Loading patent…
AssigneeLockheed Martin Corporation
InventorsMarc Dubois, Peter William Lorraine
Estimating the term…
An invention to measure of objects of non-homogeneous ultrasonic impedance in the testing path is provided to detect the present of flaws in any part of the object. The invention utilized a reference signal to compare against the actual signal derived from ultrasonic testing of the object. Reference signals are determined based upon the known or calculated properties of the object's layers or previously obtained signals measured from the object.
A flaw detection system comprising of:
A method to detect flaws comprising the steps of:
The method of claim of step 20 wherein the object is a multi-layered object.
An apparatus for performing ultrasonic testing of an object, the apparatus comprising:
A flaw detection system comprising of:
A flaw detection system comprising of:
A flaw detection system comprising of:
A method to detect flaws comprising the steps of:
A method to detect flaws comprising the steps of:
A flaw detection system comprising of:
Dependencies are inferred from the claim text.
Drawings are temporarily unavailable. Open the PDF at USPTO
From the US filing history. Foreign family members aren’t listed.
By comparison: with stored values, e.g. threshold values
Display arrangements, e.g. colour displays: display representation or displayed parameters, e.g. A-, B- or C-Scan
Details , e.g. general constructional or apparatus details: arrangements for calibrating or comparing, e.g. with standard objects
Generating the ultrasonic, sonic or infrasonic waves , e.g. electronic circuits specially adapted therefor: with time characteristics
Term ended 16 Aug 2021 (estimated)
1. Technical Field
This invention relates generally to material testing and more particularly to nondestructive detection of flaws in objects. A flaw may be a crack in an object, a void in an object and/or a deviation from dimensional specifications of the object, and any other parameter that causes a change in mechanical resonance.
2. Description of the Related Art
For a more complete understanding of the present invention and the advantages thereof, reference should be made to the following Detailed Description taken in connection with the accompanying drawings in which:
FIG. 1 shows an example of an ultrasonic signal (A-scan) used to detect a defect within a single layered object;
FIG. 2 shows a typical experimental ultrasonic signal (A-scan) obtained from a 3-layered object wherein the object is without defect;
The invention comprises of a system and process for interpreting complex ultrasonic echo signals from objects whose impedance varies across the ultrasonic transmission/echo path.
In the present invention a reference signal is used to compare against an ultrasonic test's actual signal to determine if a defect exists. The reference signal can be created by using a synthetic computed reference signal, a signal from a database containing synthetic signals or experimental signals from reference parts, or a signal averaged from the tested part. If a synthetic computer reference signal or a database reference signal is used, the signal must be corrected for the ultrasonic phase and amplitude response versus frequency of the experimental system currently used (like response of the detector and electronics). The advantage of using an averaged signal from the currently inspected part is that such corrections are not necessary.
FIG. 3A shows a block diagram of the methodology utilized to obtain a reference signal from a database. In step 302A, the object's parameters are determined. Once the parameters are know, then, in step 304A, a reference signal database is accessed to chose the signal that best fits the object's parameters. Once a reference signal with the correct parameters are chosen in step 308A, the reference signal is corrected for detector and electronic response of the ultrasonic inspection system in step 310A. Thereupon, the reference signal is normalized in step 312A.