AMRAD at Hamvention

Mike O'Dell mo at
Sun May 13 10:48:24 CDT 2012

D'OH!, i have seen the tube trailers and seen the legends.
3200 PSI or so.  "The look of real steel!"

found this in passing.....


On 5/13/12 8:31 AM, Robert E. Seastrom wrote:
> Mike ODELL<mo at>  writes:
>> A big issue with H2 tankage is that embrittlement is a serious
>> problem which is magnified by the high pressure need to get much H2
>> a given volume.
> Why didn't I think of that?  Answer: I only think about hydrogen
> embrittlement when I've got an electrode holder in my hand and am
> reaching for the E7018 rather than the E6010 or 6011.  So I only
> associate it with high temperatures.  Funny how high pressure makes
> the same thing happen.
>> I suspect that makes cylinder re-use a rather riskier proposition,
>> enough so that it probably wrecks the usual cylinder gas economics.
>> Most places I know of that really use externally supplied H2 take it
>> as a cryo-slurry because of the volumetric efficiency of storage and
>> transport.
> But folks take delivery in tube trailers too.  You'd think they'd
> suffer from the same issues.  Hydrogen damages both steel and aluminum
> - what are the tube trailers made out of?
> I know the valves for He are "special" and not just with the outlet
> threading (that's connector conspiracy for a good reason, don't want
> to hook up dry nitrogen to the medical oxygen line lest you have a
> hospital full of dead people).  Is it the tanks themselves that you'd
> be more worried about?  Maybe they just don't last "forever" and need
> to be aged out - I've fairly routinely gotten pool tanks for less
> aggressive stuff that had ICC approval stamps instead of DOT and first
> hydro test stamps that were in the 1930s.
>> Btw - it was NASA that figured out how to slurry H2 because that's the
>> only way to carry enough to actually use it  fuel. Even pure LH2 has crappy
>> density compared to slurry. The most amazing part is that it's done easily with a catalyst
>> instead of insane pressure and the slurry is far more stable and flows better
>> In the fuel lines than pure LH2.
>> Just one more area of technology that barely existed at all before Project Apollo -
>> Producing, handling, and using cryogens in industrial quantities.
> Too cool for the 50s, had to wait for the 60s.  I'm hip.  :)
> -r

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