Machining method for guaranteeing shape completeness of air inlet and air outlet side circular arcs of blade

[0020] Such as Figure 1~4 As shown, a processing method to ensure the integrity of the arc shape of the inlet and exhaust edges of the blade. The blade profile is processed by longitudinal CNC milling, and the blade profile is divided into the inlet side arc area and the exhaust side arc. Area 2, blade basin surface area 3 and blade back surface area 4 are four processing areas. The air inlet arc area 1 includes air inlet arc 13 and the tangent point 8 of air inlet arc and vane curve The section 7 extending 3mm outside the arc of the intake side and the tangent point 5 of the arc of the intake side and the blade back profile curve extending the section 6 of 3mm outside the arc of the intake side, the section 2 of the exhaust side arc including the exhaust Edge arc 14, the tangent point of the exhaust edge arc and the blade cone profile curve 9 An interval extending 3mm from the exhaust edge arc 10 and the tangent point of the exhaust edge arc and the blade back profile curve 11 to the exhaust edge The arc extends 3mm in the interval 12, the blade basin surface between the inlet side arc area 1 and the exhaust side arc area 2 is the blade basin surface area 3, the inlet side arc area 1 and the exhaust side arc area The blade back profile between the arc areas 2 is the blade back profile area 4. Among them, the two processing areas of the leaf basin surface area 3 and the leaf back surface area 4 are processed by the normal tool path method controlled by the CNC program. The tool path step distance is 0.3mm, which makes the roughness value relatively large to ensure The overall machining efficiency of blade profile CNC milling is not greatly affected; the two machining areas of the air inlet side arc area 1 and the exhaust side arc area 2 are processed by the method of encrypted tool path through the control of the CNC program, and the tool path step is It is 0.04mm, making its roughness value close to the technical requirements.

[0021] The processed blade profile is polished. First, semi-finish polishing is performed on the processed leaf pot profile area 3 and leaf back profile area 4, using an abrasive belt with a particle size of 400# and 80% of the planting sand area. , Using 40m/s grinding speed for processing, the polishing removal depth is 0.02mm; then the entire blade profile is finely polished, using an abrasive belt with a particle size of 600# and 40% of the planting sand area, and 30m/s grinding The cutting speed is processed so that the roughness value of the overall surface of the blade meets the technical requirements, and the polishing removal depth is 0.005mm.