Up in flames....no pun intended.

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cwkelley75

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When I was "working" in the trade, I worked for a company that made neurological mumbo jumbo. One of the parts I made were titanium bone screws. When I parted the screws off, I was left with a nasty "tit" for a lack of better words. To get this off, I would hit it on a grinder to preserve the life of my cutting inserts. Well, two weeks prior, the girlfriend spilled a large amount of laundry detergent on my jeans.

One day while grinding my bone screws, I feel a heat on my left leg. My first thought, Shop Shananigans a foot. I looked back expecting to see a co worker with a heat gun...nothing there. I ground two more screws and the heat became overwealming. I took another look and found my pant leg on fire and already gone almost to my knee!!!! Luckily, I was able to get the fire out and those jeans became shorts for the rest of the day.

I had washed the pants after the detergent was spilled, I assume it acted as an accelerant.
 
having ones pants on fire is no fun DNAMHIKT . I expect the detergent did one of two things . Possibly both. I expect most denim indeed most fabrics have some degree of treatment with flame retardant. the detergent may have removed the treatment. the other thing is various cleaning agents like clorine bleach oxy clean etc are oxidizers due help in combustion. be safe
tin
 
I suspect that the titanium dust caught fire all by itself. I was working in a plce once where a guy was grinding a magnesium fixture with an 8" snag grinder. As he was grinding, every now and then there would be a flash as the fine dust would ignite in mid air. Funny how you can weld and cut it when the heat can transfer but small enough particles will catch fire quickly.
My night man had a fire when he was fly cutting a face at high RPM and low feed. :fan:
 
The ends I was grinding would burn and seem to almost "evaperate" not long after being on the grinding wheel. Hopefully everyone can learn from my mishap.
 
Titanium can be a very dangerous material under the certain circumstances.

In solid state it has an auto-ignition temperature of 2200F.
That's pretty low.
Titanium powder in air, will auto-ignite at only 480F.

If you add a carbon base material to that formula such as oil, grease or detergent,
you will get a fire that can be as hard to extinguish as a magnesium metal fire is.

Glad to hear you were not seriously burnt!

Rick
 
Titanium can be a very dangerous material under the certain circumstances.

In solid state it has an auto-ignition temperature of 2200F.
That's pretty low.
Titanium powder in air, will auto-ignite at only 480F.
Rick
Hmm, that's interesting. The melting point of Titanium is 1660C, or 3020F.
 
All finely divided metals are potentially flammable, pyrophoric even.

The more finely divided, the greater the risk.

When you see sparks - that's not just "hot" its actually burning - the rate of heat being produced by oxidation is self sustaining - as particles become smaller, the surface area (and its ability to generate heat) gets exponentially greater than its volume (hence mass and ability to absorb heat) - so very small particles burn readilly and can even self ignite.

Ken

Pyrophoric.gif
 
Does anybody actually do that ?

Most people do not read a MSDS.

Any time you are working with an "exotic metal", you SHOULD!

I have never seen a titanium fire in person, but I have seen 2 cases
of magnesium fires in my machining career.
Both instances involved fine stringer chips lighting up.

The people working the magnesium were educated via the MSDS of how
to deal with that situation.

Someone who didn't know may have thrown water on the fire.
That would produce hydrogen gas turning a pile of smoldering chips into a
blow torch.

Hit it with a CO2 fire extinguisher, and the reaction will create magnesium oxide.
Now you have rocket fuel!

Is IS important to read the MSDS sheets!

Rick
 
+Adding fuel to the fire! I used to take my lunch hour down at this local airport near where I worked. This particular hanger/ shop was the home of Stolp Aviation, they built hand crafted aerobatic biplanes, namely the Stolp AcroDuster, StarDuster and few more. These aircraft were the absolute in craftsmanship and detail. I had been keeping progress watch on TR111 an Acro Duster, from start to this particular day. The fuse was covered with the engine on the fire wall, tail feathers installed and covered, all done up in silver ready for the color coats of a cream white. I was sitting in my car munching away on a sandwich and one of the guys walked up to the pedestal grinder about twenty feet from where this fusealage was sitting on its landing gear and started to take a fine cut on the wheel to a bracket he was fitting up. Well, let me tell ya , 4130 steel makes very fine high intense sparks when being ground, sure enough, a spark mades its way onto the aircraft somewhere, and it went up! Not only did it go up in flames, it consumed the fabric covering and the glue holding it to the structure, and litterly "cleaned" the tube chassis right down to the yellow painted metal of any and all little bits of chared material!, The fire ball was very note worthy as it roared out the hanger door! My mouth was full of sandwich and my eyes musta have bugged outta my head and I did manage to get outta the car, speechless! Seems the MEK and acetone, plus the clear dope had filled the interior of the craft with fumes as they were flashing off from the work several days before! Nothing eles caught on fire and there was some smoke in the hanger! Poor dude on the grinder mustta had to go change his shorts after that display!
 
Ya don't wear frayed jeans when welding either. I did when working on a hay rake and both legs got lit up. Looked like the dancer in the PI doing the candle dance. No real damage to me as I caught on pretty quick. My dad thought it was funny.
 
I used to machine Titanium parts for prosthetic joints and when taking a fine finishing cut i would get a "birds nest" of fine swarf which i could light with a cigarette lighter. The addition of a blast from an airline and it goes up like magnesium ribbon!
 
To be safe, read a current MSDS Sheet for what you are working with.

Rick
I'm in the automotive business and the most disturbing MSDS was for airbags. It seems the solid rocket fuel inside, that is made by Morton-Thiekol ,<-SP? , (yes the same people that got blamed for blowing up the space shuttle) has been "known to cause mutations in animals". Somehow I never got a warm and fuzzy feeling after reading that, and not wanting to grow a third leg, I have paid real close attention to all MSDS sheets and handling precautions contained therin.
 
Fine metal dust can be flamable even explosive. Powdered aluminium and iron oxide (basically rust) sounds harmless enough, but it is the recipe for thermite. A thermite reaction is extremely hot and vigorous. They use it for welding railway track (under carefully controlled conditions of course).

Finely divided dust clouds of even normally pretty harmless materials can be dangerous, I was once putting some new plant in a flour mill when there was a flour dust explosion. No one was seriously hurt, luckily, but the blast took every window out of the building, and blew me clean off my feet.

Flour milling equipment has spring loaded "Explosion doors" for just this reason and these prevented an unpleasant "Bang" from becoming a lethal one.

Regards Mark
 
As a point of interest, Nitric acid and Titanium do not play together well.
Nitric and Titanium will explode.
We had a customer change their deposition chemistry to include titanium without letting us know, our tech lowered the stainless parts with what was supposed to be only copper deposition into heated nitric.
Large boom, 70 gal of 170 degree nitric airborne.
Always wear your PPE!
Tech was unhurt, but the tank was trashed and the customer paid for an expensive hazmat cleanup.
Please don't try removing a tap from titanium with nitric!
Sam.
 
Does the powdered alum. and rust pertain to swarf.? Like fine metal dust laying around could be combustible? Or does this apply to airborne particles?
Had no idea about grain explosions and was raised in a farm community. As a boy I worked my share of dusty days on the farm, and with cows the added methane mix. lol Gotta respect the farmers a little more now
 
Does the powdered alum. and rust pertain to swarf.? Like fine metal dust laying around could be combustible? Or does this apply to airborne particles?
Had no idea about grain explosions and was raised in a farm community. As a boy I worked my share of dusty days on the farm, and with cows the added methane mix. lol Gotta respect the farmers a little more now
The mix has to be in a fairly tight range to make thermite, plus it needs to be fairly fine as well. It is difficult to ignite (normally a fuse of something like magnesium strip is used) but burns spectacularly when ignited. There is a common display at my uni where we light a small amount in a high temp vessel with a hole in the bottom, which is suspended over a tank of water with sand in the bottom. Liquid iron pours out the bottom hole into the water at such a high temperature that water is split into hydrogen and oxygen and burns as well. So we set water on fire! It is fun to see/do.

Grain dust explosions, while not common, were something we feared and had to deal with when harvesting wheat with the old equipment. Add in some wind and you could get a nasty dust mix swirling around inside the header, then a spark or failing (very hot) bearing would set it off. Again, much like petrol/gasoline and air, the ratio has to be correct or it won't burn. For example, an amount of petrol/gasoline in air of less than about 1.2% by volume will not even burn. Similarly, More than about 8% by volume in air won't burn either - it simply will not ignite. But between those two limits you have a bomb. Same goes with dust/grain explosions but with different rates.

Don't try this at home but...a little custard powder or non-dairy creamer in the palm of your hand then gently blown over a lit burner on your gas stove will yield an impressive flare and give you an idea of a dust explosions' potential.
 
As has been said earlier, a mixture of of aluminium turnings and literally rust will ignite to form what became German( in my case) incendiary bombs during WW2. I was a youngster with a former sapper father who was one of the blacksmiths in the coal mines who were not called up for military service. The only way to kill the beasts is to cool then down with a very fine spray of water or when there was no water to dig out turfs to literally smother them. After being machine gunned by a Heinkel 111K, it dropped 8 high explosives and 'breadbaskets' of incendiaries. One bomb was on a time fuse- as I know to my cost!

Another source of fire is an exotherm-as the name suggests. It can happen with oily rags, paint , resins and even grass cuttings. One of my family, his father was John Dobson the architect for Newcastle upon Tyne Railway Station- and a relative of the real Alice in Wonderland was killed by stored bird excrement- or fertiliser and he could only be recognised by the keys in what was left of his trousers. Common or garden( ?) dried urine will explode.

Incidentally, I'm deaf from working on relegated British ammunition. On a happier note a former Halifax bomber pilot known as 'Blaster Bates' did a recorded after dinner speech called 'A Shower of Sh1t over Cheshire' when someone blew up a farmers septic tank. Simply enjoy. the many UTubes!!!!!!!


Norm
 
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