Radiography

http://www.acronymfinder.com/IQI.html

Dear Msurendra,

IQI -Image quality indication are mainly two types:-

1) holetype - ASTM E-1025

2) wire type - ASTM E747-97 ,EN 462-1

wire type IQI mostly used for pipe line welding radiography . the selection of IQI should be to achieve 2% sensitivity . for selecting wire thickness , pipe wall thickness plus the max. permissible weld crown height as per applicable code should be considered . sensitivity %= (wire thickness/ wall thickness + weld crown height)

with regrads

Depending on the Code in force for the project (which you should have a copy, or your home office should definitely have a copy), that code will specify which IQI size (and type) is applicable for any given thickness material. Plus, there are other considerations that the Code will cover with regard to radiography. Are you perhaps using an API Code? Check it out with your employer before you start.