Machining method for improving dimensional precision of connectors of hypersonic velocity wind tunnel nozzle

Abstract

The invention discloses a machining method for improving the dimensional precision of connectors of a hypersonic velocity wind tunnel nozzle. The machining method includes the steps of machining preparation, coarse machining, reference surface finish machining, nozzle profile finish machining and cutting-off of straight sections. According to the machining method, the hypersonic velocity wind tunnel nozzle is machined section by section, the straight sections for improving the measuring precision are added to the sharp corner positions at the positions of the connectors of the sections, as thestraight sections are measured and machined at high precision, the dimensional precision of the sharp corners of the positions of the connectors is guaranteed, and finally the straight sections are removed. The machining method is suitable for controlling the dimensional precision of connectors when pipelines with curved lines, pipelines with inclined lines and workpieces with curved cavities andthe sizes of connectors not easily measured are used for assembling and splicing, can meet the high-precision requirements during section-by-section butt joint of the hypersonic velocity wind tunnelnozzle, and has the beneficial effects of being economical, practical, easy and convenient, and the difficulty of machining control is greatly lowered.

Description

technical field [0001] The invention belongs to the field of hypersonic wind tunnel test equipment, and in particular relates to a processing method for improving the dimensional accuracy of a nozzle interface of a hypersonic wind tunnel. Background technique [0002] The wind tunnel is an indispensable ground equipment in the development of aircraft, and the nozzle is the key component in the wind tunnel. The nozzle of the hypersonic wind tunnel is a Laval nozzle. The molded line is in the shape of an asymmetrical hourglass with contraction in the middle and expansion at both ends. The difference between the minimum size in the middle and the maximum size at both ends can reach more than 10 times. [0003] Due to the limitation of the shape of the hypersonic wind tunnel nozzle itself, the machining industry adopts the method of segmental processing and then assembly. This method has very strict requirements on the quality control of the interface between the two sections. ...

AI Technical Summary

Problems solved by technology

[0004] When the nozzle is processed in sections, the shape curvature near the interface of the smallest section in the middle is large and the size is too small, so measuring tools cannot be used to measure the interface size during the processing

At present, the accuracy control of the interface in the industry is mostly to measure the size of the external reference, relying on the accuracy of the processing equipment itself to indirectly guarantee the dimensional accuracy of the interface, the accuracy can only be guaranteed at ±0.05mm

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