Semper Vaporo I see a marking for negative 1 bar.
I see a marking for negative 1 bar.
Is that one of those places where they serve Vodka on a ice table while you wear a parka?
I suppose that is more or less ok, as it is a "negative pressure" if you will. Pressure and vacuum are the units. Would still drive me crazy.
To refer to vacuum in negative inches, well, might as well hang the cross upside down.
Semper Vaporo
Pkgs.
All temperatures are above Absolute Zero - although we refer to water freezing as Zero on the Centigrade scale and Farenheit Zero is 32 degrees below water freezing and both scales have negative numbers. Numbers mean whatever people want them to mean - both positive and negative.
Never too old to have a happy childhood!
Back when I was engaged in the manufacture of semiconductor devices, there were two processes that made use of low pressure--around 10 millitorr--in quartz tubes. One Torr is 1/760 of one atmosphere; so this was a rarified atmosphere-and it was still expressed as a positive number. Some of the processes have, as I recall, the pressure measured in microns of mercury.
Johnny
Yes
RME NodakRanger Vacuum is not usually given in negative numbers. Vacuum can only be from 0 to whatever the local atmospheric pressure is. No negatives needed. Depends on whether you are using psia or psig. Many combination pressure/vacuum gauges have the in/mm of Hg (or of water) or the kilopascals or whatever below atmospheric marked in red and reading 'counterclockwise' from zero gauge.
NodakRanger Vacuum is not usually given in negative numbers. Vacuum can only be from 0 to whatever the local atmospheric pressure is. No negatives needed.
Depends on whether you are using psia or psig. Many combination pressure/vacuum gauges have the in/mm of Hg (or of water) or the kilopascals or whatever below atmospheric marked in red and reading 'counterclockwise' from zero gauge.
But they are still not negative numbers. I have seen lots of pressure/vacuum gauges. Every single one was in some way way marked "Pressure-PSI" and "Vacuum-In/Hg". (No reason they couldn't also be marked in kPa, or whatever unit you wanted to use).
Vacuum is not negative, it is simply a lower pressure when compared to another pressure.
rdamon Where was this filmed at?
Where was this filmed at?
@ http://www.progressiverailroading.com/mechanical/article/AllTranstek-tackles-imploding-tank-car-legend-on-MythBusters-TV-show--47621
From Progressive Railroading by Dainel Niepow Assoc Ed. ( March 2013)
FTA "...One of the biggest hurdles the producers faced? Obtaining cars they could test. So, the MythBusters team got in touch with rail consulting firm AllTranstek LLC, which provided general guidance, two DOT-111 tank cars, and a site in Boardman, Ore., to carry out the experiment..."
They didn't need a vacuum pump at all... just fill it conpletely with a semi-viscous liquid and drain it via a long hose but don't open the top pressure release valves. Water would work but you need to have a longer hose to keep it from gulping air back through the hose to release the (negative) pressure.
NodakRangerVacuum is not usually given in negative numbers. Vacuum can only be from 0 to whatever the local atmospheric pressure is. No negatives needed.
Vacuum is not usually given in negative numbers. Vacuum can only be from 0 to whatever the local atmospheric pressure is. No negatives needed.
any tank will implode if you pump the air out. Try an aluminum pop can. Put water in the can and set the can on a stove burner. Wait until steam is coming out of the can and then, using an oven mit, flip the can over in a pan of cold water. The steam condenses and the pressure in the can drops to zero -- the can implodes.
ndbprrDid they try to duct tape it together when they were done? Can't believe they had an episode without the tape being used.
I seem to recall duct tape being employed, either to secure the vacuum hose to the drain connection or to stop a leak - possibly both.
Chuck
They used a truck-mounted vacuum rig that went down to negative 25 inches of mercury - and only got results after they dented the cylindrical tank.
The tank they used was a modern all-welded design. If they had done the same thing with a transition era riveted tank it would have gone like a stepped on TP tube at about negative 15 inches. There have been plenty of examples in videos I have seen.
samfp1943 And it took them THREE tries to get the 'implosion' to work!
Based on a comment in the video, I'm guessing they didn't start with a big enough vacuum pump...
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
CandOforprogress2 https://www.youtube.com/watch?v=yBq5uapC-e0
https://www.youtube.com/watch?v=yBq5uapC-e0
Old News...
And it took them THREE tries to get the 'implosion' to work!
Perhaps you meant most recent, the Mythbusters final episodes aired a few weeks ago - ended with a bang.
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