fillet weld symbol with no size specified

Date 02-28-2008 22:31

the prints are the directions for the personnel to properly do their job. how will your welders know what size to weld and how will your inspectors inspect if they don't know what the size req's are? in a drastic situation you could have one welder laying down 1/4" fillets because he wants to make sure it holds and on the other side of the shop you have a welder laying down 1/8" fillets because he thinks that is all it "really" needs. i would find it an economical decision to size the welds appropriately, simply because you can lose a lot of money by letting oversized welds wreak havoc and accepted as the norm. just some food for thought, hope it helps

regards,
JJ

By R McLead (**)

Date 02-28-2008 23:55

Thanks for your reply the reason I asked the question our company has recently mandated refresher classes on weld symbols and how they are used in welding symbols. Other people attending these classes said that they were told this exception was acceptable. The class I was in attendance in I did not hear this statement. I have just started studying for the CWI exam and I could not find any thing that allowed this exception to have no size used with fillet weld symbol. I understand in groove welds no size means total joint penetration of weld but every thing I have read says noting of this in fillet welds and I have never heard this before.

Thanks
R McLead

By Joseph P. Kane (****)

Date 02-29-2008 02:54

Many times the Structural Design Drawings will have the fillet weld symbol without a size designated. The detailer then makes up the detail drawings (Shop Drawings)and sizes the weld to the AISC Standard.

Sometimes detailers are too lazy to re-draw the drawings and you get stuck with the question. The Engineer of Record doesn't catch it, and you get stuck with the question.

By dmilesdot (**)

Date 02-29-2008 12:21

The only time the size can be left off of the symbol is if it is covered in the drawing notes. AWS 2.4 states that dimensions of fillet welds covered by drawing notes need not be repeated on the welding symbols.....
Dave

By Tommyjoking (****)

Date 02-29-2008 12:53

From my point of view as a welder: It is much preferable whither ndt, nt or simply a visual inspection.....A fillet size in width, throat penetration, and heights is calculable by a hard spec. Simply a statement like all welds are subject to ASTM spec # blah blah blah.....THAT is much preferable to ambiguity. Call out a hard mensurable spec...everyone will much prefer that to a visual ambiguity ....the more you can measure the more surefooted you caN PROCEED....and your workforce will appreciate you for that over ambiguity any day of the week.

just my $.02

Tommy

By Kix

Date 02-29-2008 13:12

If you have a weld symbol with a size called out on the arrow-side then the other-side does not need a size called out unless you want it a different size then the arrow-side. It's more user friendly if they put a size on both side though.

By MDG Custom Weld (***)

Date 02-29-2008 15:32 Edited 02-29-2008 16:36

I see this on almost every print I get from the auto manufactures. They just have the fillet symbol and that's it. The way these must be figured is by going to the OEM "welding spec". Because the material used on most vehicles is light gage (relatively speaking), and each manufacture has their own welding spec, the material thickness being welded dictates the fillet weld size. They have a "governing metal thickness" which is the thinnest of the pieces being welded. The fillet size is then based on a % of that GMT, usually 70-90%.

I now see many auto suppliers doing the same thing and referencing the OEM weld spec in the print notes.

By R McLead (**)

Date 02-29-2008 15:54

I want to thank every one for there input and the statement in this class was supposed to have been made concerning 12ga or smaller sheet metal. I work for an OEM equipment manufacture and these sheet metal components are used as covers for mechanical components.

By Bob Garner (***)

Date 02-29-2008 16:06

I was taught to always call out the size of a fillet weld unless it was designated as a seal weld.

Bob G.

By 803056

Date 02-29-2008 16:06

Many shops have developed "Standard Shop Practices" where the minimum size of fillet welds are established based on the thickness of the thinner of the members being joined. In the case of a sheet metal shop where light gauge metals are welded, the size of the fillet weld is typically equal to the thickness of the material being joined.

Other companies modify the basic AWS welding symbols to suit the particular conditions of their industry or company. Aerospace companies I've worked with as well as a few pressure vessel fabricators have developed their own "standard symbols" for use by their in-house workers. In some cases they are actually "published" so that everyone can interpret them the same way. This is fine for in-house work, but it creates nothing short of havoc when they try to subcontractor work to outside vendors.

When I went to work for one company I told them their welding symbols didn't follow AWS conventions. The response was that it was alright because everyone in the company knew what they meant. I said it would be a problem if we were to subcontract any work, but the response was, "We don't subcontract any of our work." Guess what, within a year they were trying to subcontract some of their overload and several of the vendors returned the bid packages unopened. When I asked why, their response was, "We've seen your drawings before and we won't even bid based on the information in your drawings, they are incomplete, the welding symbols are wrong, and the dimensioning system you use doesn't provide use with the information we need or they are missing altogether. Hum, just what I had said.

I attached a sketch of an example of a nonstandard welding symbol that I've seen used by several designers. Most people can interpret it, but it is not the normal way of specifying lengths of welds.

Best regards - Al

Attachment: Example-NonstandardFilletWeld29-Feb-08.wmf (167k)

Attachment: 586Example-NonstandardFilletWeld29-Feb-08.wmf (167k)

By jrw159

Date 02-29-2008 18:21

This is correct, the size need not be repetitivly called out. There must however be a callout in the drawing notes that states all typical fillet welds to be, just throwing a size out, 1/4" inch.

By R McLead (**)

Date 03-01-2008 01:04

Thanks everyone you have confirmed what I had thought that you couldn't use a fillet weld symbol in a welding symbol with no size unless it is controlled on the drawing with a detail, note or etcetera.

Thankfully
R McLead