Does weld symbol without field tag explicitly state a shop weld?

[PUEngineer]

The only thing I could find regarding the question was a topic of the discussion in Salmon and Johnson's Steel Structures book. To dictate a shop weld, the authors indicate a note in the tail specifically stating the weld is to be a shop weld...otherwise the weld isn't specificaly stated as one or the other. Does anyone know of a specific AISC or AWS section that discusses this?

Thank you.

 

[BAretired]

As far as I am aware, if the field weld symbol is not used, it is a shop weld. The note in the tail, if used, is describing a process.

BA

 

[JStephen]

"Field welds (welds not made in a shop or at the place of initial construction) shall be specified by adding the field weld symbol"- AWS 2.4-98.

 

[hawkaz]

The standard here is to indicate that the contractor may field weld or shop weld at their own discression. We try not to mandate means and methods unless there is a good reason for it. Since we put this note on the plans, we do not add the field weld symbol in most cases.

 

[nutte]

There's so much variation on how weld symbols are used on contract documents that the intent may not always be clear, despite the rules and general practices that we're supposed to adhere to. The all around symbol is a common culprit, used much more often than it should be.

Lots of engineers will have a general note somewhere that welds should be made in the shop, except where specifically noted as being a field weld.

What's going on in your specific case? You want to make a weld in the field but the drawings don't show it as a field weld?

 

[slickdeals]

There are some welds that absolutely have to be field welded. I mark them with the field weld symbol. Unless it is tagged with the field weld symbol, the contractor has the option to field or shop weld it. 99% of the time, they would rather shop weld it because the shop is geared towards it.

 

[PUEngineer]

I detailed an architectural piece that was bid without questions. The detailer/erector is stating that there are clearance issues for tightening the anchor rods. I've said that field welding the main piece to the base plate is acceptable. Costs associated with the field welding are being thrown around because the drawings don't specifically state that the weld is a field weld. In my opinion, a weld symbol without the field tag is saying that either weld is acceptable.

 

[dik]

The Contractor is responsible for the final installation based on the Construction Documents.

Having said that, a weld that is stipulated as a field weld should be field welded; if it cannot be field welded, there may be a legitimate cause for an Extra to Contract. At the discretion of the EOR, it may be shop welded.

If the weld is not stipulated as a field weld, then it may be either field or shop welded, at the discretion of the Contractor, or sub-trade. If it must be field welded, any extra costs are between the Contractor and sub-contractor to resolve. Be careful that you do not instruct the Contractor that it *must* be field welded unless specifically shown as such...

My 2c, Dik

 

[nutte]

This is an interesting question, and I can't find where it's explicitly addressed. AWS D1.1 states the following in section 2.1.1:

If the Engineer requires specific welds to be performed in the field, they shall be designated in the contract documents.

If you're not requiring that the weld be made in the field, this implies that nothing special is required on your part. If you have no preference over a shop weld or field weld, it would seem to me to be at the contractor's discretion, as means and methods are his responsibility.

The source of the clearance problem may be another area of discussion. Did the contractor select a certain construction sequence that led to this clearance problem? If so, and if more expensive welding results from it, that's his problem, a consequence of the methods he chose previously.

If the detail wasn't constructable, and the weld really could only be made in the field, perhaps it is back on the Engineer to have shown this as a field weld in the first place.

 

[Ron]

To answer your first question...Yes.

To answer your philosophical question...unless you know that a field weld will be detrimental to the structural efficacy of the member or structure, let the contractor decide means and methods. You can do this with a general note on your plans or specifications that if the contractor wants to submit field welding in lieu of shop welding, they may do so and it will be reviewed.

Keep in mind that field welds are often "out of position" and made under environmental conditions that are significantly less controllable than in the shop...so expect that more effort will be required to achieve the same weld quality in the field.

Require all the proper documentation for the welders and procedures, whether field or shop. Require a higher rate of testing for field welds.

 

[JStephen]

If the field weld is made by one party, and the shop weld by a fabricator, then that field mark will also be used as a notation of who is responsible for which part of the work, and the field-extra will be larger than the shop-deduct for the weld.

 

[dcarr82775]

IMO all welds are assumed to be shop welds unless the 'flag' is on the weld calling for a field weld.

 

[PUEngineer]

Well, it sounds like there are varrying opinions as to the answer of the original question. I figured that would be the case.

I'm staying out of the means and methods, BUT the fabricator/erector is basically saying that I spelled out the means and methods of erection by showing a weld without a field tag, which in turn he interprets as a shop weld....hence my original question.

My personal opinion of the situation....it's the very last steel to be erected on a job in an economy where the projects were consistently coming in under budget, so there is probably some money trying to be made here or recouped. Were this not the case, it probably would have been done without any issues.

Thanks again everyone for your thoughts.

 

[HSIII]

My opinion...

flag = field

no flag = workability (shop or field)

Most of the time with no flag, depending on what the welds are for, shop fab wins out over field welding.

 

[dcarr82775]

Just curious, some think no flag means it is the contractor's choice between shop and field. Why ever show a flag at all?

 

[BAretired]

Interesting question. I show the field weld symbol only when it must be a field weld. Otherwise, I want the welds to be shop welded because they have better quality control. If the contractor has reasons why an unflagged weld should be a field weld, he must ask for the consent of the EOR.

BA

 

[nutte]

Dcarr, for one, the AISC Code of Standard Practice requires that the Engineer show flags on welds that he requires be field welded.

I don't buy it that no flag means shop weld only. How do you just show a weld, that can be made in the shop or in the field? Do we have to put comments in the tail of each weld symbol saying "This weld can be made in the shop or in the field"?

 

[PUEngineer]

I guess that was my understanding, a flag says it must be a field weld. No flag, it's sort of a contractors option, but by and large they aren't going to want to field weld because of costs, our of position welds, etc.

Some types of field adjustable connections would be where I would specifically show a field weld.