Dome panel patching

[prashanth5723]

Hi all
one side of a triangular dome panel is short in length. If we need to patch up that dome panel to make up for it original length which process is better? MIG welding or riveting? Kindly share your ideas. Thanks in advance.

 

[IFRs]

MIG is tough on that thin metal. Mechanical joints leak. Can you make a new larger one-piece panel or get one from the manufacturer? How can it be short? Was it an error in the shop? Is it just one? How do you plan to make the edge bends (assuming there are bends that are laid into grooves in the beam extrusion)?

 

[JStephen]

Makes me wonder if somebody didn't trim one that was too big elsewhere on the roof!

 

[prashanth5723]

@IFR. Totally 8 panels are short in length. there is no misalignment in the nodes as all other panels fit perfectly.

 

[IFRs]

Please help us understand what is short. Do the panels fit in the beams on all three sides but one corner does not reach the node cover? Do two sides fit the beams and the third side is parallel to its beam but is short by some distance (how much)? If one side of a triangle changes length and the other two sides remain the same, then two angles will change and in the case of a dome, only one edge will fit on its beam.

Is this a large dome with 8 pie segments?
Are there only 8 of these triangles on the whole dome?

What has the manufacturer told you?

Is the material 0.050" thick 3003-H16?

Are the edges of the panels step-bent ( send a picture or diagram )?

You can certainly MIG weld 0.050" thick aluminum - we weld about 1,400 feet every day in our shops. But, it takes good setup, careful control and allowance for expansion and shrinkage, proper equipment, etc. We also TIG weld similar materials but I would not recommend it for a number of reasons.

Not the least of your problems is how your modified panel will meet the API standard for the design loads of 60 psf uniform and 250 pound concentrated not to mention the clause "G.4.2.3.1 Roof panels shall be of one-piece aluminum sheet" and if your customer will accept the repairs.