looking for advice on a boiler project

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timo_gross

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Not a good idea to wait until no steam comes out. You could end up warping the metal and destroy it. Low water cut off is what you need.
HMEL


Hello,

... obviously a water glas should be made, it will eliminate the guessing.

Greetings Timo
 
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As "lost" within the garbage I wrote above. This is Good for Timo's use at NWP of 3 bar = 45psi. The steam delivery depends on the heat source, and actual pressure and demand from the engine. AND it depends on having a continuous water supply, occasional supply, or NO supply. The bushes are fitted in the boiler end ready for the water gauge, water feed, etc. Just needs Timo to make them.
Cheers, K2
 
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No not really collected any hard fact numbers, it is sufficient to drive a small thing like an Elmers Engines, or the Gerries Beam Engine.
Both engines run on compressed air well below 1 bar.
I would guess it also depends very much on the heat source and the insulation. (which are both not finalized yet)
I think this is not the best boiler for a "workhorse" engine, but good enough for "my toy" enginges they do not have to do work.
The running time is about 10 maybe 20 min and it stays well below 3 bar. (I get the safety valve only to open when I close the steam valve and wait a little)
Starting the heating with around 200 ml of Water. The total Volume as per CAD program is 290 ml.
I think the steam was fairly wet coming out of the boiler, some kind of overheating would be a good idea.

Maybe in the final setup I take the steam line once through the flame.


I hope that helps.

Greetings Timo
Hi Timo, you have got it right. Insulation can make a huge difference to steam delivery, as you minimise wastage (lost) heat. Also, the water quantity is almost immaterial, as in principle, for constant running of any engine, you want to keep the water within limits.
A dryer/ superheater can be a horseshoe loop thought the water tubes and can be very effective at making the engine run with less water exhausted in the wet steam.
Enjoy!
K2
 
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Just for anyone interested in a bit of boiler design, I have done a study of the design by Michel Niggel, and the mods proposed by Timo Gros. (I may seem "sad" to some, but I enjoy it!). My basis is the ASME regulation limits, which may or may not have been appropriate for the original MN design, but I think should be applied to any changes of design. I think it is OK to ASME. (As expected).
I have based the design changes on the information from Timo as earlier in this thread.
(Moderator: if inappropriate for the original thread raised by Henry Banjo, this can be deleted. - K2).
Henry, I had a thought... the rectangular "boiler" you are studying may be the casing that contains the burning fuel, not the water/steam. That would make sense of the "26 thou thick ". The water/steam (I would expect) should be in tubes inside this "tank".
The boiler being made by Timo should easily power the engines you described, and is a good safe design. - Hope that helps?
Cheers!
K2
 

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timo_gross

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....
(I may seem "sad" to some, but I enjoy it!) Hope that helps?
Cheers!
K2....
Hello,
I think we can be grateful for this kind of constructive feedback. I hope it will help maybe someone searching for the first project.
I did not start with the water level glas, because I have other "higher" priority work respective fun stuff in progress.

Greetings Timo
 
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