PQR variables and WPS limits

Date 03-04-2008 16:49

Are you mixing apples and oranges? AWS D1.1 has nothing to do with API 1104 ir other API welding standards that I can think of. Are you asking the question relqative to AWS or to API?

Al

By paul 3

Date 03-04-2008 20:39 Edited 03-04-2008 20:52

the actual amperage used that was written per WPS and on the actual sample used in the test , should be recored on the PQR. your not allowed to falsify documents. only record actual essential varibles used for the procedure,regardless of the code that you are following.

By Matt 2

Date 03-05-2008 02:29 Edited 03-05-2008 03:06

Let me rephrase.I am not trying to mixing apples and oranges. We use D1.1 as our code. The company is API certified for monograming the drawworks and derricks that we put on the oilrigs we build, mainly for the international market.

The question is, if the PQR and the WPS state the actual amperage used during the test then what is the welder allowed as a variable during welding on the weldments. If the answer is "To a value not recommended by the manufacturer" then will the welder be in violation of the WPS since it is not recorded? If it is a violation WHERE should it be put?

The API auditor can review any documents. I am just trying to keep from having any problems when he comes.

I would not falsify any document for anybody.

By James Corbin (**)

Date 03-05-2008 04:33

Even though the SMAW does fall under the manufactures recommendations as listed under Table 4.5, (brand type specific, not all electrodes are created equal and the min max limits will be different) there are other things under table 4.5 that could restrict the final WPS too many to list quickly. (See also 3.7.1 & #30, specific groove #33 or #31 not in section 3 & 3.13.3 #2, Table 4.6 limitations or material not listed under Table 3.2 & 5.3.1.2)

From the limited information it looks like the PQR was done to allow open root CJP welding using a vertical down root, (doubled for thickness to keep the 7018 from burning through) just make sure the usable WPS follows this and the other table 4.5 limits.

Just a thought unless there is something you did not mention

By Kix

Date 03-05-2008 16:59

No just leave it as is and if you are already above or below the manufactures recommended amperage then don't go any more above or below. 95amps for a 3/32 electrode is freekin hot. Why even run that 3/32-rod, just go to a 1/8" rod right after the 6010. Your still legal if you do that because it's only a jump of .03 in size and your allowed to jump .8 in size. If you write another WPS then you can use the manufacture recommendations and then you know not to go above or below that.
There is no essential varibale for amperage except that you can not go above or below the manufactures recomenations. For example, you maufacture says 95-120 amps for an 1/8" 7018. That means you can't go above or below that. Say your PQR was qualified at 110 amps, then you can still turn it up to 120 or down to 95 because there is no % for how much you can go up or down. If you qualified your PQR at 125 amps with the 1/8" 7018 then you can't go any higher then that, but you can go down to 95. The reason you can use 125 amps which would be above the manufactures recomendations is because you qualified it. Ya smellin what i'm cookin here.

By Matt 2

Date 03-05-2008 23:18

OK. here lies the problem. I have contacted Lincoln and ESAB. They are the manufacturers of the rods. This is their recommended range.
Lincoln 5P+ 1/8 65-130 amps.
ESAB Atom Arc 7018 3/32 70-100 amps
" " " 7018 1/8 90-160 amps
We use the 3/32 in the procedure because under D1.1 you can go up 1/32 in rod size, but you can not go down. Therefore if we are welding on thin material, ex. 1/8 or 3/16, we can use them because they are included in the procedure.

So do the variables have to be documented on the PQR or the WPS?

By 803056

Date 03-06-2008 04:21 Edited 03-06-2008 04:30

The welding parameters recorded on the PQR are those actually used to weld the test coupon. In other words, there must be a witness to watch the meters to see what the amperage actually was and record it, likewise the witness records the actual arc voltage, travel speed, etc. All the values recorded have to be the actual values used while actually welding. This can not be accomplished by the welder unless he or she has eyes on the back of their head so they can see the meters while they are welding.

Most welders will utilize a rather narrow range of amperage and arc voltage when they weld the test coupon and those are the values to be recorded on the PQR. For instance, the welders amperage may vary between 135 and 145 amps using 1/8 inch diameter E7018 while the voltage may vary between 23 and 27 volts. Those are the values to be recorded. Likewise for the travel speed for individual weld beads. The travel speed may be 2.5 ipm for the root pass and 5 ipm for the second pass, then 4.3 ipm for the next and so on.

I record the preheat or interpass temperature, amperage, arc voltage, travel speed, etc. for each weld pass in a table at the end of the PQR. Then I list the high and low for each parameter on the PQR. I even include a sketch with the actual groove angle, actual root opening, etc. Then I show the approximate placement and relative thickness of each weld pass and the number of weld beads required to fill the groove. Again, we are discussing the information that is recorded on the PQR. I do not use the form or sample forms include in D1.1 or ASME Section IX. They don't do what I need them to do. I have developed my own forms that better suit my needs.

The welding parameters listed on the WPS can have greater range than that used by the welder when welding the coupon for the PQR. They should be reasonable in that the welder should be able to utilize the full range listed and produce acceptable welds. In other words an amperage range of 0 to 220 amps listed in the WPS is not reasonable for a 1/8 inch diameter E7018. It would be reasonable to list 120 to 150 amps for 1/8 inch diameter E7018 in the WPS. A quick word of caution, different codes have different requirements for the allowable range for each welding parameter, so check the specifics of your welding code.

I hope this addresses your concerns and helps you to better understand the information that is recorded on the PQR and what is listed on the WPS.

Best regards - Al

By Matt 2

Date 03-08-2008 01:50

Thank you Al. That was the answer that I was needing. On the PQR is listed all that you have stated, travel speed, temp, voltage, etc., and we have a sketch of the groove angle and weld placement. The only thing I was needing verified was where to put the variables.

Matt