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 -
444 views
Technical Discussions
Peter Hammond
Peter Hammond
07:13 Sep-24-1996
High temperature probes

Hello,
I have a couple of questions arising from Klaus Matthies' paper.
First, what is LNN? What are the advantages/disadvantages compared
with LiNbO3, also mentioned?

Second, is this probe intended to be used similarly to a normal probe,
carried around and put onto hot surfaces for a few seconds? Is thermal
shock not a problem here? The devices I have read about
previously have been permanently mounted, for condition
monitoring.



 
 Reply 
 
K. Matthies
K. Matthies
03:30 Sep-27-1996
Re: High temperature probes
makes sense to
heat them up slowly in order to allow for a balanced heat flow. (approx.
10 min./100 degrees centigrade).


Best regards,

K. Matthies




 
 Reply 
 
K. Matthies
K. Matthies
02:38 Oct-04-1996
Re: High temperature probes
Dear Mr. Hammond,

The LNN piezo ceramic are developed in a project financed by EC research programme. In the same project, we have made further development in the transducer. The report that you find in the workshop is practically the final report.

It is true that these transducers are used in applications which requires large inspection time. We also use these transducers for determining wall thickness in Zinc coating plants. We measure the wall thickness by immersion technic in approximately 450 °C hot Zinc.

For your requirement, we have developed other type of transducers. As far as the construction of these transducers are concerned, it is similar to the previous one except that these are housed in plastic material. They are suitable only for continuous application up to 200 °C.

Since they posses ceramic delay path, it is possible to use these transducers on hot surfaces upto 1000 °C. However, this is possible in time intervals of 10 sec with 50 sec pause.

With best regards

K. Matthies



 
 Reply 
 
Peter Hammond
Peter Hammond
01:51 Oct-04-1996
Re: High temperature probes
Dear Mr Matthies,
Thankyou for your reply to my post.

I was aware that Ferroperm were working on LiNbO3 ceramics but I did not
know they were so near to success.

Your description of slow heating to high temperature is much as I
expected. Effectively this would tend to limit application to continuous
monitoring, surely? This is of course a very valuable task, but wouldn't
it be nice to be able to use the probe fully portably?

Best regards,
Dr Peter Hammond,
Cygnus Intruments.

: Dear Mr. Hammond,

: The LNN piezo ceramic are developed in a project financed by EC research programme. In the same project, we have made further development in the transducer. The report that you find in the workshop is practically the final report.

: It is true that these transducers are used in applications which requires large inspection time. We also use these transducers for determining wall thickness in Zinc coating plants. We measure the wall thickness by immersion technic in approximately 450 °C hot Zinc.

: For your requirement, we have developed other type of transducers. As far as the construction of these transducers are concerned, it is similar to the previous one except that these are housed in plastic material. They are suitable only for continuous application up to 200 °C.

: Since they posses ceramic delay path, it is possible to use these transducers on hot surfaces upto 1000 °C. However, this is possible in time intervals of 10 sec with 50 sec pause.

: With best regards

: K. Matthies




 
 Reply 
 
K. Matthies
K. Matthies
01:53 Oct-04-1996
Re: High temperature probes
Because the probes have in their front only a thin Lambda/2-diaphragm, it makes sense to
heat them up slowly in order to allow for a balanced heat flow. (approx.
10 min./100 degrees centigrade).


Best regards,

K. Matthies

: Dear Mr Matthies,
: Thankyou for your reply to my post.

: I was aware that Ferroperm were working on LiNbO3 ceramics but I did not
: know they were so near to success.

: Your description of slow heating to high temperature is much as I
: expected. Effectively this would tend to limit application to continuous
: monitoring, surely? This is of course a very valuable task, but wouldn't
: it be nice to be able to use the probe fully portably?

: Best regards,
: Dr Peter Hammond,
: Cygnus Intruments.

: : Dear Mr. Hammond,

: : The LNN piezo ceramic are developed in a project financed by EC research programme. In the same project, we have made further development in the transducer. The report that you find in the workshop is practically the final report.

: : It is true that these transducers are used in applications which requires large inspection time. We also use these transducers for determining wall thickness in Zinc coating plants. We measure the wall thickness by immersion technic in approximately 450 °C hot Zinc.

: : For your requirement, we have developed other type of transducers. As far as the construction of these transducers are concerned, it is similar to the previous one except that these are housed in plastic material. They are suitable only for continuous application up to 200 °C.

: : Since they posses ceramic delay path, it is possible to use these transducers on hot surfaces upto 1000 °C. However, this is possible in time intervals of 10 sec with 50 sec pause.

: : With best regards

: : K. Matthies




 
 Reply 
 

Product Spotlight

HD-CR 35 NDT Computed Radiography System

Portable high-resolution CR scanner for all radiography applications - weld testing, profile images
...
and aerospace. No matter what type of radiographic testing you are performing, the unique TreFoc Technology of the HD-CR 35 NDT imaging plate scanner always guarantees the highest image quality.
>

Cygnus 6+ PRO Multi-Mode Ultrasonic Thickness Gauge

The Cygnus 6+ PRO thickness gauge is the most advance gauge within the Cygnus range with key featu
...
res including: comprehensive data logging; A-scan and B-scan display; manual gain control; Bluetooth connectivity; and much more. With its unique dual display and three measuring modes (Multiple-Echo, Echo-Echo and Single-Echo), this surface thickness gauge offers maximum versatility for inspections.
>

Teletest Focus+

Teletest Focus+ electronics have superior capabilities than rivals on the market. Beyond the usual
...
test features, Focus+ has 24 transmit channels and 24 receive channels, with an additional on-board switching capabilities. The instrument's frequency range is 10–300 kHz.
>

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
>

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