Electric discharge machining process for ternary rectification body shrouded impeller

Abstract

The invention discloses an electric discharge machining process for a ternary rectification body shrouded impeller, and relates to the technical field of electric discharge machining. The machining process comprises the following steps of installing a workpiece, aligning hole sites, machining a conical hole, machining a cylindrical hole and completing machining. According to the machining process, a tool electrode assembly is arranged on a lifting mechanism, the output end of a driving motor drives a second electrode to slide to the lowermost end on a first electrode through a driving wheel, a rack and a rotating ring, electric corrosion products generated in the machining process are brought out, and after the output end of the driving motor rotates reversely, the electric corrosion products in a deep cylindrical hole can be effectively discharged, so that the arc discharge or short circuit phenomenon is avoided, and the hole wall quality in an air film hole is ensured; and by arranging a mechanical arm and the lifting mechanism, the oblique interference part of the workpiece can be avoided, and it is guaranteed that the air film hole is smoothly machined in the to-be-machined position of the joint between a blade body and a blade crown of the workpiece.

Description

technical field [0001] The invention relates to the technical field of electrical discharge machining, in particular to an electrical discharge machining process of a ternary rectifier with crowned impeller. Background technique [0002] The working conditions of the internal turbine blades of the aero-engine are very harsh, and they rotate at high speed under the impact of high-pressure corrosive gas. The structure mainly relies on the cooling film holes opened on the end surface for cooling. The existing technology usually uses EDM technology to process the blades. The microporous machining of cooling gas film holes means immersing and positioning the workpiece in the EDM working fluid, using the rotating integrated electrode to directly process the tapered holes and cylindrical holes on the processing surface, and at the same time, through the integrated ultrasonic vibration assisted Equipment to discharge the electro-corrosion products generated during the EDM process. ...

AI Technical Summary

Problems solved by technology

[0003] However, during the long-term modeling and processing of ternary rectifier crowned impeller blades, our company found that the existing technology still has certain disadvantages: 1. The structure of the gas film hole is small and deep, and the gas film hole on the end face is completely opened Previously, ultrasonic vibration could only cooperate with the working fluid to bring out the electro-corrosion products on the side of the one-piece electrode near the orifice, but the electro-corrosion products located at the lower part of the one-piece electrode with a relatively large height and diameter in the hole could not be effectively removed, resulting in arcing Or short-circuit phenomenon, which affects the quality of the hole wall in the lower part of the gas film hole; 2. Since the blade crown of the three-dimensional rectifier shrouded impeller is relatively longer than the blade body of the blade, and the junction of the two has a certain structural angle , resulting in interference phenomenon when the integrated electrode is processed at this place, and there is air flow interaction between the processed interference air film hole and the rest of the cooling air film hole, resulting in the cooling effect of the blade to be improved

Images