Qualification on pipe sizes

By jarsanb (***)

Date 10-27-2014 17:16

You won't find it 1104. That is usually in contract documents. Now, depending on how the welding procedure was written, it may be necessary to use two welders to maintain minimum time between passes to avoid a preheat maintenance process, which are required variables in the WPS to API 1104 (minimum time lapse between root and first fill pass - essential variable, minimum time lapse between subsequent passes - nonessential, but still needs to be followed unless a written revision proceeds a deviation). Or, if the procedure was written with longer time periods, one welder can handle the requirements unless it's in the contract or job specifications, many times pushed by union labor.

By jarsanb (***)

Date 10-27-2014 17:25

Now, as bizarre as this is about to sound, we had an engineer not allow SAW procedures from a prefab contractor because the contract bid specifications listed "two welders" criteria for diameters 12" and larger for that project....I guess you could say that to allow this would be an unfair advantage to the winning bidder over the other contractors - I guess.

By Tigman214 Date 10-27-2014 18:50

Thanks I have been searching everywhere for this.

By Stringer (***)

Date 10-28-2014 23:41

With so little change to 1104 I don't see why this can't be in the standard. The procedures are so well established the men and equipment should be in Jurassic Park.

By Superflux (****)

Date 10-29-2014 00:49

Actually the API 1104 Standard has more than doubled in size in the past 28 years.

By CWI7611 (**)

Date 10-30-2014 14:10

I now exactly what you are saying having, more or less, worked right down the hall from you or, in reality, across the state. And I know exactly what "specification" you refer to. I had this very same conversation at different times with different engineers over 37 years. I guess that's what you get when you apply the literal word to the interpretation and in some cases it must be. The "Pipeline Construction Specification" does say at least two welders are required for 12" and above. Having said that, I don't see a lot of SAW welding going on in cross country construction. What was always needed was a "Fabricated Piping and Assembly Specification" but then you can write several more specifications to go along with that too. There was one written for shop fabricated assemblies but it was decided after many years without being updated it wasn't needed any more. It was an engineering document not a construction document. Back then we had a Construction Section but the documents were all engineering documents. I guess that we should have felt privileged, we, as just field minions were allowed to comment on them.

What you will continue to learn, and you are wise already, is that you are not an engineer therefore you are not well enough educated to make those kinds of decisions. Unfortunately people who are not experienced do get to make those decisions. As you know I fought the battle many years. It's hard and frustrating and sometimes you just have to walk away shaking your head and be content with the fact that these people can waste money any way they want to.

You can bet that the other contractors were and probably are using SAW procedures they just didn't reference or ask the question about using one welder for SAW welding. Let's face it, in fabrication, as you know, many of the fit-ups are made by one or two welders or a welder and fitter and tacked in place then at some time put on a manipulator and the root bead and HP is put in by one welder, sometimes two, but not often. I guess the thing to do is find that particular job, if it went to another contractor, and see if the welds were finished with SAW, probably a good indication that only one welder was used for F & C and then reject all the welds because the procedure using two welder were not used. Most likely for F&C on the mainline only one welder was used. Maybe the specification has a statement that "...for all root beads and hot passes two welders shall be used for pipe diameters twelve inches and above".... Remember "Common sense isn't all that common any more". With all their education it doesn't necessary mean they are smart. You will get like I was, you know you are right and you will fight the battle every time but then you learn that beating your head against the wall time after time hurts. Remember the discussion about the frequency of the multiple qualification test? There were five people there, I knew I couldn't win. After two breaks to privately discuss the issue a compromise of every other year was agreed upon. So much for the corporate code of ethics. I had bled enough already and I could live with the slow drip for a few more years.

By the way, getting better, but that's what I thought the other two times too.

By dbigkahunna (****)

Date 10-29-2014 00:19

API 1104 is not a code. Cant find anywhere on ot where it states it is.
ASME B31.4 (Liquids) and ASME B13.8 (Gas) are the code documents. Regulated pipelines fall under 49CFR Part 192 for natural gas and CFR Part 195 for liquids refer to the ASME Codes and the API standard 1104.
IT\t is up to the pipeline operator and contractor to develop the welding procedures to comply with the standard and regulations.
If a operator establishes a procedure requiring 2 welders for pipe sizes over 12 inches then that is what is required. There is a reason you want 2 welders on pipe over 12 inches and as the pipe diameters get larger 4 or even 6 per weld.
I do not understand the Jurassic Park comment. Maybe living on the wind swept plains of the Permian Basin I have missed a new earth shattering development in pipeline construction. The process of cross country pipelining has changed little from the late 1930's. You can bet your last dollar if pipeliners had found a way to lay pipe faster and easier it would happen.
There are better trenchers, directional boring equipment, pipelayers, pipe, coating and welding process'. But is still comes down the front end, firing line and tie-in's. The most common welding process is SMAW, down hand or downhill. The process proves itself every day. To get 132 welds (one mile) with a rejection rate of less than 1% day in and day out with 10 welders on 12 inch pipe takes a highly coordinated and skilled group. On a good day this could get stretched to 150 welds a day. That comes to 15 welds a day per welder. What new modern process is faster with the level of quality on most cross country process.
And for all the hundreds of thousands of welds put in with this Jurassic process the #1 cause of pipeline failures is corrosion, #2 is third party strikes. Weld failures on pipelines are mostly from Pre 70 ERW seam failures. Not from field welds.

By lo-hi

Date 10-29-2014 10:12

Worked on chip powered power plants in the 80s. The cooling water supply and return were sch 40 36". Weld temps weren't critical, so after fit up, one welder per joint. 5p root, lo-hy all the way out, nothing bigger than 1/8. With a good fit you could get two on a twelve hour day. Through in a belled out reducing t and it was one a day. Sometimes it would been nice to have a helper just to talk to. Perley

By js55

Date 10-29-2014 15:15

While I have seen many specifications requiring multiple welders on diameters larger than, generally 12", and I do see the logic of it though there are two issues that might be worth considering.
First, for shop applications there is little sense in multiple welders since, at least for rolled applications SAW will be the process of choice and multiple welders is absurd. I would expect this to be an exception for double joint racks, though I do not know this as fact. Even fixed welds, welded with FCAW, can be faster than an SMAW brother-in-law application.
Second, I cannot see either the mechanical or metallurgical reasoning for such requirements. And I have yet to encounter anybody that can provide such.