Not logged inAmerican Welding Society Forum
Forum AWS Website Help Search Login
Up Topic Welding Industry / ASME Codes / QW-466.1 Test JIG Dimensions
- By Markzhou Date 04-12-2013 02:48
In QW-466.1,there is a table,Under the table,there is a column heading "materials", what does P-No.23 to P-No.21 through P-No.25 mean ? Does it mean the base metals of the specimen are P-No.23 and P-No.21(or P-No.22 or P-No.23 or P-No.24 or P-No.25)?  And P-No.21 through P-No.25 With F-No.23 means  the base metals of Specimen are both P-No.21(or P-No.22 or P-No.23 or P-No.24 or P-No.25) and they are welded together using filler metal F-No.23? I'm a fresh man and will be very appreciate if someone could give me an answer.
- - By 803056 (*****) Date 04-12-2013 16:48
P numbers are groupings of base metals. The P2X are aluminum alloys. The materials listed in a particular P number have similar weldability.

In the case of P23, the ductility is rather poor, so the bend diameter is larger than the other P2X groups. Likewise, filler metals grouped as F23 have poor ductility, so if a F23 filler metal is used the bend diameter is increased to compensate for the poor ductility.

You should also note that the bend specimens are reduced to 1/8 inch thick. The root surface is remove if performing a guided face bend and the face surface is removed when performing a guided root bend.
When possible, I qualify the procedure that involves either 6061-T6 or 4043 filler metal using 1/8 inch material to save time and money by eliminating the need to machine the test pieces before bending them.

Good luck - Al
Parent - - By Markzhou Date 04-14-2013 03:14
Thank you for your reply .
In your reply, you said you qulified the procedure that involves either 6061-T6 or 4043 filler metal using the 1/8 inch material. Does the 1/8 inch mean the thickness of test coupon?
I think the 1/8 inch is not the thickness of test coupon, but the width of specimen,see QW462.2 "W".
The thickness of the test coupon is determined by the product thickness . The product thickness must in the range of qualified base metal thickness,isn't it ?
I'm not sure. you are AI ,your understanding of the codes is more precise .Thank you again.
Parent - - By 803056 (*****) Date 04-14-2013 19:34 Edited 04-14-2013 19:47
Please read the third paragraph of my response one more time. When testing P23 base metal or using F23 filler metal, the specimen thickness must be reduced to 1/8 inch before performing the guided bend test. So if the welded test plate is anything thicker than 1/8 inch, lets say 1/4 inch or 3/8 inch, a machining operation is required before any bend test is performed. If you are welding thicker test coupons you can use Side Bends in which case the width is 1/8 inch as you mentioned. Just make sure you are placing the specimen in the test fixture properly. Machining is the typical means of producing the proper sample dimensions with parallel surfaces.

If you are doing a Face Bend, the material is machined from the root side of the welded specimen. If you are doing a Root Bend, the material is machined from the face side of the welded specimen.

You will note that the P23 and F23 materials tested in the as welded condition require a very large bend diameter. This is due to the poor ductility of those materials once they are welded. If you were to test 3/8 inch think specimens, the bend diameters would be very, very large. Machining the specimens reduces the need to have relatively large testing fixtures. The same procedures/techniques are followed by AWS D1.2 and AWS B2.1.

I strongly suggest you use a wrap around bending fixture.

"Aluminum; almost a metal."

By the way, I am not an Authorized Inspector, just a SCWI.

I hope this clarifies what I had posted in my earlier response. Good luck. Do not get discouraged if the samples fail the first time you attempt to weld it. Cleaning is very important.

Best regards -Al
Parent - - By eekpod (****) Date 04-15-2013 11:02
I made the mistake of using the wrong bend radius and also missed the part about the 1/8" thickness once.... the results were horrible everything broke.  Once I realized I was testing it wrong the results were much better.
Parent - - By 803056 (*****) Date 04-15-2013 13:17
Inspection Trends has two good articles in the last issue. One article dealt with "routine inspections" and the problems that can be encountered when we do not review the welding standard before forging ahead with the work. I hate to admit being chewed on by that mistake before.

The other article was by our good friend Brent regarding going it alone as an independent contractor performing CWI work. I usually get one e-mail a month from CWI's that are entertaining the idea of setting themselves up in business.  As any welder that has done the same can tell you, "it ain't no bed of roses."

Best regards - Al
Parent - By welderbrent (*****) Date 04-15-2013 15:10
Thank you Al.

I found the articles on 'How to Handle 'Routine' Inspections' and 'Tips For Working Overseas' very helpful.  Very good points made in both.  And, the Tips For Overseas can also apply in many ways right here when going to the far ends of our own country.  Language in the NE can be an adventure for a life long West Coast person.  As can culinary incounters, unexpected occurances, etc. 

Application to this thread: The insights on 'Routine Inspections'.  Very good points made about preparing for the job and not letting things catch you off gaurd because you lapsed into complacency and/or apathy in regards to checking the specs, applicable codes, and other pertinent information.

Have a Great Day,  Brent
Parent - - By Markzhou Date 04-15-2013 14:33
Thanks ,I have  got what you meant.
Parent - - By 803056 (*****) Date 04-15-2013 17:59 Edited 04-16-2013 19:50
A good friend just reminded me of an important point that should be considered when welding aluminum.

Unlike steel, it is not easy to select an aluminum filler metal that will provide suitable compatibility and the desired mechanical properties when welding aluminum. If you look at the filler metal specifications for aluminum filler metals you will note that there are no mechanical properties listed. That is because the properties of the welded joint is very dependent on the combination of base metal(s) and filler metal selected and the amount of dilution as well as the time at temperature (when welding the heat treatable alloys).

It reminds me of one of my earliest consulting jobs. I was called in because the client had 32 welders that could not pass the qualification tests. As soon as I arrived on-site I checked with the welders to see what they were doing. They told me and I recognized that the filler metal was not one that is usually used with the particular aluminum alloy they were working with. I asked why they were using that particular filler metal and they responded it was what their engineers specified. Next I asked for copies of the WPS and supporting PQRs. "What's a WPS and what is a PQR?' was the response.

Long story short, the welders were never going to pass a bend test using the filler metal specified by the engineers. The fillets looked as pretty as a picture, but they were brittle as glass. We qualified a new procedure with a filler metal I selected based on some research and everyone passed the bend tests as well as the fillet tests once we had a qualified WPS.

"Aluminum: almost a metal." You don't know what you have until you test it!

Best regards - Al
Parent - By Markzhou Date 04-17-2013 03:55
Thank you AI.It's very useful information.That will really helps me in both procedure and performance qulifications.
Up Topic Welding Industry / ASME Codes / QW-466.1 Test JIG Dimensions

Powered by mwForum 2.29.2 © 1999-2013 Markus Wichitill