i use my bottle of C02 to rack from carboy to carboy, works great
thanks
gary
--
Dan Listermann
Check out our E-tail site at http://www.listermann.com
Take a look at the anti-telemarketer forum. It is my new hobby!
"gary" <g...@execpc.com> wrote in message
news:c6e3f3a6.02011...@posting.google.com...
I'd never go over a couple of psi.
I recently dry hopped a beer and wanted to sink/wet some of the leaf hops.
I covered the top of the carboy with saran wrap, and shook, it a matter of
seconds the saran expanded and popped due to CO2 coming out of solution.
If nothing is clogged in the system, then the pressure won't build up, but
if you got a clog somewhere and the pressure was too high, then BOOM.
I'd hate to see your name pop up on a stupid brewers trick list, so keep the
pressure low.
Cheers,
Mike
ek
Mark
MDixon <mdixon_...@ipass.net> wrote in message
news:u3ttkd...@corp.supernews.com...
We have some folks on the list who've brewed with fruit. Some of them have
done so in a carboy -- once. When the fruit clogged the carboys, resulting
in an explosive release of wort through the mouth of the carboy, how high
did the gushers reach? We know (roughly) the weight of the wort, we know
the force of gravity, and we know that the carboys withstood the pressure
necessary to raise a column of wort (if only briefly). We know the diameter
of the mouth, which should enable us to derive the pressure in the carboy
from the known force necessary to raise the wort. With the final data point
of the height of that column, we should be able to calculate at least a
"known attained" pressure, no? :-)
Alternatively, has anyone every *exploded* a carboy with a fruit clog?
Just some playful thoughts...
- Lars D. H. Hedbor
Probably not too much, and I wouldn't be in a big hurry to find out what it
is.
You probably only need a few psi to transfer (especially if the empty is at
a lower elevation than the full one), so you don't really need to worry.
"gary" <g...@execpc.com> wrote in message
news:c6e3f3a6.02011...@posting.google.com...
--
Dan Listermann
Check out our E-tail site at http://www.listermann.com
Take a look at the anti-telemarketer forum. It is my new hobby!
"Lars Hedbor" <lhe...@nosmap.hotmail.com> wrote in message
news:ThG%7.5442$Vq.42903@rwcrnsc53...
Okay -- so now we can start putting some boundaries on the problem, no? Was
there anything restricting the "nozzle" of your wort jet, or was it just the
mouth of the carboy? (i.e., did it blow right *through* the airlock, or did
the yeast discard the airlock along with the bag, as being unnecessary to
their mission at that point?)
This is going to be a fun exercise! :-) (More fun than cleaning up was,
eh?)
>does anyone know how many psi a carboy can withstand.
About 1 pound less than you'll subject it to the next time the lines
get plugged. :)
Use a stopper and make sure it's not rammed in really tight, so the
worst that can happen is that the stopper blows out. It may ruin a
great batch, but *you'll* still be in good enough shape to brew more.
[Apparent Rennerian 567.7, 95.9]
--
Al - rukbat at optonline dot net
--
Dan Listermann
Check out our E-tail site at http://www.listermann.com
Take a look at the anti-telemarketer forum. It is my new hobby!
"Lars Hedbor" <lhe...@nosmap.hotmail.com> wrote in message
news:jzK%7.7026$uA.6...@rwcrnsc51.ops.asp.att.net...
>You can probably use the C02 to start your siphon. I wouldn't use it to
>"pressure transfer" the wort, you are just asking for trouble.
You just put the "receiver" lower than the "supplier", connect the gas
tube between the two of them and, after the siphon starts it's still
an airless transfer, if the two carboys (or carboy and Corny) were
purged at the beginning.
---
[Apparent Rennerian 567.7, 95.9]
>does anyone know how many psi a carboy can withstand.
>
>i use my bottle of C02 to rack from carboy to carboy, works great
A few months ago I calculated how much total pressure there was on the
inside of a 5 gallon glass carboy at 15 psi. If memory serves it was
MANY tons, over 10 tons. THe post is probably in the archives. The
point was, DO NOT pressurize a glass carboy with a CO2 tank. Blowing
into it is fine as no one can generate enough pressure with their
lungs to explode a glass carboy.
Domenick Venezia
Venezia & Company, LLC
Maker of PrimeTab
Seattle, WA
(206) 782-1152 phone
(206) 782-6766 fax
demonick at zgi dot com
http://www.primetab.com
thanks for all the replys. i use only 1 to 2 psi when transfering
the beer from one carboy to another. since i use a regulator i dont
think a clog would cause a runaway over pressure. i do where safety
glasses though.
i've been doing pressurized transfers because siphoning is just a pain
in the butt. most of the time i end up with vapor lock in the hose and
have to attempt to re-start the siphon or just toss the leftover beer.
another reason that i do the pressurized transfer is that i dont have
to disturb the beer by moving it to a higher elevation. i think that
im going to invest in a positive displacement pump that can lift the
beer from the carboy an transfer it into another.
thanks
>thanks for all the replys. i use only 1 to 2 psi when transfering
>the beer from one carboy to another.
That's per SQUARE INCH of surface on the inside of the carboy. How
many square inches are on the inside surface of a carboy? A few
hundred? That's a few hundred (or twice a few hundred) pounds of
pressure.
>since i use a regulator i dont
>think a clog would cause a runaway over pressure.
That depends on how much TOTAL (not psi) pressure the glass can
sustain.
> i do where safety glasses though.
They don't protect your legs, arms, head, etc.
--
"gary" <g...@execpc.com> schreef in bericht
news:c6e3f3a6.02011...@posting.google.com...
Uhh, no see the other post by jpstod.
>
> That depends on how much TOTAL (not psi) pressure the glass can
> sustain.
Uhh, wrong again. It is psi, and it is total psi. Now you can calculate the
pressure in some other unit, say pounds per total surface area, or pounds
per square foot, but it will equal the psi applied. If you want to play with
numbers, 1 psi = 144 psf.
So everyone should have 5' of 3/16" restrictor dispensing tubing at 1440
psf. Not quite as much fun is it?
Cheers,
Mike
The SAFE way??????? I don't think so...
One clog, or a weak spot in the Carboy = BOOM!
IMO the carboy would be good to about 5 and maybe up to 10 psi, but I am not
willing to find out at what point it becomes a grenade...
Cheers,
Mike
Why did you think that?
>"Al Klein" <ruk...@optonline.net> wrote in message
>news:3at14u8nve2ovn924...@4ax.com...
>> On 12 Jan 2002 10:34:33 -0800, g...@execpc.com (gary) posted in
>> rec.crafts.brewing:
>> >thanks for all the replys. i use only 1 to 2 psi when transfering
>> >the beer from one carboy to another.
>> That's per SQUARE INCH of surface on the inside of the carboy. How
>> many square inches are on the inside surface of a carboy? A few
>> hundred? That's a few hundred (or twice a few hundred) pounds of
>> pressure.
>> >since i use a regulator i dont
>> >think a clog would cause a runaway over pressure.
>> That depends on how much TOTAL (not psi) pressure the glass can
>> sustain.
>HUUUHHHHH
> I always thought x psi was x psi not that it
>multiplied by the number of square inches. So if you have 100 1 square
>inches with 2 psi in them and you put them all together you now have 200 psi
That's what I said. If the glass can sustain 180 pounds total
pressure, and you have 100 square inches, 2 psi will make a carboy
grenade.
Because they don't teach conversion in math any more. Although it's
close - you have 200 pounds per 100 square inches. Or 200/100 psi.
Burp,
-Dan
"ben w" <her...@dalymount.com> wrote in message
news:65612c80.0201...@posting.google.com...
Also since kegs are only rated for 300 psi and we use an average of 10 psi
people would be blowing kegs up...using your theory of compounding we would
only be able to apply no more than 1 psi since as a quick quess I am sure
that there is more cubic inches inside. Compound 10 psi inside 300 cubic
inches it would give you 3000 total about 2700 more than the max rated
pressure
lets see if I remember my formulas right
Pie x diameter x height = cubic inches for cylinders
so a keg would be roughly
3.14 x 12 x 24 = 904.32 cubic inches
so on an average we have a load of 9043.2 pounds of pressure on a keg using
compounding..and when people use 35 psi then that would be 31651.2 pounds
the actual psi never changes in 2 psi will never equal more than 2 psi.
The average person can apply more than 5 psi just gripping something so we
stand a better chance of breaking a carboy by just picking it up if 2 psi
will make a grenade
"Al Klein" <ruk...@optonline.net> wrote in message
news:d6064u8vjkvtethv7...@4ax.com...
--
Dan Listermann
Check out our E-tail site at http://www.listermann.com
Take a look at the anti-telemarketer forum. It is my new hobby!
"D Schultz" <schu...@msn.com> wrote in message
news:3c443749$2...@news.bubbanews.com...
Your equations are slightly askew, but your point is well made.
...For the record: (pi x diameter x diameter / 4) x height = cubic inches
Cheers,
Mike
Uhmmm... me thinks that the formula for the volume of a cylinder is:
p * r * r * h
i.e. the surface of the circle is moved through the plane of distance
'h', thus it's volume is the area of a circle times the distance.....
Matt
>does anyone know how many psi a carboy can withstand.
>
>i use my bottle of C02 to rack from carboy to carboy, works great
Here's some real numbers. A 12" diameter 12" high cylinder has a 678
square inch internal surface area. At 15 psi that's over 10,000
pounds (5 TONS) of total pressure. At 5 psi that's still almost 3400
pounds of total pressure.
A 5 gallon carboy is taller than 12".
A person with a CO2 tank, tubing, and a one-hole stopper can EASILY
withstand 15 psi when pressing the stopper into the mouth of a carboy.
Mouth of the carboy is maybe 4 square inches, for a total pressue
exerted upward of 60 lbs. Easily resisted by leaning on it just a
little.
I saw a cute mnemonic on a math web site the other day....they were
talking about the volume of a somewhat-idealized cylindrical pizza of
radius z and thickness (height) a:
Volume = pi暘暘戢
ObBrewing: Ummmmm, doesn't everyone love a nice homebrew with their
pizza? Yeah, that's it!
JeffMo
After reading thru the posts on max pressure for a carboy I thought I
would offer my two cents on the issue. Pressure vessels are designed
to withstand a maximum pressure within the vessel, not the total
distributed load on the walls. The primary considerations here are the
materials ultimate tensile strength (the value at which you expect the
material to fail under tension), the outside diameter, the inside
diameter and the shape of the ends. Hemispherical ends allow for
easier stress calculations than the shape of most carboy bottoms.
When pressure is applied inside your carboy the walls will be forced
outward. The walls act as a ring and develop tensile stress to resist
this outward pressure and is known as "hoop stress". Hoop stress is
the largest stress component your carboy must deal with.
Also, the ends of the carboy receive stress pushing them along the
long axis of the carboy. This stress is much less than the hoop stress
but is significant and must be considered in the calculations.
Finally, glass is unpredictable when stressed in tension. Scratches,
microscopic cracks, inclusions and other imperfections create high
localized stresses ultimately causing failure. For this reason glass
is not used as an engineering material in tension (exemption given to
glass fibers but that's a different critter).
Ok, on to some quick and dirty calculations:
Hoop stress = (Pressure head*OD of carboy+ID of carboy/2)/ 2* wall
thickness of carboy
When I use 10psi for the pressure head, an OD of 11" and a wall
thickness of ź" I get a hoop stress of 13.4 lb/in^2
Longitudinal Stress = (Pressure head*OD of carboy+ID of carboy/2)/ 4*
wall thickness of carboy
I got a longitudinal stress of 6.7 lb/in^2
The resultant force is a nice and easy (hoop stress^2 + longitudinal
stress^2)^1/2
This means my carboy at the outer surface of the shoulder sees a
stress of 13.4 psi when I pump in 10 psi from my co2 bottle. Yes, the
bottom corners receive more stress but I cant figure that out without
some computing firepower that I don't have access to at home. At the
end of the day you ask yourself is a stress 13.4psi a lot? I will say
no based on the fact that similar materials such as concrete are rated
for 900psi and with a safety factor of 5 that gives us an upper stress
limit, not allowable pressure, of 180psi.
Ok, I think I have exceeded my 2 cents worth on this one and I
apologize for the long-winded post.
Snip>> Some tech stuff
The moral of my tale is: I would suggest using a device such as a
carboy cap with a known allowable pressure (less than the carboy
bursting pressure) that will act as a pressure relief valve should
your line clog. That way you will be protected from blowing your
carboy.
Giz
g...@execpc.com (gary) wrote in message news:<c6e3f3a6.02011...@posting.google.com>...
> does anyone know how many psi a carboy can withstand.
>
> i use my bottle of C02 to rack from carboy to carboy, works great
>
> thanks
>
> gary
So, have you blown one up? Seems easy. *Somehow* get an airtight fit
on the neck with your CO2 tank set for 0 lbs. Use the adjustment
screw on the regulator to increase pressue a pound at a time, Let the
carboy sit 1 minute at each pressue point. Continue until failure.
Better take containment precautions.
I have a 5 gallon carboy that I might sacrifice if I have the time to
do it. Someone suggest how to get a gas-tight seal on the neck.
Cheers!
Domenick Venezia
Seattle, WA
>I have a 5 gallon carboy that I might sacrifice if I have the time to
>do it. Someone suggest how to get a gas-tight seal on the neck.
A carboy cap and duct tape.
I like Al's idea of duct tape, but with a stopper. I also think it would be
good to put the carboy in a plastic mesh grain bag after everything is
secured to keep flying shards under control. Also, I would let the pressure
increases equilibrate for a minute or two prior to increasing to the next
psi setting.
Cheers,
Mike
Jason
>Domenick Venezia <demo...@zgi.com> wrote in message
>news:3c52dce6...@news.qwest.net...
>> I have a 5 gallon carboy that I might sacrifice if I have the time to
>> do it. Someone suggest how to get a gas-tight seal on the neck.
>I like Al's idea of duct tape, but with a stopper. I also think it would be
>good to put the carboy in a plastic mesh grain bag after everything is
>secured to keep flying shards under control.
Or what we used to do to make TV picture tubes safe - put the carboy
in a carton. Put that carton inside another carton. If you really
want safety, make the outside carton about 12" larger (all around)
than the inside one and fill the spaces (about 6" on a side) with
corrugated cardboard.
--
== Mike Uchima == uch...@pobox.com == http://www.pobox.com/~uchima ==