Difference between Joint efficiency and quality factor 1

[kyong]

When we calculate required minimum thickness, we use E value which ranges around 0.5 to 1. In some formula, it is called joint efficiency, other formula refers it quality factor. What is the conceptual difference? Could anyone explain?

kyong

 

[prex]

A joint efficiency typically refers to welded joints, a quality factor to some classes of materials (castings, but also piping products in piping codes). They are used quite the same way, however a joint efficiency is normally taken as 1 in calculations where the joint is not involved (reinforcement of openings not crossing the joint). prex
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[rustbuster1]

"Joint efficiency" used for thickness/stress calculation is stipulated for different levels of inspection/quality of welds.
"Quality factor" applies to castings and as stated above conceptually works the same way (welds are castings after all). Interestingly it does not apply to GRAY CAST IRON. The more/higher level of inspection done to verify freedom from harmful flaws, the higher the allowable stress value for calculation of thickness or strength.

 

[Pras]

Kyong,
The conceptual diffrenece between the 'quality factor' and 'weld efficiency' is explained by Prex and rustbuster1.
In cases of calculations of casting welded joints, both the 'quality factor' of casting and 'weld efficiency' factors are involved. In such cases, as per ASME Sec VIII Div I Clause UG-24, the lesser of the two is to be applied but not both.
Hope this will help.

 

[MarkCopland]

main question..????..
There is not way to change a 100% radiographic examination in asme div2 for a steel casting?....that mean... for any casting a 100% Radiographic apply?....