A very, very good point @Bigbre04 , much like pressurizing containers that are not rated for pressure can cause damage and or harmso MOST gear(homebrew or pro) is not Vacuum rated. Hoses CAN be vacuum rated, mine randomly are, but the majority are not. Tanks are VERY VERY weak to vacuum...think about how you can suck a plastic bottle and crush it with your lungs but there is no world where you could pop it with your lungs.
I would say Pressure transfers are far safer then vacuum. Either way you have to be making up the volume with CO2. but if you can do that why not just use gravity and pressure combo?
Exactly. I wouldnt want to put much pressure on a glass carboy, but i would probably allow 1 or 2psi and a gravity transfer. generally speaking if you are just using a rubber bung or something that does not mechanically screw on that would be your safety valve for over pressuring a carboy imo atleast.A very, very good point @Bigbre04 , much like pressurizing containers that are not rated for pressure can cause damage and or harm
kegs are very tough.A keg can handle pressure. Purge the keg and pull it over it's not a sealed carboy your just sucking the liquid over.
I didn't say anything about a stopper in the carboy just stick the wand in. Sure it's not completely oxygen less transfer but may be a way to move star San in and out of a keg without wasting CO2
Look up rail car implosion. You pump out your product with out opening the vent and that tanker has a bad day. Those are allot sturdier than beer tanksYou can actually pump beer from tank to tank, but the tanks both need to be sealed and need to have an open hose between them to balance the pressure between them while preventing O2 from coming in. Not as common as just pressure transferring but it would def be faster, but there is a def risk factor involved. a pump can pull plenty of vacuum to crush a big tank. i have seen 1000 bbl tanks that had been imploded from temp or pressure differences. thats a bad day.
Yup exact same concept except sometimes those are carrying far nastier things than a Sparkle unicorn milkshake IPA...but not very often...Look up rail car implosion. You pump out your product with out opening the vent and that tanker has a bad day. Those are allot sturdier than beer tanks
You can think about it this way - under pressure, the sides of a vessel are under tension. Try taking a thin strip of metal and pulling on the ends. Chances are you cannot snap it!Yup exact same concept except sometimes those are carrying far nastier things than a Sparkle unicorn milkshake IPA...but not very often...
Do that with pop can too. Little water, boil it. Then tip upside-down over a tub of water. Will crush it flatYou can think about it this way - under pressure, the sides of a vessel are under tension. Try taking a thin strip of metal and pulling on the ends. Chances are you cannot snap it!
Under a vacuum, the vessel sides are put into a bending mode. Take that same strip of metal and I'll bet it bends pretty easily!
We used to do a science experiment at school - take an old, empty, 1 gallon oil can and put a little water in it. Put it over a heat source until the water is boiling, then screw the cap on and remove the heat! It collapses pretty spectacularly!
Myth Busters!