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Obtaining older versions of the ASME code 3

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rmillercwi

Materials
Jul 19, 2006
76
My company has been detained to assist with the re-rating of an older (20 years) boiler. Small HRSG attached to an LM 5000. We are going to be increasing the mawp from 620 to over 1100. The engineers have weeded out what can stay and what gets replaced.

Now we are in the process of confirming the works that is staying is acceptable for use in comparison to the new code. Presumably they want to review the design calculations methods, past nde requirements, weld sizes etc . I might not be exactly right with what they are doing but have asked to dig into this.

To do this we need to review the original code of construction from 20 years ago. Where does somebody get this?

As always, your thoughts and opinions are greatly appreciated.
 
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rmillercwi;
You cannot pick and choose what edition of the ASME B&PV Code you are going to use for material and NDT requirements for an alteration. By definition, this is an alteration and is under the requirements of the National Board Inspection Code (NBIC), NB-23. You need to review re-rating requirements and follow them. Original code of construction does not refer to the original addendum and edition; it simply refers back to the code of construction.

If you need to obtain a copy of the code from 20 years ago for reference purposes, I would suggest you contact the National Board of Boiler and Pressure Vessel Inspectors. For a nominal fee they can obtain a copy of the applicable code section for you. Have you contacted the Jurisdiction where the HRSG is installed for help in the alteration process?
 
I've used the Linda Hall Library to obtain very old ASME Code Editions and Addenda.
 
I disagree with metengr. The allowable stresses, etc. from the original code (and edition) must be followed.

Check your local library. You could do a regional search at There would also be some online (paid) resources available such as Linda Hall, IHS, etc.

I2I
 
insult2injury;
Why? What is your basis for disagreement? Do you realize that allowable stresses are changed over time and in some cases are reduced for the same material because of new data or operating experience? Do you know the impact of this change? Read the NIBC for alteration rules.

Don't confuse original code with original edition and addendum. Why? Because there is an inquiry on this very question in the NBIC.
 
Somehow I have a problem about rerating a boiler from 620 psig to 1100 psig unless the boiler was originally designed for 1100 psig.
Do you have the original manufacturers data on this boiler and if so what is the original MAWP?
The cost to upgrade such boiler would seem to me prohibitive and probably it would be less expansive and safer to buy a new boiler.
 
metengr,
In your experience, (excluding the allowable stresses) do you see the current edition of the Code being used for repairs and alterations... as opposied to the original year and addenda?

Joe Tank
 
JoeTank;
For weld repairs, the edition and addendum of the NBIC that is accepted by the Jurisdiction is required. In other words, the local Jurisdiction may require the 2004 edition/2006 addendum of the NBIC. As a NB Certificate holder, if I perform weld repairs to my boiler, I must follow the 2004/2006 NBIC if the object is located in this Jurisdiction.

The NBIC normally defaults back to the Code of Construction. In this case for weld repairs, we will follow the latest edition of ASME B&PV Code.

I use this same approach for alterations. The only time I would refer back to an earlier edition of ASME B&PV Code is to obtain information regarding specific materials that have been discontinued. If the material is currently listed in Section II, I will use current information, NDT, and preheat and PWHT requirements.
 
metengr: The opposite is also true. Allowables may be increased over time. Can you use the higher allowables that are a result of more stringent specifications? I think not.

I2I
 
I2I;
Yes, you can. Please read the 2004 Edition/2006 Addendum of the NBIC, specifically RD-3010 for Re-Rating vessels. Yes, one can use a later edition/addendum of the original code containing higher allowable stresses for applicable material. The rules are all there in RD-3010 for re-rating a vessel based on satisfying conditions a) through i). I am not going to repeat these here.
 
I'll have to go with metengr on this call. We will use the lowest of the allowables on any material in the original code or the latest edition of the code as the higher values might be based on improved analysis or manufacturing techniques which weren't available in the original construction. If the original code has a lower allowable than the latest code we go with that value and conversely if the latest version had the lower value we go with that value. We have never use a higher allowable value than the original construction code.
In the details we went with the most conservative approach to design. This is done with the full concurrence of our AI. We put this approach to the full test when integral nozzles became readily available and when we made repairs on vessels in very highly cyclic service.
 
^ This is exactly our perception and intent of ultimatly using the most conservative level of acceptance possible when evaluating the use of existing materials. This in conjunction with an FAC study, lots of UT thickness checking, various NDE, hydrotesting, etc.

Other interest in reviewing the old code is to review the various other requirements such as pwht, nde, etc. As an example, perhaps 20 years ago carbon steel may have been PWHT'd at say a 1000 degrees in lieu of 1100 or maybe the material didnt require stress at all back then (probably not, but we dont know that) or the soak time may have changed. RT requirements for specific diameters may have been less stringent in the past. Who knows what we will find when we compare. Any significant differences will have to be evaluated regardless of acceptance by stress calculations. A recent example of this is the 2004 change of stress temp for P4 materials. In cases like this, further evaluation would have to be peformed.

I understand the local jurisdiction having authority of defining the applicible code and it makes perfect sense. Does it ever not use the latest version for NBIC repairs? Why would you not use the latest edition?

The explaination of "original code of construction" was particularly helpful. I had always assumed this meant the year of addendum and thought this was wrong going back in time but up to now was never an issue. If I understand the content in above postings correctly, it is reffering only to the code entity such as ASME and in no way is implying exactly which particular historic addendum.
 
I understand the local jurisdiction having authority of defining the applicible code and it makes perfect sense. Does it ever not use the latest version for NBIC repairs? Why would you not use the latest edition?

Jurisdictions across the US adopt various editions of the NBIC. My suggestion is to go to the National Board web site and locate the Jurisdiction of interest to determine what edition/addendum of the NBIC has been adopted and their boiler/pressure vessel rules.

Adoption of Codes and Standards in a Jurisdiction is a lengthy process because local government is involved. Once adopted, updating the Codes and Standards can be a lengthy process as well.
 

The actual words used in the NBIC state the following:

........repairs and alterations to pressure retaining items shall conform, insofar as possible, to the section and edition of the ASME Code most applicable to the work planned.............

NOTE:The 2007 Edition added words to address ASME RTP-1, (fiberglass vessels)

With that said, these words have existed in the NBIC as far back as the 1998 Edition.
Consult with your AI, and make sure the AI is competent (certificate of competency) within the jurisdiction where the work is planned.

 
It is unlikely to find a boiler or vessel constructed to 1100psi and stamped to 600psi, but a quick calculation of drums and tubes will give an idea if the item can be re-rated or not, and if the first passed; then you proceed to the Code and standards to re-rate it.
 
rmillercwi-

In addition to the typically sage advice metengr has provided already, you might want to take a look at NBIC interpretation 98-14, which I presume to be the predecessor to RD-3010. In particular...
Question 4: May a pressure retaining item be re-rated using a later edition/addenda of the original code of construction which permits higher allowable stress values for the material than was used in the original construction?

Reply 4: Yes, in compliance with the following minimum criteria: .....

As always, keep in mind that the advice you get on a free internet forum is worth every penny you paid for it! Get opinions here, but make your decisions based on your own research.


I2I-

In addition to 98-14, take a look at Interpretation 95-19


NBIC Interpretations available at:
jt
 
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