where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -

LECOEUR ELECTRONIQUE
The Specialist of electronics for ultrasonic testing.

268 views
Technical Discussions
Kwok
Kwok
07:18 Aug-12-2004
Ultrasonic interference, acoustic noise

Are there any publication, to describe a method to eliminate or minimise an unwanted acoutic signal (i.e. Lamb) while maintaining an useful signal (i.e. shear or longitudinal)?


    
 
 
Balachander L
Balachander L
09:30 Aug-13-2004
Re: Ultrasonic interference, acoustic noise
----------- Start Original Message -----------
: Are there any publication, to describe a method to eliminate or minimise an unwanted acoutic signal (i.e. Lamb) while maintaining an useful signal (i.e. shear or longitudinal)?
------------ End Original Message ------------

What kind of structure are you interested in? In general, Lamb modes are generated only if the lateral dimension is comparable to the wavelength of the wave propagating. Is this a spot measurement or are you pulsing between sensors separated by a distance? If its the latter, and you want pure longitudinal or shear waves in such a structure, you need to control your phase velocity (and make sure you are sensitive to high Vp, meaning low Vg... possibly even contact transducers, although source influence effects will have to be looked at) by varying wedge angle etc. You basically get through-thickness resonances, which you can then easily detect by frequency content analysis. Further processing for appropriate signal analysis, of course, is by simple bandpass filtering, ensuring temporal selectivity of received modes. It depends on your test situation.


    
 
 

Product Spotlight

High-performance Linear Phased Array Probes

Available to order from stock in a range of 5MHz – 7.5MHz and from 16 to 64 elements. Designed w
...
ith piezo-composite elements, Phoenix phased array probes provide high-resolution imaging to maximise sensitivity; accurate ultrasonic detection and sizing of defects in welds; and effective corrosion mapping. Housed in a rugged stainless steel case for on-site industrial NDT applications.
>

Mentor UT – Ultrasonic Phased Array Flaw Detector

With Mentor UT, you get an accessible and efficient inspection experience. Create user-defined menus
...
and workflows (“apps”) with GE’s desktop software Mentor Create to ensure consistency, even for the most complex inspections, every time. Mentor UT is the first UT device to easily allow wireless connectivity and live streaming, so you get second opinions when you need them most—in real-time.
>

Ultrasonic Flaw Detector & Thickness Gauge: Smartor

SIUI’s newly launched Smartor is a combination of ultrasonic testing and ultrasonic thickness me
...
asurement. ●IP 66 ●Compact size: 198 (W)* 128 (H) *520 (D) mm ●0.9kg only with battery ●5.7" LCD with high resolution 640×480 pixels ●One-hand operation ●Multiple conventional UT functions ●Smart Test Wizard ●Weld Simulation
>

Lyft™: Pulsed Eddy Current Reinvented

PEC Reinvented—CUI Programs Redefined Corrosion under insulation (CUI) is possibly the greatest u
...
nresolved asset integrity problem in the industry. Current methods for measuring wall thickness with liftoff, without removing insulation, all have severe limitations. Eddyfi introduces Lyft — a reinvented, high-performance pulsed eddy current (PEC) solution. The patent- pending system features a state-of-the-art portable instrument, real- time C-scan imaging, fast data acquisition with grid-mapping and dynamic scanning modes, and flexibility with long cables. It can also scan through thick metal and insulation, as well as aluminum, stainless steel, and galvanized steel weather jackets. Who else but Eddyfi to reinvent an eddy current technique and redefine CUI programs. Got Lyft?
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window