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 = 3.0000 mm
Shell Diameter = 4000.000 mm
Shell Thickness = 15.0000 mm
Shell Stress Concentration Factor = 1.000

Diameter Basis for Nozzle = ID
Corrosion Allowance for Nozzle = 3.0000 mm
Nozzle Diameter = 242.926 mm
Nozzle Thickness = 15.0622 mm
Nozzle Stress Concentration Factor = 1.000

Diameter of Reinforcing Pad = 496.000 mm
Thickness of Reinforcing Pad = 15.0000 mm

External Forces and Moments in WRC 107 Convention:
Design Internal Pressure 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?

_________________
Makrand Pandurang Sakpal,
Static Equipment Design,
makrands9@gmail.com,
Ph no:- 9967949656.

Can anyone please reply on this issue?

_________________
Makrand Pandurang Sakpal,
Static Equipment Design,
makrands9@gmail.com,
Ph no:- 9967949656.

Dear Makrand
pl. note following point.
1. WRC 107 is prepared based of bijlaard's work.
2. WRC 297 is extension of WRC 107, covering more number of geometric parameter.
3. ASME SEC VIII Div-1 doesn't say anything regarding applicability of either WRC 107 or 297.
4. However, Div-2 says to use WRC 107 for Nozzle to shell/D'end junction & WRC 297 for Nozzle to Shell junction only
5. However, many EPC prefer's to use WRC 297 for Nozzle to Shell junction & WRC 107 for Nozzle to D'end junction

6. WRC 107 & WRC 297 is compared with FEA Results , it has been found that WRC 107 undere predict the membrane stress, hence higher piping local is achieved. However, WRC- 297 over- prediact the membrane stree, hence lower piping load is achieved.

Thanking you
Vishal Tailor