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 -

1292 views
Technical Discussions
creed
NDT Inspector,
Vietnam, Joined Jul 2009, 37

creed

NDT Inspector,
Vietnam,
Joined Jul 2009
37
04:48 Dec-06-2012
Eddy current testing for welds

Hi everyone,
I have quick questions related to Weld Eddy Current Tesing:
1. " When we use 100kHz probe, Can we detect subsurface defects within 2mm depth? because we used the calibration block with 2mm depth slot signal is reference level (eg. 80% of full screen)?
2. With the thin thickness of parent metal in weld testing will affect to the ECT signal? and How to control if YES?
Eg: the weld with the parent metal thickness is 2 or 3mm whilst we us ED slot calibration block with 5mm thick.
Thanks

 
 Reply 
 
John Hansen
Director, - Eddy Current Technology
ETher NDE Ltd, United Kingdom, Joined Oct 1999, 74

John Hansen

Director, - Eddy Current Technology
ETher NDE Ltd,
United Kingdom,
Joined Oct 1999
74
10:32 Dec-06-2012
Re: Eddy current testing for welds
In Reply to creed at 04:48 Dec-06-2012 (Opening).

1) At 100 kHz in Carbon Steel (Ferromagnetic) the Standard Depth of Penetration (aka skin depth) is about 0.03 mm. This means that as standard then eddy current can only be considered a surface method.

2) I think your question is now answered unless your material is non-magnetic.

All the best

John Hansen

1
 
 Reply 
 
Franlk Lund
R & D,
United Kingdom, Joined Apr 2005, 222

Franlk Lund

R & D,
United Kingdom,
Joined Apr 2005
222
11:45 Dec-06-2012
Re: Eddy current testing for welds
In Reply to creed at 04:48 Dec-06-2012 (Opening).

Creed,

1. The calibration slot starts from the inspection surface, so it gives a path for the interrogating current to penetrate into the test block by going down and up the flanks of the slot. If your slot is on the other side of the block, then the interrogating current in the slotless surface is not interrupted and will not see the slot.

2. Things get different when your 2mm deep vertical slot penetrates to the other side of the 2mm thick test piece. Of course, a slanted defect can have a 2mm pocket depth without penetrating a 2mm thick plate.

Cheers,
Frank

 
 Reply 
 
creed
NDT Inspector,
Vietnam, Joined Jul 2009, 37

creed

NDT Inspector,
Vietnam,
Joined Jul 2009
37
22:41 Dec-06-2012
Re: Eddy current testing for welds
In Reply to John Hansen at 10:32 Dec-06-2012 .

Thanks John and Franlk.
Your answers make me feel open-minded. Prior I had stupid perpective in checking thin material might affected to signal.
Cheers.

 
 Reply 
 

Product Spotlight

ISONIC 3510

Very Powerful Superior Performance Extremely Portable Smart Phased Array Ultrasonic Flaw Detector an
...
d Recorder with 2 Conventional UT and TOFD Channels uniquely combines PA, single- and multi-channel conventional UT, and TOFD modalities providing 100% raw data recording and imaging. Suitable for all kinds of every-day ultrasonic inspections
>

HARDNESS TESTER TKM-459CE combi

TKM-459CE combi applies 2 methods of hardness control: UCI and Leeb. It provides high-accuracy tes
...
ting of metals and alloys as well as items of different sizes and configurations, their hardened layers and galvanic coatings. Device represents results in HB, HRC, HV and others. Shock-, dust- and water-proof housing with intuitive software make this gauge easy to use in all working conditions.
>

CIVA 2020 UT Module

CIVA NDE Simulation Software is the world leader of NDT Simulation. The UT simulation Module incl
...
udes: - "Beam computation": Beam propagation simulation - "Inspection Simulation": Beam interaction with flaws or specimens The user can simulate a whole inspection process (pulse echo, tandem or TOFD) with a wide range of probes (conventional, Phased- arrays or EMAT), components, and flaws.
>

IntraPhase Athena Phased Array System

The Athena Phased Array system, manufactured by WesDyne NDE Products & Technology, consists of a pha
...
sed array acquisition system and PC running IntraSpect software. A PC is used to perform acquisition, analysis and storage of the data. System hardware is capable of operating up to four data sets with any combination of phased array or conventional UT probes. NOW AVAILABLE IN 64-64 CONFIGURATION.
>

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