WELDING FITTINGS AND WALLS OF TANK

[imagineers]

Ok so I have a tank I am getting made in China. Several fittings on the endplate. End plate sheet thickness is stainless 304 2mm thick. as you can see the model shows the endplate butt welded up against the other two components sheet on top and lower bent sheet. China is wanting to increase the end plate thickness to 5mm ad add chamfers aroud all edges for a weld. Now I had this made locally (Canada), and they made it exactly as you see it with the 2mm sheet metal and butt welding the sheets as you see it. I guess the question is, is this overkill to make a 5mm plate to weld the other sheets to to complete the tank. and is how I have it modeled the way they would normally weld and cut the metal to create the tank? The shape is needed because of space restrictions. The second image is what they suggest.

 

[imagineers]

second pic

 

[EdStainless]

are the fittings welded in with full penetration welds?
If so then that gets tougher with 5mm.
Sounds like they don't want to form and cut accurately enough to use 2mm for the end plate.
If the weight doesn't matter to you and the cost is the same then I would let them.
How do you inspect the welds?????

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P.E. Metallurgy, Plymouth Tube

 

[imagineers]

""3. ALL WELDS TO BE VISUALLY INSPECTED IN ACCORDANCE WITH AWS D1.1/D1.1M: 2010
SUBJECT TO MAGNETIC PARTICLE INSPECTION TO ASTM E709-14.
OR DYE PENETRANT TESTING TO ASTM E1417/E1417M UNLESS OTHERWISE STATED.""

Here is how I am doing it now, with the 2MM sheet metal. We have made this tank before locally without edplate distortion but like I said China mentioned they are concerend about it and want to do all the extra work in, increasing plate thickness, chamfering, and creating locating features on the endplate instead of just laser cut sheet and weld.

 

[racookpe1978]

If the Chinese fabricator is recommending a thicker plate, it is because they do not believe they will produce a satisfactory product FOR YOU with their people, their training and their current abilities.

What is the reason you are resisting getting a thicker wall tank bottom prep'ed with what appears to be a more reliable joint?

 

[imagineers]

Cost has incresaed significantly because of the prep involved and the thicker plate. I guess the thing is we have made these locally with the current design without the prep work and thicker plate etc. But I see your point that they want to create a reliable weld based off their current skillset. It's just adding process to something unnecessary here I guess.

 

[metengr]

From what you have stated, I would stay with the Canadian supplier because of cost and experience.