US 6,629,463 B2 · Acoustic inspection of one-piece bladed wheels

Abstract

These objects are achieved by a method of acoustically inspecting a one-piece bladed wheel in which the wheel is driven in rotation; each blade of the wheel is subjected to mechanical excitation; its acoustic response is picked up and a corresponding electrical signal is generated; its frequency response is determined by computing a FFT; the electrical signal and the associated frequency response are stored; the characteristic frequencies of each blade of the wheel are identified; and a wheel is rejected or accepted depending on whether or not the frequency distribution obtained in this way matches a predetermined set of forbidden frequency distributions. Advantageously, an additional step is provided in which the defects of a blade are determined by comparing its frequency response with predetermined frequency responses that are characteristic of various types of defect.

Claims7

Dependent claims

A method of acoustically inspecting a one-piece bladed wheel, the method comprising the following steps:

a) driving the wheel in rotation;
b) subjecting a first blade to mechanical excitation;
c) picking up an acoustic response and generating a corresponding electrical signal;
d) performing an FFT computation to determine the frequency response of said first blade of the wheel;
e) storing the electrical signal and the associated frequency response;
f) repeating steps b) to e) for each blade of the wheel;
g) identifying characteristic frequencies of each blade of the wheel from the stored frequency responses;
and
h) rejecting or accepting a wheel depending on whether the resulting frequency distribution matches a predetermined set of forbidden frequency distributions.

6 more elements

Dependencies are inferred from the claim text.

Acoustic inspection of one-piece bladed wheels

Life of this patent

Acoustic inspection of one-piece bladed wheels

Life of this patent

Abstract

Claims7