Dear Sir,

I have to do local load analysis for a 10” NB nozzle (Radial), which located on a cylindrical shell. So, I preferred to do WRC 297 instead of WRC 107.
Now for given loads my nozzle is unsafe in WRC 297 (Stresses at the edge of the pad becomes much high), while the same is safe in WRC 107. So, to be safe in WRC 297, i need to reduce the loads upto 30% of given loadings. I m confused which bulletin to follow (107 or 297)?

Dimensions are as follows,

Input Echo, WRC297 Item 5, Description: 10" NB

Diameter Basis for Cylindrical Shell Vbasis ID
Corrosion Allowance for Shell Cas 3.0000 mm
Shell Diameter Dv 4000.000 mm
Shell Thickness Tv 15.0000 mm
Shell Stress Concentration Factor Scfn 1.000

Diameter Basis for Nozzle Nbasis ID
Corrosion Allowance for Nozzle Can 3.0000 mm
Nozzle Diameter Dn 242.926 mm
Nozzle Thickness Tn 15.0622 mm
Nozzle Stress Concentration Factor Scfv 1.000

Diameter of Reinforcing Pad Dpad 496.000 mm
Thickness of Reinforcing Pad Tpad 15.0000 mm

External Forces and Moments in WRC 107 Convention:
Design Internal Pressure Dp 3.85 kgf/cm²
Radial Load P -32220.00 N
Circumferential Shear Vc 32220.00 N
Longitudinal Shear Vl 32220.00 N
Torsional Moment Mt 15120.00 N-m
Circumferential Moment Mc 15120.00 N-m
Longitudinal Moment Ml 15120.00 N-m

Vessel material is SA 516 70 & Nozzle material is SA 106 B & design temperature is 200 degree celcius.

Please, can anyone clarify me?

Mak,

Did you make sure that your did not accidentaly check the box to say apply stress concentration factor in WRC-297.

If you still cannot find the difference between the inputs to these modules, send us your input file with same nozzle in WRC 107 and 297.

We will try to investigate it.