Propane bottle volume

Propane bottle volume

Post by Curti » Sun, 06 May 2012 06:15:10


"el stroko guapo"  wrote

Quote:
> But the 47.6 is not volume, it's the weight of the liquid propane.

Negative.

That is the weight of water, which is how the volume of DOT tanks is done.

Propane tanks use a 42% multiplier, other gasses uyse different numbers.

Note, .42 x 47.6  is 19.992, or 20 lbs.

 
 
 

Propane bottle volume

Post by Curti » Sun, 06 May 2012 06:41:50

Quote:
> When new and in good shape, they're rated for 300 psi

Actually, 375 psi.....ASME tanks are 250 psi, ASME Californies are 312 psi

Quote:
> Normally they never see more than 175 psi even if you leave them out in
> the sun

Unless painted a dark color.....

Anyways, too much damn engineering, reminds me of the time I prepiped a
house for  one of them NASA rocket scientists, you don't need to pinwheel
with a RPG.  The guy with my name misspelled sounded good.

Curtis

 
 
 

Propane bottle volume

Post by Steve » Sun, 06 May 2012 12:57:21


Quote:
> When new and in good shape, they're rated for 300 psi... Normally they
> never see more than 175 psi even if you leave them out in the sun, IIRC...
> Even 150 psi would be over 330 ft... Of course, the difference is that
> they
> are rated for INTERNAL pressure, not EXTERNAL pressure... For what you're
> talking about though, it's unlikely to be an issue, but if you are ultra
> paranoid, put 50 psi in them and you can go to around 112 ft and not have
> an external pressure greater than the internal pressure...

I really see only a few scenarios in their use.

1.  Leave valve open for 24 hours.  Close valve.  Never open valve again,
and use sealed.

2.  Cut out the valve and about a 2" hole around the valve, and use this
portion in the down position.  Fill manually with an air whip or with
regulator.  Tip tank underwater when wanted to dump buoyancy.

3.  Add a fill valve, maybe just a Schraeder, along with the 2" torch
cutout, and use a whip with a tire filler hose.

4.  Make a copper tube through the top (actually now the bottom, with it in
the inverted position), and have a fill/dump valve on the same line, so one
could bump up the buoyancy, or let a little out, and fine tune the lift as
needed.  Any excess would simply dump out the bottom (top of tank where cut
out, but now inverted), and exhaust itself.

The only danger area is when neutral buoyancy is achieved, and lift is
started.  In that scenario, there would be approximately 75-100# suspended,
and a blowup, and subsequent events could cause a problem.

That will have to be addressed in the field tests.

Steve

 
 
 

Propane bottle volume

Post by el stroko guap » Wed, 09 May 2012 01:55:41


Quote:

>> But the steel weights are more buoyant than the lead weights, and to be
>> exact you have to compensate for the buoyancy of the weights used.

> So you're saying that my aluminum travel weights won't work?

I use the collapsible plastic ones. Saves both volume and weight.

esg

 
 
 

Propane bottle volume

Post by el stroko guap » Wed, 09 May 2012 02:00:49


Quote:
> "el stroko guapo"  wrote

>> But the 47.6 is not volume, it's the weight of the liquid propane.

> Negative.

> That is the weight of water, which is how the volume of DOT tanks is done.

> Propane tanks use a 42% multiplier, other gasses uyse different numbers.

> Note, .42 x 47.6  is 19.992, or 20 lbs.

Hot damn! Learn something new every day!

esg

 
 
 

Propane bottle volume

Post by el stroko guap » Wed, 09 May 2012 02:06:10


Quote:

>> When new and in good shape, they're rated for 300 psi... Normally they
>> never see more than 175 psi even if you leave them out in the sun, IIRC...
>> Even 150 psi would be over 330 ft... Of course, the difference is that
>> they
>> are rated for INTERNAL pressure, not EXTERNAL pressure... For what you're
>> talking about though, it's unlikely to be an issue, but if you are ultra
>> paranoid, put 50 psi in them and you can go to around 112 ft and not have
>> an external pressure greater than the internal pressure...

> I really see only a few scenarios in their use.

> 1.  Leave valve open for 24 hours.  Close valve.  Never open valve again,
> and use sealed.

> 2.  Cut out the valve and about a 2" hole around the valve, and use this
> portion in the down position.  Fill manually with an air whip or with
> regulator.  Tip tank underwater when wanted to dump buoyancy.

> 3.  Add a fill valve, maybe just a Schraeder, along with the 2" torch
> cutout, and use a whip with a tire filler hose.

> 4.  Make a copper tube through the top (actually now the bottom, with it in
> the inverted position), and have a fill/dump valve on the same line, so one
> could bump up the buoyancy, or let a little out, and fine tune the lift as
> needed.  Any excess would simply dump out the bottom (top of tank where cut
> out, but now inverted), and exhaust itself.

> The only danger area is when neutral buoyancy is achieved, and lift is
> started.  In that scenario, there would be approximately 75-100# suspended,
> and a blowup, and subsequent events could cause a problem.

> That will have to be addressed in the field tests.

> Steve

If there's a hole in the tank, the air inside will shrink to ambient,
water will enter, and the buoyancy will be reduced pretty dramatically.
Like by half at only 33 fsw.

esg

 
 
 

Propane bottle volume

Post by Steve » Wed, 09 May 2012 02:16:32



Quote:



>>> But the steel weights are more buoyant than the lead weights, and to be
>>> exact you have to compensate for the buoyancy of the weights used.

>> So you're saying that my aluminum travel weights won't work?

> I use the collapsible plastic ones. Saves both volume and weight.

> esg

I prefer the inflatables.

Steve

 
 
 

Propane bottle volume

Post by Steve » Wed, 09 May 2012 02:17:12



Quote:



>>> When new and in good shape, they're rated for 300 psi... Normally they
>>> never see more than 175 psi even if you leave them out in the sun,
>>> IIRC...
>>> Even 150 psi would be over 330 ft... Of course, the difference is that
>>> they
>>> are rated for INTERNAL pressure, not EXTERNAL pressure... For what
>>> you're
>>> talking about though, it's unlikely to be an issue, but if you are ultra
>>> paranoid, put 50 psi in them and you can go to around 112 ft and not
>>> have
>>> an external pressure greater than the internal pressure...

>> I really see only a few scenarios in their use.

>> 1.  Leave valve open for 24 hours.  Close valve.  Never open valve again,
>> and use sealed.

>> 2.  Cut out the valve and about a 2" hole around the valve, and use this
>> portion in the down position.  Fill manually with an air whip or with
>> regulator.  Tip tank underwater when wanted to dump buoyancy.

>> 3.  Add a fill valve, maybe just a Schraeder, along with the 2" torch
>> cutout, and use a whip with a tire filler hose.

>> 4.  Make a copper tube through the top (actually now the bottom, with it
>> in
>> the inverted position), and have a fill/dump valve on the same line, so
>> one
>> could bump up the buoyancy, or let a little out, and fine tune the lift
>> as
>> needed.  Any excess would simply dump out the bottom (top of tank where
>> cut
>> out, but now inverted), and exhaust itself.

>> The only danger area is when neutral buoyancy is achieved, and lift is
>> started.  In that scenario, there would be approximately 75-100#
>> suspended,
>> and a blowup, and subsequent events could cause a problem.

>> That will have to be addressed in the field tests.

>> Steve

> If there's a hole in the tank, the air inside will shrink to ambient,
> water will enter, and the buoyancy will be reduced pretty dramatically.
> Like by half at only 33 fsw.

> esg

Yes, and can thereby be adjusted.

Steve

 
 
 

Propane bottle volume

Post by Grumman-58 » Wed, 09 May 2012 09:24:25



Quote:
> Anyways, too much damn engineering, reminds me of the time I prepiped
> a house for  one of them NASA rocket scientists, you don't need to
> pinwheel with a RPG.  The guy with my name misspelled sounded good.

Awh, just run 2" pipe to every place he needs it, that should give enough
of a margin of error for any engineer... If he needs more than a 2" line to
his BBQ pit, I'm impressed...
 
 
 

Propane bottle volume

Post by Curti » Wed, 09 May 2012 09:43:18

"Grumman-581"  wrote

Quote:
> Awh, just run 2" pipe to every place he needs it, that should give enough
> of a margin of error for any engineer... If he needs more than a 2" line
> to
> his BBQ pit, I'm impressed...

Speaking as an old pro, cannot remember _ever_ piping a house using larger
than 1 1/4".

Before I'd use 2", I'd do a 2 lb system.

 
 
 

Propane bottle volume

Post by Curti » Wed, 09 May 2012 09:47:38

"el stroko guapo"  wrote

Quote:
> Hot damn! Learn something new every day!

Only fair, you've taught me much.......

Just won't comment on using cylinders for lift bags, even if I have used a
couple in the past for HP rifle targets.  ;-)

 
 
 

Propane bottle volume

Post by Grumman-58 » Wed, 09 May 2012 10:08:55



Quote:
> Speaking as an old pro, cannot remember _ever_ piping a house using
> larger than 1 1/4".

> Before I'd use 2", I'd do a 2 lb system.

Only 1 1/4"?  Hell, I used a 1" just for my BBQ pit...

Then again, you remember that little burner I was running down in Florida
on that trip a few years ago... :)

 
 
 

Propane bottle volume

Post by el stroko guap » Wed, 09 May 2012 11:47:57


Quote:




>>>> But the steel weights are more buoyant than the lead weights, and to be
>>>> exact you have to compensate for the buoyancy of the weights used.

>>> So you're saying that my aluminum travel weights won't work?

>> I use the collapsible plastic ones. Saves both volume and weight.

>> esg

> I prefer the inflatables.

> Steve

***** (five stars, first of 2012)
 
 
 

Propane bottle volume

Post by Curti » Fri, 11 May 2012 07:38:00

"Grumman-581" wrote

Quote:
> Only 1 1/4"?  Hell, I used a 1" just for my BBQ pit...

Only you and NASA sizes piping that way.  ;-)

Quote:
> Then again, you remember that little burner I was running down in Florida
> on that trip a few years ago... :)

Biggest thing I remember is that the lawyer dude, old whats-his-name, didn't
show so we could cook his goose......
 
 
 

Propane bottle volume

Post by Grumman-58 » Fri, 11 May 2012 09:41:36



Quote:
> Biggest thing I remember is that the lawyer dude, old whats-his-name,
> didn't show so we could cook his goose......

You don't remember the 6+ ft of flame that I had coming out of that burner
when I just turned it up about halfway?