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@weldstan - thanks for that advice! I hadn't thought of looking at the material spec for allowances on repair. One thing that jumps out to me is that SA-480(21) allows for weld repair of the base material up to 1/3 of the thickness. This isn't applicable to our issue because we exceed that...

When NDT is required, it is done. Scheduling issues can make it non-ideal so we only do it when necessary. That said, if it’s not required, we don’t do it. The gist of my question was whether there is another applicable section other than UW-42. If there’s not so be it. The code rules are long...

The vessel hasn’t been put into service. It hasn’t even been stamped yet - it’s still being manufactured. The issue with NDT, is that all NDT is contracted out and scheduling is very difficult. We were hoping to find a way to do this without NDT.

Hi All - We're trying to settle a debate internally. We have a Section VIII Div 1 vessel where the shell wall was hit by a cutting wheel while removing a weld. The shell wall is 1/4" thick and made of formed plate; the gouge groove is about 1/8" deep x 1/8" wide and 1" long (very smooth/regular...

To further add onto this, since you are using ASME VIII-2 Part 5 but the code of construction is VIII-1, you need to limit yourself the to material yield stresses allowed by VIII-1.

@Idan - there have been times that I thought I was right but turned out there was something I was missing. The opposite has been true too. If you post the details, perhaps this community can either help illustrate the AI's views or reaffirm your view... or go to the AIA.

Thanks Ed! Do you think salt spray tests or boiling in salt water would be appropriate for pitting or generalized chloride corrosion?

First, thanks for the feedback! Ed - you raise some good questions. I'm sorry but I don't really know how to answer the failure mode question. In terms of present conditions, we see may visual evidence of corrosion after anywhere from 7-15 years in service depending on field conditions. The...

Hello, My company has an application where we use welded 316L plate at elevated temperatures (250F-300F) in a steam environment with chlorides present. Historically, we have seen issues with pitting, SCC and generalized chloride corrosion in the heat affected zone of the welds. We are...

We want to switch because we’re a production shop and GTAW is too slow.

Thanks Ed! Would that test also show evidence of either sensitization or chloride stress corrosion cracking? Edit: Sorry, just read through the test standard and it's clearly only meant for pitting. I'll give that one a go for pitting. I'd welcome suggestions for other corrosion modes too.

I'm planning on welding up test pieces to using both AR-O2 versus AR-CO2. I'd like to send them out to see if either one is more resistant to corrosion. Does anyone have any recommendations of appropriate tests to determine resistance to pitting and chloride corrosion? Given that the differences...

I agree, we've used He-AR-CO2 90/7.5/2.5 Tri-Mix in the past but He is VERY expensive. Also, as far as I know, Tri-Mix is not appropriate for spray transfer. We've only every used Tri-Mix for short circuit transfer. Our welders and the literature I've read seem to agree with this assessment. In...

Thanks for your reply, Ed. From all the information I've gathered, it seems that He is not advisable for spray transfer and it's predominantly used for short-circuit only. We've used tri-mix in the past for short circuit transfer but haven't tried that for pulse spray. Do you use an He mix for...

I've done a fair number of large rectanglar vessels at much higher pressures and would very strongly encourage you to avoid welding the plates at the corners. Between strength, fatigue, distortion and other manufacturing issues, you are asking for a world of hurt. Not to mention, what's you NDE...

We have a single side weld v-groove joint made from 1/4" thick 316L with backing. It's welded in flat position and we require full penetration. We're looking to change the weld process from GTAW to GMAW. For this joint we're sensitive to both chromium carbide as well as oxide discoloration. We...

For the purpose of this analysis, no it is not.

Thanks for the feedback! I do realize that having the web elements rotated 90deg would make the structure stronger and easier to analyze. Unfortunately, the span is specifically designed as shown for a variety of reasons and other design factors. I completely understand that with the given...

The lower diagram is a (maybe?) simplified way that I was thinking about the upper design. The upper diagram is the actual arrangement.

Hi All, I have a design that I'm trying to analyze by hand calcs before I use numerical methods (FEA). I'm working on beam calculations for max shear/moment so that I have something to validate against an FEA result. The design involves applying pressure to two flat plates that are joined to...