Controlled flash to steam? ( tickling the dragon's balls?)

RickDelta

@Mark Eatherton:
"How does one spin a 20' stick of 2" pipe at 3500 RPM's in the field?"

Can't be done in the field! ...... this is done in the shop!
20'ers spin welded together then coiled into a continuous 5ft diameter rigid coiled pipe.

I have two PVC extruder co's that can "coil" the normally straight lengths of pipe as it is extruded! This would eliminate the "in-shop" spin-welding step all together. The entire extruder master batch would run continuously coiling the rigid PVC while still hot out of the extruder ...... NO joints! one continuous coiled length of pipe of any length desired ..... upto around 10,000ft! : )

RickDelta

Leonard

Carefull with a long pipe, it can whip if gets loose. Stuff coming out the end will act as a rocket, think loose fireman's hoses.

Seen the gas company heat weld 4" plastic pipe in the field....... they used a small generator for power.

Machine gabs both pipes, and lightly presses them to a heated plate to melt ends, then plate is lifted and machine presses ends together till they cool

RickDelta

...... this was my early spin testing of the PVC for destructive weld strength.In the hundreds of samples ...... the pipe breaks, never the welded joint!!

RickDelta

@Leonard:
"Seen the gas company heat weld 4" plastic pipe in the field....... they used a small generator for power.
Machine gabs both pipes, and lightly presses them to a heated plate to melt ends, then plate is lifted and machine presses ends together till they cool"

Yes! ..... but, PVC has a much smaller process window ..... very hard to use this "heat plate" out in the field for PVC. Also, this method creates an inside bead and an outside bead on the pipe joint. Not good thing!
Spin weld makes no bead and is over in 3 seconds!

..... this "bead" adds extra PVC at the joint and stops the pipe from expanding uniformly with the liner pipe (necks down the pipe at the joint)

RickDelta

If I take a very large steam driven turbine electric generator (like ones used in nuclear power plants) pipe the input directly into the ocean and connect the output to a 30 mile high (absolute vacuum of outer space) exhaust pipe ...... free electric? : ) .... or end of the world as we know it? : (

Leonard

Huuuu???

Pressure at bottom of 30 mile high pipe to outer space will be 14.7 psi , IF air is in the pipe.

Maybe less if water vapor is in the pipe. Think water vapor is less dense than air that's what airplane pilot told me once. He said it's less dense so creates less lift when fly thru clouds. Could check the steam tables but I'm going to bed now.

RickDelta

I would think both the outer space end (at absolute vacuum) and the pipe end sitting in the ocean water would be at this absolute vacuum as well (surface water at bottom of pipe sees absolute vacuum = supersteam?)

RickDelta

...... My understanding is that the water in the pipe at sea level would rise up the pipe aprox. 33 ft max. (surrounding 14.7 psi is pushing the water up the pipe) above sea level if the air was removed from inside this pipe exposing the sea water at the 33 ft level in the pipe to absolute vacuum of space .... flashing this water to steam (gas).
I assume the large mass of heat capacity of the ocean would be considered an infinite heat source.

...... probably will need a condensate return line after about 2,000 ft up
: )

Leonard

Condensate return, there is one.....called rain

No difference between a pipe of air extending to outer space and our atmosphere that extends to outer space. Gravity works just as well on the air in both........ making ~ 14.7 psi at sea level in both cases..

......well ok,...... humid air might make slightly less pressure ( ~5% less). Barometer goes down when rainy low pressure weather systems swing by.

At sea level a vacuum can pull water up a pipe ~ 33.9 ft max, actually to be more precise the 14.7 psi pressure differential between top and bottom pushes water up 33.9 ft

Humid air density......Now you got me interested.......so I looked at my weather barometer. Fair weather is ~ 30 inches of mercury , Stormy is 28.5, and Very dry is 30.5.
These correspond to ~ 14.7 psi, 14.0, and 15.0 respectively.
So possibly humid air is less dense than dry air.

I'ld still check the steam tables for density of 100% water vapor at 70 degs,and compare to dry air, since don't know how much thickness of atmosphere varies with weather.

Leonard

Ok adding humidity to air (in atmosphere) does lower the air pressure.

Wieipedia confirms adding water vapor to air lowers it's density.

1/3 of way down in link
https://en.wikipedia.org/wiki/Density_of_air#Humidity_

ratio

Maybe if we primed the pipe with politicians.