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Is stamping heat numbers onto pipe the pipefitters responsibility? 5

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shamino

Mechanical
Jan 21, 2012
18
Hi, I am a newly graduated QCI at a vessel shop that has a struggling QC department. There are a lot of things we are doing wrong and we get dinged for it every time the AI comes in. I want to stop this, which brings me to my question.

On the last AI visit, my colleague responsible for vessels realized he had not recorded the heat number on the steam coil (10 minutes prior to the AI's visit.) So I crawled into this vessel and there was no heat number stamped on. Because of this (and about 8 other reasons), the vessel was not signed off and we got an NCR.

Even though I am not the vessel guy (I take care of piping, and steam coil falls under vessel parts), I want to make sure this never happens again. I want to know who is responsible for stamping heat numbers onto pipe and why were they not stamped on? And furthermore, why did we not record them on our weld mapping drawings? The reason I ask is because often the fitters will simply write the Heat # on with a paint marker, which is wrong - they should all be stamped. For our flowline I had asked a labourer to do the stamping, but if this is the job of the fitters, then do you think this is something I should talk to them about?


 
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Wouldn't this kind of stuff be covered under your QC plan?
 
Yes it is in the manual, but it just says that it falls under QC's responsibility to ensure that this is done. So there you have it ladies and gents, when in doubt look in the manual. I know this probably sounds like a very basic and stupid question, but I have to break this down into an idiot proof method so that we make sure that something this retarded never happens again.

Here is my thoughts. What I am going to do is, whenever the piping and coils have been welded and are ready for ht, i'm going to inspect them and make sure the fitters have stamped the heat number in an easily identifiable area. That's all that really needs to be done, and I don't know why it wasn't done in the very beginning. Whoever was working in QC then didn't do their job which I guess is why they're not there anymore.

On that note I just realized that I posted this in the wrong forum. I posted this in ASME because we're a section 8 div 1 shop, but I should have posted this in the qc forum.
 
Heat number on pipe is normally "painted" on with computer coding letters down the outside (it isn't inscribed in by engraving.) So, how would you expect to retain such a painted on piece of information when it is rolled, ground, twisted, and fabricated out of existence?

Are you sure your QA plan is based on the legal requirements and is not adding on extra bells and whistles?

How do you track and retain the plate id's and plate "metallurgy" data when you roll plates and weld them up into a vessel? Your "pipes" data for a coil, your nozzles data, and your weld filler data should be treated the same way.
 
We don't fabricate the pipe itself though, the pipe comes to us already fabricated. It DOES come with an MTR with a heat # on it. When the pipe fitters are cutting up and assembling spooling, I would assume they should be transferring that # onto all the parts they use, otherwise how do we know what we're using?

Are we making more work for ourselves? That's a good question and I don't know. If so it is the last thing we need to be doing, but that is why I am just throwing this out there, see what other people do. We deal with ABSA and from what i've heard they have enforce the strictest regulations regarding vessels in north america. What I was told by my former QA manager is that a heat number must be on every piece of pipe connecting to a vessel because if there is every a problem, say god forbid a failure, then the inspectors can go back and trace the part to a heat batch. We also have to stamp welder id's for the same reason - traceability.
 
"We don't fabricate the pipe itself though, the pipe comes to us already fabricated. It DOES come with an MTR with a heat # on it. When the pipe fitters are cutting up and assembling spooling, I would assume they should be transferring that # onto all the parts they use, otherwise how do we know what we're using? "

Assume? nope! like you wrote, when the pipe enters the yard, it needs to have identifying information (i.e. MTR, Heat #, PO, etc.) on it. if not, reject it. You certainly do not want to write that information on the pipe yourself, now do you? Imagine yourself sitting on the witness stand . . . so, how do you know that pipe is x-y-z?

when a section of pipe is removed from the joint already with pipe id data on it, the same pipe id data is to be written with a white paint marker on section of pipe removed from the joint. whom cuts the pipe, writes the same information on cut pipe. have someone QA the work.

how about using the isometric drawings or otherwise to id the welds? then those dwgs or otherwise are part of records.

hope this helps.
good luck!
-pmover
 
As the QCI you are responsible for ensuring material traceability to the supporting documentation is maintained throughout fabrication. It doesn't mean you do the actual marking of materials. Normally it is the task of the pipefitters or boilermakers to transfer the ID numbers from the identified pieces to the pieces to be removed, prior to making the cut. It would be your responsibility to do enough inspections, audits, reviews, etc. to ensure this is done.

As mentioned previously, it would be a good idea to record actual welder, NDE and material information on construction QC drawings and keep these as part of your QC Turnover Packages.

You should be doing your own inspections continuously and prior to the Authorized Inspector arriving on site ensuring there are no deficiencies.
 
Typically, QA is responsible for making sure incoming goods have markings, and for checking component documentation. Parts are traced, until either (1) part is covered entirely by other parts, or (2) marking is grit blasted for subsequent coating. Re-marking (eg on offcuts) are typically done by person doing the cutting.

If failure occurs, the vessel MDR will be retrieved and reviewed. If required, physical chemical analysis of the failed component can be conducted to confirm its chemistry matches its material certificate chemistry. IMO stamping of every component is over the top.
 
I want to thank everyone for their responses, its really helpful and gives me some things to ponder over. As some of you suggested, I have been tracking welder ID's and NDE reports on the construction drawings (weld mapping), although this was not being done properly prior to me joining the QC department. Today when I go into work I will have a talk with my team about stamping and what we can do to not get dinged by the AI again.

Its going to take a bit of work but we're going to get a really good program running here soon.

Cheers!
 
I keep on thinking about the rejected vessel.
Perhaps can ask AI consideration to accept PAMI result instead.

p/s: luckily the AI didn't make report to ASME. Worst case, the u-stamp license can be revoked.
 
isnt it a bad practice to punch something on a pipe??? i believe it will reduce the thickness of the pipe. that is just my thought.
 
noorazran79: that is a bit of an overeaction. in fact i was mistaken, he never issued us an NCR (nonconformance report), but he could have. we have been getting a string of these lately. the point of an NCR isn't the shut down a company, and that's rarely what happens. the point of an NCR is to identify what things you are missing before the vessel can be signed off. and for us, its to help us get our feet back on the ground. after we get an NCR we have a list of steps to take to resolve the problem and prevent it from happening in the future. most of ours are for relatively minor things like we didn't rev up a drawing properly, or a weld detail was missing - not something you'd revoke a U stamp over.

abangbikerz: it is not bad practice to stamp pipe. it is bad practice NOT to stamp pipe. however we do use low stress stamps on cold temp pipe. if it was bad practice our provincial inspectors would not require us to do it.
 
In lieu of marking, appropriate records may be filed.
Marking is useful during construction, appropriate records is useful for ever.

Regards

rhg
 
What I do to maintain heat numbers is have a dedicated set of ISO drawings that only have Heat Numbers recorded and pointing at each item. More times then not you will have different heat numbers on pipe, fittings, etc, as you know. This has been the easiest way for me and made the client happy. I filed them in with all of the corresponding MTR paperwork. Organize your MTR's into pipe/fittings/flanges/valves. Makes it very easy to track down if anyone asks. I will also do a cover page for quick reference of heat numbers lists matching what they are for. Just a simple excel spread sheet.

It is the responsiblity for the material controller to let the crew know what material is to be used so everyones paperwork can jive. It is the pipe fitters responsibilty to transfer the heat numbers onto his "Issued for Construction/Fab" drawing and also to trasnfer heat numbers on cut lengths of pipe.

hope this helps.
 
I would assume that received materials are properly marked (usually stencilled) by the manufacturer and that as bits and pieces are used, these markings are transfered by the workers so that all bits and pieces remain traceable.

I would also assume that if full traceability was required, as components are attached to the vessel during fabrication, some sort of a map should be generated showing which heat codes were used for the various parts of the vessel.

I would not assume that each part would be identifiable by visual examination after completion of fabrication as paint / stencil markings would be lost during fabrication and painting. Regarding stamping, the most common situation locally where people want full traceability is sour service and then in sour service many end users specifically try to avoid any stamping of identification marks (although low stress stamps are available).
 
shamino You're in a tough spot. When I get to this point, I have a long chat with the "big boss" Owner, CEO, etc. If the shop-floor supervision will not enforce the ASME-required traceability requirements, your company no longer has any right to a Code-Stamp.

The problem might be training & education. The shop foreman and/or the workers may not know about the *absolute* requirement to transfer #'s prior to cutting. Make sure they have been taught. After that, it is up to them to do the work. It is *mandatory* that you prowl the entire shop MANY times a day. "If you can't care enough to check, how can they be expected to care"

As a temporary measure, you can do what we did when making nuke plants -- put a HOLD-point on all cutting of Code material. You expeditiously go to the saw or burn-table and verify accurate transfer of the heat # to all the pieces being separated from the big piece. I also prefer to take a paint-stick and write "QC OK" and my initials on each and every part being severed off. Then you file an Inspx report/memo into the vessel traveler package stating what happened.

Until you educate the "big boss" and the shop foremen, and the working craft; you cannot fix your problem. You may end up needing a Receiving clerk/Inspector, that also roams the shop floor to transfer heat numbers. But SOMEONE has to be doing the required markings PRIOR to cutting, and YOU [one someone working for you], or the cognizant foreman, has to keep ensuring HOURLY that the Code-required markings are staying on the Code materials. It's tough until EVERYBODY on the shop floor has "bought in" to the program and is conscientious about it.
 
Duwe6, very good practices. Star for ya
 
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