ASME vs EN 13445| EN 12953 | Allowable stress for EN materials in ASME Sec II part D (Metric)

[shiraz883]

Hi,

I am designing a pressure vessel (waste heat boiler) with EN code - EN12953 and flexible tubesheet design to be verified by FEA using EN code 13445.

Few questions:

1. For design by rule - for shell thickness - I am using PVelite but it has built in EN13445 code not EN12953. Is there a difference in formulae for calculating the shell thickness between these two code numbers quoted?

2. For the FEA, is the methodology from ASME same as EN 13445 code? Can I follow the ASME code (Sec VIII Div.2 part 5) for the method of analysis - i.e. satisfying plastic collapse, local failure, thermal ratcheting and collapse from buckling while taking the stress allowable from EN code?
I also see that some of the EN materials are mentioned in ASME Sec II part D - may be introduced in 2021 - and wondering whether the allowable from the ASME Sec II part D for these EN materials can be used instead of searching through EN code because may be ASME has already done that for the analyst?



Shiraz
Sr. Engineer

 

[XL83NL]

Is there a difference in formulae for calculating the shell thickness between these two code numbers quoted?

That's something you, as a designer, should look up and find out yourself. The shell is a critical part of the overall design. Basing that design on something someone said on a forum, who you don't know, is not a good idea.

Huub
- You never get what you expect, you only get what you inspect.

 

[shiraz883]

Yes that's right, I intend to do that but just wanted some inputs if someone has already gone that path then it gives some kind of information where to look and what to expect.
Neverthless, I found out about the codes and the thickness comes to be same for both the codes EN13445 vs EN12953 for the shell thickness.

Any info on the methodology in EN code for design by analysis? or whatever I have written as per my understanding of the ASME code and allowable stress by EN code will suffice that the vessel is designed by EN code?

By the way who said/wrote anything about basing the design based on the information here?

Shiraz
Sr. Engineer

 

[XL83NL]

Here are some leads regarding q2;

https://unm.fr/wp-content/uploads/2022/10/EN13445_ASME_comparaison.pdf

https://www.sciencedirect.com/science/article/abs/pii/S0308016104001073

https://www.linkedin.com/feed/update/urn:li:activity:7203412313180131329/

(or see attached pdf below if the link doesn't work)




Huub
- You never get what you expect, you only get what you inspect.