Nitrox and titanium?

[JeffG]

heres agreat link that goes into "O2 cleaning"

http://www.dive-rite.com/TecTalk/o2_clean/index.htm

That is a great link.

 

[padiscubapro]

<sigh> I was making fun of the "O2" clean issue, but I guess I was unable to convey that to you. Well thats my fault for not communicating it properly.

and I couldn't give a rats %$#%$# what ANDI says. I do PP fills with un O2 clean tanks and I haven't killed myself..............yet

contamination is cumulative.. for the past several years most tanks were comming from the factory o2 clean (luxfer changed its policy no its by request only).

The tank is a BIG heatsink and unless its really bad the tank causing an explosion is pretty unlikely (you might get incomplete combustion, which you will not see, and an cause co and co2 in the mix - I HAVE seen results of tanks that had High CO2 and CO but the main system was clean.. besides someone skip breating this also MAY be a source for some of the CO2 headaches people occasionally report when using nitrox).. The valve is the most likely source of an ignition during filling.

The tank can cause problems when its delievering gas.. contamination from the tank can contaminate the valve (again this builds over time) so unless the air is really bad this contamination from the tank is minor (most contamination will come from the source onto the valve when filling). When using oxygen enriched mixtures I am much more concrned with partical imingements, any flaking from the tanks can cause an ignition when it comes into contact with another metal source..

In the andi gas blender class we show a short video where a few mg of particles were introduced to a supply line and pressurized with oxygen on an "OXYGEN CLEAN" system otherwise, and the system easily ignighted..

ANDI enforces strict gas standards on our facilities to guarantee good gas, over the last several years there have been deaths and accidents due to bad gas.

 

[miketsp]

Coming back to the original question on the thread, you may like to see the ignition curve for Titanium...
http://www.scubaboard.com/showpost.php?p=604078&postcount=6

Or then again maybe not.

 

[jrs_diesel]

Brass is a highly compatible metal which most regs are made of thats why people tendd to get away with things as long as the gas they breath doesnt have too much condensing hydrocarbons, Titanium is a completely another issue, It burns quite readily... Titanium regs have burned below 100% and have injured people.. There is no magic safety number, its about reducing risks.. Some metals self extinguish once, other metals burn util the material is gone (titanium is one of these)...





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A metal that can burn on its own is classified as a class D (or Delta) fire. These fires are unique as the material produces its own O². Magnesium and titanium are soe of the well known materials that can burn easily. When one of these fires start, very little can be done to extinguish them (since they produce enough oxygen to sustian combustion).