Blade for engine containment test and machining method of notch of blade

Abstract

The invention belongs to the technical field of aeroengine test design, and particularly relates to a blade for an engine containment test and a machining method of a notch of the blade. The notch stretching from two opposite side faces to the middle is formed in the position, on a tenon, of the blade for the engine containment test, a through section of the notch is formed, round through holes are further formed in the bottom of the notch of the blade, and the bottom of the notch is formed. The machining method of the notch includes the steps that firstly, the through holes are preformed in the two positions with the interval L of the tenon of the blade, and the bottom of the notch is formed; and then cutting-through is carried out from the opposite ends of the through holes towards the outer end face of the tenon of the blade, and the through section of the notch is formed. By means of the method, the problems that in an existing groove-shaped line cutting scheme, when the length ofa remaining section is too small, the anti-bending capacity of a groove-shaped structure is reduced, and the groove-shaped structure is not easy to machine are solved; and by machining the round holestructure, stress concentration of the fly-off section of the blade can be greatly reduced, and the control precision of the fly-off rotating speed is improved.

Description

technical field [0001] The application belongs to the technical field of aero-engine test design, and in particular relates to a blade used for an engine containment test and a notch processing method thereof. Background technique [0002] All military and civil aircraft engine specifications worldwide have inclusive requirements without exception, and the content is basically the same. In a nutshell, a single blade should be contained after the cross-section outside the tenon breaks. Before the complete machine containment test required for engine certification, sufficient verification of the containment capacity of the casing is required. The containment test under the tester condition is an effective and necessary means to verify the containment of the casing. attached figure 1 It is a schematic diagram of the containment test device under the condition of the tester. attached figure 1 1 is the casing fixing plate assembly, 2 is the drive shaft assembly, 3 is the upper...

AI Technical Summary

Problems solved by technology

[0006] The notch structure of linear wire cutting has a very large stress concentration due to the small curvature radius of the notch root. Generally, the stress concentration factor is above 10, and the processing surface state of wire cutting is difficult to determine. These two reasons make it impossible to accurately calculate the remaining section. Stress state, the breaking force of the blade will not be controlled by the average stress of the flying breaking section, so the prediction error of the flying breaking speed of the blade is large

Due to structural constraints, the groove width of groove-shaped wire cutting cannot be too large, so there is still a certain stress concentration in the structure. In addition, when the length of the remaining section is too small, the bending resistance of the groove-shaped structure will decrease, and it will be difficult to predict due to the center of mass offset. The estimated bending moment changes, both of which will reduce the prediction accuracy of the fly-off speed

[0007] 2. Cost

[0010] The speed error of the flying break of the existing notch structure is relatively large, and repeated tests are required, which affects the efficiency

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