75% partial penetration weld 3

[hm5k]

On drawing at column splice connection weld represent as partial penetration weld with single bevel groove with 75%.

please advice, do we need to provide column flange preparation up to 75% thickness of total flange thickness. e.g. W12x40 have 1/2" thick flange so we need to provide 3/8" prep (75% of 1/2") to flange so 1/8" will be root face in that case.

 

[gtaw]

Not to be rude, but I have to assume you are working on a structural steel frame. That being the case, you should be using AISC as the basis of your design and AWS D1.1 for welding. I further assume you have access to both references. If you don't, how can you possibly comply with the requirements of either code?

Due to the nature of the question I assume you are working in the capacity of a designer or detailer. AS a professional or working in the capacity of a professional, you need to have a copy of the appropriate standards for materials, welding symbols, etc. As a professional, you need the tools of your trades just as a mechanic or welder does.

Best regards - Al

 

[hm5k]

Thanks you for your response Al,

Yes this question in the point of view of detailer to represent this weld on shop drawings.
structural engineer represent weld as i mentioned, referring to AISC & AWS this kind of weld not represented.

I hope you can help me on this weld.

thanks

 

[gtaw]

So, the design engineer didn't follow the generally accepted protocol of the applicable welding code. When in doubt, direct the question to the person responsible.

It doesn't matter what profession we look at. 10% would be better off looking for work elsewhere. They don't do or can't do their job. They would rather pass the responsibility to someone else. Most enter politics at some point.

80% do enough to get by and hold on to their jobs.

10% excel by going the extra mile.

OK, I've stirred up the mud, flung stones in the direction of the glass house, in general vented my frustration. For that I apologize.

The truth of the matter is, the detail you included isn't the generally accepted way of specifying the weld size. The Engineer is suppose to specify the required weld size (joint penetration) per AWS D1.1. The Engineer does not have to specify the groove type, groove angle, etc., but the weld size is a requirement. That shouldn't be too difficult since the Engineer did specify the size of the column which means he must know the forces on the connection and thus the weld size.

Clearly, it is beyond the Engineer's capability or maybe simply he or she is too lazy to do the job.

As the fabricator's detailer, you can select from a number of prequalified joint details included in Figure 3.3 of AWS D1.1/D1.1M Structural Welding Code/Steel or a different D1.X structural welding code if applicable.

Generally, the weld size for a bevel groove with a groove angle between 60 degrees and 45 degrees is 1/8 inch less than the depth of the bevel. Again, check the details included in figure 3.3 for the specifics. The generic welding symbol is included. All you have to do is fill in the values required by the welding symbol, i.e., groove angle, bevel depth, etc.

Best regards - Al

 

[hm5k]

This is very helpful to me

Thanks you Al

 

[Duwe6]

". . .you can select from a number of prequalified joint details included in Figure 3.3 of AWS D1.1/D1.1M Structural Welding Code/Steel. . . "
"Again, check the details included in figure 3.3 for the specifics."

What gtaw said. You are never wrong when using the standard joint designs out of D1.1.
When somebody starts making up symbols and sizing details on welds, it is the same as him/her making up a new language -- the rest of us are unable to communicate with them.

The other thing the knotheaded pseudo-eng. left out is whether there is to be any NDT required, to verify fusion/quality. The web weld is a full-penn splice [typically UT'd], and unless the CWI of record saw the fitups on the flange welds, I'd have the flange welds UT'd to verify depth of penn, and acceptable quality.

 

[Tmoose]

What is the ranking of knothead vs knucklehead ?

 

[racookpe1978]

Sure, you could assign (require) a 75% partial penetration weld across the web and flanges of your beam on that dwg .....

As long as you also only assume a 75% (or less!!) strength of the flange and web of your beam at that point for your strength calculations.

 

[WillisV]

This is a trickier question that it appears and should be asked in an RFI. Based on my experience, generally structural engineers providing a detail like that sometimes mean that they want the weld to develop 75% of the flange strength. Due to the reduction factors associated with PJPs in tension you actually need to provide a larger effective throat than 75% to make that happen, and with thinner flanges it is sometimes not possible without providing an actual CJP:

For your example (in 14th Ed. LRFD Gr50 Steel E70XX) - W12x40 has a flange strength of Phi*bf*tf*Fy = 186.6 kips. Strength of PJP = phi*0.6*Fexx*bf*(groove-1/8 for typical SMAW) = 0.8*0.6*70*bf*(groove depth - 1/8") from Tables J2.1 and J2.5 for PJPs with tension normal to weld axis. Setting the two equal to each other gives a groove depth exceeding the flange thickness - therefore you would need a CJP.

Now sometimes the engineer actually did mean to just provide a groove depth of 75% of the thickness of the flange and they had already done the above calc etc...or it is just a compression member and then who cares...

 

[hm5k]

Thanks you to all for your comment that help me lot.

I already asked RFI on the same to engineers, i will share response once received.

 

[hm5k]

Finally i got response from engineer,

they consider 75% of thickness of flange.

thanks to all

 

[gtaw]

Thanks for the up date. It is nice to hear what the final resolution is.

Best regards - Al