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D1.5 WPS/PQR

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MalinQC

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Oct 30, 2009
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My company hired me about a month ago as the QC Manager. I was an AI for 2 years, and in the navy for 9. I have lots of QC experience. I was hired on to help change things for them, and to promote growth by getting the company certified in the AISC SBR program. I have made the manual, and procedures required, but now I am putting together the WPS and PQR's for submittal with the application. My company has never welded on bridges. They have ASME stamps and all their weld procedures are based on Section IX, although most are wrong or outdated at best. As I have read through the D1.5 I noticed that the requirements are way more restrictive, and thus make things a litte tougher for qualification. We just bought a sub arc machine, at my request, and this will be the first test of that machine. I see in the D1.5 that it calls out for the use of of steel of having a tensile strenght of 50ksi or more, which isn't a problem. We use A36 on almost all work we perform, my issue regards using that material for test purposes. I don't have the ASTM Spec form AWS, and won't until January as my budget has run out, but I would like to set up my procedures for the test. Is A36 plate comparable to the required specs for D1.5, and if so, if using a 1" plate for testing, would backing be required or could back gouging be used in its stead? I know I posted a lot of info for such a short question, but like I said I am new to D1.5 so I want to make sure I get it right the first time.
 
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MalinQC,
- Good luck on this. There is WAAAAY too much info in AWS D1.5 to address in this forum. Even very specific questions can get extremely involved in this spec. See my earlier thread on the PQR questions. The best advise I can give you is to study the Code in great detail to learn the basics, and don't forget the comments section in the back.

- To address some of your specific questions, ASTM A709-50 (ASTM A572-50) would be the typical steel of choice to get started. A36 is not acceptable for PQR's (and maybe not for welder quals either). Backer is definitely NOT mandatory on welder quals, but may be required on PQR's depending on what you are trying to qualify. We have not done any SAW quals. There are specific req'mts for each welding process, so you need to study up on them.

- Some very strong advice, when ou can afford it, buy the electronic version of the code from AWS, and print out one copy. Keep the electronic one on your computer to do electronic word or phrase searches. This feature is a HUGE time saver when trying to find answers to certain key word questions or issues ... like "backer" for example.

- And lastly, study study study all of your essential variables in regards to "what do we need to do with this procedure" needs, and compare them line by line to "what is allowed" by code for this variable. This can save you lots of time and money if you do it right the first time, so you don't have to do another PQR to satisfy one little missed variable. As an example, we did a PQR with PWHT, but my CWI (for hire) only ran the PWHT cycle for the coupon thickness of 1"T, vs the production weld thickness of 4"T (plus an intermediate PWHT). We had to do it all over again with the much longer PWHT cycle. May as well have put five crisp $1,000 bills in the furnace with the coupon.

- Hope this helps get you started. BTW ... don't rely too much on your ASME background .. the bridge code is quite different.

 
Huh??? Where are you getting that D1.5 requires use of grades 50 & higher?

D1.5 requires working with grades of ASTM A 709. If you're building stuff to D1.5, in theory it will have been designed with the AASHTO bridge design code, and those are the materials you'll be seeing on the plans.

ASTM A 709 Gr. 36 is the same as ASTM A 36, plus some Charpy testing requirements. Talk to your mill; they'll probably provide you the same stuff only with a different specification written on the cert--if A 709 isn't already on the cert now.

If you are only going to be welding with Gr. 36, then you can run your PQR with Gr. 36.

The PQR test plate configuration is mandatory. See Figure 5.1. The reason it has backing is because there is a very wide root opening, and the reason for that is so that the groove weld is large enough to be able to get all-weld-metal tensile samples from it.

Hg

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HgTX thanks for your reply. As for where I got my info about D1.5 using certaqin strenght of metals, in the first line of the book, 1.1.1(1) it states the code is not intended for use w for steels with a yeild strength greater than 100ksi, and most of what is called out is the A709..Yes my A36 plate MTR's do list A709 as well, so that is a big plus for us. I am reading through this manual al little more every day. The problem really lies with the fact that my company has no true idea of what it wants to do with this certification, and is just getting it at a customer request. They said they wanted the capability of doing sub arc, and so that is what we are starting with since we have never done it here. I have seen a lot of software on the internet in association with putting together PQR's and WPS's, are they worth while and price?
 
If it's one of the pieces of software that simultaneously checks against the applicable codes, yes, I feel it's worth it for a company that needs to put together PQR's/WPS's without an in-house welding engineer/specialist, especially if you're starting from scratch and not trying to adapt old procedures (we contemplated trying to transition our old procedures into the new software, and it would have taken such a tremendous effort and amount of time that we declined). Be forewarned, they come with a steep price tag.

Of course, you also have the option of putting what you want together, then hiring an experienced CWI to come in and review things for you, which is often more economical.
 
Honestly, products we are making we don't really know. We do some steel girder work from time to time. It is for the Army Corps of Eng..I don't get a lot of input from my GM, he just says make this happen..I get the facts after the fact if you know what I mean.
 
If you'll be doing bridges, the cert makes sense. If you'll be doing non-bridge items, have your client take a look at the new AISC certification for bridge components.

If you'll be doing bridges, though, expect to be dealing in a lot more Gr. 50 and 50W than you've been doing.

Talk to your GM. Tell him that unless he wants a lot of money wasted doing the wrong PQRs, he needs to tell you what kind of products you'll be making. If you run the PQRs on Gr. 50W, that "downward" qualifies to Gr. 50 and 36, but if you wouldn't choose the same consumable for all those grades, you'd still have to run multiple PQRs.

Hg

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Okay, I have an update. I am starting the WPS qualification this week. We are going to use the A36 plate we have in stock, which saves us money, as it conforms to A709 gr 250 plate. I have a question now regarding the 5.12 qualification. I see there are several methods to provide a range of qualification, one of which is max values used on pqr which give you a operating range of 60%-100% in production. My question regards the use of max heat input, I plan on using a 1" plate like is called out in figure 5.1, and using a 7/32" SAW wire. my max heat will be the root, which I plan on using 1150amps, 36 volts (DCEP), at an 11IPM travel speed. Using the calc, I get 225 kj/inch. Is this too high, I read a lot in this same section of the D1.5 about an envelope of 51-71kj/in. I realize that is another way to qualify, but will my hardness be way too high this test? Also, I plan on using the minimum preheat of 210 F with max interpass of 400 f. Thanks for your help, need to get this done.
 
Probably too late, but...

Most of the SAW PQRs I see are in the 30-70 kJ/in range.

Your current seems really high, and your travel speed seems really low. But D1.5 doesn't have actual HI restrictions. It just is silent on HI below and above the ranges shown in the heat input tables in Clause 12, which means you need to work out with your (apparently as-yet nonexistent) client how they want to handle those heat inputs.

Remember that you should be trying to keep the passes consistent (in terms of A, V, ipm) within the test plate. It's understood that you might have to do something different for the root, but that shouldn't count as your max HI; you should consider what you used for the bulk of the test weld.

Hg

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