Tank Repair

[MER3]

I have an 10000 gallon above ground oil storage tank that was imploded due to operator error/ vent abuse. The vent was intentionally clogged by someone trying to do a good deed. Pumping it out caused it to implode. Long story short the tank is now crushed inwards pretty badly.

Before I even get involved with trying to suggest repair solutions, what are the legalities of repairing an oil tank? Are there codes out there that guide on tank repair/ testing of the welds that we'd have to follow? Does the tank have to be brought up to current regulations as far as containment and such? The tank is from the 70s.

Thanks

 

[bimr]

Suggest you post a picture.

The code covering the tank repairs will be whatever code that was used to construct the tank.

The tank system should have already been brought up to date with the containment regulations.

 

[MER3]

I don't have a picture right now. They are already beating the dents out and making it round again. Being that this tank was built in the late 70s, what code was it probably constructed to?

 

[MER3]

Also, the deflection inwards was on the order of 1-3 inches at most at random spots around the tank.

 

[bimr]

Probably was built to API 650. It should have a label on it.

https://law.resource.org/pub/us/cfr/ibr/002/api.650.2007.pdf

https://law.resource.org/pub/us/cfr/ibr/002/api.653.2003.pdf

"Damaged parts shall be repaired or replaced. Prior to tak­ing this action, the cause of the damage shall be identified and corrected. Buckled parts shall be replaced, not straightened. Torn seal fabric shall be replaced."

 

[LittleInch]

10000 gallons sounds like a 30 x 9 horizontal cylindrical tank? These tanks often not designed to a code only industrial standards.

At 40 years old I think its done its job. Scrap it. Anything else is simply asking for a catadioptric rupture. If its in a bund and you can allow it to fail without further damage then you might get away with, but there isn't anyone on the planet who will certify it or guarantee it.[ignore][/ignore]

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[MER3]

It's a 20' tall vertical tank. We found the label but it has no useful information as far as spec goes. It is registered with our state's DEQ.

My gut instinct is to scrap it also, but the people who asked me want to reuse it. I am trying to find a way that lets them do that without just saying "Because we said so".

 

[LittleInch]

What's in this tank? Does kit have a full containment bund? What happens if it falls?

Basically plate that has yielded should not be yielded back and work hardened even more. Hence buckled plate should be cut out and replaced. Do that in more than one location and the cost sky rockets. Get a replacement cost as comparison.

The owners can ignore you, but I would walk from this one if they do. For too much risk.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[MER3]

There is a containment bund (I assume you refer to what I have been calling the "dike").

As far as contents, it's just used oil with water mixed in. Waste that eventually gets pumped out and hauled off site.

I am waiting for the DEQ to tell me what we have to do to get them to bless off on it. I expect they are going to give me a laundry list of stuff. And after all that work we are going to end up with an old dented tank. So I am going to present the replace and repair options just like that to them.

 

[LittleInch]

I'd still love to see a photo to get an idea of how dented it is....

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[bimr]

If the tank was constructed to a code, the information should be stated on the nameplate.

 

[Duwe6]

No nameplate is not uncommon. It is probably built "in the manner of" API-12F or 650.

You have to cut out all the creases and replace with new material, following the old seam-to-new seam tolerances of 653. Then finish pulling/beating out the worst of the dents. And yes, it will forevermore be an ugly, dented tank. "Repair" seems to be a knee-jerk reaction from the current crop of money managers. And I'll bet that at 20-ft, the repair cost will exceed half the cost to replace with s new tank. Might want to remind the penny-pinchers that you have a huge potential liability $$$$ if the repaired tank fails. Mixed waste oils plus water = Haz-Mat waste in the USA. If it escapes the berm, the liability could reach $10MM.

 

[MER3]

Does API-653 apply to 10000 gallon tanks? It seems that the rules relax a little bit once you drop below 25000.

 

[bimr]

API standards are published to facilitate the broad availability of proven, sound engineering and operating practices. These standards are not intended to obviate the need for applying sound engineering judgment regarding when and where these standards should be utilized. The formulation and publication of API standards is not intended in any way to inhibit anyone from using any other practices.