Steel or Alum? Used or New? Type of modifications: cutting one or both ends to shorten width wise, shorten height, putting a step in it to go around wheel wells, etc?
Basically, rinse with good grease cutting chemicals a couple of times. Depending upon the amount of modifications I still fill with CO2 after the rinse while welding. I use a flammables sniffer before striking any arc for cutting or welding. Once you have a certain opening size the CO2 isn't going to matter anymore because O2 will be getting into the fuel area.
Remember, it takes FUEL AND OXYGEN AND HEAT to have fire and/or explosion. REMOVE any one from the equation and you are safe. Do your best to eliminate one and greatly reduce both of the others and you have a good safety factor.
Thus, get the fuel out of there. Keep as much oxy away as possible. And, keep your heat down. While diesel is still explosive/flammable it is not as easily set off as gasoline.
Be safe, and Have a Great Day, Brent
Steel tank, used, need to 45 back corners to miss fenders.
Thanks for the info
Post a picture of the tank and what you're going to do to it.
Plus it is going to take a heck of a lot more to get diesel to explode.
Another oxygen removal tool.....several blocks of dry ice put inside the tank. Once the "smoke" starts pouring out the top, the oxygen has been pushed out. Sniffers are always a good idea.
Diesel & fuel oil boil above 300f [not all that hot]. Fuel vapor + oxygen goes bang if the mixture is anywhere near right or just flares up and singes all the hair off Your body if the mixture is way off.
When I was a kid I was brazing an oil pan still attached to the engine under the car. I started the job with all kinds of precautions, but had to continue with no precautions [too long a story for here]. It went off about like a shotgun blast. I was out from under that car in a split second. Then I thought about it a few seconds, and went back and finished the job, as for the next short while, the oxygen inside the engine had all been consumed.
Years later a "professional" scrap man was cutting up a large heating oil tank at the oil & coal yard in My nighborhood. He blew Himself to smitherenes when the several hundred thousand gallon tank detonated. His brother another "professional" scrap man told the newspaper "that tank had to have contained gasoline, because fuel oil won't blow" 2 idiots in the same family.
Take sufficient precautions, then You will be able to tell Us how the job went.
If it's a used tank, it's full of highly flammable gases very difficult to get rid of.
The American Petroleum Institute (www.api.org) has issued a recommended practice to weld on tanks that have contained oil products. I don't remember the practice number. Enter the API website and make a search.
Don't let Al use your brand new funeral shoes, tell him that he may use Dracula's, Frankenstein's or the Wolf Man's ones if he wants to.
Giovanni S. Crisi
Sao Paulo - Brazil
By the way, does the new generation know who were Dracula, Frankenstein and the Wolf Man? My generation got terrorized at watching their movies
According to the song, 2 of them were among the guests at the Monster Mash...
I did one yesterday. I am strictly a fill with water kinda guy. May not be practical on anything other than small holes etc. Reduces heat, removes oxygen, and no place for fuel to go. Really changes the fire triangle!
People spoke about sniffing the tanks. I would be curious to know if diesel fuel will generate vapors at room temp that are detectable with an explosimeter. Once the welding starts, then come the vapors. But this is just a speculation that I have never tried to research.
Gerald Austin
www.weldingdata.com
www.course.weldingclassroom.org (under development)
I agree with you there. I had to cut up about 20 gas tanks from cars that I hauled off. They would not take them even after years of sitting in the weather and I had no way to crush them. One garden hose stuffed in the spout and a cutoff wheel and grinder. When water poured out of the nozzle I went to cutting. No way possible way for it to explode that way. The water trick would work for welding just depends on what is being done I suppose.
I prefer my method most, "Can you fix my gas/diesel tank?". Nope. Odd, I'll weld on a live gas main though??? Guess it's because they are paying a ton of money where the bloke wanting me to weld on his gas tank or diesel tank is gonna want to sneak out of here by slipping me a 20.
Used to work in a tank shop many years ago, and every tank was steamed for at least 24hrs, with steam kept on while welding or cutting. Large tanks that could be entered were also pressure washed to remove scale before cutting or welding. Not even a flare-up in 30+years of operation.
Steam cleaning is the specified method for aircraft fuel tanks, or it was 30 years ago when My friends were in school.
I don't remember the required ammount of time, but it was specified.
Nitrogen purge is all you need. Nitrogen will purge the oxygen. I do it all the time.
Added a bunghole (dirty thoughts aside) to a diesel tank once...I guess they were using the right fuel! Before you mod a tank, make sure and confirm that it did, indeed hold diesel and only diesel! Used to use diesel for oil testing welds in one shop I worked at in the past (effective, imo! Why they didn't want to use die pen, I have no idea...), only to have to burn it off to weld the other side. Even with a cutting torch burning it off, that crap won't ignite easily!
been awhile since i checked in but thanks for the replys. i decdied to pass on this one not worth the possible problem.
thanks rj
Good call glad you've decided to stay with us because it may have been a real gamble if you did it
i watched a saftey man for a pipeline company put a lit cutting torch into a 5 gal bucket of dieserl trybas he might he could not get it to ignmite
he sdaid the diesel fuel needed bto be ccompresserd to burn .
The vapor is what burns/explodes. In an engine, the heat of compression ignites it.
Joe, that "safety" man is exactly the type I was mentioning above, and I hope he isn't still working!
You can do the same trick with a pail of gasoline, if you are Darwinian enough. The trick is make sure that the diesel is freshly poured into the pail, and not allowed to sit long enough to accumulate the required percentage of vapor to reach flash-point. Allow it to sit for a while in a still atmosphere (under a lid) and you will get a totally different result.
I personally witnessed the gasoline trick, (throwing a match in a pail of gasoline, and I didn't know it was going to happen!).
Since, diesel is less volatile, and has a higher flash-point temperature but is still heavier than air, challenging these tricksters to repeat their trick, with a container that has been allowed to sit for long enough for the required percentage of vapor to accumulate on the surface, will show whether ignorance or deliberate deception is at work.
I learned all about gas a diesel when I was a kid.. We lived in rural Arizona up in the mountains where it snowed a lot in the winter..
We had a big pit in our back yard where my parents were planning on building a cellar but never got around to it.. This pit became my experiment hide away with all sorts of things that should kill a child.. Small pipe bombs, fire crackers and different experiments with gas and diesel..
Mind you I was between 10 and 13yrs old at this point and I believe I wore out at least three of the best guarding angels available at the time..
Anyway I was going to make a hell of a bomb so I got one of Moms Ball canning jars and filled it up with gas swiped from the lawn mower.. I had a bunch of fuse string which to this day I don't know where it came from.. Anyway I set about a foot long fuse and ran like a scalded dog over to my dirt bank hiding spot.. To my shock the gas just lit and sat there doing a slow burn..
I later perfected it with some long empty 300 Winchester shells and a strip of T-shirt.. I would fill the shell with gas and put a tiny strip of T-shirt into the shell like a wick... It would burn like an oil lamp..
I have a 9yr old boy now and I'm sure he will put me through as much heck as I put my parents through.. I just got an Email from the man upstairs saying sorry but there are no guarding angels tough enough to handle him so I'm on my own..LOL
You know looking back when I was a kid I was SURE that everything I did was thought out and there was NO way I could get hurt.. It was simply impossible for me to get hurt..
Why Did Mom second guess my knot when I would slide down the rope tied to the top of a 50ft pine tree.. Now my son climbs up 20ft in a tree and I come uncorked... He is way more athletic than I was at his age and probably more daring... I think I'm screwed...!!!!
