European Weld Callouts - Confused with the "/C" and the "a2" portions

[Emmyd]

Hi Covers!

I need some help with some European weld callouts. I used to have a link that was very good at explaining the callouts, but I no longer have it and can't find it with searches.

I've attached a photo of the part in question - it is a flat plate with a large nut that is to be welded - 2 callouts are listed for the same feature: a fillet weld and a projection weld. I know the symbols for the fillet & projection weld, and the "23" & "141". I'm more confused with the "/C" and the "a2" portions. Can someone please help?

Thanks in advance!
Em

 

[Miner]

re: European Weld Callouts - Confused with the "/C" and the "a2" portions

I think I found the a2 reference in this link as referring to a dimension for the fillet.

The 23/C and 141/C in the prior link as well as this link refer to 23 = projection weld, 141 = TIG weld and the /C as the welding class. I could not find any details on the welding class.

 

[Emmyd]

re: European Weld Callouts - Confused with the "/C" and the "a2" portions

Thanks, Miner. I did find the classes in my search - the C class is for non critical welds.

I appreciate the feedback!
Em

 

[Marc]

Thanks, Miner. I did find the classes in my search

Where did you find them?

 

[Emmyd]

Where did you find them?

Here's where I found the classifications.
Definition of Class A,B,C Welds / General Welding Discussions / Weekend Warriors Welding Forum

 

[Marc]

Thanks - That may help folks with future welding questions.

 

[Al Rosen]

I'd be careful accepting those definitions, without reference to the primary source. Here is another explanation for welding class.

Weld Classifications

One of the most comprehensive sources for designing welded structures is British Standard BS 7608 "Code of practice for Fatigue design and assessment of steel structures". It provides standard SN curves for welds.

The curves shown above are valid for structural steel welds.

Look at

eFatigue - Cookies Required

 

[Emmyd]

I'd be careful accepting those definitions, without reference to the primary source.

Good point. I can definitely see the difference between structural welds and the kind of weld I asked about. This particular weld on the picture I shared is not a critical weld - usually we only projection weld nuts like this as the function is to only hold the nut long enough to torque the mating bolt in place. The unusual part of this print is that it calls out 2 different welding methods for the same nut.
I do agree that it is always a good thing to check the primary source.

Thanks!