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
D Wallace
,
USA, Joined Nov 2019, 2

D Wallace

,
USA,
Joined Nov 2019
2
10:44 Nov-09-2019
UT testing for Weld Overlay / Clad thickness

We need to determine the thickness of a heavy barrel nozzle, Base metal is a CR-Mo carbon steel, with internal Stainless steel overlay (Electroslag overlay) for corrosion resistance.
So far our readings are showing much higher than the design nominal.
But there are isolated areas with a lower amplitude reflector before the backwall. I'm not qualified or calibrated to determine if these are flaws

For equipment I'm using a flaw detector with A Scan, a 5 mhz dual probe. CS and SS step wedges. We do not have a welded/Overlay cal block, but would that alone be the answer to our problem?

Can this job be done with this equipment or no? Should I mention the reflectors at least? They could be flaws..

If i find a few spots where a reflector appears before the suspect backwall, could I use the time of flight function and use the two peak values to calculate both the base metal and the internal SS overlay thickness?

 
 Reply 
 
Michel Couture
NDT Inspector,
consultant, Canada, Joined Sep 2006, 894

Michel Couture

NDT Inspector,
consultant,
Canada,
Joined Sep 2006
894
17:52 Nov-11-2019
Re: UT testing for Weld Overlay / Clad thickness
In Reply to D Wallace at 10:44 Nov-09-2019 (Opening).

One of the rules for UT inspection is to calibrate using a bloc that has properties similar to what your are inspecting. Basically, you don't compare apples to oranges. So yes, you should use a CR-Mo carbon steel block with a SS overlay. Your problem will be to fabrication a block having an overlay with the same thickness as what you have on your barrel nozzle.

As for your reflector, if you know the exact thickness of the CR-Mo carbon steel of your nozzle, you should be able to determine the location of the reflector. It should tell you if it is located in the carbon steel, at the CS/SS interface or in the stainless steel.

 
 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.
>

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
>

Eddy Current inspection : RotoETscan Rotating Head

The rotating head RotoETscan detects the presence of longitudinal surface or sub surface defects a
...
t high speed. The rotating head is often installed directly on the production line. It is generally dedicated to the control of long products such as tubes, bars and wires, made of ferrous or non-ferrous material. It can also be used for inspection of small parts (billets).
>

Research Center IDEKO develops an ultrasonic train wheel inspection system for CAF

The Basque Research centre IK4-IDEKO has developed a state-of-the-art ultrasonic inspection system f
...
or the train wheel. This system secures a sound condition of train wheels and is thus a significant contribution to rail transport safety. The device was delivered to CAF recently and its use allows the manufacturer to become an approved supplier of rolling stock in Italy, as it meets the demanding homologation standards of this country. \\\\r\\\\n
>

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