NBIC Rules on Pressure test

[tc7]

On a repair of a vessel originally constructed IAW Sect VIII and used for steam upto 1000 psi at sat. temps, which has been in service for several years, I have been told that NBIC rules will be applicable. What is the prevailing philosophy on hydro testing if 360 deg RT inspections have been performed and the nature of the "repair" may really be an alteration whereby we will remove and cap off a header just down stream of a vessel nozzle. There will be no valves between the new cap and vessel.

Is this in fact an alteration rather than a repair?
And will a 1.5x hydro be required when RT is accomplished?

Ultimately I understand we have to satisfy the AI but I want to be informed about the rules before I speak with them and I do not at present have a copy of NBIC.

Thanks for opinions and thoughts.

 

[metengr]

tc7;
Hydrotesting or pressure testing is not necessarily required for repairs or alterations under the current rules (2004 Edition/2006 Addendum or later) of the NBIC. NDE is one option in lieu of pressure testing regarding all repairs. For alterations, it depends on the type of alteration. In certain cases, NDE versus a hydrotest is appropriate. In other cases of alteration, where NDE is not performed or no physical work is performed, a hydrotest will be necessary to assure adequacy of the new design (re-rating) conditions.

In your example, if you remove a header and cap the line from the nozzle I don't see how this is an alteration using the current rules of the NBIC. Although, I would need to review in detail your proposed scope of work, and what impact this change has on the pressure retaining capability of the item (this is key for an alteration).
You absolutely need to review the NBIC and applicable le parts before you discuss this with the AI.

 

[API123]

I would prepare for hydrotesting, but due to the changes in Sec. VIII it may be 1.5 or 1.3 times the MAWP depending on the year of construction.

The philosophy of hydro regardless on NDE is it "stresses the weld". No form of NDE provides that for you.

Ultimately it is the inspectors choice.

 

[JoeTank]

You need a copy of the applicable NBIC. Don't rely upon only the opinion of the AI. Nor should you rely upon only the info obtained from this forum. Go to the source of informantion... the NBIC Code.

Joe Tank

 

[tc7]

Joe-
I agree with you that I need a copy of the applicable book but ahead of that, I am simply looking for ideas, opinions and experience that, fortunately, some folks on this Forum are willing to share.
I don't agree that I shouldn't rely upon the opinion of the AI. They don't become "authorized" without proving their knowledge, skills and abilities. That said, I do need to be in a position to discuss and communicate and not reduce to futile debate.

 

[metengr]

tc7;
I am of the opinion with a 99% success rate that if you are well prepared prior to meeting with the AI, you will be able to move forward with your proposed scope of work (alteration or repair).

With that said, I would detail the scope and sequence of work. Once this is completed, go back and review the NBIC (using the specific Edition and addendum that is required by the local Jurisdiction). If you are not re-rating the vessel per the NBIC requirements for alteration, then you have a change in the item's configuration, which is also an alteration. In this case, I would argue the NDE can be performed of sufficient magnitude to assure the alteration performed using welding (physical work) is adequate.

 

[JoeTank]

tc7,
I probably came across a bit crude and coarse in my last email I did not mean to sound that way. My apologies. Like you, I too try to get my ducks in a row before I have to deal with an issue. Regarding afvice from an AI, I do not consider then as all-knowing or all-seeing folks. I have received numerous statements form AI's that show me that they are not all created equally. My advice is to trust them, but verify their information. Check the Code and NBIC in order verify whether they are stating Code/NBIC facts or AI opinions.

Joe Tank

 

[BJaffa]

I think Tc7 may mis-understand the role of the A-I. We contract the service of a large firm that provides us with A-I's. These professionals are trained to interpret the NBIC and provide a review inspector for documents prepared by the Code shop performing the work. The A-I does not design the work but in fact only authorizes the Code shop to proceed with the work. All design and inspection criteria should be specified by the Code shop. The A-I reviews and accepts the job plan and establishes inspection points. Inspections are a Code specified issue and not at the sole discretion of the A-I.
Tc7 should determine the required inspections and present them to the A-I for Authorization, not the other way around.

Tc7 description sounds to me like a non-routine repair not an alteration.

Current philosophy seems to be for "meaningful" testing. RT, UT, Hydro selection should be based on specific geometry of the work.

 

[API123]

I have enjoyed this thread and all the reply's are very accurate. Make sure you are very familiar with all the applicable standards and regulations as well as client procedures (etc.) As far as the prevailing philosophy of hydro vs NDE, hope that helped.

As far as AI's are concerned, we always attempt to provide the correct testing based on the specific details of the job. Sorry for being generic, but never commit to anything until I've reviewed 100% of the job details (been at it to long). Also if you know the AI from previous work your job should be very easy since they tend to be very consistent.

 

[metengr]

Just a point of clarification, there is no AI role in the NBIC. The Inspector is what is stated in the NBIC and that refers to a National Board commissioned Inspector. The AI is used for new construction activities.

 

[vesselfab]

METENG

I don't know about where you are, but here, most, if not all plants have an AI for their programs. All AIs are NBIC commisioned, aren't they?

Most people use the terms interchangably.

Now i realize that not all repairs are in plants...but....most are. especially 1000 psi saturated steam.

 

[CodeRef]

FYI
metengr is technically correct, and vesselfab is generally correct.
Jurisdictions commonly use the term Commissioned Inspector or CI when relating to work conducted within the scope of the NBIC.

Everything below is taken from NB-263, Rules for Commissioned Inspectors {October 2007}

Inspector – A National Board Commissioned Inspector or a National Board Commissioned Owner-User Inspector.
Authorized Inspector – An individual holding a valid National Board commission with the appropriate endorsement and designated as such by an Authorized Inspection Agency.
National Board Commissioned Inspector – An individual who holds a valid National Board Commission and who is regularly employed as an inspector by an Authorized Inspection Agency. A National Board Commissioned Inspector may perform inservice inspections and inspections associated with authorization, in process and acceptance of repairs and alterations as defined in the NBIC.
National Board Commissioned Inspector Employed by an Owner-User – An individual who holds a valid National Board Commission and who is regularly employed as an inspector by an Owner-User Inspection Organization.

.....Many jurisdictions require individuals who have been issued a National Board Commission to meet additional requirements prior to performing inspection activities in that jurisdiction. Because the requirements may vary among the jurisdictions, Commissioned Inspectors and their employers must understand and abide by the specific requirements of the jurisdiction in which they practice....