Machining method of closed three-elemental impeller with small flow

Abstract

The invention relates to a machining method of a closed three-elemental impeller with a small flow. The machining method comprises the following steps of: 1. mounting an impeller forging on a lathe machining center of a numerically-controlled machine tool, thereby carrying out semi-finishing treatment on the impeller forging; 2. machining a circular groove in an impeller cover and completing the machining of the whole flow channel of an impeller; and 3. welding a circular impeller cover shielding plate on the impeller cover and completing the contour finishing of the impeller cover and an impeller hub, wherein the semi-finishing treatment is performed by clamping the impeller forging on the lathe machining center of the numerically-controlled machine tool and carrying out the lathe machining on the impeller forging; the lathe machining in an axial feeding manner is performed until reaching an air inlet of an impeller blade; the outer contour of the impeller cover is formed by performing the lathe machining in a radial feeding manner; and the allowance of 4 to 6mm is left between the impeller cover and the impeller hub. The method has the characteristics of weldless flow channel forming surface, smooth flow channel, effective reduction in aerodynamic resistance, good aerodynamic performance and aerodynamic efficiency, good machining quality, high impeller strength, good corrosion resistance and the like.

Description

technical field [0001] The invention relates to a processing method of a small-flow closed-type ternary impeller, which belongs to the processing method of centrifugal compressor impellers. Background technique [0002] The small flow three-dimensional impeller is the work element of the centrifugal compressor. The characteristics of the impeller are: the inlet blade is twisted, the outlet width is narrow, the curvature of the hub disk surface and the cover disk surface are large, and the deviation of the flow path affects the aerodynamic performance of the impeller. Big. The impeller generally consists of three parts: the wheel cover, the hub and the blade. When the blade is milled on the wheel cover or the hub, it is called the two-piece impeller. Two or three impellers, the components of which are connected by electric welding, brazing, riveting or combination. For small flow ternary impellers, due to the narrow width of the blades, riveting and combination methods cann...

AI Technical Summary

Problems solved by technology

For small flow ternary impellers, due to the narrow width of the blades, riveting and combination methods cannot be used; while using electric welding, welding spatter will remain in the flow channel, which has a great impact on the aerodynamic characteristics of the flow channel, but due to the narrow width of the air outlet, it cannot be used. Grinding, and the welded impeller has low strength and poor corrosion resistance

For large-diameter closed impellers, due to the large width of the air inlet and outlet, the milling cutter head can directly enter the impeller flow channel for flow channel processing. However, for small-flow closed three-dimensional impellers, due to the above characteristics of the impeller, large Caliber closed impeller processing method for processing

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