direction of travel

By Lawrence (*****)

Date 12-06-2010 22:51

Do you have a downhill PQR ?

Not that I think it's worth burning alot of my own calories trying to qualify a welder that can't follow a wps.

By azphiks (*)

Date 12-06-2010 23:16 Edited 12-06-2010 23:20

As I stated above, our WPS is up / down for F3 welding only. However, the welder in question is not qualified on his cert / ticket to weld downhill. He has passed his qualifying weld on this job uphill, just as his WQR requires(he brought this ticket to the job and was req'd).

By Shane Feder (****)

Date 12-07-2010 04:03

Azphiks,
Firstly, a big mistake writing a WPS with uphill or downhill (It is perfectly legal but totally impractical).
It is supposed to be a guideline to the welder.
If you want your production welds uphill then write a WPS that reflects uphill.
If you want your production welds downhill then write a WPS that reflects downhill.
How can you possibly write a WPS with useful information if you are trying to cover two totally different techniques on one document.
What amperage range is shown on the WPS ?
There is a huge difference in amps between uphill and downhill, did the welder comply with the amps shown on the WPS ?
Personally, I would cut the weld out as it has been performed by an unqualified welder.
Regards,
Shane

By azphiks (*)

Date 12-07-2010 12:34

Much appreciated. This is my first job NOT welding and I agree with everything you say. When the time comes for me to write my first procedure (surely a few years away) I will remember this post.

By js55

Date 12-07-2010 13:43 Edited 12-07-2010 13:49

There is no need to cut the weld out. Write an NCR within your system. Disposition as requiring RT, or even UT. Shoot it and read it to Section IX. It is no different than taking advantage of qualification through production welds except for the NCR.
If you have the procedure written for both up and down, which I do all the time, then you haven't violated your procedure.
Keep in mind, you did not have a system failure. Your system caught the non conformance. Now treat it as such. You will NEVER have a system wherein people do not make mistakes. Redundancy is the trick. These are exactly the types of things that an NCR/CAR system is for.

By dbigkahunna (****)

Date 12-13-2010 12:37

Shane, I have to disagree with you on single purpose procedures. 5P procedures are commonly written as up and down as direction of travel. For the PQR direction of travel is not a essential variable. This lessens the number of procedures that need to be qualified.
As the inspector the job is to accept or reject the weld. In this case the weld should be rejected as it was made by a unqualified welder.
Disposition of the weld is another matter. As just the inspector, using the weld as a qualification weld is up to the fabricator's QC process. Depending on the fabricator and end user's specifications, the weld may need to be removed.
Coming in after a weld is made and saying the weld is a welder qualification weld raises some issues.
Did THAT welder make the weld
What were the parameters during the welding and were they within the PQR?
Who is going to sign the welder qualification documents. I have a rule, if I did not see the test weld made by a specific inspector, I am not going to sign the papers.
Most codes require all welds to be made by qualified welders. Welds made by unqualified welders are to be removed.
You cant go wrong in this business sticking to code and specifications.

By Shane Feder (****)

Date 12-14-2010 00:33

dbigkahunna,
I agree with the majority of your post but cannot get my head around the single purpose procedure.
What is wrong with qualifying one PQR and writing two WPSs off it - one up and one down ?
As you are well aware there are huge differences in amps, volts, travel speed etc between the two directions of travel and while they are non essential variables we are still supposed to be offering guidelines to the welders who are using the WPSs.

Jeff,
My comment about cutting the weld out was purely my personal opinion.
A lot of jobs I have been on in the past the welder would have been "out the gate".
An example
Worked on a US$ 1 billion dollar Methanol Plant in the early 1970s (a lot of money in those days) for Bechtel.
We were welding 54" Cooling Water lines and it was vertical up all the way with 6010s.
One contractor had a large amount of very good "stovies" who had just finished the pipeline bringing the gas ashore to the refinery.
For some reason a lot of them struggled with the vertical up even though they were proficient with the vertical down.
Everyone knew that vertical down was not allowed on site but the welders continued to do it whenever the inspectors weren't looking.
Bechtel got wind of what was going on and instructed the contractor to stop all work immediately.
All non completed welds were checked for direction of travel (capping runs were always vertical up) and 13 welders were sacked on the spot.

A welder cannot choose his direction of travel just because the WPS allows it.
He/she is governed by the ranges noted on their Welder Qualification certificate.
If I have a welder who cannot understand the range of their qualification or blatantly ignores their range of qualification then they are of no use to me.
Cutting the weld out as an example would be a minimum - "alternative employment" may be required dependent on circumstances.
Regards,
Shane

By dbigkahunna (****)

Date 12-14-2010 20:27

Shane, it comes down to cost. While you can write the PQR, the WPS has to be done. You have material cost, welder time, witness time and testing laboratory cost. If you work for a company where the $3-4K per WPS is of no consequence then single purpose WPS are fine. And as code allows the direction of travel not to be considered a essential variable that is what we have to live with.
I never understood how they came up with allowing a procedure to be qualified with direction no being considered an essential variable but the welding test it is.
I understand the procedure is to qualify the materials, welding electrodes and process where it welder test is to judge the ability to deposit sound welds.

By Shane Feder (****)

Date 12-14-2010 23:47

dbigkahunna,
Now you have got me completely confused.
There are no additional costs.

Weld a PQR coupon using E6010 vertical up root and E7018 vertical up fill & cap.
Perform all required tests.
Write the PQR based on all the information gathered during welding and testing of the coupon.
Call it PQR SMAW - F3/F4 - 001

Now write a WPS for vertical up welding based on all the information contained in the PQR.
Call it WPS SMAW - F3/F4 - 001

Now write a second WPS that is exactly the same except direction of travel for root run is vertical down.
Base the amps, volts and travel speed on a combination of manufacturers recommendations and your past experience / knowledge.
Call it WPS SMAW - F3/F4 - 002

Both WPSs reference PQR SMAW - F3/F4 - 001

If you give a welder a WPS referencing both up and down there is a possibility they will choose what they want to do (as noted in the OP) but if you give the welder a WPS with either vertical up root or vertical down root there is no possibility of misunderstanding.
Regards,
Shane