How to Correct a Leak in a SS 304 Vessel?

I take this as a used tank due to your remarks on posiible corrosion and or chemical hardening.

Assuming that this is a pressure tank and one being ASME. you should be able to trace the material type and thickness to the original manufacturer. Look for the ASME "U" stamp or "R" Stamp. This will also have the national board number as well as a Serial Number Identifier. And contact the original company that fabricated, they would have material tracibilty records on file.

(Sounds like the crack happen on the HAZ)

If its not an ASME vessel, then it gets harder.

Yes it can be repaired. such as using a backer plate with the required weld prep. (cleaning, grinding, ect..) if possible.

Remember what its uses is for. If your tanks is ASME Certified and your not. That could be alot of liability you picking up.

Possibility of cutting a bigger hole seems impossible as you state.

The only possibility remains to weld a patch plate, if still weldable. Select a better material of the tank and replace.

,<weld a patch plate>

If you can--from Inside-pressure side.

If NDT dyes REVEAL SMALL SPREAD- go ahead -just deposit metal with manual stick .

MUKULMAHANT is correct I just finished repairing 2 pressure vessels that were 304 ss I tig welded the crack then patched over the area I had to do it on the outside but they held fine at 100 psi

Sound Advice!

I would recommend you to take a small sample piece, just enough for micro-structure examination by whatever cold means possible from the leaking area and get it examined for microstructure. Hardening of Stainless Steel can occur by impact such as a hammer stroke during fabrication due to spontaneous transformation of Austenite to Martensite structure.

The easy solution is to remove whole of the defective area and reweld with a fresh piece.

Im assuming your crack does not transverse a sealing face?

If the operating temperature isnt too high, I've had sucess with brazing such things.

Awesome, to all of you.

This is why CR4 has become my portal of choice for answers and thought provocation.

Sometimes, early in the A.M., I just post to be included, because I know it will eventually get interesting.

And, as an Inspector type of guy, I cannot re-stress enough the Potential for Liability and the "R" Stamp.

hi dear ,

i think the minor leakage stopped by weld a plat around the leakage if possible welding done by 308l grade material.you try to tig welding process.

Is your company a certified repair facility? NBIC "R" stamp

Welding a doubler on ASME pressure vessel is not an acceptable fix, stress risers may develop around the perimeter.

Remove the defect to sound metal and weld the defects, use NDT to be sure or insert the shell plating.

The SS vessel has developed heat stresses so if you weld, it will develope leak at other place or get enlarged. So, in my opinion, you have to do stress relieving first at the place, where you are welding. So heat it first before welding. Keep in mind not to oxidize or carbonize the area.

You have not given the size and welding rod used for repairing.

If you give more details, Forum members can give better suggestions.

The first thing to do is open a dialogue with the Engineer/Surveyor from the company providing burst/collapse indemnity insurance cover on it, and ask for advice there.