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 -
941 views
Technical Discussions
Jeff
NDT Inspector
Nucor Steel, USA, Joined Apr 2005, 6

Jeff

NDT Inspector
Nucor Steel,
USA,
Joined Apr 2005
6
01:54 Aug-10-2004
Surface waves

I work for a steel company. They want to know if I can inspect steel plate for cracks running transverse along the plate surface. One problem scale is on the surface. I was wondering if surface waves would penetrate the scale and give me the surface indications I am looking for. These defects are not very deep. Our customers are finding these defcts after the scale is blown off. If uktrasound is not the answer give me some ideas. I have already kicked around MT and PT butspeed is not in their favor.

Jeff Medford


 
 Reply 
 
Guest
Guest
03:26 Aug-10-2004
Re: Surface waves
Try the ACFM (Alternating Current Field Measurement) technique for detection.
----------- Start Original Message -----------
: I work for a steel company. They want to know if I can inspect steel plate for cracks running transverse along the plate surface. One problem scale is on the surface. I was wondering if surface waves would penetrate the scale and give me the surface indications I am looking for. These defects are not very deep. Our customers are finding these defcts after the scale is blown off. If uktrasound is not the answer give me some ideas. I have already kicked around MT and PT butspeed is not in their favor.
: Jeff Medford
------------ End Original Message ------------




 
 Reply 
 
Christopher Dragan
Engineering
ITWL, Poland, Joined Nov 2002, 3

Christopher Dragan

Engineering
ITWL,
Poland,
Joined Nov 2002
3
07:53 Aug-11-2004
Re: Surface waves
How deep this cracks are? If they are limited to 3 - 4 mm you can succesfully use eddy current technique. If this cracks running along plate surface that should be quite good visible.


 
 Reply 
 
Godfrey Hands
Consultant,
PRI Nadcap, United Kingdom, Joined Nov 1998, 305

Godfrey Hands

Consultant,
PRI Nadcap,
United Kingdom,
Joined Nov 1998
305
09:51 Aug-11-2004
Re: Surface waves
----------- Start Original Message -----------
: I work for a steel company. They want to know if I can inspect steel plate for cracks running transverse along the plate surface. One problem scale is on the surface. I was wondering if surface waves would penetrate the scale and give me the surface indications I am looking for. These defects are not very deep. Our customers are finding these defcts after the scale is blown off. If uktrasound is not the answer give me some ideas. I have already kicked around MT and PT butspeed is not in their favor.
: Jeff Medford
------------ End Original Message ------------

Jeff,
Surface waves should propagate underneath a layer of scale, but cannot be generated through them with conventional contact or immersion techniques using piezo transducers.
In immersion, the surface wave will continuously "leak" back out into the couplant liquid (water) and become very inefficient.

If the waves could be generated at the sides of dry plates, they could potentially propagate right across the plates if the frequency is low enough.

Another method using surface waves is to generate the surface wave using the EMAT technique, where the sound pulse is generated on the surface of the plate through the scale. Not many NDT companies are dong this however.

What depth of crack are you looking for?

Godfrey Hands




 
 Reply 
 

Product Spotlight

NDT.net launches mobile-friendly design

NDT.net has revamped its website providing a mobile-friendly design.The front page received a comp
...
letely new design and all other sections are now reacting responsively on mobile devices. This has been a major step to make our website more user- friendly.
>

Wireless TOFD scanner

Quick, accurate and highly reproducible welds testing. The System operates wirelessly and is compat
...
ible with any type of Windows based Laptop, Desktop or Tablet.
>

Research and Application Development For NDT

Acuren’s Research and Application Development specializes in the development of advanced ultraso
...
nic inspection techniques and systems for challenging inspection applications, with an emphasis on practical solutions which are field deployable. Services include manual and automated ultrasonic inspection system development, inspection technique optimization using laboratory scale studies and ultrasonic modeling (CIVA, BeamTool), preparing technical justification for technique evaluation and qualification (Probability of Detection and sizing accuracy studies), inspection/calibration/analysis procedure preparation to support field deployment of custom techniques, and development of custom imaging algorithms to support challenging inspection applications.
>

YXLON Cougar EVO

Scalable small footprint X-ray inspection systems for assembly and laboratory applications. The
...
YXLON Cougar EVO series was designed to provide the "best-in- class" inspection solutions for SMT, semiconductor, and laboratory assembly applications, while maintaining a small system footprint for maximum convenience. With optimized software and hardware, these systems produce higher quality and more consistent results than other electronics inspection systems currently on the market.
>

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