IQI Material

[QC7]

Hi Team,

Whether I can use SS material IQI on Inconel radiography?? !!

Which material is less radiation absorption material,if comparing between SS and Inconel??


Regards,

 

[stanweld]

You need to use Inconel IQI. Stainless steel is less absorbant. Based on an approximate radiographic equivalence factor for steel and stainless steel of 1.0, Inconel is 1.3 using Iridium 192. Reference, Nondestructive Handbook, Volume 4, Radiographic Testing

 

[QC7]

It's means that SS IQI also can be used for Inconel RT,based on the Sec V para T 276.1.Its saying that IQI can use if ''IQI grade with less radiation absorption than the material being radiographed''.

Am i correct or not?? !!

 

[stanweld]

Per ASME V, Article you may use the steel. Do you really want to? You may not see the minimum wire, or hole size.

 

[QC7]

Ok, now i understood the concept.

Apart from above,Can you just explain more about approximate radiographic equivalence factor for steel,stainless steel and Inconel by using X ray as well as Cobalt 60.Whether its will same as like Ir192 ?

 

[stanweld]

It changes dramatically with very high (4-25 Mev) x-ray at which Inconel and Stainless and carbon steel become essentially equal. The differential remains the same for all gamma sources.

 

[JR97]

QC7

Here is link to the Kodak RT theory. An oldie but a goodie. The answers to your questions are all in here and it is written to a very understandable level.

http://www.kodak.com/eknec/documents/87/0900688a802b3c87/Radiography-in-Modern-Industry.pdf

JR97

 

[QC7]

Hi Team,

I would like to clear one of my doubt regarding improtance of IQI material?

Whether is there any difference between "FE" ans "SS" IQI wire?

Why some time client asking "SS" IQI wire for RT ?


QC7

 

[QC7]

Dear Team,


what is the difference between wire IQI "6 FE EN" and "6 SS EN"? .Why two different IQI materials are available even-though both are in same group ?

Is there any purpose for "6 SS EN" compare to " 6 FE EN" ?

 

[ndeguy]

QC7

"Fe" denotes the wires used are of low carbon steel, "SS" that the wires are of stainless steel (CrNi). These materials have different radiation absorption characteristics. You write that they "...are in the same group" What do you mean, from where do you take your information? Make a simple experiment and place the IQI's adjacent on a radiographic fim and make an exposure and compare the different densities of each IQI image.

 

[QC7]

Dear ndeguy,

Pls go through SE-747 for "MATERIAL GROUPING CLASSIFICATION OF WIRE IMAGE QUALITY INDICATORS (IQI) USED FOR RADIOLOGY"

As per SE-747,Materials have been designated in eight groups based on their radiographic absorption characteristics:groups 03, 02, and 01 for light metals and groups 1 through 5 for heavy metals.And as per Materials Group 1: Image quality indicators (IQIs) shall be made of carbon steel or Type 300 series stainless steel.

My conclusion is that "SS" and "Fe" IQI in RT is not that much significant difference .And availability of "SS" wire IQI is only for extensive application and not for any 'code' requirments.