The company I work for wants to get into bridge fabrication and I will be the welder doing their first PQR test. Ive been told I will be doing 2 weld tests in FCAW-G, both 1G but one at the low voltage and amp range and the other at the high end. The CWI (new to d1.5) also says that travel speed is to remain the same for every pass and no grinders are to be used. Ive skimmed over the code book and some things are quite stringent compared to other codes it seems. Monday we are going to have the test and a state inspector I believe will also be there so Im sure I will get more info on exactly what will be going on.
I suppose Im just looking for advise or tips from the other welders that have done this before. For example, how much will I be allowed to vary the travel speed, how much of a range do you have the low and high end tests? I just have little questions like that, not 'how to weld' questions.
Any experienced minds care to shed some light?
Alan domagala
Maybe you should edit this question a bit, 400 ipm, that is moving try 400 amps and 10-12 ipm.
You will not be able to vary much from thePQR
Heat input Will be an issue that needs to be confirmed. The PQR will determine the limits of your future WPS's
Good Luck
Marshall
Thanks for catching that! I was typing to fast and wasnt thinking!
Being Monday, this may be too late - fit your backing bar TIGHT, TIGHT, TIGHT! and run your root in 2 passes one each side. You need to pass RT first and indications at the root are the #1 cause for failint RT.
D1.5 does not prohibit grinding on the PQR test. It does for the welder qualification tests.
There is some difference of opinion as to whether grinding is allowed on a PQR if is will also serve as the welder's qualification - for that it's best not to grind and avoid issues.
I don't know why the travel speed cannot vary, seems to me that it could but I don't know the circumstances of your testing.
CHGuilford
Travel Speed is an essential Variable according to Table 5.3 (11). AWS D1.5 2002.
It affects heat input and cooling rates this is especially important for Fracture Toughness control and for welding quenched and tempered Steel.
Marshall
I am very aware that travel speed is an essential variable.
My point is that for a min/max heat input test, it is highly unusual to run both tests at the same travel speed. In fact, the main advantage of the min/max tests would be to gain a wider range of variables than would otherwise be allowed by the 5.12.1 max heat input test or the 5.13 'production procedure' test.
Right Chet, if you are only going to be doing the one test plate, then you would want to keep the travel speed consistant, but if he's running two plates for the min and max, he would want to change the speed to get a bigger range.
CHGuilford
Well excuse me for answering your "I don't know why the travel speed cannot vary, seems to me that it could but I don't know the circumstances of your testing." reply.
I will give it to you the same as I do my wife,
I ain't no mind reader if you say I don't know, how am I to know you really do know
But I am wondering why would you say "I don't know why the travel speed cannot vary" if in the next reply you can say "I am very aware that travel speed is an essential variable."
Isn't that why because it is an essential variable.
I just thought I was confused.
And nowhere did the O.P. say same Travel Speed for both tests, He said "The CWI (new to d1.5) also says that travel speed is to remain the same for every pass"
If the person developing the PQR requires the same travel speed on both tests, durn if that would be what I tried to do.
Marshall
Marshall,
Whoa there! No personal slam was meant by that. And you are right - I did misread that. I apologize for offending you - I'm just a bit too blunt in my thought process at times and really should learn to slow down in speed reading these posts. Again, no offense intended.
Chet
None taken and I too have problems from time to time like misreading and being too blunt.
I started to query the O.P. for more information but when I pointed out a couple of discrepancies He removed them completely.
From that point on I really didn't have enough info to rightfully answer but you know how I am,Just a think I Know it all Inspector. LoL
Have a Better Day
Marshall
Too late now, but...
The code doesn't specifically address how much you can vary the travel speed from pass to pass, but you need to keep them pretty close or else your test is meaningless. (Welding half the plate at 5 ipm and half the plate at 15 ipm is NOT the same as welding the whole thing at 10 ipm.) The code pretends like the whole PQR was done exactly the same way, and then the WPS can vary a certain amount from "the" parameters used on the PQR. +/- 10% should be pretty good. (I think the next edition of D1.5, whenever that will be, is supposed to put in some explicit limits.)
But really, you have no reason to be doing a 1G FCAW test as semi-auto. Put it on a buggo.
Hg
Thanks for all the replies. They set up a buggo with a pointer and I followed it as I welded the test plates so the travel speed remained the same for each pass. Its no problem welding them of course, just kinda strange.
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