# Medium sized monotube boiler



## rangerssteamtoys (Jun 5, 2008)

Since I have my gas steam engine. I need to make a boiler for it, I'm going with a monotube boiler made from 2 coils of 60' 1/2" copper tubing. The outer shell for this will be a small air compressor tank. I need some advice on what to do.












Here is what I need help on.

A feedwater pump, this boiler will be mobile so it cant be a water hose. I was thinking a hand pump converted to mechanical by attaching an eccentric.

A burner, I cant use propane but oil, wood, and any other suggestions are welcome.

I'm not a machinist, and I will need some parts made. Volunteers and any help would be appreciated.

I want to get about 120-150 psi with this setup. So can any one help me?Please mam/sir


----------



## rake60 (Jun 5, 2008)

Home made boilers scare the **** out of me...

I know that hundreds have been built to be perfectly safe and operate flawlessly.
Steam powered an entire era of manufacturing and mining in this country.
Many lives were lost to structural boiler failures in those days.

I've seen insurance photos of the aftermath of tiny 8 ounce toy boiler explosions.
Mangled fingers and disfigured faces caused by a pressure relief valve that had 
corroded shut from the heat of moisture of the steam.
_*It was just a toy!*_

A boiler is a controlled bomb.
It's real easy to lose that control without knowing it has been lost.

_*Let's be CAREFUL out there!*_

OK I'll kick my soap box back under the sofa now...

Rick


----------



## rangerssteamtoys (Jun 5, 2008)

Safey is a BIG thing. Thats why I chose a monotube boiler, instead of a traditional firetube boiler. If the copper pipe fails just a little steam flies everywhere. It beats the heck out of a giant 100-200lb boiler sending shrapnel.

My dad wont let me use a propane burner because it no safe enough. I think that too, the thought of a propane cylinder blowing up scares me.


----------



## rangerssteamtoys (Jun 8, 2008)

PROGRESS!!!!! 

I have got alot done with the shell, heres what I did so far today. 

Finished grinding welds off boiler 
Painted it black 
Ground off the bottom cap 
Pressure washed the inside of the boiler, lots of oil and metal gunk 
Cut a hole for the chimney, Rough at first. 
Smoothed out the hole 
Mounted chimney w/ screws, 
Painted the chimney 
Took it outside for a cleaning test. More on cleaning test after pics  

Its ALOT brighter in real life than in the pics, but self adjusting camera doesnt do it any good. 



















Rough cut hole with a grinder. 










Smoothed out hole with air dremel 










Simple metal drier pipe for chimney. 





Put it on a rolling stand to take it outside, I'm lazy I dont want to carry it that far. 





Me standing beside the boiler for size comparasion. I'm about 5' 5" 





Took it outside and put it on a brick firebox 





Looking down the chimney at the hole, I made the hole small so if I wanted I could make it bigger. 





Thrown together brick firebox 

I will get a fire going later. This is just the outer shell of the boiler, no copper tubing put in yet. I want to burn off all the oil and nasty crud that I didnt get with the pressure washer. Fire pics will be in a few hours,after it cools down a bit.


----------



## ksouers (Jun 8, 2008)

Ranger,
I just read this for the first time.

Steam is very different than air.

As Rick said...

*THIS IS EXTREMELY DANGEROUS!!!!*

120-150 PSI of steam is nothing to mess with! Steam at this pressure has TREMENDOUSLY MORE energy than air. Remember, this water will be over 350 degrees and will cause severe burns instantly! Not to mention the injury caused by shrapnel. In the event of some kind of material failure you will not only have hot, live steam spraying all over the place, but could also spray burning oil/wood/coal whatever for quite some distance.

If your plumbing develops even a pin hole the escaping steam has enough energy to cut through skin in an instant. If the steam is superheated you won't be able to see it so as to avoid it. The steam won't condense into a cloud until some distance from the hole. Believe it or not, steam is also quite abrasive. It will wear channels in your plumbing, weakening it to the point it will have a catastrophic failure.

* PLEASE, FOR YOUR SAFETY, RECONSIDER THIS VENTURE!! STEAM AT ANY PRESSURE IS NOT A TOY![b/]

Something to consider: Those boilers of old, in steamship and mine accidents, were "only" running 75-100 pounds of pressure! Catastrophic failure was often below 200 PSI. It wasn't until the very late 1800's that they got over 200 PSI and that was considered high pressure.

On the ship I sailed boiler pressure was 450 PSI. The only equipment that used that working pressure was the main and auxiliary turbines. All other steam engines used less than 75 PSI, and the eductors used 20-25 PSI.

The pressures you are considering are much too high for a hobbyist to be working with.

Ranger, please understand I'm not trying to be an old fuss-bucket and keep you from having fun. But I feel I have to warn you that this is entirely too dangerous and why.

By all means, build a smaller boiler with much lower pressure. 15 PSI is a good pressure to get some experience with. Build a small engine, run it on air, make it do some work. Then run it on steam doing the same, or more, work. Learn the difference between saturated and superheated steam.

Ok, now I'm off the soapbox.

Good luck, and keep us up to date on what you are doing.


*


----------



## rangerssteamtoys (Jun 8, 2008)

I KNOW THIS IS DANGEROUS

Steam hobby alone is dangerous, I have felt the results before. A monotube boiler is the safest boiler I could find. If the tubing fails, steam and water stays inside the outer shell and doesnt effect me. If it fails in the plumbing going to the engine, the pipes will be insulted and NO WHERE NEAR ME. I will hear the leak and turn on a valve that puts water directly on the fire, putting the fire out. I have about 80% of this figured out. enigne, copper tubing, fire, pulmbing. The only one I havent figured out yet is a water pump, thats why i have a question and the Q and A section.

If you think about a fire tube boiler, well it could send shrapnel no matter what i try to hold it with. 
Look here   http://www.mikebrownsolutions.com/stmpwr.htm

ANY WAYS
I lit a fire underneath the boiler to clean out the insides of the shell. This still doesnt have coper tubing in it yet, just cleaning the boiler, to get any rust or things like that off.


----------



## Cedge (Jun 8, 2008)

Kevin
I think we got to him enough to put him off a pressure vessel type boiler. He's going with a tube type flash boiler which is at least a little less danger of explosions. From the outer shell he's posted above, it appears he's thinking something along the lines of the old Doble automobile boiler. 

If I thought he was working on this,unsupervised, I'd be for tracking his dad down for a brief but serious discussion. I strongly suspect Dad has been watching over the project. If he hasn't been, then Ranger needs to drag him into it at least enough to insure he isn't going to get hurt or blow up the garages. 

I've watched Ranger for a quite while now. He's not afraid to ask questions and it seems he listens when it's important. His "childhood" is something to envy. He's had the freedom to explore his ideas, the leeway to make a few mistakes and parental support for his efforts that I'd have killed for at his age. He's probably as close to living a Huck Finn experience as any kid I've encountered in years.

If he ever gets his hands on proper tools he'll be really entertaining to watch....LOL He's just about learned all the hard ways to get things done and he's still just 14.

Hang in there Ranger, but proceed with due caution and ask for advice when there is even the slightest doubt about safety or proper methods. 

Steve


----------



## rangerssteamtoys (Jun 8, 2008)

Cedge  said:
			
		

> it appears he's thinking something along the lines of the old Doble automobile boiler.
> 
> If I thought he was working on this,unsupervised, I'd be for tracking his dad down for a brief but serious discussion. I strongly suspect Dad has been watching over the project. If he hasn't been, then Ranger needs to drag him into it at least enough to insure he isn't going to get hurt or blow up the garages.
> 
> ...



I am thinking of a doble steam boiler, look here http://www.jaylenosgarage.com/video/video_player.shtml?vid=213453
And yes my dad watch over me closely, infact without him, I would not have copper tubing or the outer shell. I have been asking for advice, but only one person has answered my question under the Q and A section. 

I cant figure out a water pump to use, or why steam doesnt siphon water through the tubes. If steam is leaving a tube shouldn't it be drawing water in? I know that water wont siphon into the tubes but my dad doesnt, he needs PROOF that it wont.


----------



## ksouers (Jun 8, 2008)

Steve,
Thank you for the reassurance. I don't want to discourage his exploration, but I don't want to see him get into any trouble either. And thank you for supervising and encouraging his work. 




			
				rangerssteamtoys  said:
			
		

> I am thinking of a doble steam boiler, look here http://www.jaylenosgarage.com/video/video_player.shtml?vid=213453
> And yes my dad watch over me closely, infact without him, I would not have copper tubing or the outer shell. I have been asking for advice, but only one person has answered my question under the Q and A section.
> 
> I cant figure out a water pump to use, or why steam doesnt siphon water through the tubes. If steam is leaving a tube shouldn't it be drawing water in? I know that water wont siphon into the tubes but my dad doesnt, he needs PROOF that it wont.



Ranger,
Simple physics, high pressure always flows to low pressure. Water won't syphon back in because the steam is always expanding until it runs out of water to turn into steam. That's also why it is so dangerous. The pressure of the steam will always push the water back until and unless the pressure of the water is greater than the pressure of the steam. That is why you need a check valve on the inlet side.

Now, consider if you had a container of water higher than the boiler. The water has weight, it pushes down. If you ran a tube from the container to the boiler inlet, that tube will have a certain amount of pressure at the inlet. It's called head pressure. Head is the distance the water has to fall. The more water above it and the farther is has to fall the more pressure it has. Head pressure is the weight of the water in a water column, the tube, often referred to as so many feet of head. The volume of water in the container is not important, it's the height that is important. There is a formula for calculating the head in a water column that escapes me at the moment, you could probably google it. This will tell you how high to put the container to reach the pressure that you need to overcome the steam pressure and feed water to your boiler. If you find that the height required is too much, say 30 feet or something, look for a pump that has 30 feet of head (yes, they are rated that way). I would suggest using a centrifugal pump. You would want to regulate when and how much water is fed to the boiler, a positive displacement pump will be damaged or cause damage if the flow is stopped. A centrifugal pump will just spin in the water, it won't like it much, but it will survive.

One consideration is making a piston steam engine and powering a piston pump for your feed water. That's what we used on the ship as a backup. The main feed pump was a steam turbine powering a centrifugal pump. If you use a positive displacement pump such as a piston or diaphram pump, put a return line on the pressure side. It would also be a good idea to have a return line on a centrifugal pump. Put a valve on the return line to regulate the pressure.

Hope this answers your question. If not, keep asking. We'll get there eventually.

Good luck.


----------



## rangerssteamtoys (Jun 8, 2008)

Thank you Kevin, Finally an answer that can help. A gravity fed system to fill the boiler, that could work. This is the kind of help I need. 

This is my idea, a mechanical feed pump that is also hand operated. A simple stephensons link to switch from mechanical or hand pump. My idea is a small pump like this one http://www.tinypower.com/store2.php?crn=57&rn=276&action=show_detail
I get an eccentric to make it work off the engine and in between the eccentric is the stephensons link. For the first few minutes I have to hand pump after I get about 50 psi I can start the engine. 50 psi is the optimal starting pressure for the engine I have. I switch to mechanical and let the engine fill the boiler, a valve will control the water input. 

Now another question, about the copper tubing itself. How much pressure will 100' of 5/8" OD 1/2" ID copper water tubing hold?
What is copper water tubing? Is it any good?


----------



## tel (Jun 8, 2008)

You should be OK with the copper pipe at 120 - 150 psi, which is, after all, a pretty moderate pressure for a mono-tube. The trick is going to be limiting the pressure to that. You are going to need some sort of relief valve (safety valve) toward the delivery end of the system for WHEN (not if) the pressure tries to go above that. I would suggest some sort of manifold at the delivery end, incorporating at least two safety valves and two or three delivery valves.

You are on the right track with the feed pump, but again, you should consider a second pump in the system in case of failure. All my (fire tube) boilers have both and engine driven and a hand pump. One consideration would be simply to keep your hand pump seperate from the engine driven one. Start on the hand pump and then switch over.


----------



## rangerssteamtoys (Jun 8, 2008)

I will have an air compressor saftey valve set at about 160 psi. I want 150 psi max, so i will have the saftey set higher than that. Any ideas of the volume of steam from this boiler? I need alot of volume the engine I have is a air eater so I assume it will be a steam eater as well.


----------



## mklotz (Jun 8, 2008)

The formula is P=rho*h/144, where:

P = pressure (psi)
rho = density of water (62.38 lb/ft^3)
h = head height (ft)
144 = conversion from ft^2 to in^2

A one foot head of water exerts a pressure of 0.433 psi. A 2.309 feet head of water exerts a pressure of one psi.


----------



## rangerssteamtoys (Jun 8, 2008)

mklotz  said:
			
		

> The formula is P=rho*h/144, where:
> 
> P = pressure (psi)
> rho = density of water (62.38 lb/ft^3)
> ...



So 2.309X160=369.44 feet to over come 160 psi. WOW thats a pretty tall steam buggy. Can it fit in the garage?


----------



## Bernd (Jun 8, 2008)

Ranger,

Quite a few have given you go answers to getting water into a boiler. On a model steam locomotive, and the prototype steam engines, there are three ways of accomplishing getting water into the boiler. 1. - hand pump, 2. - axle pump, 3. - steam injector. The first two are easy to understand and are used exclusively on models. The third is used on the real thing. The third is a bit harder to explain or understand. I suggest that if you are interested in steam power you study how steam locomotives and model steam locomotives are built and work. 

Here's a web site that you might find interesting, http://www.nelsonslocomotive.com/Shay/shay.htm. Scroll down to the "plumbing" section and check out his hand pump and axle pump. Also some where in there you'll probably find how to plumb up the hand pump and axle pump.

Hope this is helpful to you. May I also suggest getting some books on this subject. Not everything can be found on the internet. 

Regards,
Bernd


----------



## chuck foster (Jun 8, 2008)

ranger..........i have a very limited knowledge about steam boilers and engines. 
one thing you mentioned is that your engine runs on about 50 psi. i think with the expansive force of steam you might be able to run the engine on a lower pressure.

also do you have drains fitted to the engine cylinder?
if you dont you might have problems with water in the cylinder. after you are done running the engine on steam and it cools down the steam will condense into water and the next time you apply steam or air the water in the cylinder might cause the engine to not turn over or blow the head off.
i think what im referring to is hydraulicking ( guys......am i right??? ??? )

with all that said i think you are doing a great job and i wish you all the luck in the world, you are proving to be one very smart young man and i look forward to more of your postings. 8)

be safe and have fun ;D

chuck


----------



## rangerssteamtoys (Jun 8, 2008)

chuck foster  said:
			
		

> also do you have drains fitted to the engine cylinder?
> if you dont you might have problems with water in the cylinder. after you are done running the engine on steam and it cools down the steam will condense into water and the next time you apply steam or air the water in the cylinder might cause the engine to not turn over or blow the head off.
> i think what im referring to is hydraulicking ( guys......am i right??? ??? )
> 
> chuck



Yes thanks for reminding me about the water building up in the cylinder, I need to figure out how to drain water from the cylinder. Maybe a running it on air after every steam useage would get the water out? I'm using my converted gas engine, so I dont think there will be a way to connect a drain because the engine is vertical and single action. Only way to drain water out is to drilll a hole in the cylinder wall creating a uniflow exhaust.


----------



## rangerssteamtoys (Jun 8, 2008)

Bernd  said:
			
		

> Here's a web site that you might find interesting, http://www.nelsonslocomotive.com/Shay/shay.htm. Scroll down to the "plumbing" section and check out his hand pump and
> 
> Regards,
> Bernd



Thanks for the link, I believe that I can convert a hand pump to mechanical. All I need is an eccentric and a stephensons link, where to get one of those?


----------



## ksouers (Jun 8, 2008)

Ranger,
Marv gave you the formula I was talking about earlier, to calc head. 
Chuck makes a very good point about the expansion of steam. That is what makes steam work. It is also the danger. One gallon of water at 350 degrees will expand into A LOT of steam. You probably won't need as much pressure as you think, there is A LOT of energy pent up in just a little bit of water.

A couple things to consider:
You probably won't need to pump water by hand. No water will be flowing while the boiler is warming up. Have some water in the tube during warm-up with all valves closed except the feed water return, when you start getting some pressure, maybe 20 PSI, crack the main stop valve (that's the valve between the boiler and your engine) and let the engine start running. When the engine starts running, open the stop valve fully, remember to crank it back towards closed about a quarter turn. Also remember it will be hot, wear gloves. You should have water circulating through the return line with the return valve fully open. As you start running out of steam and the engine starts slowing down, start closing down the return valve to increase pressure at the check valve/water inlet, but don't fully close it. Leave some running to keep from damaging the pump and linkage.

You will probably find that your engine runs quite well on a lot less than 150 PSI.

As for a drain on the engine: This is a converted Briggs & Stratton, right? Does it still have the spark plug hole? You could put a drain cock on that.


----------



## rangerssteamtoys (Jun 9, 2008)

I really appreciate your help Kevin. Will the spark plug hole act as a drain? Since its a vertical engine I dont think water will drip out. I may want to go with a single uniflow exhaust hole, it will not be for exhust but simply drain water.

Ok, now I just have about everything covered on the boiler, now for fire. I want to run on a gravity fed oil system, but any other suggestions will help. *No Propane*.


----------



## ksouers (Jun 9, 2008)

Ranger,
You're quite welcome. I'll help any way I can, I'm sure everyone else will too. We would like to see your project be successful. But also very safe.

The spark plug hole can be a drain, but you'll have to put a valve on it so you can close it off.
Are you still using the old Briggs oiling system? A splasher or a pump on the cam?
If you aren't, you could run the engine upside down. If you are, then make a removable crank handle for the driveshaft. After you shutdown the engine, AND DISCONNECT THE STEAM LINES, open the drain and crank it over by hand a few times. This will displace any steam left in the cylinder. Leave the valve open so any moisture can evaporate.

Firebox:
I can think of a few fuels you might want to use. Each has advantages and disadvantages, naturally. I'll spell them out as I see them, you get to decide.

Wood: pro:cheap, abundant con:may be hard to start. Hard to control. Burns irregularly.
Charcoal: pro:abundant, reasonably priced, easy to light con:hard to control. Burns irregularly.
Alcohol: pro:abundant, easy to light, easy to control con:very expensive, half the energy of gasoline.
Gasoline: pro: significant energy, easy to light, easy to control con: highly flammable, very dangerous, expensive.
Diesel fuel: pro: more energy than gasoline, easy to light, easy to control con:expensive, dangerous.

First thing, toss out gasoline. That's a non-starter. Way too dangerous.

Alcohol seems like a good choice, but it is very expensive. You will need a significant amount and it is more expensive than gasoline.

Wood and charcoal are good choices. They burn slow, but hot. Lots of energy there. And the price isn't bad. But the fire can be difficult to control, it flares up and burns down to just coals. Still, a good choice. You will need a quick way to extinguish the fire.

Diesel fuel could also be a good choice with a proper burner and flow control. It is expensive though, more so than gasoline. It burns fairly slow for a liquid, but hot. Lots of energy, significantly more than gas. Kerosene could be substituted.

Do some reading, learn how a fire works. What three things does a fire need to sustain itself?
How does fuel actually burn?



Before you start building you need to think about a couple things. How are you going to operate your boiler? How are you going to start it? What steps do you take, in what sequence?
What is the maximum length of time you will operate the boiler?
How will you shut it down? What are the steps? How are you going to test your boiler?
How will you identify a pending emergency? What will you do to prevent it becoming an emergency?
What will you do in the event of an emergency? What kind of emergencies are possible? Not just best-case scenarios, what is the worst that can happen?
Believe it or not, most accidents can be avoided through very simple measures. It's just that too often people don't think about them.

If you are going to operate your boiler in a safe and professional manner, you will need to know these things.

Above all, ask questions.


----------



## tel (Jun 9, 2008)

rangerssteamtoys  said:
			
		

> I really appreciate your help Kevin. Will the spark plug hole act as a drain? Since its a vertical engine I dont think water will drip out. I may want to go with a single uniflow exhaust hole, it will not be for exhust but simply drain water.
> 
> Ok, now I just have about everything covered on the boiler, now for fire. I want to run on a gravity fed oil system, but any other suggestions will help. *No Propane*.



The idea is not for the condensate to drip out, but to be expelled by the rising piston/expanding steam - hence the need for a cock. When starting up you open the cock until the engine heats up, blowing the condensate out, if your steam is particularly wet you may also have to crack the cock periodicaly during the run.

Here's one of my engines, a single acting double, fitted with automatic drain cocks - note that they are as high up on the cylinders as I could get them.


----------



## rangerssteamtoys (Jun 9, 2008)

ksouers  said:
			
		

> Before you start building you need to think about a couple things. How are you going to operate your boiler? How are you going to start it? What steps do you take, in what sequence?
> What is the maximum length of time you will operate the boiler?
> How will you shut it down? What are the steps? How are you going to test your boiler?
> How will you identify a pending emergency? What will you do to prevent it becoming an emergency?
> ...



Believe me, I have sit in a chair having so much fun going over the process of running the engine ;D Thats where being a kid helps, you can pretend without looking like an idiot :bow: 
I can answer most of the questions, except the what to do in the event of an emergency, I cant plan ahead like that. If I dont plan ahead, I usually do pretty good in an emergency :-\ 
As for the burner I'm probably going with a forced air oil burner, the firebox will need a bit of refractory to withstand the heat. Look at this http://www.backyardmetalcasting.com/oilburners08.html Pages 8-9 is what I'm thinking. I cant get it to go vertical so like I said refractory will be needed or some insulation to prevent melting the firebox.

Now back on the water pump, I well my dad gave me the idea of using a new grease gun. It can give good pressure, pump quite a bit of water, has built in check valves (I think, and hope) and is easy to get, also CHEAP

As for the drain cocks, thats a good idea. Use steam to blow out any water at first. I will have to make a mark on the pulley to do that so I can get it between TDC and BDC on the intake stroke. Open the drain and warm up the cylinder that way, since the gas engine is designed to get rid of heat; I will have to insulate the cylinder. Work on that tomorrow. 
Cost of this project so far, $0.00 I want to get costs to a minimum.


----------



## ksouers (Jun 9, 2008)

rangerssteamtoys  said:
			
		

> I can answer most of the questions, except the what to do in the event of an emergency, I cant plan ahead like that. If I dont plan ahead, I usually do pretty good in an emergency :-\



First:
You can.
And you must.

If you don't plan ahead, if you just plunge in head first without preparation you WILL have a disaster!

Read what I wrote again. Look at it from a different point of view. Those things are to PREVENT an emergency situation. You need to know those things so that you can catch problems BEFORE they get out of hand.

Possible scenario:
The tube ruptured and sprayed hot, burning oil all over the yard. No one is hurt but the grass is on fire and the wind is blowing the fire towards the garage. 

You didn't plan ahead:
Where's the fire extinguisher? In the garage? In the kitchen? Where is the water hose? The front yard? While you're running around, the garage catches fire.

You DID plan ahead:
The water hose and fire extinguisher are right there with you. You grab the hose and start dousing the leading edge of the fire. Disaster averted by simple, easy preparation and forethought. Yeah, the grass got scorched. It'll grow back. But the garage, Corvette and Chevy are safe. So is Ranger.


----------



## rangerssteamtoys (Jun 9, 2008)

Well for me, all those things are second nature. I did another firing of the boiler today, again just the outer shell. Water hose was about 3 feet away from me if anything went wrong. Like say the prototype oil burner I was testing, blew up sending hot oil lighting the grass on fire. The water hose is right there, if I were to use a fire extenguisher, my dad would just get mad at me.


----------



## ksouers (Jun 9, 2008)

rangerssteamtoys  said:
			
		

> Well for me, all those things are second nature. I did another firing of the boiler today, again just the outer shell. Water hose was about 3 feet away from me if anything went wrong. Like say the prototype oil burner I was testing, blew up sending hot oil lighting the grass on fire. The water hose is right there, if I were to use a fire extenguisher, my dad would just get mad at me.



That was good. That was a much better answer than your other one.

If your life or the house was in danger I seriously doubt he would get mad at you for using the extinguisher. Now, for starting the fire in the first place is another story...


----------



## Circlip (Jun 10, 2008)

Not wishing to fan the flames but NEVER use water on an oil fire, play safely,
 Regards Ian.


----------



## tel (Jun 10, 2008)

As for the drain cocks, thats a good idea. Use steam to blow out any water at first. I will have to make a mark on the pulley to do that so I can get it between TDC and BDC on the intake stroke. Open the drain and warm up the cylinder that way, since the gas engine is designed to get rid of heat; I will have to insulate the cylinder. Work on that tomorrow. 
Cost of this project so far, $0.00 I want to get costs to a minimum.

You're missing the point - the engine should run with the cock open and the action of the piston will pump it out. Have a look at video of a locomotive starting off - those white puffs coming from the cylinders are the result of the cocks being open


----------



## rangerssteamtoys (Jun 10, 2008)

tel  said:
			
		

> You're missing the point - the engine should run with the cock open and the action of the piston will pump it out. Have a look at video of a locomotive starting off - those white puffs coming from the cylinders are the result of the cocks being open



I dont think my engine will run with the drain cock open. I will have to test that today on air, put in a bolt that has a hole in it.

Circlip, the water was just to put out any fire, if it were oil, I have ashes left from a recent fire to throw on it. I tried it and it works well.

You guys have sure got me thinking about this boiler, I'm still going through with it but ALOT more cautiously. Back on the boiler, I have 1 coil of copper that is 60 feet long the other is about 50 feet long. I want to connect them together, how should I do this, with silver solder, flaring tool. What?


----------



## rangerssteamtoys (Jun 12, 2008)

Well I have a system to coil the tubing, its essentially a 5 1/2" thick wall steel pipe welded down to a metal grate and strapped to a pallet, so I can move it with the forklift. We are going to do some testing with some short pieces of tubing and try to bend it. The first test ended up with a small coil but the copper was bent into an oval shape. Is this OK?? We are goign to try another piece filled with sand and hope that will keep the oval shape to a minimum. I plan to have 2 coils, I wrap the tubing into a coil about 20" long with about a 6 1/2" diameter coil and just wrap the next one right over top of the other. I need to join the tubing and have a 45 degree bend that will work, I will braze the 2 pieces together.


----------



## Cedge (Jun 12, 2008)

Ranger
I'd use silver solder. Brass is not the ideal choice due to both chemical properties which allow dezincing and less tolerance for expansion and contraction.

Steve


----------



## rangerssteamtoys (Jun 12, 2008)

Sandy suggested something called Silver Braizing. Regular silver solder that I have will melt very easy, its the cheap-o plumbers silver solder.


----------



## Cedge (Jun 12, 2008)

Ranger
Terminology is the bane of all engineering. The Silver Brazing is the real "silver soldering". what you have is silver "bearing" solder with anywhere from 2 - 5% silver content. It's fine for most no pressure or low stress joints. The "brazing silver" version can have from 40 - 60%. Much stronger stuff. You're on the right track.... "Brazing" just didn't convey it.

Steve


----------



## SandyC (Jun 12, 2008)

;D ;D

Hi Guys,

Steve.... yes it is the high silver content type I was suggesting, as you say terminology can be a problem.

Ranger... You must keep your tube as near to round as possible when you do the coils, otherwise you will run the risk of tube collapse under high heat and pressure.

Also, 5 1/2" - 6 1/2" ID for the coils is quite a tight radius for this size of copper tube.
If it is flattening to much then it may be advisable to fully anneal the whole roll first.
Heat it up to a dull red all over and then let it cool down. This will soften it and make it easier to form the bends with.... go easy though since it will be very soft in this state.

As you bend it into a spiral form it will work harden a bit.

Make the individual loops of the spirals with a gap/space between them of at least 1 tube dia.

The second row should also have the gap/space between the loops, but of course, with a larger inside dia.... again keep this to approx 1 tube dia difference all round (I.E. make the ID of the 2nd coil 2 tube dia's bigger than the first coil OD).

You must have these spaces to allow the hot gasses to get to as much of the surface of the coils as possible.

A half round wooden former, with say a 6" outside radius, having an angled semi-circular groove cut into it's outside (curved) surface (the width of the coil tube outside dia and half the depth of the tube dia) will make it a bit easier to form the coils and keep the tube round. It will also help if you have a second straight piece of wood, with the other half circle shape cut in it, to push the copper tube round the former.

You will need to get your Dad to help you with the SILVER soldering (silver brazing) since it will require the use of a reasonable size blow torch. (Silver solder (Silver Braze) with 40% silver content requires a temp of around 630deg C to melt and flow into the joints)

Making spiral tube sets is not the easiest thing to do, so take your time and work slowly.

Hope this makes things a bit more clear.

Best regards.

SandyC&#160;  ;D


----------



## rangerssteamtoys (Jun 12, 2008)

The 5 1/2" pipe didnt work for a coiler, as you said. I tried it and it made the pipe in a nice oval shape. I'm going to try something like 6 1/2" diameter pipe.


----------



## ksouers (Jun 12, 2008)

Ranger,
You may have to buy a conduit bender sized in the same diameter of you copper. The trick is trying to keep the "top" (outside radius) from flattening and thus kinking the sides. It's hard to describe, I hope you can visualize what I'm talking about. You can probably see it in your sample bending.

If you can't buy one, you can make one out of wood. I hope I can describe this sufficiently.

You will need three triangular pieces of wood. One piece is as thick as the diameter of your copper tube. You will have to cut a radius in one side of it, the same as the inside radius of your proposed coil. The arc of this radius should be about 1/4 of your coil circumference, maybe a little less.

The other two pieces of wood can be 1/2 inch plywood. You will want to cut them the same except the radius will be the outside diameter of your coil. Basically, the inside diameter of your coil plus the size of your tubing. Maybe just a little bit more, say 1/8-1/4 inch.

Fasten the two pieces of plywood to either side of your other wood wedge making a sandwich. You should end up with a pie-shaped wedge with a groove around the outside circumference of the arc. Now you will need a piece of heavy gage metal or stout plywood about 1 inch wide. Fasten that to one end of the arc.

Get a broom handle, paint roller extention, piece of iron pipe. Something stout to use as a lever. Drill a hole at the apex of the wedge radially. You now have a tubing bender.

Lock the free end of your tubing under the "bridge" and tail the rest of your tubing out along the groove. You can set this down on the floor with the handle pointing up. You should now have the tubing in the groove and pinched between the bender and the floor. Rock the handle, rolling the head of your bender on the floor. As the tubing is bent, rock forward and feed some more tubing then rock it back again. 

Does this make sense? If not, I'll try to draw some diagrams for you.


----------



## rangerssteamtoys (Jun 12, 2008)

ksouers  said:
			
		

> Does this make sense? If not, I'll try to draw some diagrams for you.



I can't really imagine the bender your describing. I have an idea though, get a hole saw and cut about 20 wheels, screw the wheels down to a piece of plywood in a circular pattern to make the ID and OD of the coil. Have one opening where you can feed in copper. As it goes in the wheels will help it form a coil, to get the copper to raise up from the jig add some wedges near the end of the circular pattern. Just keep feeding in tubing and it should coil and raise at the same time. 

I'm also thinking about just wrapping it around a bigger pipe, we tried a telephone pole that is used for a support beam in a barn. It worked great, but how to get the coil off? :big: :big: We have some extra poles to use but that requires alot of digging and cutting. I will do some more tests, see what works. 

I would like to see some sort of diagram, please.


----------



## ksouers (Jun 12, 2008)

You have to keep the sides of the tubing from spreading out. When bending, what you really are doing is stretching the outside bend of the tubing.

Take ride down to Home Despot or Lowe's and take a look at a conduit bender in the electrical department. You'll get a better idea of what I was describing. I'll try to have a drawing for you Friday night.

Here's a link to a bender at Lowe's:
http://www.lowes.com/lowes/lkn?action=productDetail&productId=76063-1781-931B&lpage=none


----------



## rangerssteamtoys (Jun 13, 2008)

ksouers  said:
			
		

> You have to keep the sides of the tubing from spreading out. When bending, what you really are doing is stretching the outside bend of the tubing.
> 
> Take ride down to Home Despot or Lowe's and take a look at a conduit bender in the electrical department. You'll get a better idea of what I was describing. I'll try to have a drawing for you Friday night.
> 
> ...



Oh we have plenty of conduent benders (this is a construction company), we tried that and it didnt work either. We know some people who have copper tubing benders, we are trying to get them to bring them today.


----------



## kvom (Jun 13, 2008)

I think you need to have the groove in the bender exactly the same as the OD of the tube. I've heard that filling a tube with sand can help prevent it from kinking when bent.


----------



## rangerssteamtoys (Jun 13, 2008)

kvom  said:
			
		

> I think you need to have the groove in the bender exactly the same as the OD of the tube. I've heard that filling a tube with sand can help prevent it from kinking when bent.



Thats a copper tube bender. We have some small ones 3/8" diameter but thats not 5/8"  The copper tube bender is a very well designed bender, so if we can get a big one we might have something to work with.


----------



## rangerssteamtoys (Jun 13, 2008)

SAND is the key. Kvom, you were a supporter in this but we had already tried it. I went out and tried a different process and it worked perfectly. A nice 6 1/4" diameter OD coil, I used about 6 feet of sand filled copper. Now I'm thinking about making a turn table for the pipe. I can attach a crank to the pipe and spin the pipe while someone holds the sand filled copper. Now how to fill up 60' of copper tubing?


----------



## georgeseal (Jun 13, 2008)

Maybe a 60' step ladder :big: :big: :big: :big: :big:


----------



## raym 11 (Jun 13, 2008)

Don't forget the most important things. 

Hydrostatic testing of completed boiler.

Calculation of *Pressure Relief Valve  * sizing and pressure setting.

Ray M


----------



## rangerssteamtoys (Jul 5, 2008)

ElGringo  said:
			
		

> Don't forget the most important things.
> 
> Hydrostatic testing of completed boiler.
> 
> ...



How do I calculate a pressure relief valve. I was going to use one from an air compressor. 

As for the boiler, I have not made much progress. The valve tappet on my 2hp Briggs broke so its no good till I get another. But I have converted the 5hp Briggs, it gives quite a bit of power.

I figured the boiler needs to only go up about 70-80 psi max. Not the 150 I had hoped for, but its safer this way. My bigger and more powerful engine only need about 55 psi MAX that gives about 700-800 RPM. With steam I hope I can get more speed and more power.

Now for the question, can I make a monotube boiler only go up to 80psi max? To do this I would need a very small fire, right? Its getting to be the time to make the boiler that I have been putting off, getting technical; not something that I'm really good at.


----------



## rangerssteamtoys (Jul 11, 2008)

Progress has been made. Today I coiled and soldered the tubing. Its about 50' of 1/2" in a 8" diameter, I will try to get some pictures. 

Here is a problem that has occured though, the coils need to have an entry and exit and to do that I need to couple the copper tubing to some copper pipe. I have the couplers and know how but its just the saftey, one couple has to be next to the fire. I have some really good silver solder but am still worried, do you think that this will be OK? 












Here is a coupler to connect the length of tubing together. The longer lenghts are closer to the fire, shorter ones are farther away





I added this piece of tubing on so the steam water in and steam out are next to each other. It will make it easier for me to plumb the boiler this way. There is less pipe needed and the tube acts as a preheater.

It basically goes right down the middle





I'm proud of what I have done, in all there is 53 feet of coil to be heated. I have some extra but it was getting close to not fitting in the outer shell. 

Can anyone give some advice on how to hold the coils in the boiler???? I'm going to have a problem with that ???


----------



## Florian (Jul 11, 2008)

Hi ranger(steamtoys) 

1. I would put another tube into the boiler which has the inner Diameter of your coil minus 2 inches. This would make the fire go over your coil and i think it would make your boiler more efficient. -> If you don't have any idea what i mean, ill make a sketch. Of course, on the bottom you would need to fit a cone to the tube. 
To fix your tube, you then could ad bolts from the outer tube to the inner one (if you are going to make such a tube) and then just have your coil supported by the bolts. And i would fix the coil where it enters the outer tube and where it leaves the outer tube.

2. Security-valves: I don't know if the security valve of a compressor is suitable for steam. Maybe the sealing is not for these temperatures. (If you want to use one.. check this first!)

Maybe you should couple the copper pipe with the tubing on the outside of your outer tube. But actually it should not get damaged if you always have some cold water being pumped into your tube-coil. 
For Firing it, i think it would be best, if you make a circular tube burner using propane. (so you can adjust the fire to the steam consumption.

Florian


----------



## raggle (Sep 16, 2008)

I'm late in this thread having joined you all only yesterday.

Seems there has been no activity here since July - did I miss something? Was there a loud bang or hiss out west?

I've been interested in flash steam boilers since I read a book borrowed from the library on Doble Steam Cars about 30+ years ago. Shortly after that, when I was making a good living chemically descaling boilers and other heat exchangers, I was called to a Stone's Generator for descaling. I was delighted to find that I could leave my pumps unused on the truck. I needed to ask the proprietor of the knitwear factory for a look at the manual.

There were two diaphragm pumps in the system, operated by cams from the motor and controlled by electro solenoids which held the diaphragms still when needed. Neither got hot, the valves being at one end of a long-ish pipe and the diaphragm at the other, well away from the circulating steam coil. One pump fed the boiler, the other kept it circulating.

The basic principle is that the water is continuously circulated through the single coil which may be several hundred feet long, thus no steam pockets can develop. These would lead to "dry" areas which would be quickly burned by the fire, rather the fluid is water containing bubbles of steam. Near the top of the coils the fluid escapes into a centrifugal separator which also contains high and low water level sensors. Steam output from the top of this chamber is passed through a small number of coils in the flue in order to dry it and maybe give a little superheat.

In the foregoing I believe it is identical to the Doble's boiler, possibly even depending on Doble's patents.

The Doble car was fired by kerosene through a carburettor and could get 30 miles per US gallon. This was due in no small part to its excellent condensing system. 65% of the used steam was recycled, so its water tank could be quite small and there was no telltale cloud following it like those of the Whites and Stanleys.

The "compact" car that failed to get into production (concocted financial irregularities scuppered it so I believe) was to have a simple uniflow engine, unlike the DA one of the large cars, much as you have mentioned with your B&S engine. A good vacuum in the exhaust here would be a great advantage.

Doble Henschel ran steam locomotives in Germany for some years and the boilers found their way into diesel powered passenger trains for heating.

http://webserve.govst.edu/users/gaskrau/vapor.html

They seem to be more correctly referred to as vapour generators, but I remember being told they were used on board ship to power small auxiliary engines for pumping duties, etc.

To sum up, a flash plant should be an automatic unit with safety built in. Circulation of the water is essential, not just desirable. Overpressure, low (or high) water and over temperature of combustion outlet must ALL shut down the system.

I'm not sure of the use of copper pipe as a material, but probably fine for the circulated fluid. If you ever go the way of superheat those last couple of turns should be steel. After all, they won't suffer much scale.

I wish you well with the project. You have exactly the right attitude. Maybe it's a little on the large side for an experimental rig. 

Ray


----------



## taterfarmer (Dec 19, 2020)

hay, this about  how far along  i am on my monotube  boiler


----------



## Richard Hed (Dec 20, 2020)

taterfarmer said:


> hay, this about  how far along  i am on my monotube  boiler


As for myself, I thimk a single tube is dangerous because of the steam bubbles building up and moving upward thru the tube.  I thimk that several tubes coming from a base and moving upward to a manifold is less dangerous.  If built right, it should have circulation built in.


----------



## 57mm_M18 (Dec 20, 2020)

raggle said:


> I'm late in this thread having joined you all only yesterday.
> 
> Seems there has been no activity here since July - did I miss something? Was there a loud bang or hiss out west?
> 
> ...


----------



## 57mm_M18 (Dec 20, 2020)

I don't know if this link will work properly.  I sometimes have issues with digital systems.  Anyway, here is a link to some drawings of the single tube boiler being discussed here.



			Kimmel Steam Power


----------



## Steamchick (Dec 21, 2020)

rangerssteamtoys said:


> How do I calculate a pressure relief valve. I was going to use one from an air compressor.
> 
> As for the boiler, I have not made much progress. The valve tappet on my 2hp Briggs broke so its no good till I get another. But I have converted the 5hp Briggs, it gives quite a bit of power.
> 
> ...


Hi Ranger.. I have just picked-up on this one, as I have been busy with life, odd jobs and other threads.... But I have just spotted your "boiler" ideas and discussion. Please forgive me if I seem to be "teaching Grandma how to boil the kettle" - but there are a few MUSTS - as suggested by ElGringo, Richard, Ray and others who probably know more than I do.
But here are some MUSTS - taken from the ASME Regulation: Incidentally, before anyone gets a bit "gung-ho" about my quoting a Regulation and says it doesn't apply to them, please put your sensible head on and ask yourself if you want a boiler to blow up and kill you or your loved ones... Actually, Regulations are Law in the countries to which they apply, but I don't care about anyone breaking their laws, as long as they don't break hearts.... Steam is flippin dangerous! - Hence Boilers and equipment need PROPER control.
The simple rules  (I won't just quote Regulations, but here's common sense as well...).

A Boiler shall be properly designed: - I,E, Calculations for strength, sizes of materials, heating and safety valve sizes, etc. And if you don't know how to do it, get a real professional design and use that. (NOT just something someone gave you of a boiler that "does the job", but one with a certified engineer's name to it. As you have made a coil, I suggest you get the calculations done before doing anything else - so you do not do any wasted work but have a good boiler.
The Regs talk about the Maximum pressure for a silver soldered copper boiler as being based on material taking a max. stress of 3000psi. - which is based on the Maximum allowable stress at 400deg.F. (205 deg.C). Beyond that temperature, the copper and silver solder are simply not good enough. - So you need to calculate what pressure you can permit for your various tube diameters and wall thicknesses. Take a sample of the bent tube as per your coil and cut it carefully into some pieces, then check the minimum thickness of the copper that has been stretched (and thinned) by the bending process, Including any proprietary bends or other components. You must use the THINNEST of the measured wall thicknesses in any calculations - and even then be generous to be safe. You cannot know the thinnest point of a coil that is in effect 50ft long, so make allowances for the process having some areas thinner than others. Also, I am assuming it is seamless tube? - You can't use seamed tube in boilers according to my understanding of UK Regs. Common "plumbing" pipe is OK for water up to 100deg.C or 212 deg F. for the pressure it says on the label. BUT at the temperature for 80psi you want to HALVE that pressure to avoid over-stressing the copper tube - according to the Regulations. So, unless the tube is factory approved for 160psi or over for domestic water supply, then scrap it and get heavier gauge tube that is good for well over 200psi "domestic temperature" water...  Then think about temperature of your superheater, and maybe use better material than copper for that? 
Incidentally, Lead or tin soldered joints will fail in a boiler to steam above about 15psi NWP. - And you want 80psi NMP!! So don't use ANY soft solder on your boiler.
Safety valves: The safety valve needs to be capable of preventing over-pressure when the fire is at its maximum. So you need a good understanding of what fuel, how much fuel and air can be supplied, and the total heating area of the boiler so you can calculate how much steam - at *84psi* the safety valve needs to be capable of venting. Don't just fit one off your compressor. Steam is NOT air and although "at lift" the safety may do the same job, it is doing a different job to limit the pressure of the HOT steam compared to Cold compressed air. Gas flow through the valve, and all that. I have proprietary safety valves for air and they perform differently with steam - and vice-versa with the steam safety valves. So now I make my own STEAM designed safety valves - which work nicely - without over-pressure during the safety certification test, and without washing the garage roof when they blow!
There is a lot more... but I think you should digest this lot and others' comments first before you make anything else?
Keep on, as it is an interesting project. - Maybe it is mentioned earlier - and I haven't read everything yet (life is too short!) - but what dimensions are the bore and stroke and max. revs for running your engine? - That is the STARTING point to design a boiler... too many people start off guessing the size of boiler and end up too small - more wasted work. I buy those boilers and re-fit them. - People think my boilers are a bit large, but they won't be short of steam - and they perform as the calculations predict.
Ask when you need more information. 
Cheers!
K2


----------



## Steamchick (Dec 21, 2020)

Hi again Ranger, I forgot to mention that the Hydraulic test pressure for your boiler with NWP = 80psi shall be at least 204psi according to ASME regulations. 
Min. Test value = NWP x 1.3 x Stress value for cold/stress value for temperature at NWP.
I.E. 80 x 1.3 x 6700/3418 = 204psi: So use 205psi min test value.
IF you are sure your tubing is good enough material (by reference to the maker's data on application and Normal working Pressure - then halved by calculation to see if it is OK for >80psi... and after checking any thinning from the bending...): 
I suggest you do a 20 to 30psi air-leak test on your tube before progressing further, as you have some joints in it.  Hold air for >15mins without pressure dropping, and check all joints with soapy water for bubbles all through the 15 mins. ANY bubble forming in the 15 mins must be fixed. Then repeat at 50psi, then 70 psi, then in 10 psi intervals up to 120psi. If you can do it in a bath - with the tube full of air but immersed under water - then bubbles may be easier to spot than soap bubbles. But you need to be able to examine all the way around all the joints and watch for 15 mins as a small leak may take that long to show a single bubble. Trust me - I did it as a job.
When definitely leak free with air, completely fill the boiler with water, all openings sealed and pump water to >205psi and hold for 15 mins. Only then should you bother making anything else...
But if the tubing isn't good enough on calculation, beforehand, don't bother even testing it. Use it for something else and not the planned steam boiler.
Did I suggest it is an "interesting" job?
K2


----------



## Steamchick (Dec 21, 2020)

Hi Guys. I just spotted the dates on the postings while reading this one from start.... Seems I am 12 years late joining the party!
Ranger - Are you still around? - Hope you made a boiler and it worked safely. You had a couple of good guys as mentors while you were making that rig - including your Dad - from what I read.
As a few of us have just been joining this old thread, perhaps you can bring us up to date with your life, the universe, or anything?

Taterfarmer - is that Montana? If so, the ASME code is applicable to you. It seems you are doing something similar - making a tube boiler - so please ask if you want some help (from the UK!). I'll try my best.

Cheers!
K2


----------



## taterfarmer (Dec 26, 2020)

copper  tubing  wasn't  holding  up  to  temperature  or pressure  i was reaching  for. i now have 20ga. stainless  steel  1/2" tubing .

on the  construction  of  a vertical   flash boiler  :: anyone  kno  whether  its better  to  inject  water from  the  top or bottom  of  the  coil?
..
in my  research  it seems different  people  have  different  preferences...


----------



## Richard Hed (Dec 26, 2020)

taterfarmer said:


> copper  tubing  wasn't  holding  up  to  temperature  or pressure  i was reaching  for. i now have 20ga. stainless  steel  1/2" tubing .
> 
> on the  construction  of  a vertical   flash boiler  :: anyone  kno  whether  its better  to  inject  water from  the  top or bottom  of  the  coil?
> ..
> in my  research  it seems different  people  have  different  preferences...


I would say if the water is hot when injected, that it wouldn't matter where you injected it, however, if the water is cold, I would thimk it would be best to inject it at the bottom


----------



## Asm109 (Dec 26, 2020)

Given that the OP has not been on the site since 2010, I don't think any updates will be forthcoming.


----------



## Steamchick (Dec 26, 2020)

Maybe the adjudicator can move all 2020 posts from n to Taterfarmer to his other thread on this boiler?
K2


----------



## Steamchick (Dec 27, 2020)

For best efficiency, cold water injected at the cold end should maximise heat exchange. But what burner and hot-end temperature do you expect?
What pressure will you have as NWP? Normal Working Pressure equals the point at which you will reduce fire and NOT EXCEED during normal useage. Even though you may run at a lower pressure, NWP is the pressure for designing and rating the boiler, safety valves, control system, etc. For safety, you must follow the regulations. (ASME). I'm sure it is law in USA and affects (possibly negates) your insurance.
K2


----------



## fcheslop (Dec 28, 2020)

You could try and contact this gentleman he is a member of this forum


			Flash steam hydroplanes Paul Windross


----------



## vederstein (Dec 28, 2020)

(Yeah, this thread is quite old)

My boiler is of monotube design.  A couple of notes:

1. The water inlet should have a check valve to prevent any steam back flow.
2. You must have a pressure relief valve.  Mine is set to 100 psi.  Have a pressure gauge as well.
3. A monotube boiler doesn't hold much water, so you'll be adding water constantly.  I suggest an automatic system.  My boiler controls run off an Arduino.
4. You'll need some type of indicator of water level.  I used a spark plug.  The water has enough minerals in it such that when the water reaches the spark plug, the gap is closed.
5. As steam bubbles form, they'll push water out with it.  Your steam will be interlaced with water drops.  My boiler has this issue and I've never fully fixed it.  I believe a superheater is important as well as a steam dome.  If I ever get a bug up my butt to build another one, this will be a significant improvement.
6. NEVER LET A MONOTUBE BOILER GO DRY!  The tubes will soften and possibly burst.  I have experience with this.  It's why my water controls are automatic now.
7. Feedwater pump must have run at a higher pressure than your boiler or no water will go in.
8. My boiler is propane fed and the burner is a turkey fryer burner.  With my arduino controls, I control the water level and the fire.  If the water is low, the fire goes to pilot light.  If the pressure is in range, the fire goes to pilot light.  The arduino also turns on the feedwater pump if the water is low.
9. Have a way to safely exhaust the boiler with a manual valve.
10. My boiler is only run once or twice a year for demonstrations, so mineral build up isn't really an issue.  When I'm done, I do run water through the entire boiler for a few minutes to remove excess minerals that may have built up.

New a view videos:

1 - Using a spark plug as a level sensor.
2 - An early test of the boiler.
3 - The boiler _almost_ as it is currently.  Since then I moved a pressure switch from the steam side (top) to the bottom where the water is cooler and then I can use more reliable and simpler pressure switches.  (I've posted this video here before).
4 - Dumb **** you can do with a small steam engine.

I guess that's it.

...Ved.


----------



## taterfarmer (Jan 9, 2021)

I'm  using  a hydraulic  cylinder on a metal frame for a water injection  pump. put together like a hydraulic  jack with a pump handle. 3/4" pipe and check valves. should  push around  a cup and half. 1500psi no problem .  I'm  using  steel tubing  in my monotube  boiler . 
aiming  for  500 + psi


----------



## Steamchick (Jan 11, 2021)

Hi Tater-man!
Is the 500psi the test pressure? - for 220psi Safety-valve lift? - or is it your planned NWP - for an Hydraulic test at around 1500psi test? (your pump limit). ASME design calcs for Hydraulic test pressure consider the stresses generated by the pressure at Normal Working Pressure against the UTS of the steel at a temperature relating to the temperature of the steam or superheat. In a monotube boiler, the UTS of the material in the hottest zone where the steam is being superheated can be significantly below that at "room temperature", so you will have to understand how hot the pipe will get at the hottest point... so you can determine a suitable "cold hydraulic test pressure". - Check ASME regualations for the rules.
Vedrestein.
I like the technicalities you explain..  but then I am amazed at the engines you are powering with wet steam at "low" pressure using such a large boiler. I have some similar sized engines that run (for demonstration) on an air supply using a small refrigerator compressor - at 10~15 psi. When steaming I always have superheaters in my boilers - if only to try and get dry steam to the engine - but for safety and good engineering ALWAYS use proper metal tubes for steam lines that are lagged to reduce heat losses and condensation. (I wind a double layer of thick string or wool around the pipe). 
Plastic pipe is OK  - within its designed pressure limit - for air-line. 
But plastic is dramatically weakened by the temperature of steam and I would not want to be in the vicinity of a broken steam line lashing around and blowing very hot wet stuff everywhere! One quick blast on skin or in your eye could be painful - or blinding! - An accident in the making I think? Please don't show potentially dangerous stuff on your videos... someone else may get hurt as a result.
Also, I was taught (as a young boy) that you must always blow steam through the engine while turning slowly to warm it and minimise the condensed water, otherwise after a few seconds running you'll develop an hydraulic lock from the condensate in the engine - and possibly damage the engine? Your vertical engine seemed to be hydraulic-locking?
Sorry to sound a bit like your mother - but please adopt safe practices.
K2


----------



## Steamchick (Jan 12, 2021)

Taterfarmer.
You could try this for information which applies to coil steam generators just as much as to "tank" boilers... becuase steam at pressure is just a dangerous, however you configure the boiler to generate steam. 
https://www.hse.gov.uk/pubns/indg436.pdf - see attached.

As you are in the US of A the Fedral rules will apply to you, not HSE, but they will be very similar, I think?
The ASME regulations actually apply to you, but my UK location doesn't seem to find those... 
I have been trying to understand guidance notes from various sources: the best guidance I can find considers coil boilers to be the same as superheaters and economisers for the sake of Regulation, so state that the ASME BPVC Section 1 applies - (Boiler and Pressure vessel code) - for "Equipment" and "Piping".
I think this is based on the water containing part being the same as an economiser, and the steam containing part being the same as a superheater, but check it out and decide for yourself.
Take care.
K2


----------



## Steamchick (Jan 12, 2021)

Hi Again Taterfarmer, I found a reference to a flash steam book: Experimental Flash Steam by J.H. Benson and A.A. Rayman. Any use? This long link should be to a copy for $18 in the US...


			Experimental Flash Steam book by John H. Benson
		

K2


----------



## Richard Hed (Jan 12, 2021)

Steamchick said:


> You could try this for information which applies to coil steam generators just as much as to "tank" boilers... becuase steam at pressure is just a dangerous, however you configure the boiler to generate steam.


Yes, Steam at pressure is dangerous, however, the two basic configurations: water tube and fire tube, are quite different in their dangerousness.  A fire tube heats an enclosed vessel filled with water, and when that water is heated to pressure it has all the mass of water behind it ready to expand when it can.  If a break in the vessel occurs, you have a huge repository of heated liquid/steam mass ready to escape.  If this steam escapes out a crack, it is bad, if it escapes by explosion, it is worse than disasterous.  However, if a water tube system develops a crack or worse, it is far less dangerous, as it USUALLY only develops a crack and it is contained inside the fire vessel (enclosed, that is) and the mass of heated water/steam is far less than the fire tube type.  This is why water tubes are used over fire tubes today.  The coil tube, of course, is of the water tube variety but a special type that heats the water very quickly.  Even so, it is contained in the heating enclosure and is most likely to develop pin hole type leaks.  Good for automobiles.

I see most of the toy pressure vessels we make, those of us on this forum, are of the fire tube type.  The vessels are usually very small, having less than a gallon of water and 30 psi or less--still enough to melt the skin off your face if the vessel explodes because of faulty work but small enough to probably not kill the whole block of people living in the area.  Even so, we want our vessels to be "original models", that is, to be miniatures of something we are copying/modeling.  As for myself, I would prefer to use water tube type regardless of keeping exact models.


----------



## Steamchick (Jan 12, 2021)

Thanks Richard. I understand your point. But all boilers that are correctly made to approved designs with certified materials and processes, and with the correct controls and trained operators and management, should be safe. I am in a Model Eng. Club that has 70 plus members. More than half run steam - either stationary models or locos on the track where we provide passenger rides to the public. I understand the club members have never had a catastrophic failure. In 25 years I only know of one incident where a boiler was difficult to keep in steam because the boiler had developed a leak. I think the boiler was over 40 years old. All the locos are 'tank' type, as are most of the stationary  and  road engine boilers. But all boilers are tested and certified as complying with regulations. So I am a bit suprised at any reluctance to use that type of boiler? Of course, there are operational differences with tank and mono-tube boilers. It just depends on "operational needs" for the steam, as to which is most suitable, in my humble onion.
Cheers!
K2


----------



## Richard Hed (Jan 12, 2021)

Steamchick said:


> Thanks Richard. I understand your point. But all boilers that are correctly made to approved designs with certified materials and processes, and with the correct controls and trained operators and management, should be safe. I am in a Model Eng. Club that has 70 plus members. More than half run steam - either stationary models or locos on the track where we provide passenger rides to the public. I understand the club members have never had a catastrophic failure. In 25 years I only know of one incident where a boiler was difficult to keep in steam because the boiler had developed a leak. I think the boiler was over 40 years old. All the locos are 'tank' type, as are most of the stationary  and  road engine boilers. But all boilers are tested and certified as complying with regulations. So I am a bit suprised at any reluctance to use that type of boiler? Of course, there are operational differences with tank and mono-tube boilers. It just depends on "operational needs" for the steam, as to which is most suitable, in my humble onion.
> Cheers!
> K2


Of course they are safe when built and operated correctly, I just thimk the water tube type are all round better  and safer.  I don't care about model exactness.  I thimk there was a boiler explosion on a ship in Portland, Oregon harbor in the late 1890's--not sure if it was Oregon or some where else, not sure about the date, but apparently the explosion took out a block sized space, kilt many people.


----------



## Steamchick (Jan 12, 2021)

Fair comment on Victorian history, without real quality control of materials design and manufacture, never mind training of operators, and management of boiler rooms, boiler maintenance, etc. 
I remember the 1960s when there was a traction engine (old then) and the stoker tapped the safety valve with a bit of metal... to let off some pressure. My Dad said it should work without being tapped! It was at some sort of fun fair (can't remember). But he led us away, and we couldn't  stay and watch it. Funny how memories come back?
K2


----------



## Richard Hed (Jan 12, 2021)

Steamchick said:


> Fair comment on Victorian history, without real quality control of materials design and manufacture, never mind training of operators, and management of boiler rooms, boiler maintenance, etc.
> I remember the 1960s when there was a traction engine (old then) and the stoker tapped the safety valve with a bit of metal... to let off some pressure. My Dad said it should work without being tapped! It was at some sort of fun fair (can't remember). But he led us away, and we couldn't  stay and watch it. Funny how memories come back?
> K2


Well, tht reminds me, (I wasn't there in Portland when that ship blew), In 1913 when Stravinsky in Paris on opening night with The Rite of Spring, I had managed to get a perfect seat in gthe audience.  soon after the music started, someone yelled "Booo", a couple minutes later someone else burst out laughing, then the boos started.  Someone else yelled "Shut up, I want to see this", soon, a riot broke out.  I crawled out of the theatre, thimking that I would return tomorrow.  Well, the police were called to put down the riot in the theatre and the band played without missing a beat and the dancers not missing a step.  The next day, I went early to get in line for tickets and it was a good thing I did.  For in a few minutes the street was filled with persons trying to get tickets.  Altogether 10,000 people showed up as the riot last night was reported in the papers and the public wanted in on the fun.  I managed to get my ticket and get in the theater just in time to see the 10,000 start another riot.  The police were called in again.  So much for explosive situations, just a little music boiling a little too much.

Of course, this all pleased Stravinsky a great deal.


----------



## Steamchick (Jan 13, 2021)

Hi Richard, While I enjoy tall tales, if you were born in 1913 you would be 106 years old. Not unreal, just rare...
But for you to go "early to get in line for tickets " suggests you must have been at least 14... so that puts you about 122 years old? - So did you serve in the Great War? A couple of my teachers did. 
Are you sure you are not simply recounting another's tale? - you look younger in your photo! And the tale reminds me of a tale my Grandfather told me - but I thought he said it was New York. But the records show you are right, it was Paris, so maybe he was just recounting a tale?
The riot at the Rite: the premiere of The Rite of Spring
He had sailed on the RMS Titanic, but in 1913 was on the RMS Olympic doing the New York run... having transferred from Titanic's working-up trials off Belfast,  just a couple of weeks before Titanic sailed her maiden voyage, as his oppo on the Olympic went sick. He wrote in his journal how sick he was to miss the first trip on Titanic! - How lucky I am that he didn't! He was "4th Eng'r." running the Dynamos... - And that's NOT a tall tale.


			https://www.amazon.co.uk/Nice-Quiet-Life-Merchant-through-ebook/dp/B00QO3WND4
		

While he did sail on many ships that foundered, I am sure he never experienced a boiler explosion! But his Father was the Lloyds Boiler Inspector for all the boilers manufactured in Sunderland, so maybe that influenced him to safe practices?
Our history is written, but we must write our future.
K2.


----------



## Richard Hed (Jan 13, 2021)

Steamchick said:


> Hi Richard, While I enjoy tall tales, if you were born in 1913 you would be 106 years old. Not unreal, just rare...
> But for you to go "early to get in line for tickets " suggests you must have been at least 14... so that puts you about 122 years old? - So did you serve in the Great War? A couple of my teachers did.
> Are you sure you are not simply recounting another's tale? - you look younger in your photo! And the tale reminds me of a tale my Grandfather told me - but I thought he said it was New York. But the records show you are right, it was Paris, so maybe he was just recounting a tale?
> The riot at the Rite: the premiere of The Rite of Spring
> ...


Well, I was just a little tyke when I got to see the battle of Shiloh from a hilltop.  I remember it well.


----------



## Steamchick (Jan 13, 2021)

Hi Richard,
And there was I hoping I was really talking to Methusalah's brother! You would be older than Goldstar!
If only our genetic heritage could capture memories from our ancestors... - but even then we could only inherit memories of youth and love. None of the memories of ageing and off-spring growing-up, work, adult stuff and retirement.... So maybe that is not such a bad thing?
But some of my favourite memories are things told me by people older than my parents, when I was a child. That folklaw has more veracity than "modern politics and the press"! - But that is another topic!
Cheers mate!
K2


----------



## goldstar31 (Jan 13, 2021)

Richard Hed said:


> Of course, this all pleased Stravinsky a great deal.





And here was me enjoying Shakespeare's Midsummer Night's dream in the middle of yet another pandemic.
But for those who want to grasp anything about the Rite of Spring, might I suggest that you  witness a variation on it from Walt Disney's Fantasia.
Of course if you think about the Spring of1913 anf then  Spring 1914, you are  looking at the death of the Archduke Ferdinand-and we know what happened- or do we?

Well history does repeat itself?  So Richard - your story please


----------



## Richard Hed (Jan 13, 2021)

goldstar31 said:


> And here was me enjoying Shakespeare's Midsummer Night's dream in the middle of yet another pandemic.
> But for those who want to grasp anything about the Rite of Spring, might I suggest that you  witness a variation on it from Walt Disney's Fantasia.
> Of course if you think about the Spring of1913 anf then  Spring 1914, you are  looking at the death of the Archduke Ferdinand-and we know what happened- or do we?
> 
> Well history does repeat itself?  So Richard - your story please


Of course, just for you.  So I went several times to the Rite and got used to that supremely strange music and was enjoying Paree when the Archduke was killt.  We all thot it would blow over, but later we found that certain international banksters WANTED war--$$$$.  I didn't want to join up when the war came, but I had to defend gay old Paree so I did join up.  It just so happened that the unit I was in had a captain that I had known on the outside.  He hated me ferociously, for why, I never knew, probably because of my humility and good looks and smarts too, of which he was most likely jealous.  

I saw him first so fastidiously hid from him but eventually he spotted me in his company and I was partially undone.  After that, I was put into the dirtiest and most dangerous positions he could put me.  Oddly, he was poorly liked by all and one day in the feild when he had given us a particularly odious order of passing over an open field which the huns had their new water cooled machine guns trained on, an order which we could easily have avoided those guns by going thru the trees which surrounded the field, an order which was both incompetent and suicidal to perform . . . well somebody fragged the bastud--and it wasn't me but truthfully, I was relieved at that.  A leuitenant took over and we went thru the trees, taking a couple casualties.  We were turned back because of the machine guns but the next day . . .


----------

