TSSA requirements for CRN

[mudd8]

I have a client that is trying to obtain CRN's for two (2) vessels that are storing anhydrous ammonia. These vessels were fabricated in 1956. The TSSA is asking for stamped design drawings and calculations showing that they are in accordance with the original design code in 1956. They are also asking that the MDMT calculation is based on current code requirements.

I have the original Manufacturer's Data Report that states that they were built to 1952 ASME Code Section VIII. I have attempted to contact the original manufacturer (Flint Steel Corp, Memphis, TN) but they no longer exist and their documentation no longer exists.

I think right now I am looking at preparing a new set of drawings and doing my own calculations. My questions are:

1. Does anyone know where I can obtain a copy of ASME Section VIII - 1952?

2. Does anyone know where I can obtain a copy of CSA B51 - 1955?

3. I am a structural engineer who doesn't normally get involved in pressure vessels. Can anyone give me some head's up information that I should be watching out for?

Any help is appreciated.

 

[SnTMan]

You might want to hire this out. It's gonna get messy...

Regards,

Mike

 

[Guest102023]

Agree with SnTMan, this needs to be handled by an experienced Code person. Without the original design package in hand it will be complicated.

 

[Tomtation]

Try the libraries.

 

[fegenbush]

I will disagree with SnTMan. Having looked at the code of the era, it is dead simple. I do know where *a* copy exists, but I do not know if they would be willing to sell it. If you would like, I can ask.

 

[mudd8]

@fegenbush I am interested. As it looks right now I may have to drive to Wayne State University library to access this code. I am about 50 miles from there and it is not a big deal, but I would rather have a copy for full use.

 

[SnTMan]

fegenbush, with all due resperct, it ain't over till its' over...

Regards,

Mike

 

[fegenbush]

Mike, I meant no disrespect. Were it a current code, I would feel differently, but the older codes with references to testing the welds with "a sharp, striking blow" of a 2lb hammer while the vessel is under pressure aren't terribly high brow.

My comment was made more in confidence of mudd8's abilities than to the simplicity of the code.

/Also, he is not going to get much past the TSSA. They are thorough if anything.

 

[SnTMan]

fegenbush, didn't think that you did

Agreed that original C of C is simple, but as you say "he is not going to get much past the TSSA. They are thorough if anything."

Putting together enough reliable info to satisfy TSSA? Who knows.

Wishing all the luck in the world...

Regards,

Mike

 

[Tubalcain]

Sounds like the vessels pre-date requirement to have CRN's. Are CRN's being asked for to allow for repairs/alteration?

Maybe scrap trying to use '50's code and take vessel as-is and have Engineering Vessel company provide calc.'s to allow vessel to be given CRN. However, I would doubt that the metal used in 50's meets fully-killed and fine-grain practise for NH3 service.

 

[mudd8]

Just an update:

1. I got a copy of the old code.

2. I retained the services of a mechie to help me with it.

3. The vessels meet the old code.

4. MDMT worked out to 32degF for the heads and 40degF for the shell. This is not going to fly in Ontario, Canada. Right now we are trying to talk to the TSSA to determine what the next steps are.

My personal take on this is that the TSSA does not want tanks made out of this particular material in Ontario. They have stated that the get "grandfathered in" as long as they meet the original code, but that the MDMT calculation is also required to current code, knowing full well that this material is not going to pass. It is a "political" way of telling my client that his tanks need to be decommissioned.