I)
In order to make the machine part’s surface smooth and wear resistance, it is necessary to make the blades clean. Generally, the machine tool is used to grind the root of the blade. However, this is a strong interference between the bank and the tool. In order to reduce the interference, CNC 4-axis machine tools are often used for root clearance in recent years.
In this study, the use of CNC 4-axis machine tools for the root clearance was investigated. It is known that the tool had a significant effect on the root clearance and the cutting effect. Therefore, the influence of the cutting edge geometry of the tool on the root clearance of the blade was investigated in detail. In this study, a model of the blade and its root clearance was established using Reverse Engineering software. The cutting edge geometry of the tool was measured using the Two-dimensional contour error measuring instrument. The cutting force model and the tool-blade interference model were built based on the measured data. The cutting force model was used to calculate the cutting forces in the root clearance machining process and the interference model was used to evaluate the interference between the tool and the blade.
The results of the experiments showed that the shape of the cutting edges of the tool had a great influence on the cutting forces and the interference. The cutting edge geometry affects both the cutting forces and the interference. When the cutting angle is large, the cutting forces increase and the interference is large. In contrast, small cutting angles lead to lower cutting forces and the interference is reduced. The research results provide useful guidance for the design and selection of the cutting tools used in the root clearance machining.
In order to further reduce the interference generated during the process, the machining parameters should be optimized. In this study, the cutting parameters, including the cutting speed, feed and depth of cut, were optimized using an optimization algorithm. The optimization algorithm was used to minimize the interference between the tool and the blade. The results of the numerical simulation showed that the optimized machining parameters have little influence on the root clearance. However, the cutting force and the interference were significantly reduced.
In conclusion, the use of CNC 4-axis machine tools for root clearance is effective to reduce the interference generated during the machining process. Moreover, the cutting edge geometry of the tool and the cutting parameters have a great influence on the cutting force and the interference. By optimizing the cutting parameters, the cutting force and the interference can be significantly reduced. The research results provide useful guidelines for the design and selection of cutting tools for root clearance machining.
