[MBZ] air tanks

[R A Bennell]

I understand that water will generally just leak out through a pin hole in a tank. Water is not really compressed.
Air on the other hand, can split the tank wide open. There have been a number of reported cases of air tank
explosions. I tried to find out how to have my old Devilbiss tank tested. The proper way, (I was told at any rate)
was to fill it with water and pressurize it way beyond what one would normally run at. If it didn't spring any
leaks, it was then stamped as approved. I wasn't able to find anyone willing to do it for me and I expected that
the price might be silly anyway so I just bought a new tank and transplanted my compressor pump and motor to the
new tank. The cost was fairly reasonable as my nephew works at a store that sells things like that and he was able
to get me a good deal.

I also remember years ago (maybe close to 40 years) that a government inspector type person used to go around
looking for "boilers" which for some reason included air tanks. I watched him test one in a shop where I worked
back in highschool days, with a hammer. He just tapped it and listened to the sound. I guess if it had a
distinctive ring instead of a dull dead sound, it was considered to be safe.

Randy B

-----Original Message-----
From: Mercedes-bounces at okiebenz.com
[mailto:Mercedes-bounces at okiebenz.com]On Behalf Of David Brodbeck
Sent: Tuesday, June 20, 2006 3:02 PM
To: Mercedes Discussion List
Subject: Re: [MBZ] air tanks


R A Bennell wrote:
> I know a fellow who uses an old hot
> water tank for supplemental air but I am not sure I would do that. They are supposedly tested to something like
> 300# and he only runs about 100# of air but it still makes me a bit nervous.

It'd make me nervous, too.  Think about it...how do hot water tanks
usually fail?  Internal corrosion.  There's no way to know how much wall
thickness is left in the tank and how much of the original pressure
capacity is still left.  The amount of stored energy in 30 gallons of
air at 100 psi is not something you want to witness first hand.


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