Proof test before qualification D17.1:2001

By Lawrence (*****)

Date 04-10-2007 23:43

Tam

There is too much wrong to comment on everything so we must start with the obvious.

1. Those tests mean nothing according to D17 until you qualify the procedures for each alloy and thickness group, before welder performance qualificaiton tests can begin.

2. 7075 aluminum is unweldable... This should be known by even the most junior process engineer in the aerospace industry.

3. The back sides of both the stainless and titanium showed flush contact to a chill plate at the fusion line and oxygen/nitrogen contamination.. no way will you get full pen and quality without a relief groove fixture of some sort and argon backing.

The good news is that the tops of some of those beads looked ok..... This means with qualified procedures and some process control training, your welders can learn how to deal with each alloy... Yes training for each alloy is going to have to take place. But a guy that can make a good tig bead can be trained fairly quickly to the level necessary to pass a D17 cert test.

You need help Tam. The job you are undertaking takes a top level expert in GTAW and materials behavior as well as much experience in procedure qualificaiton.... Hire a consultant until the initial procedures and welders are qualified.... glue yourself to him and learn... Than send him on his way and take over.

By TAMPALUIS (**)

Date 04-11-2007 13:30 Edited 04-11-2007 13:43

thanks Law, I needed to know this. I am learnig too much.
Our first action will be to contract and expert to train our welders and develop the qualified procedures according to the codes and the expert. But I have some questions.

3.
- Does Discoloration apply in stainless steel quality weld? I ask this, because the acceptance criteria in D17.1 code says me that all oxidation colors are acceptable.
- Another thing is, Does the relief groove fixture apply to both stainless and titanium or only for titanium? A cooper, aluminum or mild steel fixtures are recommended, are they?
- Could you explain me better the follow sentence "showed flush contact to a chill plate at the fusion line", And what would you recommend me?

Thank you very much

By TAMPALUIS (**)

Date 04-12-2007 14:33

Good day, excuse me, I forgot to mention a "little bit" detail, the position of the test was 3G, I don't know if your opinion would be change, please tell me.

I want to request you something, the situation is that the code says me the colors that are rejected and accepted but I think that this appreciation is subjective, so where cuold I find images that incates me the colors?

thanks

By 803056

Date 04-12-2007 17:59

Hello Tampalus;

Many of the questions you ask are pretty basic to welding.

There is an organization in Caracas, Venezuela that has a four day class on the Fundamentals of Welding Engineering. You should contact them to see when they are going to have their next class. It may be worthwhile for you to attend the course. The course is in Spanish, so it will be easier to follow than if it were taught in English.

Here is the contact information:
Tamara Moscol

Gerente Comercial
IBEC - S.A.
Telefono: 0212-976.7356
Fax: 0212-976.7554
E:mail: ibec-sa@cantv.net

Best regards - Al

By TAMPALUIS (**)

Date 04-17-2007 14:59 Edited 04-17-2007 15:12

Good day, I know that a basic course is required and I am finding out it. But, is very important for me that you help me with the request that I maked in my last comment, about a color chart sample, because I need to teach to my welders what is this. Please, could you tell me where can I find this chart?

thank you

regards

By 803056

Date 04-17-2007 15:09

Hello Tampalus;

One of the attributes used to evaluate titanium is the color of the weld and the heat affected zones. Most companies make up a series of samples which have varying degrees of oxygen contamination. No contamination will produce a silver weld, slight oxygen contamination will produce a slight straw color, etc.

I am not familiar with any samples that can be purchased. That doesn't mean the samples are not available from someone. I will check with some of my associates to see if they are available for purchase.

Best regards - Al

By Lawrence (*****)

Date 04-17-2007 19:47 Edited 04-17-2007 23:31

Hey Al

The posts from Tampalus scare the crap out of me...... I just know this guy's employer is already busy reworking/destroying aircraft componants and he is just playing catch up for some ISO audit. As hard as he tries, the guy and his operation are in totally over their heads and I can't seem to get that point across...

I want to be helpful, but I also don't want to give him enough information to allow him think he has his problems licked when in fact he really has not even started to deal with them in any productive manner.

I don't want to fly in a plane who's titanium LPT cases are being repaired by this company

Just don't know what to do

By TAMPALUIS (**)

Date 04-18-2007 13:48

Good day Law, respectfully I think

Obviously, the company will not make a weld repair until we will be compliant with all quality standars and practices that are required by FAA and AWS, that's why we are developing a project to certified our procedures and welders by the AWS, this roject includes research and training, but I know that I need help to realize that and I looked for the forum help, because I believed that it was a great "tool". I don´t want that you develop me my project but I want that you can solve me many doubts and get me some recommendations.

"I know that IT IS THE AVIATION INDUSTRY"

And thanks to Al, because I think that he understands me.

Thank you

By Lawrence (*****)

Date 04-18-2007 14:05

Lucho

Please forgive me for sounding negative.

Having worked in the aviation industry for many years I have actually seen vendor repairs come back with such terrible workmanship that sometimes the parts themselves could not be salvaged.

It's encouraging to know you are preparing to do the work rather than doing the work while you prepare (as some actually do)

Again.... I regret my negativity in the above posting and won't let it happen again.

Lar

By TAMPALUIS (**)

Date 04-18-2007 15:11

Hello Law,
Don't worry, also I apologize because, maybe I have not been clear enough in my post. I know that I'm rookie in this topic, but that's why I want to learn too much and give to my company all my knowledge to get the goal (Excellent and quality services for aircrafts).

thank you

By 803056

Date 04-17-2007 21:18 Edited 04-17-2007 22:44

Hello Lawrence;

No argument with your comments. That's why I suggested the course offered in Caracas. It covers the basics needed to make the engineer aware of potential problems and to recognize when outside "help" is needed. Many people don't know they need help because they don't recognize the problem as being a problem. He's using one of the best resources I know of, this forum. Our friend recognizes he needs help and he's asking for it.

All of us had to learn about welding and for most of us it was by attending the "School of Hard Knocks". None of us were born with the knowledge we have today and most of the knowledge was acquired over many years of reading, asking questions, and burning rod. Some of us were lucky enough to attend good schools with good instructors, some of us learned on-the-job, some of us worked our way through apprenticeship programs that gave us the training and information we need to ply our trade. The touchy part of this thread is that if the welding is faulty, many people can get killed.

You have to wonder about the airlines that (currently) do or are considering outsourcing their work to subcontractors that have limited experience in aerospace welding. And where is the FAA while all this is happening? Maybe these aircraft don't fly to the States and don't have a government watchdog agency (who is in bed with the airlines tighter than a bed bug) to contend with. Then again, I've seen some very scary stuff right here in the U.S. and wonder how there isn't better oversight. As they say, "a few people have to die to save the multitudes". Remember ValueJet? "Come fly the friendly skyyyyyyyyyyyyyyyyyyyyyys." I think about it every time I board a plane to fly somewhere in this wide world, and it is usually once or twice a month that I look at the emblem on the engine nacelle and the side of the aircraft and ask myself, "What did this manufacturer do to vet out the poor performers or was this the lowest price quoted, qualifications be damned!" I used to fly if it took me more than four hours to drive, now I am happy to drive ten hours before considering flying the unfriendly sky in an aluminum can with my knees tucked up under my chin. Don't get me started on rant about the airline industry!

Best regards - Al

Al