The Separation Of Micro Surface Profile Characterization Of Integral Impeller And Its Applications

Integral impeller is a key component of turbo machinery, and the integral impeller is widely used in aviation, aerospace, chemical, energy and other industrial fields. There are a lot of curved surfaces of the integral impeller. The traditional processing methods can’t satisfy the processing requirements, and so the current processing method of integral impeller is based on precision milling by five axis machine tools. The integral impeller blade is the key factor of influencing the integral impeller performance, and the surface quality of the blade, especially the surface microscopic contour feature, has a direct impact on the efficiency of the impeller inlet, the work efficiency and dynamic performance.In order to have a detailed study of the contour structure characteristics five-axis machine tools milling machining of integral impeller surface, by using surface profiler to measure the key parts of the blade in the microscopic view the microscopic contour data of the integral impeller blade can be obtained in this paper. And by using the data obtained, the 3D micro model of the milling blade surface can be established. A series of experimental analyses are developed, as well as the characteristic signal power spectrum, and so the blade profile signal frequency components can be obtained. The power spectrum of the area S is then explained which is used as the evaluation of one of the characteristics of the leaf surface quality. By using the method of wavelet analysis, the wavelet decomposition and reconstruction of the obtained data is performed. Through the separation of the components of the data signal, the distribution of the integral impeller blade surface roughness characteristics can be obtained which can be used as the second characteristics of blade surface quality evaluation.In order to ascertain the influence of nose radius and cutting line spacing of the two parameters on the surface quality of integral impeller blade in machining process, this paper designed seven groups of experiments through the method of control variable. Use the nose radius or cutting spaced one of the parameters as variables, and control the other parameters constant, so as to study the influence of the changes in the parameters on the two characteristics of the blade surface. By the repeated test in five-axis machine tools milling and continuous measurement of the change of the blade surface quality, the blade surface micro contour feature data in the process of machining can be obtained. Through the analysis of the data model and power spectral, these two parameters, nose radius and cutting spaced, are drawn to the influence law of integral impeller blade surface quality and selection priority level in the practical machining, which is actually applied in the impeller quality test. In this paper, the surface quality can be evaluated, accurately and objectively, by the calculation of the parameters of the micro profile on the impeller surface.