Dear all,

While doing Nozzle calculation with WRC107 im getting a warning that " Ratio of Pad Radius / Rm = 0.73 This is not between 0.01 and 0.571"


While doing Nozzle calculation with WRC297 (Same Vessel) im getting a warning that " Dn/ Tn = 15.336 < 20 Check the limitations in WRC bulletin 297"

Do it have any problem as my vessel has been fabricated?

Both WRC codes have limitations on their usage because of the range of the graphs given in both codes. If you're outside the scope of the code it depends on which side of the graph you are if the results are still reasonable or not.

while doing nozzle calculations using wrc 107/297 if we are outside the range of graphs then how to proceed with the calculations and how to validate the calculations

The more you are out of the range of WRC-107/297, the less accurate the results will be.

So, you should see the curve in the WRC-107/297 bulletins to check it.

You should also try the other methods, nozzle reinforcement, App. 1-10/1-7 for large nozzles, code minimum wall thickness, WRC-297, WRC-368 and most important your experience.

In my opinion, if the curves are not exceeded by much and if the stresses are well below the allowables then the design probably is ok. So, you have to utilize your prior design experience.

Otherwise, use a finite element analysis program to check that nozzle.

Another aspect of the issue is how accurate are your piping Loads :-) I am going there.

Dear All,

Which WRC bulletin incorporates the stress analysis of reinforced nozzle ?

Also which WRC is applicable for nozzle in conical head ?

You may want to check this site,

http://www.forengineers.org/pvrc/

Can we use width of reinforcement pad larger then limit given in UG-40 of ASME, for Local Load Analysis as per WRC107.

Yes Hirak,

You can use higher width pad, but for good results your pad size in design shall be such that you remain in curve value limitations of WRCB-107 graphs.

Mukesh

what are all the piping load cases are included in your WRC analysis? please listout the same.