Welding Diesel fuel tank

[bundyrum4x4]

I want to modify my long range tank in my Mav to allow more rome for the trailing arms.
What do I need to do to prevent a big bang while welding the tank?

[RaginRover]

dunno but at a guess

drain, rinse with water and morning fresh, scrub the gunge out of it while you are there, let it dry and then repeat ??

There are a couple of blokes on here who will know for sure but that is my guess

Tom

[ausyota]

run a pipe from a car exhaust and fill it with exaust fumes.
much better way than using water caus water and diesel aint a good mix in a motor .

[bazzle]

Take it to Brown Davis or Long Ranger

Bazzle

[Damo]

Another method is to fill the tank with an inert gas, Argon for example.

Use the flow meter (measures flow in litres per minute) to figure out when your tank is going to be full. Another thing to consider is if your inert gas is heavier or lighter than air, and position your filler appropriately.

I've never done this but my instructor at TAFE has used this method many times. Mind you, another one of my TAFE instructors says he never touches fuel tanks

Diesel is less volitile than unleaded, I wonder if that would make any difference. I suppose if it's ignition point is at a higher temperature it would...

[V8Patrol]

Another method is to fill the tank with an inert gas, Argon for example.

Use the flow meter (measures flow in litres per minute) to figure out when your tank is going to be full. Another thing to consider is if your inert gas is heavier or lighter than air, and position your filler appropriately.

I've never done this but my instructor at TAFE has used this method many times. Mind you, another one of my TAFE instructors says he never touches fuel tanks

Diesel is less volitile than unleaded, I wonder if that would make any difference. I suppose if it's ignition point is at a higher temperature it would...

CORRECT A MUNDO ! :D

[bundyrum4x4]

This is what I need to do in red. Not a difficult job, if it wasn't for the risk of a big bang. I was going to de-grease the tank ( to remove oil content on the diesel ) then allow to dry for a few days.
From the replys I take it that this would not be safe.

Perhaps it will be better to take it to LRA.

[bundyrum4x4]

Pic wont work , I will post it up once I work out the prob.

[bundyrum4x4]

Got it

[Hybrid]

I've got mate that owns a earth moving company out west. As a result they have a ton of 44 gallon drums of diesel left over. He reckons that they can empty em leave em open for months and still get a decent bang when they cut. I think he was saying somehting about fuel be still trapped in the seams or something.

[Damo]

I've got mate that owns a earth moving company out west. As a result they have a ton of 44 gallon drums of diesel left over. He reckons that they can empty em leave em open for months and still get a decent bang when they cut. I think he was saying somehting about fuel be still trapped in the seams or something.

Yep, apparantly once it's had fuel in it you can never really get it out 100%. So rather than remove the accelerant use an inert gas to displace the oxygen. No oygen = no bang.

I'd still be wearing my brown undies though

[Snatchy]

http://www.osh.dol.govt.nz/order/catalo ... otwork.pdf

[bundyrum4x4]

Thanks Snatchy, that booklet helps heaps.

[Carl Coight]

I've welded a few fuel tanks for people and all i usually do is run the hose in the tank for a while (fuel floats) and just flush it out. Done several tanks and never had a drama.

[berazafi]

bad news welding tanks, steel is slightly porus when you heat it it releases the fuel

[ozy1]

i welded a tank out of my MQ petrol, just drained it, and hosed through for a few miutets then welded away.

[bazzle]

i welded a tank out of my MQ petrol, just drained it, and hosed through for a few miutets then welded away

You were Very lucky.
Ive read accident files on where people have done this and CABOOM

Petrol fumes can be absorbed into the surface molecules of steel.

Bazzle

[RUFF]

We weld Alloy Truck fuel tanks all the time at work. We need to shorten a lot of them to get our AC units fitted. All we do is drain them Cut them wash them out with dishwashing liquid and then tig weld the ends back on. Have never had a problem.
I have also welded petrol tanks and uasually just find a hose that fits over the exhast of a car and leave the hose in the tank filler with the car running at normal running temp and weld away. Exhast gas is inert as long as the vehicle is healthy. Dont do it with a car that runs rich.

[4sum4]

When I did mine a gave it a spuirt with a fire extinguisher and sealed it of with glad rap and elastic bands then hosed it out