Dear Richard/Dave,

Could anyone please tell me what the differences between PD 5500 Annex G and WRC 107/297 Stress Calculation Method are?

I studied from some documents; it states that PD 5500 calculates stresses in vessel side. If we are calculating stresses in vessel side by WRC 107, again by using PD 5500 is required? If required why and what is the differences.

I searched in this Forum about this concept. But I didn’t get the complete information or guidance for knowing this concept.

Can you please clarify?

Dear Richard/Dave,

Could anyone please tell me what the differences between PD 5500 Annex G and WRC 107/297 Stress Calculation Method are?

I studied from some documents; it states that PD 5500 calculates stresses in vessel side. If we are calculating stresses in vessel side by WRC 107, again by using PD 5500 is required? If required why and what is the differences.

I searched in this Forum about this concept. But I didn’t get the complete information or guidance for knowing this concept.

Can you please clarify?

can anyone please clarify these doubts

From what I understand that PD5500 and WRC 107 are comparable. But, PD5500 applies a stress concentration factor for pressure stress. Imho it is conservative as an SCF would imply a fatigue evaluation. The alllowables are also different.

In addition to Mandeep's comments ...

WRC297 is a publication subsequent to WRC107, that also includes nozzle flexibility calculations. WRC297 was intended to be a refinement of WRC107, but recent research casts doubts on accuracy of the WRC297 stress calculations. WRC297 while only calculating nozzle to nozzle intersections also computes the stress in the nozzle wall which WRC107 does not

PD5500 Annex G is a British/European standard similar to WRC107, but it includes the evaluation of nozzles on heads (where the WRC documents only address cylinder-cylinder) junctions.

Thanks for your Valuable information Mr. Mandeep singh & Richard,
In our project, after qualifying the nozzle in both WRC 107 & 297 also client require to do PD5500 check.

A. They mention the following statements.

WRC 107 checks only for Vessel side.
WRC 297 check for both NOZZLE & VESSEL side
PD5500 is used to check the compressive buckling check.
In WRC, this type of (compressive buckling check) stress check is not there?

B. As you said. “PD5500 ANNEX G is similar to WRC 107”. So PD5500 also calculating stress on vessel side only?

C. As you said, “WRC 297 while only is calculating NOZZLE TO NOZZLE intersections.” It Means: used only for cylindered type nozzles not for spherical nozzle.

D. As you said”, PD5500 applies a SCF for pressure stresses”

I think PD/2eas is the formulae for Fp (Pressure-hoop stress) and that value is adding to membrane stress (sub total). I didn’t find that SCF multification factor in my hand calculations. whether in my case SCF=1? & I didn’t find any input for pressure SCF in CAESAR-II PD5500 module? Can you please provide reference. It helps in my future works.

Please correct me if I am wrong.
Thanks In advance.

Mr. Richard,
Please clarify my doubts.