Based on economical and practical thoughts,a special machining method of the blade surfaces is presented in the paper,and some relative contents about it are simply introduced,such as its NC machining process method,the structure of the machine tool,work pieces' installation and the fixture,machining process and establishment and process of the blade surfaces' mathematical model.

This paper summarizes the present inspecting methods and the developing trend of blade surfaces inspection,and introduces a better device-the Laser-scanning Machine System.

The blades are key parts to the turbine、the aeronautic engine、the ship’s thruster and others equipments,its quality will directly influence the steamy turbine’s working,but the blade surfaces’quality will directly influence the blades’quality .

The paper introduces the construction features of undevelopable ruled surface integral impeller and two 5-Axis numerical control mill machining methods of vane shape which are "line contact" (flank milling) and "point contact".

The new blade surface quality evaluating indexes are put forward through the analysis of present situation of measurement on the surface tolerance of blade.

Calculations of flow field of flow surface of impeller S1 and S2 were carried out;Effect of impeller of different blade profile on the highest pressure point,optimum operating point,shape of pressure curve and efficiency of the fan were analyzed.

In this paper, a simple two-dimensional inverse method is presented which can be used to designthe forward-swept or the backward-swept blade shape on the stream surface of revolution of the im-peller in centrifugal fans.