Responsibility of changes

[ChadInColo]

Here is a situation that I really hope nobody else has had to deal with, but hope someone can help me out with some advice or information.

I have a big project, major part of which are 2 weldments, one steel (primarily galvanized), one aluminum. All welding to be done to AWS D17.1, non-flight hardware (section 8 of the spec). We have 1 of the steel, 4 of the aluminum completely welded and machined (relatively tight tolerance). NOW, x-rays are brought up to prove the welds. Contract is changed, we explicitly state we are not responsible for what x-rays find, have the films shot and interpreted. Worst thing that could happen, did. Porosity/incomplete fusion in the steel, porosity/cracks in the aluminum.

We submit paperwork, stating adding x-ray requirements means the parts need repair, ask for direction. Reply comes back, saying adding x-ray requirements not to blame, welds were not good before requirement was added, please revise paperwork, telling me they plan to try to push responsibility to my company (doubtful repairs can be made and maintain flatness, other requirements, expensive parts to scrap).

Who is responsible? I understand we didn't meet the new requirements, however the welds were accepted by an outside weld inspection agency (who was inspected and approved by the customer) to the original requirements. Do I have a leg to stand on saying that adding the x-ray requirements is what caused the rejection, therefore adding the requirements makes the customer responsible?

If anyone was in a similar situation, or knows more of the ins and outs of how this is "typically" handled (if there is such a thing) please let me know. Also, since it will probably be asked, we are working to improve the welds, will soon meet the new requirements, only thing really in question is who is responsible for the "bad" units.

 

[Ron]

Two schools of thought....

1. If NDT (other than visual) is required, it must be specified in the bidding documents (According to AWS D1.1, Chapter 6, paragraph 6.1.1. The type and extent must be specified.

In the D1.1 Commentary, if further states that the Engineer has the responsibility to state the type of NDT and its application during the specification stage. It further states that though the Engineer may change provisions after the contract is let, he must recognize the contract conflict he places with his decision.


2. Fundamentally it should make no different whether the weld is inspected or not....the quality of the weld should be the same. In practice, we know that is not the case and AWS recognizes this as well.

I would try to negotiate at least some pay for the repairs.

 

[VeryPicky]

I need you to understand that I don't have the code in front of me and I am not fully conversant with AWS D17.1.


The big question is:

What were the original contractual requirements?
If X-rays were not a requirement than you are not responsible for any defects found.

Were X-rays the requirement than you are at fault.

Why do I say that?
In general the design of the weldment is based upon the presumption that the quality of the weld is known. Ergo: if 100% X-rayed than you can take 100% credit for the strength. If less or no X-ray (or UT) is to be done than the design should reflect that.

Now, what are you going to do?

I understand you have a valid case: the NDE was an addition after contract award. You can fight that.

On the other hand your comapny has produced inferior quality welds and you know it.


I suggest to ask the client about the design inputs and request clarification on what is the required quality level and design justiifed NDE level. Talk to the client, show them some professional pride and if needed share the cost of repairs. After all you need them as much as they need you and maybe more.

You have two choices: to be a problem or to find solution to the problem. What is your choice?



Putting Human Factor Back in Engineering

 

[ChadInColo]

Two very good replies, thanks.

VeryPicky, I wish it was that easy. The end customer (and design authority) is a foreign company, this is an export controlled product, meaning much government oversight, limiting my input. If the customer knew what they really wanted, it would be one thing, but they have come back and said (verbally, no contract) we don't have to get to D17.1's required levels for porosity, but need to do better. We are pretty much at a standstill until "better" is defined. Original contract was penetrant and visual, x-ray requirement was never mentioned until after welding had started on production parts.

Now, keep in mind, this was "engineered" (I use the term loosely, they didn't engineer, they built and tested, they don't know for sure if the factor of safety is 1 or 10) overseas, welded to a non-AWS code. I have their code, would consider it "antiquated", requires certain old practices that are no longer recommended in AWS. In strength my welds are superior, but porosity is present. Porosity was never an identified issue, low distortion was.

Now keep in mind also, customer has come back for "rebid" to get a lower price, we complied, cut some profit out because we thought it was worth it to keep the project, and for other reasons. Now, with the added requirements, we are getting nervous that this project may go from a good contract to a money loser. If we scrap a couple, then there is no question...

I don't know if this changed your views, but again, thank you both for the input, I am pretty well sure of my approach now. Thank you.

 

[metengr]

If I read your post correctly, the problem is that the original NDT requirements were modified after the original contract was negotiated and accepted by both parties - you and the Owner of the parts. You also fulfilled your obligation under the original contract by having some type of NDT performed and it was acceptable.

Now, it was decided to revise the original NDT requirements in the contract to reflect RT (X-ray) acceptance, and someone in your organization agreed to this change, as you stated. One cannot change contract documents unless both parties agree to the change in writing. Did you agree to this change in writing?

If you had NOT agreed to the RT acceptance criteria in writing or you agreed with the provision that any repairs required by RT defects would not be covered, you can supply the parts to the owner under the original contract requirements, and it would be their problem to repair not yours. IF you agreed to the change in NDT requirements in writing, you are required to make good on the deal. Sorry to be so direct, but this is how business is conducted these days. Always READ and UNDERSTAND before signing any contract documents!

 

[VeryPicky]

Chad

If the structure was not designed but proof tested and the NDE requirements were not finalised and so was not the quality level you have a real problem on your hand.

I hope you did not sign any contract addenda for that NDE. Because if you did you have to comply now.

The client seems to develop the engineering as you weld and this is not good.

I don't know how you could agree to fabricate the structure to a "better" quality level that is not defined.

I am not so much concerned with porosity unless excessive. Cracks and LOF are more of a concern. These are always undesirable and oftern rejectable if registrable by NDE. I would repair those.
Regarding problem solving seems to me now, that the client doesn't want to play along.

Regarding verbal communication: if not registered on paper - it does not exist.
Human memory is very short especially when trouble and finger pointing starts.

Putting Human Factor Back in Engineering