Old Gas Tanker

Date 06-30-2020 19:00

Hello Everyone,

I wanted to get some thoughts on a project that a friend of mine was asking me about, wanting my opinion. He was approached by the town to convert an old gas tanker truck into a brine spreading truck...they spray brine down on dirt roads to keep dust down. Its a rather simple task, however for one request, the old tank is separated into 3 sections, requiring 3 separate access ports to fill the tank. What they are wanting is the have him cut holes into the "dividers" so they can fill the tank with one single port, filling the entire tank.

Being that it is an old GAS tank, it is rather concerning...especially since the cutting will be done on the inside, and not the outside. You can't just fill it with water or inert gas and jump in.

My personal opinion is to tell them tough luck, and have them fill them separately...but if i could get some words of wisdom from you gentlemen, i would greatly appreciate it!

Thank you in advance!

By Steelslinger (**)

Date 06-30-2020 21:24

When was the last time it held 'gas'?

What kind of 'gas' was it?

You can wash it out using appropriate cleaners and it would be safe.

But if its been years since it was used for gas, and it had been left to vent for long enough, I doubt it would be an issue. But taking proper safety precautions this would be a easily doable job.

By Steelslinger (**)

Date 06-30-2020 21:25

You could also use 6" hole saws to cut holes in the dividers depending on thickness of them.

By 803056

Date 06-30-2020 23:54

Old gas truck could be any number of things from I think it hauled gasoline, to I think it transported heating fuel oil, to aviation JP-5 for jet engines, to diesel fuel, honestly, I’m not sure what it hauled.

I have an aversion to welding or cutting on anything that transported petrochemicals unless I have a positive way to know what the petrochemical was and how the tank is going to be cleaned.

Since the tanker has baffles to stop the contents from surging while starting or stopping the truck, any holes in the bulkheads must be such that the effectiveness of the baffles isn't compromised. I suggest using a drill with a hole saw or "rotatory broach" to drill a series of holes that will permit the tank to be filled or drained through one fill or drain port.

What is the tank made of; stainless steel, carbon steel, aluminum? Consider the density of the brine versus the density of the original “oil”. The strength of the tank may not be sufficient for the new fluid. Consider the material of construction and its resistance to corrosion caused by the brine. Oil is lighter than brine and oil isn’t as corrosive as the brine.

Al

By welderbrent (*****)

Date 07-01-2020 00:38

Like, LIKE, Really LIKE.

Al has pretty well stated the case.

Beware any involvement and counsel. It could lead to liability you may not want.

Have a Great Day, Brent

By mwilliams93 (*)

Date 07-01-2020 19:36

Thank you Gentlemen for your wisdom! I feel the same way when it comes to cutting into petrochemicals tanks.

As far as the 'gas', i was told by the gentleman that it was diesel and he also told me that a "Diesel Only" sign is on the tank (not fuel tank for the truck)...sounds promising. As far as how long it was since the last time it held any product...i have no idea. The tank is made out of stainless steel and his original plan was to use a hole saw.

What kind of cleaning agents would be used to clean out the tank? I assume he could add that to the scope of this job.

Appreciate the help!

By 803056

Date 07-01-2020 21:30

I could be wrong, but I believe there are companies that specialize in cleaning tanks with the intent of repurposing them. This isn't a do it yourself project. I'm pretty sure the EPA has some say about how the residue is disposed of.

Al

By Northweldor (***)

Date 07-06-2020 15:28

Many decades ago, during my apprentice period, I worked for a tank construction and repair facility. All tanks coming in for repair were steamed for 24 hrs minimum, and then, cooled and metered for fume concentration before entry for washing down.

Bulkheads between tank compartments were an integral part of tank structure, and were reinforced to prevent flexing between each 500-1000 gallon compartment. Bottoms were 12 guage, side-'tops were 16 guage, and all inside work was ventilated by blower (presently, an air supplied respirator would be required). Stainless was used only for food grade transport, and all welds had to be ground, so this tank has probably already been repurposed. Alteration of bulkheads may increase possibility of flexing and cracking of total tank structure, so an engineering opinion should be obtained.

Al is correct: this is not a DIY project.

Manifold the external drains and use the drains and a pump, if necessary, to fill, rather than gravity. This would be my suggestion, if the project is undertaken at all.

By 803056

Date 07-06-2020 15:40

That's what we needed, someone with firsthand knowledge!

Thanks Northweldor.

Al