UG-45 Minimum Thickness

[tzh0044]

This might be an elementary question but I'm new to the industrial and would like some help understanding UG-45.

I'm having trouble understanding why when determining what t_b why you pick the min(tb3,max(tb1,tb2)?
If you calculate tb1 or tb2 to be greater than the values listed in the tables why would you pick the lower value vs the higher calculated value?


Thanks.

 

[tzh0044]

My understanding is the higher allowable values listed in SEC II-D are when slight deformation is acceptable. These values exceed 2/3*Y but not 9/10*Y. But even if you used the higher allowable why does the code still pick the lower thickness value?

 

[XL83NL]

QUESTION FOR BETTER UNDERSTANDING.

WHY TWO ALLOWABLE STRESS (LOWER AND HIGHER) FOR SS AND LAS METALLURGY IN SEC II PART D.

Can you rephrase (preferably without using CAPS LOCK - not that thats the real issue) that? Not sure what you mean.

 

[Geoff13]

You can find any number of threads about UG-45 in this forum, but I find JTE's responce in this thread the most useful.

thread794-392918