Papers by Keyword: Flank Milling

Abstract: The ruled surface of impeller is widely used in the industry of automobile, shipbuilding, aerospace and aeronautics. Researches on the manufacture of blade possess general meaning. The importance of their performance in the certain field and the non-replace ability of their functions in the specified mechanical systems have resulted in that the technology of manufacturing and measurement for ruled surfaces has been a critical research project in the field of dimensional manufacturing and measurements. With the rapid development of the modern science and technology, complex ruled surfaces are employed more and more widely, but their tolerances become narrower and narrower. The common impeller surfaces represented by NURBS are given and then curve and surface interpolation algorithm represented by NURBS are presented. These provide theoretical foundation for NC machining programming of impeller surface. Principals of normal offset curve and inclined offset surface are used to simplify the model. The NC milling method of divide area is presented to raise machining efficiency and to improve quality of machined surface. The machining efficiency is important in line property of rule surface, flank milling rule surface with end-milling, improve surface quality and cutter efficiency. This paper presents a calculate method to generate five-axis flank milling NC code of divide area in the blade of compressor with Vericut simulating the five-axis flank milling NC code and measurement the result of processing that verification the precision of five-axis flank milling. This paper also simulates four-axis machining for comparing cutting efficiency between five-axis machining and four-axis machining and the status of both the great differences in processing efficiency.

Abstract: To improve the efficiency and precision of five-axis numerical control machining for undevelopable ruled surfaces,a cutter-location optimization algorithm was proposed for flank milling of blades with a toroidal-end cutter. Firstly, it is established initial cutter-location of toroidal-end cutter by optimizing algorithm of three-point offset based on geometry features of toroidal-end cutter, and optimized cutter vector by introducing scaling factors. A new method which was based on dynamic sliding index calculating optimal cutter orientation vector was proposed. The method which applied deviation measurement algorithm computed overcut or undercut values of programming error in different scaling factors state. Finally, through the instance of machining verified the rationality of the method, and effectively reduces programming error.

Abstract: The impeller is an important typical part of machinery and equipment industry, and is widely used in energy and power, aerospace, petrochemical, metallurgy and other fields. However, due to the complex shape of the impeller blades, forming more difficult. Flank milling have many advantages, such as forming good accuracy, high efficiency. Therefore, in the paper will choose flank milling for impeller milling. Based on the properties of titanium alloy material and the external characteristics of the impeller blades, proposed control method for machining distortion of impeller blades. Using three offset method to calculate the initial tool position of cylindrical cutter flank milling undevelopable ruled surface, then calculate the initial tool position of cone ball cutter to plan tool path of milling. Through the VERICUT software to simulate the whole process of the impeller flank milling, in order to verify the tool path planning and determine the interference between the tool and the workpiece, the tool and the workpiece does not occur. Finally, through experiments to verify the feasibility of planning algorithm. The trajectory planning and simulation of flank milling titanium impeller blades are foundation of improvement the processing efficiency of the impeller blades and better surface quality.

Abstract: In this paper, titanium as the research object, which is usually used as the aerospace engine blisk manufacturing materials, as a typical difficult-to-machine materials, on the basis of its machinability is analysis, research process bisk processing of the main types of flank milling, flank milling fundamental experiments of titanium was carried out, the cutting force of the processing is collected and analyzed in order to optimize the process parameters; Studying ball end mill for the stress analysis and modal analysis in order to obtain the stress, strain and distribution of vibrations in the flank milling titanium, which can provide a reference for future flank milling process parameters titanium blisk, and provide theoretical basis for efficient, stable and safe cutting and optimization tool design.

Abstract: For the low efficiency and poor surface quality problem of finishing ruled surface blade in the traditional method, tapered ball end mill cutter location optimization methods had been proposed to ensure that the envelope surface of tapered ball end mill is close to intractable ruled surface blade as much as possible. First, the tapered ball end mill initial cutter location was obtained based on the improved two point offset algorithm. Then to realize the cutter location optimization calculation, selected three point in tool axis to slide for the target of the minimum range between cutter envelope surface and blade surface. Finally, the blades instance was calculated according to the obtained tool center point and optimized tool axis vector. Simulation and experiments verified the effectiveness of cutter location optimization method proposed in this paper.

Abstract: Machined surface texture is a very critical factor since it directly affects the surface quality and part mechanical behavior. In modern manufacturing system, it is necessary to develop systematic models, which can represent a realistic picture how the machined surface is produced during milling process. In this paper, a general geometric kinematic model is presented to build kinematic relationship between the arbitrary point of the cutter flute and the arbitrary point of the machining surface. And then, a nonlinear programming problem is constructed to calculate a scallop height along a normal direction of an arbitrary point on nominal part surface, three dimension profiles can also be simulated, a case is utilized to validate the feasibility of the proposed model.

Abstract: In this paper, the factors affecting the surface roughness by flank milling are selected, and the blade machining experiments are implemented according to the orthogonal table designed, Then, the blade surface roughness are measured using TR200 instrument, and the surface roughness of the blade results are analyzed using visual analysis method and variance analysis method. Finally, the impact of various factors on the blade roughness is obtained, and the optimal process parameters of flank milling aluminum alloy blade are given.

Abstract: Five-axis flank milling is an important machining technique, especially in machining of complex parts. Tool posture vector can change easily using two axes of rotation to achieve optimum cutting conditions. However, the tool posture vector may change beyond the interpolation plane. This will result in overcut or undercut. In this paper, an adaptive interpolation algorithm of tool posture vector is proposed. In the proposed algorithm, the commanded feedrate for linear axis is kept constant for most time and adaptively adjusted to confine the chord error within a specified tolerance range during the interpolation process. The tool posture vector changes in the interpolation plane with a constant rotation degree. Simulation results from example are provided to verify the feasibility and advantages of the proposed scheme.

Abstract: In the context of 5-axis flank milling, the machining of non-developable ruled surfaces may lead to complex tool paths to minimize undercut and overcut. The curvature characteristics of these tool paths generate slowdowns affecting the machining time and the quality of the machined surface. The tool path has to be as smooth as possible while respecting the maximum allowed tolerance. In this paper, an iterative approach is proposed to smooth an initial tool path. An indicator of the maximum feedrate is computed using the kinematical constraints of the considered machine tool, especially the maximum velocity, acceleration and jerk. Then, joint coordinates of the tool path are locally smoothed in order to raise the effective feedrate in the area of interest. Machining simulation based on a N-buffer algorithm is used to control undercut and overcut. This method has been tested in flank milling of an impeller and can be applied in 3 to 5-axis machining.

Abstract: In order to improve quality and efficiency of the overall five-axis milling for arbitrary surface impellers. In rough milling, the arbitrary surface was replaced by fitted ruled surface, the flank milling was a good method to replace the point milling. In semi-finish milling, the primal surface was replaced by piecewise ruled surfaces, using step flank milling to gain the satisfaction in model’s nicety and machining efficiency. Then , algorithm of the paper is proved to be viable by Model building, NC programming and machining.