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 -

I&T Nardoni Institute
A state-of-the-art company servicing the metal, mechanical, aeronautical and railway industrial sectors

593 views
Technical Discussions
Gowri santhosh Palika
NDT Inspector,
Royscan engineering pte ltd, Singapore, Joined May 2008, 51

Gowri santhosh Palika

NDT Inspector,
Royscan engineering pte ltd,
Singapore,
Joined May 2008
51
03:30 May-02-2008
DAC

Hi,
To make DAC curve, we have to consider half skip, full skip and one and half skip distances. what is the necessity to take one and half skip distance?


    
 
 
Michel Couture
NDT Inspector,
consultant, Canada, Joined Sep 2006, 822

Michel Couture

NDT Inspector,
consultant,
Canada,
Joined Sep 2006
822
08:08 May-02-2008
Re: DAC
----------- Start Original Message -----------
: Hi,
: To make DAC curve, we have to consider half skip, full skip and one and half skip distances. what is the necessity to take one and half skip distance?
------------ End Original Message ------------

One of the reasons you want your signal amplitude for 1 1/2 skip distance is that you have a better representation with 3 points than 2. You are covering a greater distance. I know many codes requires that you inspect only in the first skip, but personnaly, I do go to 1 1/2 skip because of the Near Field. I've seen times when I couldn't see properly my signal after my IP, but the indication was quite visible after the first skip. Your indication may actually blend itself with your IP.

Presently, at one of my client's shop, we do inspection using Longitudinal Wave and our calibration is set to 100% Backwall. But the code also says that if your Initial Pulse cover more than 1/3 of the metal path, your calibration should be of at least 6 Backwall Reflections for the reason I have expressed ealier.

You've probably have noticed that your IP is always somewhat wider than your Backwall or your indications.

Hoping this will be of help...
Michel


    
 
 

Product Spotlight

Trade-In Offer

We are offering our existing clients trade-in against Wavemaker® G3 systems, Standard (Blue) inflat
...
able rings and modules for excellent deals on the latest Wavemaker® G4mini system.
>

Ultrasonic Testing Immersion Tanks with Unmatched Scanning Features

TecScan’s non-destructive testing Ultrasonic Immersion Tanks & scanners are designed for high perf
...
ormance and demanding NDT testing applications. Our Scan3D™ line of High Precision Immersion Tanks are specifically designed for automated ultrasonic testing of complex composites parts used in aerospace and industrial applications.
>

AMIGO2

TSC Amigo2 - ACFM technology has developed a solid reputation for accurately detecting and sizing
...
surface-breaking cracks through paint and coatings. As the industry demands increased performance in speed, signal quality, and portability, it’s time for an evolution. It’s time for Amigo2.
>

Echomac® PA Rail Wheel Tester

MAC introduces two versions of Rail Wheel Testers using ECHOMAC® PA platform based on customer requ
...
irements.
>

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
s