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NOVO DR
develops and manufactures cutting edge Portable Digital Radiography X-ray Inspection Systems.

1109 views
03:44 Mar-01-2006

Dick Gray

Engineering,
Canada,
Joined Nov 1999
14
Digital radiography resolution

Has anyone published a side by side performance test of the various digital radiography systems? In general, automation, latitude, environmental concerns, cost reduction, data exchange etc. are mooted as reasons to switch to digital from film. All are valid reasons for change but I haven’t been able to match the performance of Class 1 films e.g. Kodak M. There are a number of technologies available from numerous manufacturers but often, resolution information is vague or missing. To date, I’ve found that 80 micron resolution is insufficient for my situations.

I’m interested in field applications so the equipment has to be rugged

Materials are carbon and stainless steels

The thickness range is from 0.25” to 2”

Thickness measurement capability via sectional views and density measurement are required to assess flow-assisted corrosion (FAC) and microbial induced corrosion (MIC)

Compliance to ASME Section III, Class 1 NB for weld inspection

DICONDE compliant

Can you suggest a technology or vendor with the “highest” resolution possible? One technology may not cope with all my applications and that’s fine.





    
 
07:03 Mar-01-2006
Tim B
Re: Digital radiography resolution ----------- Start Original Message -----------
: Has anyone published a side by side performance test of the various digital radiography systems? In general, automation, latitude, environmental concerns, cost reduction, data exchange etc. are mooted as reasons to switch to digital from film. All are valid reasons for change but I haven’t been able to match the performance of Class 1 films e.g. Kodak M. There are a number of technologies available from numerous manufacturers but often, resolution information is vague or missing. To date, I’ve found that 80 micron resolution is insufficient for my situations.
: I’m interested in field applications so the equipment has to be rugged
: Materials are carbon and stainless steels
: The thickness range is from 0.25” to 2”
: Thickness measurement capability via sectional views and density measurement are required to assess flow-assisted corrosion (FAC) and microbial induced corrosion (MIC)
: Compliance to ASME Section III, Class 1 NB for weld inspection
: DICONDE compliant
: Can you suggest a technology or vendor with the “highest” resolution possible? One technology may not cope with all my applications and that’s fine.
------------ End Original Message ------------

Just keep one thing in mind. If a vendor tells you you get a certain resiolution with their system, that's fine. However, remember one thing. If your monitor only has 525 Lines of Resolution, then guess what. You only have 525 lines of resolution. I don't care what the system has. It may have 1800 lines of resolution, but you only see 525 of them.




    
 
06:23 Mar-01-2006

John Brunk

Engineering, NDT Level III
Self employed, part-time,
USA,
Joined Oct 1999
158
Re: Digital radiography resolution ----------- Start Original Message -----------
: : Has anyone published a side by side performance test of the various digital radiography systems? In general, automation, latitude, environmental concerns, cost reduction, data exchange etc. are mooted as reasons to switch to digital from film. All are valid reasons for change but I haven’t been able to match the performance of Class 1 films e.g. Kodak M. There are a number of technologies available from numerous manufacturers but often, resolution information is vague or missing. To date, I’ve found that 80 micron resolution is insufficient for my situations.
: : I’m interested in field applications so the equipment has to be rugged
: : Materials are carbon and stainless steels
: : The thickness range is from 0.25” to 2”
: : Thickness measurement capability via sectional views and density measurement are required to assess flow-assisted corrosion (FAC) and microbial induced corrosion (MIC)
: : Compliance to ASME Section III, Class 1 NBfor weld inspection
: : DICONDE compliant
: : Can you suggest a technology or vendor with the “highest” resolution possible? One technology may not cope with all my applications and that’s fine.
: Just keep one thing in mind. If a vendor tells you you get a certain resiolution with their system, that's fine. However, remember one thing. If your monitor only has 525 Lines of Resolution, then guess what. You only have 525 lines of resolution. I don't care what the system has. It may have 1800 lines of resolution, but you only see 525 of them.
------------ End Original Message ------------

My company is using quite a variety of digital radiography equipment: CMOS panels with 80 micron pixels, miniature CMOS panel with 37 micron pixels, amorphous silicon panels with 125 micron pixels, computed radiography system (not the very latest) and image intensifiers. We still use a lot of film! Our best applications for solid state imaging are those where we can use a microfocus x-ray machine and projection-magnification to, in effect, reduce the pixel size by the amount of magnification we can use. Our microfocus machines are limited to 200 kV and lower and they are not portable, so that doesn't help much for a field application. I had hoped to use computed radiography for aluminum and steel castings with thicknesses ranging for 0.1 inch to 3 inches, but I have not been satisfied with the ability to evaluate shrinkage or any discontinuity that does not have a sharp edge. I understand others are using CR for castings but have no details. I have seen amorphous silicon panels used in a foundry for Grade C (lowest quality that requires radiography)aluminum castings and the images seemed adequate to me. For welds where projection-magnification was not practical I have been happier with CMOS for detail resolution. I certainly agree that the monitor is important. We generally refuse to e-mail images to desktop computers. John Pursley of Envison Product Design has presented at least one paper on meeting ASME weld inspection requirements with solid state panels. I think you can find it at www.cmosxray.com.




    
 
09:48 Apr-20-2006

Dick Gray

Engineering,
Canada,
Joined Nov 1999
14
Re: Digital radiography resolution Does anyone know of a vendor whose digital RT system can meet ASME Section III, Division 1, NB, Table NB-5111-1 when using isotopes e.g. Selenium or Iridium? The materials being examined are carbon, low allow and stainless steels.

----------- Start Original Message -----------
: Has anyone published a side by side performance test of the various digital radiography systems? In general, automation, latitude, environmental concerns, cost reduction, data exchange etc. are mooted as reasons to switch to digital from film. All are valid reasons for change but I haven’t been able to match the performance of Class 1 films e.g. Kodak M. There are a number of technologies available from numerous manufacturers but often, resolution information is vague or missing. To date, I’ve found that 80 micron resolution is insufficient for my situations.
: I’m interested in field applications so the equipment has to be rugged
: Materials are carbon and stainless steels
: The thickness range is from 0.25” to 2”
: Thickness measurement capability via sectional views and density measurement are required to assess flow-assisted corrosion (FAC) and microbial induced corrosion (MIC)
: Compliance to ASME Section III, Class 1 NB for weld inspection
: DICONDE compliant
: Can you suggest a technology or vendor with the “highest” resolution possible? One technology may not cope with all my applications and that’s fine.
------------ End Original Message ------------





    
 
08:25 Apr-28-2006

Nils Kah

Other, Sales Manager
DÜRR NDT GmbH & Co. KG,
Germany,
Joined May 2006
5
Re: Digital radiography resolution Maybe it´s interesting for you to know that our company is able to deliver a high resolution CR-Scanner with a minimum laser beam size of only 12,5 µm. Thus we can provide a system with a minimal detactability of 25µm.
The system is just in certifying process on BAM, Berlin. We will present the new system, called
HD-CR 35 NDT during the Control Sinsheim which takes place from 9th of May to 12th of May.
For further questions, please send me an eMail.

Kind regards,
Nils Kah
Dürr NDT





    
 


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