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 -

1660 views
Technical Discussions
Chris Coughlin
Chris Coughlin
01:06 Oct-18-2001
Dry-coupled UT transducers

Hi All;

TRI/Austin is looking for "dry coupled" ultrasonic transducers in the 1-5 MHz range that generate shear waves. Our application is a pretty tight fit, and ideally we're looking for fluid-filled wheels or similar configurations. Any and all help is appreciated; more info on the RFI is available from http://www.ntiac.com/rfi.html. Please note we're not interested in alternative NDE techniques or transducers (e.g. EMATs) at this stage.

Thanks!
Chris



 
 Reply 
 
Kelly Phelps
Consultant, IT Manager/Marketing Manager
NDT Engineering Corporation, USA, Joined Oct 2001, 6

Kelly Phelps

Consultant, IT Manager/Marketing Manager
NDT Engineering Corporation,
USA,
Joined Oct 2001
6
06:23 Nov-02-2001
Re: Dry-coupled UT transducers
: Hi All;
.
: TRI/Austin is looking for "dry coupled" ultrasonic transducers in the 1-5 MHz range that generate shear waves. Our application is a pretty tight fit, and ideally we're looking for fluid-filled wheels or similar configurations. Any and all help is appreciated; more info on the RFI is available from http://www.ntiac.com/rfi.html. Please note we're not interested in alternative NDE techniques or transducers (e.g. EMATs) at this stage.
.
: Thanks!
: Chris
.

Are you looking for dry-coupled roller probes? By what you describe this is what I am guessing.


 
 Reply 
 
Chris Coughlin
Chris Coughlin
06:55 Nov-02-2001
Re: Dry-coupled UT transducers
: : Hi All;
: .
: : TRI/Austin is looking for "dry coupled" ultrasonic transducers in the 1-5 MHz range that generate shear waves. Our application is a pretty tight fit, and ideally we're looking for fluid-filled wheels or similar configurations. Any and all help is appreciated; more info on the RFI is available from http://www.ntiac.com/rfi.html. Please note we're not interested in alternative NDE techniques or transducers (e.g. EMATs) at this stage.
: .
: : Thanks!
: : Chris
: .
.
: Are you looking for dry-coupled roller probes? By what you describe this is what I am guessing.
.


Yes, we're mainly interested in dry-coupled roller probes, but we haven't been able to find any yet that will support shear wave modes.


 
 Reply 
 
Ed Ginzel
R & D, -
Materials Research Institute, Canada, Joined Nov 1998, 1307

Ed Ginzel

R & D, -
Materials Research Institute,
Canada,
Joined Nov 1998
1307
07:16 Nov-02-2001
Re: Dry-coupled UT transducers
: : : Hi All;
: : .
: : : TRI/Austin is looking for "dry coupled" ultrasonic transducers in the 1-5 MHz range that generate shear waves. Our application is a pretty tight fit, and ideally we're looking for fluid-filled wheels or similar configurations. Any and all help is appreciated; more info on the RFI is available from http://www.ntiac.com/rfi.html. Please note we're not interested in alternative NDE techniques or transducers (e.g. EMATs) at this stage.
: : .
: : : Thanks!
: : : Chris
: : .
: .
: : Are you looking for dry-coupled roller probes? By what you describe this is what I am guessing.
: .
.
:
: Yes, we're mainly interested in dry-coupled roller probes, but we haven't been able to find any yet that will support shear wave modes.
.
Do you REALLY mean that the dry-coupled roller must support Shear mode, as in SH shear wave inspection?
To accomplish this as a "coupling medium" you would still need a nonNewtonian viscous fluid to then couple the SH mode from the roller into the workpiece if using a piezo-element. Even with good SH shear coupling materials (like honey) you are likely to struggle to maintain a constant quality of coupling. It is hard enough to do this in a static condition let alone trying to do so on a dynamic scan.
I would think that most shear wave applications would use SV shear so you would rely on mode conversion from compression waves and the reverse (SV to compression) just as is done when using standard plastic refracting wedges.

Otherwise, if it is SH mode you require perhaps EMATs might be the only option.

Ed



 
 Reply 
 
Kelly Phelps
Consultant, IT Manager/Marketing Manager
NDT Engineering Corporation, USA, Joined Oct 2001, 6

Kelly Phelps

Consultant, IT Manager/Marketing Manager
NDT Engineering Corporation,
USA,
Joined Oct 2001
6
07:52 Nov-02-2001
Re: Dry-coupled UT transducers
: : : : Hi All;
: : : .
: : : : TRI/Austin is looking for "dry coupled" ultrasonic transducers in the 1-5 MHz range that generate shear waves. Our application is a pretty tight fit, and ideally we're looking for fluid-filled wheels or similar configurations. Any and all help is appreciated; more info on the RFI is available from http://www.ntiac.com/rfi.html. Please note we're not interested in alternative NDE techniques or transducers (e.g. EMATs) at this stage.
: : : .
: : : : Thanks!
: : : : Chris
: : : .
: : .
: : : Are you looking for dry-coupled roller probes? By what you describe this is what I am guessing.
: : .
: .
: :
: : Yes, we're mainly interested in dry-coupled roller probes, but we haven't been able to find any yet that will support shear wave modes.

The problem is that at a shear wave angle, both the thickness of the roller material and the dead air space that might be encountered at the point that the roller curves up off the surface of the part being inspected, would provide too much attenuation. However, a tractor wheel design that keeps the shear wave flat to the surface would work, provided that the rubber tracks are thin enough to transmit sound.


 
 Reply 
 
Chris Coughlin
Chris Coughlin
08:17 Nov-02-2001
Re: Dry-coupled UT transducers
: : : : : Hi All;
: : : : .
: : : : : TRI/Austin is looking for "dry coupled" ultrasonic transducers in the 1-5 MHz range that generate shear waves. Our application is a pretty tight fit, and ideally we're looking for fluid-filled wheels or similar configurations. Any and all help is appreciated; more info on the RFI is available from http://www.ntiac.com/rfi.html. Please note we're not interested in alternative NDE techniques or transducers (e.g. EMATs) at this stage.
: : : : .
: : : : : Thanks!
: : : : : Chris
: : : : .
: : : .
: : : : Are you looking for dry-coupled roller probes? By what you describe this is what I am guessing.
: : : .
: : .
: : :
: : : Yes, we're mainly interested in dry-coupled roller probes, but we haven't been able to find any yet that will support shear wave modes.
.
: The problem is that at a shear wave angle, both the thickness of the roller material and the dead air space that might be encountered at the point that the roller curves up off the surface of the part being inspected, would provide too much attenuation. However, a tractor wheel design that keeps the shear wave flat to the surface would work, provided that the rubber tracks are thin enough to transmit sound.
.


Right, that's pretty much the same conclusion we had come to for the transducers. We're hoping to find some COTS transducers, rather than (pun intended) reinvent the wheel.


 
 Reply 
 
Kelly Phelps
Consultant, IT Manager/Marketing Manager
NDT Engineering Corporation, USA, Joined Oct 2001, 6

Kelly Phelps

Consultant, IT Manager/Marketing Manager
NDT Engineering Corporation,
USA,
Joined Oct 2001
6
08:36 Nov-02-2001
Re: Dry-coupled UT transducers
: Right, that's pretty much the same conclusion we had come to for the transducers. We're hoping to find some COTS transducers, rather than (pun intended) reinvent the wheel.


It really wouldn't be hard to design since we already make several types of roller probes. The question is what you would use for the rubber track.



 
 Reply 
 
Ken Camplin
, Joined ,

Ken Camplin

,
Joined

00:39 Nov-02-2001
Re: Dry-coupled UT transducers
: : : : Hi All;
: : : .
: : : : TRI/Austin is looking for "dry coupled" ultrasonic transducers in the 1-5 MHz range that generate shear waves. Our application is a pretty tight fit, and ideally we're looking for fluid-filled wheels or similar configurations. Any and all help is appreciated; more info on the RFI is available from http://www.ntiac.com/rfi.html. Please note we're not interested in alternative NDE techniques or
transducers (e.g. EMATs) at this stage.
: : : .
: : : : Thanks!
: : : : Chris

: : : .
: : .
: : : Are you looking for dry-coupled roller probes? By what you describe this is what I am guessing.
: : .
: .
: :
: : Yes, we're mainly interested in dry-coupled roller probes, but we haven't been able to find any yet that will support shear wave modes.
: .
: Do you REALLY mean that the dry-coupled roller must support Shear mode, as in SH shear wave inspection?
: To accomplish this as a "coupling medium" you would still need a nonNewtonian viscous fluid to then couple the SH mode from the roller into the workpiece if using a piezo-element. Even with good SH shear coupling materials (like honey) you are likely to struggle to maintain a constant quality of coupling. It is hard enough to do this in a static condition let alone trying to do so on a dynamic scan.
: I would think that most shear wave applications would use SV shear so you would rely on mode conversion from compression waves and the reverse (SV to compression) just as is done when using standard plastic refracting wedges.
.
: Otherwise, if it is SH mode you require perhaps EMATs might be the only option.
.
: Ed
.
Hello Chris:

I know you orinally said you were not looking at EMATs, but I am sure you know that EMATs are particularly well suited for generating shear waves, especially SH waves. EMATs have come along way lately and have been fielded in very harsh enviroments and in automated fashion. If you would like to know more about our EMAT systems, please visit us at www.innerspec.com.


 
 Reply 
 

Product Spotlight

Ultrasonic Probe Recharacterization Service

NDT Systems offers a comprehensive Aftercare and Recharacterization Service for all our ultrasonic
...
probes. The Recharacterization Service is fully compliant with International ASTM E1065 Standard Guide (and other applicable standards) and offers complete documentation, traceable to the ASTM E1065 Standard. For more details or to schedule Recharacterization Services contact ndtsales@ndtsystems.com
>

IRIS 9000Plus - Introducing the next generation of heat exchanger inspection.

Representing the seventh generation of the IRIS system, the IRIS 9000 Plus has nearly 200 years of c
...
ombined field inspection experience incorporated in its design. This experience combined with a strong commitment to quality and a history of innovation has made Iris Inspection Services® the undisputed leader in IRIS technology.
>

FMC/TFM

Next generation for Phased Array UT is here now with FMC/TFM! Have higher resolution imaging, impr
...
oved signal to noise ratio, characterize, size and analyze defects better with access to several wave mode views and save raw FMC data for higher quality analysis.  Some of the benefits are:
  • Beautiful Image! Easier to understand what you're looking at
  • Completely focused in entire image or volume
  • Much easier to define setups before inspection
  • Easier to decipher geometry echoes from real defects
  • Oriented defects (e.g. cracks) are imaged better
  • See image from different wave modes from one FMC inspection
  • FMC data can be reprocessed/analyzed without going back to the field
>

Micro CT

nanoVoxel series has nano-scale resolution upto 500nm by using high voltage X-ray source (from 80-
...
300 kV) with micro/nano focal spot and highly sensitive flat panel detectors and unique Optical coupling detector.
>

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