Hi Experts

with reference to the above subject i noted that 107 and 297 tabs in WRC107/297 calculator. i am bit confusing with 297tab here, Since Caesar-II already checked the nozzle flexibility using WRC297 in error check. So as i understand that my subsequent step is to estimate the vessel stress due to the nozzle loads using WRC 107.

may i know the reason to have 297 calculation tab here? and on what case i should use this?

Thanks & Regards
Baskar

Helo experts,

any one can help me?

From CAESAR II UG,

WRC 107 :"....used to compute the stresses at both the inner and outer surfaces of the vessel wall,...."

WRC 297:"...WRC 297 also computes stresses in the nozzle and the vessel. (WRC 107 only computes stresses in the vessel.)..."
CAESAR II calculates the stress components at the four locations on the vessel around the nozzle and also the corresponding locations on the nozzle.

If you have modeled Nozzle as WRC 297 that means you have considered nozzle to be flexible. Hence WRC 107 cannot be applied (WRC 107 implies nozzle is rigid).

You should understand the error report generated upon selecting nozzle as WRC 297 shows nozzle flexibility (finite stiffnesses) not stresses.

Dear Sir,

thank you for your reply, but i have a doubt with refernce to the attachement CAESAR II App Guide. in which the nozzle is modeled as per WRC297 and the nozzle calculaiton is done at end of error checking, later in conclusoin page it is referred to the WRC107 to check the vessels stresses due to nozzle loads.

from your message i understand the same that if the nozzle is modeled as per WRC297, the WRC107 is not apllicable to the nozzle but not the vessel stress calcualtion right?

The WRC297 nozzle stiffness calculation is being done at end of error checking.. further to this do we required to run the WRC297 analysis which i found in the Analysis menu?.

Dear sir,

Any mistakes in my queries please explain me

There are two parts to addressing a vessle nozzle: (1) nozzle stiffnesses for the stress (flexilbility) analysis, and (2) local stress evaluation after the stress analysis.

In CAESAR II there are three methods available for determining the nozzle stiffnesses on a shell (based on the type of nozzle): (1) API-650 for nozzles on API tanks, (2) WRC-297 and (3) PD-5500 for nozzles on pressure vessels. At this point, all you get here are the stiffnesses used in the stress analysis.

Following the stress analysis you must take the resulting loads on the nozzle and perform an additional evaluation to determine if these loads exceed the permitted loads at the nozzle/vessel interface. For this, you can use (depending on the nozzle type): API-650, PD-5500, WRC-107, or WRC-297. Note that WRC-107 does not provide stiffnesses. This is why in the CAESAR II documentation WRC-297 is used at the input stage, and WRC-107 was used (in this specific example) for the subsequent local evaluation.