Hello everybody, I have a question that keeps me busy for a while. I hope there are people here that can give me some advice / experiences for this matter in how to handle with this.
I'm a piping (stress) engineer from The Netherlands and for most clients we use the design code EN-13480 for the calculation and fabrication of piping systems.
Currently I'm working on a project with piping diameters up to and including DN900 (36"). The system is calculated according to the EN-13480.
Due to the delivery time and/or costs of some large bore fittings (in this example DN900 equal Tee type B1) we are currently looking for alternative ASME fittings. I know it's possible to use ASME fittings in Europe, as long as we make a Particular Material Appraisal for this component and make a strength calculation.
And here is where the problems comes. How to calculate an ASME fitting as the wall thicknesses are not defined in the ASME B16.9?
When using an ASME design code like the B31.1 or 31.3, this is no problem, because the B16.9 says that the fittings of a certain schedule are at least just as strong as the corresponding pipe. So a 36" pipe with schedule XS can handle the same pressure as a 36" equal tee schedule XS. The fabricator probably knows how thick the tee needs to be in order to comply to the B16.9.
But this will not work when using a B16.9 fitting in combination with the EN-13480. Because this code says you need to calculate it to verify that it will be strong enough.
How is it possible to calculate it without having the wall thickness? And it's not possible to get a measurement report, because the tee will only be fabricated after ordering.
So in my example the supplier offers a B16.9 A234WPB / P265GH 36" tee schedule XS. According to the B16.9 this tee should be at least as strong as a P265GH 36" pipe schedule XS.
Now I calculated that a P265GH 36" pipe schedule XS can handle 32 bar(g). That means that the corresponding tee should also be able to handle 32 bar(g), according to the B16.9. The fabricator needs to make sure the tee will be fabricated accordingly.
But within the EN-13480 I stilll need to verify this with a calculation. Is it possible to make a calculation before the tee is actually fabricated?
My system is only 19 bar(g) so based on the B16.9 this tee should be strong enough. But I just can't verify it with a calculation as required for the EN-13480. Kinda frustrating.....
It's a long story, sorry for that. Maybe someone can tell me their experiences with a similiar case?
I'm a piping (stress) engineer from The Netherlands and for most clients we use the design code EN-13480 for the calculation and fabrication of piping systems.
Currently I'm working on a project with piping diameters up to and including DN900 (36"). The system is calculated according to the EN-13480.
Due to the delivery time and/or costs of some large bore fittings (in this example DN900 equal Tee type B1) we are currently looking for alternative ASME fittings. I know it's possible to use ASME fittings in Europe, as long as we make a Particular Material Appraisal for this component and make a strength calculation.
And here is where the problems comes. How to calculate an ASME fitting as the wall thicknesses are not defined in the ASME B16.9?
When using an ASME design code like the B31.1 or 31.3, this is no problem, because the B16.9 says that the fittings of a certain schedule are at least just as strong as the corresponding pipe. So a 36" pipe with schedule XS can handle the same pressure as a 36" equal tee schedule XS. The fabricator probably knows how thick the tee needs to be in order to comply to the B16.9.
But this will not work when using a B16.9 fitting in combination with the EN-13480. Because this code says you need to calculate it to verify that it will be strong enough.
How is it possible to calculate it without having the wall thickness? And it's not possible to get a measurement report, because the tee will only be fabricated after ordering.
So in my example the supplier offers a B16.9 A234WPB / P265GH 36" tee schedule XS. According to the B16.9 this tee should be at least as strong as a P265GH 36" pipe schedule XS.
Now I calculated that a P265GH 36" pipe schedule XS can handle 32 bar(g). That means that the corresponding tee should also be able to handle 32 bar(g), according to the B16.9. The fabricator needs to make sure the tee will be fabricated accordingly.
But within the EN-13480 I stilll need to verify this with a calculation. Is it possible to make a calculation before the tee is actually fabricated?
My system is only 19 bar(g) so based on the B16.9 this tee should be strong enough. But I just can't verify it with a calculation as required for the EN-13480. Kinda frustrating.....
It's a long story, sorry for that. Maybe someone can tell me their experiences with a similiar case?
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