Field Testing Full Penetration Weld

By pipewelder_1999 (****)

Date 12-09-2002 22:15

AWS D1.1 98 says in Chapter 6 Para 6.1.1 indicates non destructive testing other than visual shall be specified in the information furnished to bidders.

Para 6.6.5 Says "If non destructive testing other than visual inspection is not specified in the original contract agreement but is subsequently requested by the owner, the contractor shall perform any requested testing or shall permit any testing to be performed in accordance with 6.14. The owner shall be responsible for all associated costs including handling, surface preparation, nondestructive testing, and repair of discontinuities other than those listed in 6.9...... However if such testing should disclose an attemt to defraud or gross nonconformance to t his code, repair work shall be done at the contractors expense."

I hope this helps a little

Gerald Austin
http://www.weldinginspectionsvcs.com

By DGXL

Date 12-10-2002 00:05

One more thought to consider:
If these moment frame welds are being performed in seismic zones 3 or 4, then the testing IS required by the Uniform Building Code (UBC), Chapter 17, Section 1703. The IBC states the same, but goes a different route and references the AISC Seismic Provisions. This takes you back to "...approved nondestructive testing methods conforming to AWS D1.1."

There are maps in the code which delineate which seismic zone you are in as well.

If the welds are failing at the rate you say, then they would be considered "gross nonconformance" to the code. The Contractor would then be liable for any repairs. That's the way it goes down in the courtroom.

By curious Date 12-10-2002 20:44

You are all helping so much, thank you.
We are in Zone 1. Thank you for the heads up. We have talked to the engineer. It is his interpretation ... "that the type and extent of inspection be stated on the contract documents so that the contractor can price the inspection for bidding. But since the owner is paying for inspection it is a mute point. Regardless of the fact that the specification states visual inspection, when the weld were made through painted surfaces it became an issue that contaminants were known to be present and testing the weld by ultrasound would be the only way to verify integrity of the weld. Based on results of the UT it is quite apparent that there were a significant number of defective welds."
My questions: 1- Can the paint be burnt off in the initial passes and not be an issue? 2- The spec said visual testing. My interpretation is that anything that fails visual would be the responsibility of the contractor to fix. Any defect that passes visual and fails UT would be the owners responsibility. Am I off course. 3 - If the welds are passing visual, then this wouldn't be gross nonconformance, would it?

By jon20013 (*****)

Date 12-10-2002 21:26

I think Gerald Austin summed it up nicely and in Code language. As long as the welds passed visual (which is all that is REQUIRED by D1.1) then all other costs associated should be taken by the owner. If the welds passed visual examination they would not be considered grossly non-conforming but some scrutiny in the inspection practices may follow, depending on the magnitude of indications. In other words, if repair uncovered gross defects the question may arise as to the effectiveness of inprocess inspections.

By jwright650 (*****)

Date 12-11-2002 13:22

I too have seen some "pretty looking" welds only to find out when I UT'd them, they were pretty on the outside only. I feel full pen welds should be checked other than with just visual. On the other hand if visual is all that's called for in the owner's specs, then you get what you pay for.

I check 100% of all the full pen welds that go out of this shop, only to ensure our customers that when thier drawings called for full pen, that's what they got, good sound weld. We have another shop about 350 miles from our main shop. When I first started Inspecting at that shop, I had lots of full pen welds failing UT. They told me, "If I knew it was going to UT'd, I would have done a better job". So, my response was, that if the drawing called for full pen, then they should have treated it like it was going to be UT'd or RT'd and no short cuts. After these guys cut out all that weld (dozens of W14 x 500's and W14 x 550's column splices), they had very few welds out of hundreds, ever fail UT again. That shop became proud of thier welders and trust was gained in thier ability to produce good sound welds and that no one had to worry about them when thier fabrications got to the field, whether or not it would be UT'd. Going alittle further than asked, gives your customers more confidence in your shop and it does not take any more time to do it right the first time. That results in work being directed your way when times are lean or when you are not the lowest bidder, but they know you'll do a good job for them so they use you over the lowest bidder.
Sorry, I don't have the sympothy for the welder that has to fix his welds because he didn't pay attention and keep his welds clean and it failed UT. I think it makes him a better welder when he knows where he went wrong and next time there will be better results when his welds are checked, other than visual.

Sorry for the rambling's about our welders, but I was remembering what I was told the first time I heard, " I didn't know it was going to be UT'd".
John Wright

By curious Date 12-11-2002 13:57

What do you know about the issue with the beams being primed before being welded? How does this affect the weld. Around here I'm hearing mixed information. Thank you all for the information. I do agree that if you are going to do something, do it right. I also can understand following plan and spec. Thanks for the input this is a tough question.

By jwright650 (*****)

Date 12-11-2002 16:26

Our shop has made mistakes and painted the ends of beams that were prepared for field welding. The erector had to grind and burn off all that shop primer before the Inspector on the jobsite would allow any welding to be done. Most shops use a shop primer that is nothing more than a water color paint, but the joint still should be masked off for field welding. Actually, the shop drawing should indicate where there is "no paint" to be applied. Like beam ends at field welded moment connections, and the column faces where these beams get welded to, etc...
I'm telling all this to hopefully keep someone else from making the same hard mistakes we have made and learned from in the past,
John Wright

By jon20013 (*****)

Date 12-11-2002 20:01

There are primers which are perfectly acceptable for welding over but you have to be really careful because many of them look identical to their "non-weldable" counterparts, many of those even having near identical chemicals. As an engineer, I would not have a problem specifying a weldable primer for those joint areas needing protection but at the same time, I would not substitute any "similar" primer in these cases. Moment connections are always viewed using very tight criteria ~ my guess is whomever put your spec together calling for visual only missed the boat. Never-the-less, if your spec called for visual and subsequently failed UT, repairs will obviously have to be made but those repairs should be at the owners expense.

By DGXL

Date 12-11-2002 22:09

Curious:
In your original post you stated that many welds "are failing", approximately what is the failure rate percentage-wise?

By curious Date 12-17-2002 16:40

I am not sure - I think the first ones failed about 60%, they reworked them and still had some fail maybe 30%. The information I get from the testing and the welders is a bit different. Since my initial question the erector has had a different company come in and retest the failed welds in another area. They contend that some of them would pass. I am not privy to this information yet. It's getting pretty murky at this point. Currently the bottom line is that the engineer holds that the beams should not have been painted and that affected the quality of the weld and now they should be fixed but not at the owner's expense.

By CHGuilford (****)

Date 12-17-2002 17:48

All this is interesting in a couple of ways. First, I'd like to have a dollar for every time that another inspector is brought in because the first one's decision wasn't very popular. Sometimes it is justified, and sometimes not, but I have to chuckle every time it happens.

Secondly, although the owner pays for repairs on defects found by unspecified NDT, it becomes negotiable when a lot of repairs are needed to bring welds up to code minimums. I would say 60% just might be approaching "gross nonconformance" especially if 30% of the rework failed. (I will assume here that the NDE personnel know what they are doing. If that is not the case then, as you said, it gets pretty murky.)

As far as only requiring visual inspection initially, I just want to point out D1.1-2002 Sec 6.1.2.1. It tells me that the contractor/fabricator is supposed to provide for inspection in all phases of welding, including during welding. That would mean joint prep and geometry, between passes and so forth. If 60% of the welds failed UT, I would say there were problems that should have been obvious and should have been corrected before "burning another pass over them". Now I wouldn't expect the inspector to stand over the shoulder of each welder all day long. But I would expect the welder, who should be trained and qualified, to know when he/she should grind between passes in order to get a sound weld. That's a two edged sword to the contractor. He is responsible for what the welders do but no one can afford to watch over them every minute. And to be fair to the welders, they could have brought up problems with the welding joints and conditions, but were told to weld them anyway (not that THAT ever happens).
Irregardless, the owner could easily claim "gross nonconformance" especially if the 2nd NDT opinion comes anywhere close to the 1st.

CHGuilford

By jwright650 (*****)

Date 12-17-2002 19:50

You know, all this is very interesting and you have to wonder if it ever made it to court how would it turn out? Contractor/erector/fabricator to pay for repairs to weld they did, or Customer/owner to pay for weld to be repaired that the contractor/erector/fabricator did? Somehow, I feel the Inspection can get very picky, but they do have guidelines to accept or reject by.
I hope curious will let us know how all this washes out. Sometimes Customers/owners look for ways to get more for thier money, and it might be at someone else's expense. Sometimes Contractors/erectors/fabricators will not take proper precautions to ensure good welds to save time or money. Lots of variables can lead to this very situation. Other trades may end up being involved in looking for money if they are held up waiting for welds to be repaired. Block masons caught us on a job we had, when welds had to be repaired and we had to pay them while they sat and watched our erector weld up full pen joints. We had to hire another welding crew to come in and help with the welding so not to hold up the block mason any further. We learned the hard way to make sure paint was masked off of the field welded joints. It takes time to get in there and clean paint off before welding. I sure would not even think of welding over painted joints if it has to be full pen, even weldable paint will give problems if it has too many mils applied.
Keep us up to date on how this one turns out,
John Wright

By curious Date 12-18-2002 21:21

You are right. There are so many variables. The engineer has admitted that he really did want to spec UT testing but used the architect's spec. The fabricator and the erector are under separate contracts to me. I am gc. We all want a good job everyone can be proud of. I just cannot understand how so many of the welds are failing. I am begininning to believe it is a combination of the strictness of the testing firm (failed twice as many as the 2nd firm), the paint on the beams, the weather conditions, and bad karma. In any event, my job is at standstill on this building until someone agrees to pay the erector. He refuses to do any more repair on his own. He has repaired about (probably over half) half of it now at his own expense. We are trying to get the fabricator to pay for this last half but he is balking. The engineer is just trying to be sure the structure is wholly sound. Something I haven't mentoined before now is that these welds are on a curved wall - horizontal beams to tube column moment connections. The engineer was leery of these field moment welds to begin with as he had the fabricator hire an engineer to design them. But that's another whole story. I will let you know how this plays out. I'd like to see fabricator, erector, and owner split the bill three ways. But we'll see.

By Michael Sherman (***)

Date 12-17-2002 20:59

I have withheld my opinion, and it is only my opinion, on this because I wanted to see where it was headed. I believe the fabricator has a serious problem with his quality control. The owner has every right to check the welds in any manner he sees fit, if he pays for it. Possibly, he had reason to suspect the fabricator was not doing the best possible job. Personally, I say it is gross non-conformance way, way before you come anywhere near 30% failure. Not to mention 60%. If I am contracted to do a job and my welds are failing, I will spend every last dollar I have to correct the problem. Where is this contractors self respect? or morals? Does he care so little about his reputation? If the contractor would come forward and talk to the owner and admit culpability, most times there can be a compromise on the expense. I am constantly amazed at how much time and effort is put into trying to avoid responsibility in our industry. If you can't make acceptable welds, or least accept responsibility for the welds and mistakes that you do make, then get out of this business. I'll step down from the soapbox now.

Mike Sherman

By DGXL

Date 12-17-2002 23:17

60% could be considered gross nonconformance.
Painting the ends of welded connections, welded moment frame connection which should not have any paint at girder ends to begin with (which acts as a lubricant for a connection which is supposed to resist slippage).

At that rate, most would require testing of all welds in question.
I think there's a line forming behind your soapbox Mike.

By jamesbg (*)

Date 12-18-2002 09:16

I have been a subcontract moment welder for 20 years and would be glad to offer my services if they are still needed.just give me a email at
jamesgezelman@adelphia.net I would also be willing to give a price on any job requiring moment welding and colume splices.

By Michael Sherman (***)

Date 12-18-2002 14:19

Another thought occurred to me last night concerning visual inspection. It seems many people interpret it as being the cover pass or cap only. Proper visual inspection starts with the raw steel and encompasses every aspect of the welding process from initial preperation to the final cover pass. Paying attention to accepted welding practices (even on a rudimentary level) and a welder who knows he will have to repair it, and be removed from the job if he is a habitual offender, will solve most problems. Proper visual inspection will give extremely good welds if done properly and consistantly.

Mike Sherman

By jon20013 (*****)

Date 12-18-2002 18:41

Michael; I couldn't agree more with your response, in fact, AWS D1.1-2002 (and every other edition I am familiar with) is very clear as to the scope and extent of examinations to be performed. Having said that however, in my mind, some of the responses in this posting are off-course (again, this is simply my opinion!). If there are an excessive number of "defects" determined by a contracturally unspecified NDE Method (except visual), I think that "attempt to defraud" or "gross nonconformance" would be a hard one to prove unless there was something very clear, like slugging the welds involved. Naturally, this is just my opinion!

By Michael Sherman (***)

Date 12-18-2002 19:22

Perhaps incompetent would a better description. I know that gross nonconformance is difficult to prove, I have for the most part expressed my opinion and my extreme dislike for people who do not accept responsibilty for their actions. I see far too many people on this format and in my everyday encounters who are spending a considerable amount of money trying to get out of what is clearly their responsibility, if only from a moral point of view. I know that it is possible to be successful and still be responsible for your actions, and atleast I sleep well at night. Merry Christmas.

Mike Sherman

By CHGuilford (****)

Date 12-18-2002 21:51

That's the point I was trying to make with the reference to D1.1 Sec 6.1.2.1, that inspection starts with the fit-up. Gross non conformance only means non conformance on a big scale. 60% reject rate with a 30% rejected repair rate tells me someone is not conforming to the code on a big scale. Intent to defraud is difficult to prove, but but I think the owner may have solid footing for requiring the contractor to pay for the repairs based on nonconformance issues. It's a good lesson for everyone to be aware of what can happen if we don't apy attention.
CHGuilford

By Niekie3 (***)

Date 12-18-2002 20:13

I am not a D1.1 fundi. As such I do not want to make any comments regarding the whole "gross non-conformance" debate, but would like to approach the problem from a different angle.

In design codes, the NDE called for is largely a function of the risk involved in the service of a particular weld. In essence, what is said is that we will live with a larger risk of having a poor weld by compensating with higher safety factors. (In the end, NDE is merely a sampling inspection scheme. The bigger the sample, the higher the certainty of the quality of the products.) Just as an example, in ASME VIII, if 100% radiography is performed then a welded joint can have a joint efficiency of 1. If spot radiography is used, this drops to around 0.85. If no radiography is called for, then the joint efficiency drops further to 0.7, if my memory serves me well.

As such, it can be argued that welds requiring ONLY visual inspection already have a factor built in to compensate for defects that will not be detected. It may therefore not be expedient to use the same acceptance criteria when performing this additional "uncalled for" UT, as that specified for joints where the UT was specified.

All this said, if I was the client, I would be very uneasy that my building may have serious defects. I would therefore suggest that a "fitness for purpose" expert is called in to actually perform the relevant calculations and give a ruling on what would be the most appropriate acceptance criteria for the UT inspections. Any not meeting these requirements should be repaired at the fabricators cost.

Hope this helps

Regards
Niekie Jooste

By jwright650 (*****)

Date 12-18-2002 21:25

Niekie Jooste,
To add anything extra to what has been said would be hard, but in D1.1 regarding the UT inspection there are clear cut accept and reject criteria. Provided this was followed by the UT tech. AWS has already done thier homework to provide such criteria to go by. Therefore maybe the fitness for service inspector(if hired) could use the information gathered by the UT tech. to provide his analysis. The UT tech should have reports containing info about what, where, and how much, on each joint in question. VT like has been stated already should have been done and if the Inspector saw a welder not preparing a joint correctly(paint still on the surfaces of the groove faces) and let this welder continue, then shame on him. As I was typing Curious has replied with more info, so I'll stop my opinions until I've read his new post.
John Wright

By Niekie3 (***)

Date 12-18-2002 21:58

I agree that the acceptance criteria is specified in the code. These criteria are however aimed at a situation where UT is called for. Where UT is not called for, there is theoretically no acceptance criteria. - Why give acceptance criteria for a test that is not to be performed?

I re-state that I beleive the issue at this stage is a "fitness for purpose" issue rather than a code compliance issue.

Regards
Niekie Jooste

By jwright650 (*****)

Date 12-19-2002 12:50

Curious,
As you can see there are several opinions posted, which is good, you will now have several views to consider. After reading your last post, I'm not sure I know why you would be asking the fabricator to help with funding the erectors weld repairs. Maybe contracturally they are tied somehow (Maybe designing and detailing the connections being welded?)and you just haven't said. I'm partial to the fabricator because I am a fabricator. For us, if this case was ours, we would be responsible, because we include erection in our quotes and the erector works for us, rather than for the GC.
Good Luck with your job,
John Wright