Engine Compartment Fire Extinquishing System

[JOHN COOKSON]

Pump the air out of the space between the inner and outer piping and seal it off. You'll have a thermos. Betcha the outer layer will stay cool then.

TRUE GRIT

[romantic comedy]

Don, thanks for looking in on us. We always know that you are there!!!

All hail Don, all hail Don!!

Art, the double wall pipe is always custom made.

[hanleyclifford]

From what I'ver read so far the best solution seems to be RC's copper coil but it has to be done right because it is going to be part of the antifreeze loop and must be tight and protected. Therefore the hot section should be wrapped with the usual wrap to create a soft surface. Then the coil should be wrapped around the section as tight as is practical and equipped with appropriate fittings to make up to the antifreeze intake at the pump on one end and the discharge end of the exchanger. I like the Yor Lok style with two compression rings. Finally the coil should be wrapped again. I would recommend going up to 3/8" ID on the copper (1/2" OD).http://www.mcmaster.com/#yor-lok-tube-fittings/=qzqxx1

[ArtJ]

Thanks Hanley

Perhaps if the exhaust is wrapped and the outer coil filled with pumped
water, there wouldn't be a need for as many wraps as Romantic Comedy
has since the inner black iron pipe would be cooled?

[hanleyclifford]

Thanks Hanley

Perhaps if the exhaust is wrapped and the outer coil filled with pumped
water, there wouldn't be a need for as many wraps as Romantic Comedy
has since the inner black iron pipe would be cooled?

Exactly - the purpose of the inner wrap is to create a cushion for the copper and isolate it electrochemically from the iron and protect the copper from vibration.

[romantic comedy]

Hanley, if I think about it, what the tubing is doing, is the same thing that a jacketed system is. if we take it to an extreme, we could solder around the coil, and seal the tubing into a water tight jacket. Then only the ends would need sealing. Water could be introduced, and poof, there you have a jacketed exhaust.

I dont think I would go that far, but it could be possible. The insulation is not necessary in t hat system. some sort of stand offs would need to be fabricated to keep the coil in position.

I used 3/8 soft refrigeration tubing. think I paid 100 for the 110 feet. It bent pretty easily around some pvc. (almost typed PCV, whew!!). The larger tubing might be much more expensive and harder to work around that small diameter. With no insulation, even smaller tubing could be used.

If one was going for this "magic jacket" a small size would be preferable. No water would actually pass thru the tubing. (maybe someone would say that we can use the tube as a jacket and a water heater, lol. just kidding.)

I thought of presenting the idea to the forum, but it seemed so Rube Goldberg, I figured it to be a joke. Now I am thinking again.
this is fun

[hanleyclifford]

What we have so far is a "dry" exchanger, in effect, but the antifreeze has to go thru the tube to make it effective unless you are trying for a "radiant" transfer which is exactly what we are trying to prevent. It's easy to bend the copper; the coil is wound around a pipe locked in a vise, the coil is then slipped over the wrapped (disconnected) hot section. If you are really skillful you wind it tight enough that it must be "unwound" slightly to slip it on and upon release clings to the wrapped hot section nicely.

[romantic comedy]

another quick thought. I think my coil was 4 inches ID. There were places where I had trouble getting it on the black pipe, with the bends.

I was looking at tubing benders, and they were for bigger coils. So I did it the best I could figure.

[hanleyclifford]

No question, a tubing bender would be required but not a big nasty one like what I had to use to bend that 1" stainless for my pulpit - I think a bender like the plumbers and electricians use would be good for this type of job.

[ArtJ]

Could the very small and highly flexible copper tubing that they use for
the refrigerator's water supply be used? We don't need to totally
cool the black Iron, just get it to a manageable temperature.
A proportional valve could be used to send some of the water thru it.

Possible sizes, 1/4, 5/8, 1/2 inch? Could use more turns of a lower
gauge that is easy to coil directly around black pipe without disassembly
possibly?

Regards

Art

[hanleyclifford]

Maybe you should have a conversation with these folks: http://www.coppertubecoils.com/

[hanleyclifford]

This looks very close to what you need: http://www.instructables.com/id/How-...thout-Crushin/

[ArtJ]

A few thoughts have occurred to me:

How would the coil of tubing be kept from blocking up from
salt water contaminants?

What would be the minimum diameter that would allow acceptable
flow and minimize blockage?

How would the pipe be flushed out?

IS IT POSSIBLE TO USE SOMETHING LIKE THE BRAIDED STAINLESS STEEL
HOSES USED FOR HOME CLOTHES WASHER WATER SUPPLIES DIRECTLY-
MINIMIZING OR ELIMINATING THE ISSUE OF COILING COPPER TUBING?

IT WOULD BE OF SUFFICIENT DIAMETER TO ALLOW ADEQUATE COOLING
AND BE EASILY WRAPPED IN SITU (SP?) AROUND THE BLACK IRON
WITHOUT THE PITA OF UNTHREADING AND PROBABLE REBUILDING
OF THE BLACK IRON PIPE.
IT COULD BE EASILY CONNECTED WITH
THREADED HOSE CONNECTIONS AND REMOVED QUICKLY AND EASILY
FOR CLEANING OR REPLACEMENT?

WHAT DO YOU THINK OF THIS GUYS?

BEST REGARDS
ART

[hanleyclifford]

Hi Art - As Neil has pointed out, salt could plug a small copper tube sooner rather than later especially if the volume/velocity is low, and it will be since a diverter valve will be used. I think the coolant has to be antifreeze. The smallest ID I would consider is 1/4" but 3/8" would be way better. I don't know if the braided stainless line can take the temperatures involved here; perhaps some one else has used it this way. I don't think there is any easy fix for this, Art; you (and many others) are dealing with a fundamental design error. In your situation I would pull the section and start over building a hot section with it's own integral exchanger. You might even be able to get a patent - I've never seen one. Regards, Hanley

[ArtJ]

THanks Hanley

IS the intension of double walled ss exhaust pipe to be used with
water or antifreeze?

THe meshed Laundry hose handles hot water . Possible recirculate
back to engine FWC system?