Numerical Control Machining Method of Titanium Alloy Integral Impeller and Its Supporting Fixtures

Abstract

The invention relates to the technical field of mechanical machining, and relates to an efficient numerical control machining method for an integral titanium alloy impeller and a matched tool clamp. The machining method includes the steps that S1, an impeller workblank is clamped and positioned to a common tri-axial numerical control machine tool through the clamp; S2, excess materials of the impeller workblank are removed as much as possible on the common tri-axial numerical control machine tool; S3, the impeller workblank from which the excess materials are removed is moved to a five-axis numerical control machine tool, the impeller workblank is machined roughly, blades of the impeller are machined finely, corner-clearing machining is carried out on the roots of the blades, and a hub of the impeller is machined finely; S4, the impeller machined in the step S3 is measured in a three-coordinate mode; S5, the impeller measured to be qualified is disassembled from the special clamp, and the whole machining step is completed. The machining time of the integral titanium alloy impeller can be effectively shortened, the manufacturing expenses are reduced, and the machining quality is improved; as the special tool clamp is used, the problem of machining integral impellers in batches is well solved, the labor efficiency is improved, the quality of impeller machining is effectively promoted, and the manufacturing safety performance is improved.

Description

technical field [0001] The invention relates to the technical field of mechanical processing, in particular to a numerical control processing method of a titanium alloy integral impeller and a supporting fixture thereof. Background technique [0002] As the power core of the aircraft, the aero-engine is the most important part of a large number of aviation parts. The main materials of the parts are titanium alloys and high-temperature alloys. Titanium alloy parts are mostly used in the cold end parts of aero-engines (fans and compressors, etc.), while superalloy parts are mainly used in the hot end parts (turbines, etc.). [0003] The integral impeller is a key component of aviation, aerospace, and marine engines. With the improvement of engine performance requirements, the shape of the integral impeller becomes more complex. Its characteristics are: thin blades, large twists, long blades, and small blade intervals. From the analysis of impeller materials, titanium alloy is...

AI Technical Summary

Problems solved by technology

[0005] (1) The hub of the impeller is narrow, the blades are relatively long and thin, and the rigidity is low. Vibration and deformation are prone to occur during processing, which makes the overall processing more difficult.

[0006] (2) The curved surface of the impeller is a free curved surface, and the blades are seriously twisted, which is very easy to interfere during processing, and the processing is difficult

[0007] (3) In the case of a long tool extension, the tool rigidity is poor, it is easy to bounce the tool, and it is difficult to control the cutting depth while ensuring the processing efficiency

[0008] (4) The chemical, physical and mechanical properties of titanium alloy materials make them particularly difficult to process

[0010] Using this conventional method, since the impeller removal exceeds 90%, the rough machining takes up a rather long machining time of the five-axis machine tool, about 60% of the entire machining time, so the machining efficiency is low and the machining cost is high

In addition, there is no special tooling and fixture for traditional processing, so every time a whole impeller is processed, it needs to be repositioned and aligned. The auxiliary processing time is more expensive, and the processing efficiency is low, which is not conducive to mass production.

Moreover, this positioning method has fewer degrees of freedom (usually 3 degrees of freedom). When processing large-sized integral impellers or impellers of difficult-to-machine materials, the workpiece is prone to move due to the large cutting force, resulting in The scrapping of the entire impeller is time-consuming, labor-intensive and material-consuming, so there are serious potential hidden dangers

Images