Now that I'm familiar with how to remove a propane tank valve, what if
I filled the tank about halfway with water, plumbed in regular black pipe
plumbing with a sturdy tee with blowoff valve set for like 200 psi and
a beefy gate valve, and set it on my outdoor propane burner (for deepfat
turkey frying) to generate steam for steam cleaning? The tank's supposed
to be good to 250 psi. Could this generate enough steam to do anything
useful? Steam whistle at a logging show? Anything?

GWE
on a propane tank binge

Grant Erwin wrote:
Now that I'm familiar with how to remove a propane tank valve, what if
I filled the tank about halfway with water, plumbed in regular black pipe
plumbing with a sturdy tee with blowoff valve set for like 200 psi and
a beefy gate valve, and set it on my outdoor propane burner (for deepfat
turkey frying) to generate steam for steam cleaning? The tank's supposed
to be good to 250 psi. Could this generate enough steam to do anything
useful? Steam whistle at a logging show? Anything?

GWE
on a propane tank binge

That would make good steamer for steam bending wood. I've use an empty
paint can for the boiler, but in my mind's eye I envisioned something
more like what you describe.

--
Gary Brady
Austin, TX
www.powdercoatoven.4t.com

On Fri, 21 Jan 2005 16:57:47 -0800, Grant Erwin
wrote:

Now that I'm familiar with how to remove a propane tank valve, what if
I filled the tank about halfway with water, plumbed in regular black pipe
plumbing with a sturdy tee with blowoff valve set for like 200 psi and
a beefy gate valve, and set it on my outdoor propane burner (for deepfat
turkey frying) to generate steam for steam cleaning? The tank's supposed
to be good to 250 psi. Could this generate enough steam to do anything
useful? Steam whistle at a logging show? Anything?

I figure 25,000 BTU/hr would make about 6 CFM of steam at 2 bar (29.4
PSI). That's neglecting losses; I just used heat of vaporization
and density of steam.

Don Foreman wrote:
On Fri, 21 Jan 2005 16:57:47 -0800, Grant Erwin
wrote:


Now that I'm familiar with how to remove a propane tank valve, what if
I filled the tank about halfway with water, plumbed in regular black pipe
plumbing with a sturdy tee with blowoff valve set for like 200 psi and
a beefy gate valve, and set it on my outdoor propane burner (for deepfat
turkey frying) to generate steam for steam cleaning? The tank's supposed
to be good to 250 psi. Could this generate enough steam to do anything
useful? Steam whistle at a logging show? Anything?


I figure 25,000 BTU/hr would make about 6 CFM of steam at 2 bar (29.4
PSI). That's neglecting losses; I just used heat of vaporization
and density of steam.


Are regular hardware store pipe fittings able to take the pressure?
What was that old saying about a chain and a link?

Ken Grunke

--
take da "ma" offa dot com fer eemayl

Grant Erwin wrote:

Now that I'm familiar with how to remove a propane tank valve, what if
I filled the tank about halfway with water, plumbed in regular black pipe
plumbing with a sturdy tee with blowoff valve set for like 200 psi and
a beefy gate valve, and set it on my outdoor propane burner (for deepfat
turkey frying) to generate steam for steam cleaning? The tank's supposed
to be good to 250 psi. Could this generate enough steam to do anything
useful? Steam whistle at a logging show? Anything?

GWE
on a propane tank binge

Use caution, pressure capabilities change with temperature. I guess I'd
want to know at what temperature is it rated 250 psi , and how hot is
200 pound steam?

Paul
--
-----------------------------------------
It's a Linux world....well, it oughta be.
-----------------------------------------

One of the model engineering magazines, HSM I think, had an letter from a
boiler inspector about this very subject. He went on about pressure vessels
and heated pressure vessels being very different. In the end it was no way
in hell should anyone do this. I'm sorry I can't quote the article as I
have been going through a lot of the old magazines that I have just
acquired.
lg
no neat sig line

"Grant Erwin" wrote in message
...
Now that I'm familiar with how to remove a propane tank valve, what if
I filled the tank about halfway with water, plumbed in regular black pipe
plumbing with a sturdy tee with blowoff valve set for like 200 psi and
a beefy gate valve, and set it on my outdoor propane burner (for deepfat
turkey frying) to generate steam for steam cleaning? The tank's supposed
to be good to 250 psi. Could this generate enough steam to do anything
useful? Steam whistle at a logging show? Anything?

GWE
on a propane tank binge

larry g wrote:

One of the model engineering magazines, HSM I think, had an letter from a
boiler inspector about this very subject. He went on about pressure vessels
and heated pressure vessels being very different. In the end it was no way
in hell should anyone do this. I'm sorry I can't quote the article as I
have been going through a lot of the old magazines that I have just
acquired.

Hmm. Often when someone from an industry whose revenue source depends on
scarcity says "oh no you surely cannot do that" what it really means is
"oh my if everyone did that I'd be out of work". I vaguely remember the
letter, probably was HSM. I'd welcome it if anyone knows which -- since 1982
there have been over 135 issues, that's a LOT of reading.

I'll keep it in mind anyway.

I thought of yet another use, this one no one would complain about. Leave
the ring on the bottom, cut the top off so the walls are still vertical but
as tall as possible, clean it out. Then use it with lye, TSP or dishwashing
detergent and small-medium parts over outdoor burner for homemade "hot tank"
cleaning. This will remove paint from many difficult-to-clean items. The
toughest one I did was the carburetor from an outboard motor. I took the
carburetor in, cleaned, to buy some parts for it and the parts guy called
his buds over and they all said they'd never ever seen a Tecumseh carb
that clean.

GWE

"Grant Erwin" wrote in message
...
Now that I'm familiar with how to remove a propane tank valve, what if
I filled the tank about halfway with water, plumbed in regular black pipe
plumbing with a sturdy tee with blowoff valve set for like 200 psi and
a beefy gate valve, and set it on my outdoor propane burner (for deepfat
turkey frying) to generate steam for steam cleaning? The tank's supposed
to be good to 250 psi. Could this generate enough steam to do anything
useful? Steam whistle at a logging show? Anything?

GWE
on a propane tank binge

Sounds like a possible Darwin winner to me!
Greg

Greg O wrote:

"Grant Erwin" wrote in message
...

Now that I'm familiar with how to remove a propane tank valve, what if
I filled the tank about halfway with water, plumbed in regular black pipe
plumbing with a sturdy tee with blowoff valve set for like 200 psi and
a beefy gate valve, and set it on my outdoor propane burner (for deepfat
turkey frying) to generate steam for steam cleaning? The tank's supposed
to be good to 250 psi. Could this generate enough steam to do anything
useful? Steam whistle at a logging show? Anything?

GWE
on a propane tank binge


Sounds like a possible Darwin winner to me!
Greg

Far too late for that. My genes are already distributed. It might keep the
propane tank from reproducing, though! :-)

GWE

Grant Erwin wrote:
larry g wrote:

One of the model engineering magazines, HSM I think, had an letter from a
boiler inspector about this very subject. He went on about pressure vessels
and heated pressure vessels being very different. In the end it was no way
in hell should anyone do this. I'm sorry I can't quote the article as I
have been going through a lot of the old magazines that I have just
acquired.

Hmm. Often when someone from an industry whose revenue source depends on
scarcity says "oh no you surely cannot do that" what it really means is
"oh my if everyone did that I'd be out of work". I vaguely remember the
letter, probably was HSM. I'd welcome it if anyone knows which -- since 1982
there have been over 135 issues, that's a LOT of reading.

Practically all the heated boiler/steam legislation is there because
people have regularly killed themselves with things they thought would
be fine.

I hesitate to jump in here as my knowledge of the subject is limited to
reading, but IIRC the problem lies in the superheated water in the
container. The pressure allows the water to be heated to well above boiling
point at atmospheric pressure. When you release the pressure as in opening
the steamcleaner valve, all the water can now turn to steam very rapidly.
If your popoff valve does not have sufficient capacity to dump the excess
pressure fast enough the vessel can become overpressured and turn into a
bomb. Seems there was also a greater problem as the water level gets down,
the flash over can occure more rapidly.
Other than that I am all ready to go fire up the crab cooker and stick a
propane tank full of water on it to see how well it works
Glenn
"Ian Stirling" wrote in message
...
Grant Erwin wrote:
larry g wrote:

One of the model engineering magazines, HSM I think, had an letter from
a
boiler inspector about this very subject. He went on about pressure
vessels
and heated pressure vessels being very different. In the end it was no
way
in hell should anyone do this. I'm sorry I can't quote the article as I
have been going through a lot of the old magazines that I have just
acquired.

Hmm. Often when someone from an industry whose revenue source depends on
scarcity says "oh no you surely cannot do that" what it really means is
"oh my if everyone did that I'd be out of work". I vaguely remember the
letter, probably was HSM. I'd welcome it if anyone knows which -- since
1982
there have been over 135 issues, that's a LOT of reading.

Practically all the heated boiler/steam legislation is there because
people have regularly killed themselves with things they thought would
be fine.

In article , Grant Erwin says...

Hmm. Often when someone from an industry whose revenue source depends on
scarcity says "oh no you surely cannot do that" what it really means is
"oh my if everyone did that I'd be out of work". I vaguely remember the
letter, probably was HSM. I'd welcome it if anyone knows which -- since 1982
there have been over 135 issues, that's a LOT of reading.

If you do what you are proposing, you are making a boiler.

The requirements for boiler blow-offs are different than
ordinary pressure vessels, and you should understand the
differences before you put it to work, and see that you
have followed the requirements.

I seem to recall a boiler explosion in a vintage tractor
at a farm fair recently that killed a number of people.

It was a crown sheet explosion. Apparently when a boiler
breaks open, the pressure lowers rapidly which causes the
liquid remaining in teh boiler to flash to steam.

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================

jim rozen wrote:
In article , Grant Erwin says...

Hmm. Often when someone from an industry whose revenue source depends on
scarcity says "oh no you surely cannot do that" what it really means is
"oh my if everyone did that I'd be out of work". I vaguely remember the
letter, probably was HSM. I'd welcome it if anyone knows which -- since 1982
there have been over 135 issues, that's a LOT of reading.

If you do what you are proposing, you are making a boiler.

The requirements for boiler blow-offs are different than
ordinary pressure vessels, and you should understand the
differences before you put it to work, and see that you
have followed the requirements.

I seem to recall a boiler explosion in a vintage tractor
at a farm fair recently that killed a number of people.

AIUI, the guy had also failed to maintain it to such a degree
that 3 independant safety systems failed.

On Sat, 22 Jan 2005 12:00:58 -0800, Grant Erwin
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

But are you _progeny_ going to be far enough away? G

Far too late for that. My genes are already distributed. It might keep the
propane tank from reproducing, though! :-)

GWE

I hesitate to jump in here as my knowledge of the subject is limited to
reading, but IIRC the problem lies in the superheated water in the
container. The pressure allows the water to be heated to well above boiling
point at atmospheric pressure. When you release the pressure as in opening
the steamcleaner valve, all the water can now turn to steam very rapidly.
If your popoff valve does not have sufficient capacity to dump the excess
pressure fast enough the vessel can become overpressured and turn into a
bomb. Seems there was also a greater problem as the water level gets down,
the flash over can occure more rapidly.
Other than that I am all ready to go fire up the crab cooker and stick a
propane tank full of water on it to see how well it works
Glenn
"Ian Stirling" wrote in message
...
Grant Erwin wrote:
larry g wrote:

One of the model engineering magazines, HSM I think, had an letter from
a
boiler inspector about this very subject. He went on about pressure
vessels
and heated pressure vessels being very different. In the end it was no
way
in hell should anyone do this. I'm sorry I can't quote the article as I
have been going through a lot of the old magazines that I have just
acquired.

Hmm. Often when someone from an industry whose revenue source depends on
scarcity says "oh no you surely cannot do that" what it really means is
"oh my if everyone did that I'd be out of work". I vaguely remember the
letter, probably was HSM. I'd welcome it if anyone knows which -- since
1982
there have been over 135 issues, that's a LOT of reading.

Practically all the heated boiler/steam legislation is there because
people have regularly killed themselves with things they thought would
be fine.



you all do realize that a simple garden hose and nozzle attached to the drain
valve on your water heater is all the steam cleaning you will ever need to use.
When I hear the term superheated steam I wonder if you all are familiar with
boiler technology and uses/ makeing of dry steam. you aint gonna accomplish
that with a lil cooker and an old propane tank. you would be missing the
internal firebox featuring muliple steam generation tubes. The presureized and
regulated fuel oil header system with throttles and burner barrels. The forced
draft blowers required to move enough combustion air to the fire box to
generate a signifigant volume of steam top be more than slighjtly useful. and
last byt not least., in making superheated dry steam you need cyclone
separetors to rapidly change direction of the water vapor leaving your
firesides, thus droping any moisture out and back down to the generation tubes
to be flashed again to vapor. Complicated mess really. sperheated and dry steam
refer to the product of a 1200 lb psig dry steam d type boiler plant , like on
ship board.

of course you could just generate 150 lbs aux steam , for a degreasing wand,
with out much more danger than using a pressure cooker. Still, the garden hose
is easier, imho
MLM

jim rozen wrote:

In article , Grant Erwin says...


Hmm. Often when someone from an industry whose revenue source depends on
scarcity says "oh no you surely cannot do that" what it really means is
"oh my if everyone did that I'd be out of work". I vaguely remember the
letter, probably was HSM. I'd welcome it if anyone knows which -- since 1982
there have been over 135 issues, that's a LOT of reading.


If you do what you are proposing, you are making a boiler.

The requirements for boiler blow-offs are different than
ordinary pressure vessels, and you should understand the
differences before you put it to work, and see that you
have followed the requirements.

I seem to recall a boiler explosion in a vintage tractor
at a farm fair recently that killed a number of people.

It was a crown sheet explosion. Apparently when a boiler
breaks open, the pressure lowers rapidly which causes the
liquid remaining in teh boiler to flash to steam.

A little more detail - if you let the water drop
very low and the tractor is standing still, it's
possible for the crown sheet to get red hot even
though there's still some water in the boiler.
As soon as the engine lurches forward, the the
water splashes on the crown sheet and flashes
to steam. No safety valve can vent the pressure
surge in time, not to mention the stresses on the
crown sheet from the temperature changes.

The engine in Ohio did have a very erroded crown
sheet that contributed to the explosion, but I
also suspect there was operator error.

The first rule of operating those old engines
is to always keep plenty of water in the boiler.


Jim

I missed the staff meeting but the minutes show "Glenn"
wrote back on Sat, 22 Jan 2005 16:15:27 -0800 in
rec.crafts.metalworking :
I hesitate to jump in here as my knowledge of the subject is limited to
reading, but IIRC the problem lies in the superheated water in the
container. The pressure allows the water to be heated to well above boiling
point at atmospheric pressure. When you release the pressure as in opening
the steamcleaner valve, all the water can now turn to steam very rapidly.
If your popoff valve does not have sufficient capacity to dump the excess
pressure fast enough the vessel can become overpressured and turn into a
bomb. Seems there was also a greater problem as the water level gets down,
the flash over can occure more rapidly.

For the "Rube Goldbergs" among us, it shouldn't be "too difficult" to
rig a water quench on the steam tank. That is, when the "Oh ****"
pressure valve cuts loose, it trips water reserve, which floods around the
boiler, which "should" soak up heat from the boiler, and hopefully lower
the temp enough to keep the superheated water from trying to become steam.
Or just lower it back to "really hot water".

What comes to mind is a kind of jacket around the boiler, with at least
an equal capacity to the boiler. Normally it is empty, but to shut things
down, you dump water into it and let nature take its course. Hmmm, now I'm
going to be up all night pondering this.


--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."

pyotr filipivich wrote:
I missed the staff meeting but the minutes show "Glenn"
wrote back on Sat, 22 Jan 2005 16:15:27 -0800 in
rec.crafts.metalworking :

I hesitate to jump in here as my knowledge of the subject is limited to
reading, but IIRC the problem lies in the superheated water in the
container. The pressure allows the water to be heated to well above boiling
point at atmospheric pressure. When you release the pressure as in opening
the steamcleaner valve, all the water can now turn to steam very rapidly.
If your popoff valve does not have sufficient capacity to dump the excess
pressure fast enough the vessel can become overpressured and turn into a
bomb. Seems there was also a greater problem as the water level gets down,
the flash over can occure more rapidly.


For the "Rube Goldbergs" among us, it shouldn't be "too difficult" to
rig a water quench on the steam tank. That is, when the "Oh ****"
pressure valve cuts loose, it trips water reserve, which floods around the
boiler, which "should" soak up heat from the boiler, and hopefully lower
the temp enough to keep the superheated water from trying to become steam.
Or just lower it back to "really hot water".

What comes to mind is a kind of jacket around the boiler, with at least
an equal capacity to the boiler. Normally it is empty, but to shut things
down, you dump water into it and let nature take its course. Hmmm, now I'm
going to be up all night pondering this.

Even better might be a "pressurizer" tank such is
used with nuclear reactors. A large tank of hot
water located above the boiler and at a slightly
higher pressure. It would supply makeup water at
the same rate as is being consumed by steam
production.

--Coles used to sell a pressurized diaphragm valve for a fuel
system, set up so that if pressure fell in the boiler it automatically
shut off the fuel supply. What more does one need?

--
"Steamboat Ed" Haas : Heartily sick of
Hacking the Trailing Edge! : "oldies" stations!
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

pyotr filipivich wrote:
I missed the staff meeting but the minutes show "Glenn"
wrote back on Sat, 22 Jan 2005 16:15:27 -0800 in
rec.crafts.metalworking :
I hesitate to jump in here as my knowledge of the subject is limited to
reading, but IIRC the problem lies in the superheated water in the
container. The pressure allows the water to be heated to well above boiling
point at atmospheric pressure. When you release the pressure as in opening
the steamcleaner valve, all the water can now turn to steam very rapidly.
If your popoff valve does not have sufficient capacity to dump the excess
pressure fast enough the vessel can become overpressured and turn into a
bomb. Seems there was also a greater problem as the water level gets down,
the flash over can occure more rapidly.

For the "Rube Goldbergs" among us, it shouldn't be "too difficult" to
rig a water quench on the steam tank. That is, when the "Oh ****"
pressure valve cuts loose, it trips water reserve, which floods around the
boiler, which "should" soak up heat from the boiler, and hopefully lower
the temp enough to keep the superheated water from trying to become steam.
Or just lower it back to "really hot water".

Me, I'd be tempted to dig a biggish hole, and place boiler inside.

In article , pyotr filipivich
says...

For the "Rube Goldbergs" among us, it shouldn't be "too difficult" to
rig a water quench on the steam tank.

Didn't work at Three Mile Island....

:^)

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================

jim rozen wrote:
In article , pyotr filipivich
says...


For the "Rube Goldbergs" among us, it shouldn't be "too difficult" to
rig a water quench on the steam tank.


Didn't work at Three Mile Island....

It would have if they had closed the relief valve
and took a look at their steam tables...

On Wed, 26 Jan 2005 07:41:44 GMT, pyotr filipivich
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

It all starts sounding as if we could simply stay away form these
friggin boilers....

I missed the staff meeting but the minutes show "Glenn"
wrote back on Sat, 22 Jan 2005 16:15:27 -0800 in
rec.crafts.metalworking :

In article , Jim Stewart says...

Didn't work at Three Mile Island....

It would have if they had closed the relief valve
and took a look at their steam tables...

The pressurizer level indicator was hidden behind a huge
bunch of stuff, most of which they didn't need to look
at.

But your point is well taken - if they had done a
bunch of different stuff, the core would not have
slumped.

But they didn't. And it did.

Therefore the secondary cooling system did fail. It
failed because it was turned off, granted. Because
of the lack of appropriate human engineering it did not
work.

The same problem could crop up with a steam boiler
secondary cooling system.

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================

Jim Stewart wrote:

pyotr filipivich wrote:

I missed the staff meeting but the minutes show "Glenn"
wrote back on Sat, 22 Jan 2005 16:15:27 -0800 in
rec.crafts.metalworking :

I hesitate to jump in here as my knowledge of the subject is limited
to reading, but IIRC the problem lies in the superheated water in
the container. The pressure allows the water to be heated to well
above boiling point at atmospheric pressure. When you release the
pressure as in opening the steamcleaner valve, all the water can now
turn to steam very rapidly. If your popoff valve does not have
sufficient capacity to dump the excess pressure fast enough the
vessel can become overpressured and turn into a bomb. Seems there
was also a greater problem as the water level gets down, the flash
over can occure more rapidly.



For the "Rube Goldbergs" among us, it shouldn't be "too
difficult" to
rig a water quench on the steam tank. That is, when the "Oh ****"
pressure valve cuts loose, it trips water reserve, which floods
around the
boiler, which "should" soak up heat from the boiler, and hopefully lower
the temp enough to keep the superheated water from trying to become
steam.
Or just lower it back to "really hot water".

What comes to mind is a kind of jacket around the boiler, with at
least
an equal capacity to the boiler. Normally it is empty, but to shut
things
down, you dump water into it and let nature take its course. Hmmm,
now I'm
going to be up all night pondering this.


Even better might be a "pressurizer" tank such is
used with nuclear reactors. A large tank of hot
water located above the boiler and at a slightly
higher pressure. It would supply makeup water at
the same rate as is being consumed by steam
production.

Then to avoid the pressurizer tank having a problem, you would want an
even higher pressure tank plumbed to supply makeup water to your
pressurizer tank...I think this needs further consideration.

Steve

I missed the staff meeting but the minutes show steamer
wrote back on Wed, 26 Jan 2005 17:36:19 GMT in rec.crafts.metalworking :
--Coles used to sell a pressurized diaphragm valve for a fuel
system, set up so that if pressure fell in the boiler it automatically
shut off the fuel supply. What more does one need?

Some way to cool the boiler. More importantly, the water in the
boiler, similar to putting an ice cube in the soup to keep it from boiling
over while you turn the stove down.

What I'm thinking about is when you get that run away situation - I may
be trying to prepare for the one in a million cases where the pressure
relief isn't enough and the boiler would explode anyway. Rapid cooling of
the water to below boiling point. Which is also a function of pressure,
so... doesn't have to be much. [Of course, as the wizards all know, 1 in a
million event tend to happen 9 out of 10 times. HT to Terry Prachert.]

--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."

I missed the staff meeting but the minutes show jim rozen
wrote back on 26 Jan 2005 11:10:38 -0800 in
rec.crafts.metalworking :
In article , pyotr filipivich
says...

For the "Rube Goldbergs" among us, it shouldn't be "too difficult" to
rig a water quench on the steam tank.

Didn't work at Three Mile Island....

:^)

Yeah, but the containment wall held. If there is one thing engineers
can do after five thousand years, is build a wall. :-)

tschus
pyotr

--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."

I missed the staff meeting but the minutes show Ian Stirling
wrote back on 26 Jan 2005 18:50:11 GMT in
rec.crafts.metalworking :
pyotr filipivich wrote:
I missed the staff meeting but the minutes show "Glenn"
wrote back on Sat, 22 Jan 2005 16:15:27 -0800 in
rec.crafts.metalworking :
I hesitate to jump in here as my knowledge of the subject is limited to
reading, but IIRC the problem lies in the superheated water in the
container. The pressure allows the water to be heated to well above boiling
point at atmospheric pressure. When you release the pressure as in opening
the steamcleaner valve, all the water can now turn to steam very rapidly.
If your popoff valve does not have sufficient capacity to dump the excess
pressure fast enough the vessel can become overpressured and turn into a
bomb. Seems there was also a greater problem as the water level gets down,
the flash over can occure more rapidly.

For the "Rube Goldbergs" among us, it shouldn't be "too difficult" to
rig a water quench on the steam tank. That is, when the "Oh ****"
pressure valve cuts loose, it trips water reserve, which floods around the
boiler, which "should" soak up heat from the boiler, and hopefully lower
the temp enough to keep the superheated water from trying to become steam.
Or just lower it back to "really hot water".

Me, I'd be tempted to dig a biggish hole, and place boiler inside.

Good idea too. Tends to channel any explosion "up and away".

Or you could take a tip from the gun powder mills or old powder
magazines. Three stout walls and a flimsy fourth and roof. That way, if
the mill blew up, the blast goes "that way" in stead off "everywhere."

--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."

The whole boiler idea is a bad one. They store substantial amounts of
energy,and even a small one would destroy the average garage, not to mention
anyone standing nearby. There are codes to design boilers.( I think the
American on is ASME section VII) You might read that before you go too far
with your design. Industrial boilers have two safety valves and a control
system to keep the pressure constant as well as a pressure switch which
shuts off the gas or oil supply in the event of the boiler going over its
safe operating pressure. The "Scram" system would probably CAUSE an
explosion as the sudden thermal stresses would cause a fracture somewhere
that would propagate at the speed of sound in steel.


Tom

"pyotr filipivich" wrote in message
...
I missed the staff meeting but the minutes show "Glenn"
wrote back on Sat, 22 Jan 2005 16:15:27 -0800 in
rec.crafts.metalworking :
I hesitate to jump in here as my knowledge of the subject is limited to
reading, but IIRC the problem lies in the superheated water in the
container. The pressure allows the water to be heated to well above
boiling
point at atmospheric pressure. When you release the pressure as in
opening
the steamcleaner valve, all the water can now turn to steam very rapidly.
If your popoff valve does not have sufficient capacity to dump the excess
pressure fast enough the vessel can become overpressured and turn into a
bomb. Seems there was also a greater problem as the water level gets
down,
the flash over can occure more rapidly.

For the "Rube Goldbergs" among us, it shouldn't be "too difficult" to
rig a water quench on the steam tank. That is, when the "Oh ****"
pressure valve cuts loose, it trips water reserve, which floods around the
boiler, which "should" soak up heat from the boiler, and hopefully lower
the temp enough to keep the superheated water from trying to become steam.
Or just lower it back to "really hot water".

What comes to mind is a kind of jacket around the boiler, with at least
an equal capacity to the boiler. Normally it is empty, but to shut things
down, you dump water into it and let nature take its course. Hmmm, now
I'm
going to be up all night pondering this.


--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."

On Thu, 27 Jan 2005 10:06:13 +1100, "Tom Miller"
wrote:

The whole boiler idea is a bad one. They store substantial amounts of
energy,and even a small one would destroy the average garage, not to mention
anyone standing nearby. There are codes to design boilers.( I think the
American on is ASME section VII) You might read that before you go too far
with your design. Industrial boilers have two safety valves and a control
system to keep the pressure constant as well as a pressure switch which
shuts off the gas or oil supply in the event of the boiler going over its
safe operating pressure. The "Scram" system would probably CAUSE an
explosion as the sudden thermal stresses would cause a fracture somewhere
that would propagate at the speed of sound in steel.


Tom

"pyotr filipivich" wrote in message
.. .
snip

A BLEVE (Boiling Liquid Expanding Vapor Explosion) is a very fast
event, probably no more than a few milliseconds. In that time frame,
anything the size of a propane tank could be considered adiabatic.
You're not going to move a useful amount of heat other than through
the rip in the shell as the water flashes to steam instantly. If it
were cooled starting while it was still far enough below its rupture
pressure/temp, it might work, but there's no way to know for sure at
what pressure rupture will occur.

At a plant that was purchased by the corporation I work for, for years
a ruptured vessel was kept on display. An engineer in the previous
outfit had been in the habit of venting runaway reactions by running
to the reactor and loosening bolts on the manway to vent the reactor.
After a few times where he got lucky, the inevitable happened, and he
was sprayed across the landscape when the manway blew just as he got
there.

The only rational response would have been running away.

Pete Keillor

On Thu, 27 Jan 2005 10:06:13 +1100, "Tom Miller"
wrote:

The whole boiler idea is a bad one. They store substantial amounts of
energy,and even a small one would destroy the average garage, not to mention
anyone standing nearby. There are codes to design boilers.( I think the
American on is ASME section VII) You might read that before you go too far
with your design. Industrial boilers have two safety valves and a control
system to keep the pressure constant as well as a pressure switch which
shuts off the gas or oil supply in the event of the boiler going over its
safe operating pressure. The "Scram" system would probably CAUSE an
explosion as the sudden thermal stresses would cause a fracture somewhere
that would propagate at the speed of sound in steel.


Tom

"pyotr filipivich" wrote in message
.. .
I missed the staff meeting but the minutes show "Glenn"
wrote back on Sat, 22 Jan 2005 16:15:27 -0800 in
rec.crafts.metalworking :
I hesitate to jump in here as my knowledge of the subject is limited to
reading, but IIRC the problem lies in the superheated water in the
container. The pressure allows the water to be heated to well above
boiling
point at atmospheric pressure. When you release the pressure as in
opening
the steamcleaner valve, all the water can now turn to steam very rapidly.
If your popoff valve does not have sufficient capacity to dump the excess
pressure fast enough the vessel can become overpressured and turn into a
bomb. Seems there was also a greater problem as the water level gets
down,
the flash over can occure more rapidly.

For the "Rube Goldbergs" among us, it shouldn't be "too difficult" to
rig a water quench on the steam tank. That is, when the "Oh ****"
pressure valve cuts loose, it trips water reserve, which floods around the
boiler, which "should" soak up heat from the boiler, and hopefully lower
the temp enough to keep the superheated water from trying to become steam.
Or just lower it back to "really hot water".

What comes to mind is a kind of jacket around the boiler, with at least
an equal capacity to the boiler. Normally it is empty, but to shut things
down, you dump water into it and let nature take its course. Hmmm, now
I'm
going to be up all night pondering this.


--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."

All this talk about boilers is why I decided not to make a steam
engine. The boilers just require too much vigilance. Which I'm not
prepared to be. Vigilant, that is.
ERS

On 26 Jan 2005 14:21:16 -0800, jim rozen
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

Somebody here has as sig line about foolproof and bigger fools....
G

The same problem could crop up with a steam boiler
secondary cooling system.

Jim

In article , pyotr filipivich
says...

Didn't work at Three Mile Island....

:^)

Yeah, but the containment wall held.

No, the *secondary* containment held. The
fuel cladding melted and failed, the core slumped
to the bottom of the pressure vessel.

And during the event, the pressurizer relief valve
was dumping primary loop coolant into the reactor
building sump, which overflowed, which then was
then automatically pumped into another building,
where *that* tank overflowed.

In that sense the primary containment of the
reactor was breeched badly.

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================

I missed the staff meeting but the minutes show jim rozen
wrote back on 26 Jan 2005 14:21:16 -0800 in
rec.crafts.metalworking :
In article , Jim Stewart says...

Didn't work at Three Mile Island....

It would have if they had closed the relief valve
and took a look at their steam tables...

The pressurizer level indicator was hidden behind a huge
bunch of stuff, most of which they didn't need to look
at.

If I recall correctly, the control levers had been replaced with beer
tap levers. Seems that the issued levers were all alike, and you had to
look to be sure you had the correct one.

But your point is well taken - if they had done a
bunch of different stuff, the core would not have
slumped.

But they didn't. And it did.

Therefore the secondary cooling system did fail. It
failed because it was turned off, granted. Because
of the lack of appropriate human engineering it did not
work.

Ranging from using the same warning horn for everything. How can you
tell the difference between "oh my god it's gonna blow" from "somebody let
the coffee pot run dry" if you use the same klaxon for both?

Etc, etc.

It wasn't as if we didn't have experience with using all the human
senses to prevent accidents. The USAAF made the "wheels down" knob feel
like a wheel, while the "flaps down" knob feel like a little wing. Having
the gauges pointed the same direction when things were good, makes
isolating a problem a lot easier. Especially in multi engine aircraft.
Etc.


The same problem could crop up with a steam boiler
secondary cooling system.

Well, yeah.

But you can think it through and figure out where the problems are.

ALSO, and just as important, you can see what has gone before, to
discover what sort of failures had occurred and their causes. E.g. the top
sheet flashing problem.

tschus
pyotr



--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."

Eric R Snow wrote:
On Thu, 27 Jan 2005 10:06:13 +1100, "Tom Miller"
The whole boiler idea is a bad one. They store substantial amounts
of energy,and even a small one would destroy the average garage,
not to mention anyone standing nearby.

All this talk about boilers is why I decided not to make a steam
engine. The boilers just require too much vigilance. Which I'm not
prepared to be. Vigilant, that is.

Just have to respect what can happen. Afterall, folks are killed
by water heaters when safeties fail.

Why not look into flash boilers. The tubes don't store as much
energy to be converted into a bomb should things go badly.
If you are stuck on using that old propane tank, just cut it and
line it with brick for the combustion chamber. Just don't
use it for a pressure vessel.
How much steam did your planned engine require?

**
mike
**

How much steam did your planned engine require?

**
mike
**

I was the original poster. I have never planned to build a steam engine.
I merely noticed that once you removed the tank valve and cleaned out the
methyl mercaptan that an old propane tank looked like you could just put
water into the tank and a steam valve at the top (it's just 3/4" NPT) and
put it on a big propane outdoor burner. So I wondered publicly if it would
work and from the response it sure looks like it wouldn't!!

GWE

--OK for this you need to talk to the SACA West gang. Speicfically
the guy (name escapes me at the moment) who modified a VW engine and put
on his own variation of a spinning cup burner. IIRC the way he's got it
set up is full fire actually heats the coil boiler more than it needs, so
he's got a controlled cold water intake to keep pressure at a set level.
Neat car; got to ride in it maybe 10-15 yrs back. He turned the key to
start it (needs an electric starter because the valves only admit steam
for something like 7 percent of a rotation), waited maybe 10 seconds while
I watched the pressure gauge climb and climb and we were off.
--Last guy in that group for whom I had email is Ken Kowal; last
address:
--Also try Allen Frisbie who lurks here; IIRC he's in touch with
that group.

--
"Steamboat Ed" Haas : Heartily sick of
Hacking the Trailing Edge! : "oldies" stations!
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

--Remembered the guy's name: Pete Barrett. Email me and I'll give
you his phone number.

--
"Steamboat Ed" Haas : Heartily sick of
Hacking the Trailing Edge! : "oldies" stations!
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

OK, let's go in a slightly different direction. To summarize, I proposed
putting a water tank over a burner, said water tank having a steam valve
on top. As I understood it, this is dangerous because

a) when the valve is opened and pressure is lowered a catastrophic amount
of water will instantly convert to steam

b) if the tank gets real hot somewhere and is sloshed such that water hits
the hot spot, a catastrophic amount of water will instantly convert to steam

Did I get those right?

So how *do* you build a boiler so that neither of these terrible things happen?
In plain simple words, please, no math allowed. Imagine I'm a bright 10th
grade physics student, for example.

I've looked at boiler designs and they have a firebox which is in thermal
contact with boiler tubes which contain water which is converted to steam.
How does this differ from a water tank over a burner flame?

GWE

I missed the staff meeting but the minutes show Grant Erwin
wrote back on Fri, 28 Jan 2005 14:02:18 -0800 in
rec.crafts.metalworking :
OK, let's go in a slightly different direction. To summarize, I proposed
putting a water tank over a burner, said water tank having a steam valve
on top. As I understood it, this is dangerous because

a) when the valve is opened and pressure is lowered a catastrophic amount
of water will instantly convert to steam

b) if the tank gets real hot somewhere and is sloshed such that water hits
the hot spot, a catastrophic amount of water will instantly convert to steam

Did I get those right?

Sounds right. All though in a), it is if the pressure drop is too
great, such that the temperature of the water is above the boiling point
_at that pressure_. Not having a steam table handy, I will make it up as I
go: Water normally boils at 100 petrograds, and one lungfull of pressure,
However if you raise the pressure to 2 lungs, then water boils at 150
petrograds. So now you have a pot of water at 150 petrograds, and
everything is happy. Steam floats around, "choo-choo" and da kine. The
pressure cycles between 1.95 and 2.0 lungfulls and everything is "cool".
Then some fool (not you, some other fool) pops the valve and the pressure
drops to 1.8 lungfulls, and the water, which formerly was below the boiling
point is now above the boiling point, and wants to join in the steam biz,
expanding 400 fold in the process. Big spike in the pressure. If the
boiler can hold the 3 lung transitory pressure while things settle down,
well and good. If not, and say the safety vale pops off - bad things
happen. Pressure equalizes inside and out at 1 lungfull. Well, it would,
if the water temperature was 100 petrograds, but all that water is fifty
petrograds above the boiling point of water at 1 lung pressure. Weeee!
Water flashing into steam all over the place, rushing for that little hole.
IF the hole isn't big enough, impatient steam molecules start to back up,
pressure rises and a new hole is made. Catastrophically.
And then all that 150 petrograd steam starts to cool and transfer heat
as it drops to 100 petrograds, condenses (transferring more heat) and then
drops to the "ambient" temperature. Lot of hurt in that alone.

So how *do* you build a boiler so that neither of these terrible things happen?
In plain simple words, please, no math allowed. Imagine I'm a bright 10th
grade physics student, for example.

1) Over build. Build that bad boy so it will hold 3 "lungfulls" of
pressure, then put a gage which reads "2.01 Lungfulls" as Max "never
exceed", put a pop valve set to 2.5 lungfulls, then cross your fingers and
pray for success. In other words, whatever steam pressure you want should
be a fraction of the pressure the boiler can handle. Then inspect for weak
spots, regularly. (I hope that isn't too much math :-) )
2) make sure there is plenty of water to cover the firebox, especially
the "flame crown" where the fire touches the metal.

I've looked at boiler designs and they have a firebox which is in thermal
contact with boiler tubes which contain water which is converted to steam.
How does this differ from a water tank over a burner flame?

More surface area gets heated, the water heats faster, you have power
sooner. I've seen two basic designs: one with tubes of water in a firebox,
the other with Tubes from the fire box through the water. YMMV, a lot of
plumbing either way.

Back in "zee old country," we had flash heaters. rather than keep a
thirty gallon tank of water hot all the time, when you turned on the tap,
the flash heater would light up (bottled butane gas) and heat a number of
coils with the water flowing through them, and you had hot water which only
had to travel a couple meters from the heater to the tap, rather than
through the whole house.

Same principle.
tschus
pyotr

--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."