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 -

364 views
Technical Discussions
Chris Bland
Consultant, Manager
CGSB, Canada, Joined Sep 2002, 1

Chris Bland

Consultant, Manager
CGSB,
Canada,
Joined Sep 2002
1
00:10 Sep-13-2002
ASME calibration

I have carried out a great many ultrasonic examinations in accordance with ASME B & PV codes but have to confess that I have never calibrated for distance (or Sweep Range, as ASME calls it) using the methods recommended by ASME V, Article 4, Appendix B, since I was taught to use the IIW block to calibrate an ultrasonic instrument and only use the ASME basic block to establish sensitivity. It has been my experience that responses from basic blocks vary considerably, depending on the skill of the machine shop that fabricated them, and this alone can impact the accuracy and repeatability of inspections.

I would be interested to know if it is common practice by others to use the ASME calibration procedure and how practical it is to work with. Since the screen is calibrated in arbitrary units (e.g. 2 on the baseline represents 1/8 of the beam path)how are accurate measurements recorded on the report? Furthermore, how can one take adventage of the trig functions built into digital flaw detectors, that make it so simple to calculate surface distance, depth etc?

About the only advantage I can see of relying on the basic block is that it would make it possible to calibrate for distance using contoured wedges - something that is impossible to do on a flat block - or does anyone know any tricks for doing this?


    
 
 
ayman ahmed
ayman ahmed
07:56 Oct-30-2002
Re: ASME calibration

: I have carried out a great many ultrasonic examinations in accordance with ASME B & PV codes but have to confess that I have never calibrated for distance (or Sweep Range, as ASME calls it) using the methods recommended by ASME V, Article 4, Appendix B, since I was taught to use the IIW block to calibrate an ultrasonic instrument and only use the ASME basic block to establish sensitivity. It has been my experience that responses from basic blocks vary considerably, depending on the skill of the machine shop that fabricated them, and this alone can impact the accuracy and repeatability of inspections.
.
: I would be interested to know if it is common practice by others to use the ASME calibration procedure and how practical it is to work with. Since the screen is calibrated in arbitrary units (e.g. 2 on the baseline represents 1/8 of the beam path)how are accurate measurements recorded on the report? Furthermore, how can one take adventage of the trig functions built into digital flaw detectors, thatmake it so simple to calculate surface distance, depth etc?
.
: About the only advantage I can see of relying on the basic block is that it would make it possible to calibrate for distance using contoured wedges - something that is impossible to do on a flat block - or does anyone know any tricks for doing this?
.and ihave not standred thk.of the range example:
ihave 29mm.thk. as acalibration block, are that cover26mm.thk.?



    
 
 

Product Spotlight

Compact NDT inspection-heads for measurements with active thermography

The compact inspection head is suitable for thermographic ndt tasks. The uncooled infrared camera
...
is specially developed for NDI-tasks and offers a thermal sensitivity until now known only from thermal imagers with cooled detector. All required components and functions are integrated into the inspection-head. You will only need an ethernet cable to connect the sensor with the evaluation system.
>

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.
>

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.
>

Mentor UT – Ultrasonic Phased Array Flaw Detector

With Mentor UT, you get an accessible and efficient inspection experience. Create user-defined menus
...
and workflows (“apps”) with GE’s desktop software Mentor Create to ensure consistency, even for the most complex inspections, every time. Mentor UT is the first UT device to easily allow wireless connectivity and live streaming, so you get second opinions when you need them most—in real-time.
>

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
s