Dear Friends,

I am searching for some documents for a comparative study of different Flange stress/leakage analyis methods as per ASME VIII DIV1, ASME III , B31.8, EN1591 and DIN standards.

I don't know German language and also I don't have a copy of AD MERKBLATTER and DIN 2505.

I would appreciate if anyone can give me a reference of any website/technical paper/text book, where I can get a reference od AD MERKBLATTER and DIN 2505.

Also I am interested to purchase the technical paper by Waters, Rossheim et al ( 1937 ) based
on which the ASME stress equations evolved.If some has it , please let me know.


A.Bhattacharya

Stress Analyst

Bechtel Corporation

Anindya

I just joined this group and noticed that your inquiry of Sept. 3 about DIN 2505 and AD-Merkblätter and EN 1591 is still open.
I am somewhat familiar with these.

I do not know of any english translation or write up about DIN 2505 or the AD-Merkblätter.
I could scan them and send you an email but that won't do you much good if you cannot read German.
If you just have a particular question or want to do a simple comparison calculation I can help you if I know excactly what you want.
However neither DIN 2505 nor the AD-Merkblatt flange calculation addresses leakage to the best of my knowledge.
EN1591 does address flange leakage calculation however it requires very detailed information about the gasket. This gasket info is not (yet) supplied by manufacturers on on a standard basis.

I have a copy of the original Waters & Rossheim paper about the ASME flange analysis and can try to scan it in and email it to you. Where do I find your email?

Hope this is of any help, let me know if you need more details


Theo Schotten

Kindly accept my hearfelt thanks for your response.It will be extremely kind of you if you can e-mail me that paper.

My e-mail address is abhattac@bechtel.com

It will be kind of you if you clear some of these doubts:

1)AD Merkblatter ( is it the German counterpart of ASME SEC VIII ?) does it attack the leakage problem or confine it only to allowable stress as sec VIII Div 1 appendix 2 does? Or does it have anything like Flange rigidity factor like Appendix S of the same code.

2) I read a write-up on DIN 2505 where I found that the limit analysis concept is used to predict leakage. Is something like that there in AD-Merkblatter?Is DIN 2505 replaced by EN 1591?

Thanks once again for your response and the technical paper.

Best regards

Anindya Bhattacharya

Anindya

The requested paper has been emailed to you.
As to the AD-merkblatter:

1.Scope of the AD-Merkblatter
The AD-Merkblatter are approx. comparable to ASME BPVC Sect. VIII Div.1

2. Leakage
The latest version AD-2000 does not deal with leakage analysis of bolted flange connections.
For flange analysis AD-2000 refers to DIN 2505. AD-2000 also has a simplified conservative procedure, compared to DIN 2505, for flange analysis.
For leakage analysis AD-2000 refers to EN 1591.

3. DIN 2505
DIN 2505 does not have a procedure for a quantitative leakage analysis. DIN 2505 recommends the use of the joint diagram with the bolt and joint stiffnesses,deformations and loads.This will allow one to determine the requirde installation bolt preload and the remaining gasket preload when the joint is pressurized. If the preload is sufficient for the type of gasket the joint should be tight resp. not leak in an engineering sense, but one cannot determine the amount( mass or volume) of leakeage.
Leakage experts maintain that every bolted joint will leak a certain amount.
EN1591 allows the quantitive analysis of leakage.
I have not used EN1591. I have looked at it and it looks rather complicated to me.
I hope this answers your question otherwise don't hesitate to ask. These discussions are interesting
regards

Theo Schotten

Theo,

First, thanks for the paper and your response on AD-Merkblatter.

Few doubts:

1) You have mentioned that for Flange analysis AD-2000 Refers to DIN 2505.

Also you have mentioned that AD-2000 also has a simplified conservative procedure, compared to DIN 2505, for Flange analysis.

Does that mean AD Merkblatter has both options: Flange analysis as per DIN 2505 as well as by it's own method? If so which method does it recommend?

2) Is EN13445 a separate document from AD-Merkblatter ?

For EN1591 and it's comparison to Taylor Forge method, you can see ( in case you already have not seen) a good paper by Yann Guérout
in www.sealeng.com.

Anindya Bhattacharya

Anindya

Question 1:AD-Merkblatt has no recommendation as to what to use: The DIN 2505 analysis is more involved. The simplified AD-design formulas will most of the time result in a thicker flange.
Question 2:EN 13445 is different from AD-Merkblatter

Hi Anindya,

You can purchase AD-2000 complete version or individual sections in English from BEUTH, Germany. For more information, go to:
http://www.beuth.de