ANSWERS to kl_m_a query PWHT for welded joints in Amine services

From: <Al>
Date: Tue Feb 17 2004 - 19:55:00 EST


Hear hear. to Gords comments. They apply to so much of what is expressed on this site.
I was such a Metallurgist for several NDT/consulting Firms for many years . But no offence taken Gord
because i totally agree with what you are saying. Why would you try to "Convince" the client not to do it when you have no knowledge of the reasons it is
required or might be required. Do you have ALL the facts that led to such decisions.....

But I wouldnt trust anybodys opinion off the net, or off the cuff, including anything Al says (my own comments, because i dont have all the facts) and so often the people writing here (and the client) dont even have all the facts themselves. just trying to give you their best guess...hence the flange failure guessing game (tag team threads).

I often say that answers off the internet are worth what you pay for them... pretty close to nothing.
They are pointers , maybe clues and background.

There is no substitute for Hiring the right expertise .. the person with the right credentials will ask the right questions. Then you maybe have a shooting chance of getting close to the right answer. What was that Chris says about hitting an elephant???? Seems to be right on the money.

al

PS. Disclaimer ; However if you hired that al guy, then maybe I'd trust his opinion. hehe :)

-----Original Message-----
From: <a href="/group/PipingDesign/post?postID=14fCO8OaJ7CdLnCJDOM62wyIk1joiwlxKzQgUKdrLyOjNgfFKTLDZmdXXiBs3r1lIouxeP36PSX7ePb5i_z_iQ">Gordon.Reddek@Alcan.com</a> [mailto:<a href="/group/PipingDesign/post?postID=14fCO8OaJ7CdLnCJDOM62wyIk1joiwlxKzQgUKdrLyOjNgfFKTLDZmdXXiBs3r1lIouxeP36PSX7ePb5i_z_iQ">Gordon.Reddek@Alcan.com</a>] Sent: Tuesday, February 17, 2004 3:54 PM To: <a href="/group/PipingDesign/post?postID=QQq6u_7oz1s1pCuoqNBSvJFp_Uh851BdMXuVj6PSUtgv08uQzgB3PVQpelsqQYRyMuE9AQoO0d0N31PbU4XMHAfQ">PipingDesign@yahoogroups.com</a> Subject: Re: [PipingDesign] PWHT for wled joints in Amine services

k1_m_a,

This is a serious issue and you should be very careful with your decision.   I will confirm Al's remark that PWHT is not something done to a selection of welds. If it is required it is done to ALL welds. I also understand the concern of the client. If Amine service causes failures that can be solved by PWHT then I would also want it done if I were them. I believe you are talking to the wrong people. A metallurgist (or materials science person) makes the decision on whether welds need post weld heat treated in a particular service, in this case Amine service. I think you will find that the people in this group are pipe designers who design the piping system. Pipe designers very seldom have the qualifications required to make the very important metallurgical decisions about materials of construction required for complex chemical service. I strongly advise you to look around for a metallurgist or materials expert in your organisation, or in an organisation you can trust, to help you with this one. I personally would not take advice on an important issue like this from people I do not know on the internet. Over the years I have learned that when it comes to serious issues it is important to take advice from people you absolutely know to be experts in the field you require advice in. I have seen many failures resulting from advice taken from people who are amateurs who think they understand an issue but in fact do not have a deep down understanding of the real issues at stake. Please seek the advise of a qualified and practising metallurgist or materials expert. If you do not have one in house, or you do not have access to an organisation that has one I suggest you contact companies that specialise in non destructive testing (NDT). They normally have qualified metallurgists on their staff. Also, be prepared to pay for the advice. This is important because if the advice given you is wrong you will have recourse to legal action. If you take advice from an amateur on the web and the advice turns out to be wrong, you will be left holding the candle.

"k1_m_a" <k1_m_a@yahoo.com> 17/02/2004 11:02 PM
Please respond to PipingDesign

         To:     <a href="/group/PipingDesign/post?postID=QQq6u_7oz1s1pCuoqNBSvJFp_Uh851BdMXuVj6PSUtgv08uQzgB3PVQpelsqQYRyMuE9AQoO0d0N31PbU4XMHAfQ">PipingDesign@yahoogroups.com</a>
         cc:
         Subject:        [PipingDesign] PWHT for wled joints in Amine
services

Hi,

Can anybody help me making a good decision regarding the necessity of PWHT for weld jionts in Amine services?

We are in construction part of a Gas Sweetening EPC project containing three type of Amine services. A (Amine), AL ( Lean Amine) and AR (Rich Amine).
Based on the criteria defined by the Amine plant designer engineer, we have done PWHT only for weld jionts in AR ( Amine Rich) lines. But now, we are under pressure by the Client that in any Amine service including A, AL and AR all the weld jionts shall be Post Weld Heat Treated.

Your kind answer based on your engineering practices, helping me to convince the Client that PWHT is not needed for A and AL services (or can be done only for some limited number of welds) is most appreciated.

I will be glad to give any more necessary information if needed, e.g. Gas composition, etc.

Thanking you,

Keivan Mashayekh



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Main site: <a href="http://www.pipingdesign.com">http://www.pipingdesign.com</a> <a href="http://www.pipingdesign.org">http://www.pipingdesign.org</a> <a href="http://www.pipingdesign.ca">http://www.pipingdesign.ca</a> Yahoo! Groups Links Received on Tue Feb 17 19:55:00 2004

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