That's the procedure they use for testing Scuba cylinders. It's called a Hydrostatic test. Immerse the cylinder in water and measure the additional displacement when the tank is pressurized as a test of the expansion properties of the metal. Old metal becomes brittle and does not expand as easily. They over pressurize the tank in the process to see if it bursts. They pressurize with water because it contracts less under pressure so that when a tank bursts, the damage to the test rig from the sudden release of pressure is minimal.
-Dave Walton On Jan 31, 2008 10:59 AM, R A Bennell <[EMAIL PROTECTED]> wrote: > My old compressor had a date stamp on the tank of 1947. It always made me > nervous too. I tried to find out how to > test it or what it would cost to have it tested without much success. I > remember way back when, the govt sent > around a fellow who tested just by banging with a hammer and listening to the > sound. I am told that the proper way > is with water. One needs to be able to pressurize the tank to something way > beyond normal with water. If it has any > faults, it will spring a leak but not explode apparently. > > My ultimate solution was to buy a new tank and transplant the compressor head > and motor etc to the new tank. No > problems since and I am careful to bleed off accumulated water regularly. > > Randy > > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Behalf Of OK Don > Sent: Wednesday, January 30, 2008 10:23 PM > To: Mercedes Discussion List > Subject: [MBZ] OT - tools to work on a Mercedes or four > > > I see that Harbor Freight has a 3/8" air ratchet on sale for $9.99. Is > there a chance that it would be useful? > > Also --- I inherited an old (1958) air compressor from my Dad. It ran > in his dental office for most of the years, and was taken care of > then, but has been sitting in the barn for the last six or seven > years. It runs OK, but does blow a fair amount of rust at the low > pressures I've let it build up. How do I determine whether the tank is > safe to get to 150 psi other than turning it one and leaving the house > for the rest of the day and praying? > > -- > OK Don, KD5NRO > Norman, OK > "There are three kinds of lies: lies, damn lies, and statistics." > -Benjamin Disraeli and/or Mark Twain > '90 300D, '87 300SDL, '81 240D, '78 450SLC, '97 Ply Grand Voyager > > _______________________________________ > http://www.okiebenz.com > For new parts see official list sponsor: http://www.buymbparts.com/ > For used parts email [EMAIL PROTECTED] > > To Unsubscribe or change delivery options go to: > http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > > _______________________________________ > http://www.okiebenz.com > For new parts see official list sponsor: http://www.buymbparts.com/ > For used parts email [EMAIL PROTECTED] > > To Unsubscribe or change delivery options go to: > http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com