Nozzle Loads - Expansion Case 1

[tutajrobert]

Dear Forum Users,
I'm a novice engineer and I'm calculating nozzle loads in AutoPipe. I searched and read a lot of topics about which load conditions take into consideration to calcualte nozzle loads, but I've still got one question.
There's no doubt that I have to check nozzles due to SUS and OPE conditions. But what about EXP loads? Should I check it due to EXP conditions too? EXP loads are very high and nearly 20 times exceed allowable loads. I know that EXP loads are more or less "internal thermal" forces in pipes and in my opinion I should consider only maximum displacements (if any). But are vendors able to deliver me allowable displacements on equipment? I'd like to do my job as carefully as it is possible - maybe it's too conservative attempt. What do you think?

I'll be grateful for your responses, because I'm really stuck with this problem.
Robert

 

[TGS4]

You need to use the nozzle loads that the pressure vessel nozzle will experience in the design and operating condition. If I assume that you are applying the ASME Code for this type of work, then for calculating the stresses in the nozzle and vessel shell, you will be applying some type of simplified analysis, such as WRC107 (which only calculates the stresses in the cardinal-directions in the shell). You will also need to evaluate/classify those stresses, and the most common approach for that is through ASME Section VIII, Division 2, Part 5 - Table 5.6.

There, for any shell near a nozzle, and for the net-section axial force and/or bending moment applied to the nozzle (note that there is no differentiation here between gravity loads and thermal expansion loads) the classifications are as follows: local membrane: PL, Bending: Q, Peak: F. So, it is the total design load for determining Protection Against Plastic Collapse, and the operating load range for determining Protection Against Ratcheting.