racerfrank wrote:
Is it possible to get an accurate psi reading at the valve chest? I would assume that the pressure fluctuates quickly as to make a gauge needle "flutter".
Frank
IHP uses mean CYLINDER pressure. Steam chest pressure is isolated from the cylinder pressure at cutoff and therefore the cylinder pressure at the end of expansion is not accounted for at the valve chest. Even if you could average the valve chest pressure it's not what you want to use in the calculation.
"I will be going with some form of Uniflow arrangement with a mono tube boiler."
Monotube boilers and variants thereof needs some sort of automatic controls and are really best fired with a liquid fuel that can be turned off and on quickly. They work in cars because they are fired with liquid fuels and on some electricity is available to control the boiler with solenoid valves, quartz rod thermostats etc. And White had the ingenious non-electric flowmotor design that worked well. The Doble steam car which is all electric controls, cycles the burner off and on 5-10 times per minute depending on demand to provide stable supply. They can be flooded resulting in carryover (water to the engine) or ran dry very easily resulting in coil failure. Monotubes are for experimental or complex systems.
Trying to fire one with wood on a boat and attempting to maintain a steady pressure manually would be about impossible. And too, whatever goes in a monotube comes out the other end - to the engine.
Even some of the watertube types with reservoirs are difficult to maintain due to the small reserve of water. I personally like the Ofeldt as a watertube type. Small dimension, suited to round burners and fireboxes, adequate reservoir for stability, very good internal circulation, easy to build.
Nothing wrong with Firetube boilers for good stable steady steaming on a launch. All boilers can potentially be safe or dangerous, that is up to the person operating and maintaining them. Annual hydrostatic testing, Ultrasounding, visually inspecting the internal surfaces all fall under the heading of boiler maintenance. It is as safe as it is handled.
The units I work with will move water at 6 GPM, 3000 PSI @ 250 degrees. The bigger of the two machines will move up to 10 gallons a minute. Both can be run as live steam generators for cleaning or just hot water for light duty cleaning. The Landa is made here in the states and the Karcher is Italian.
I use a temperature/water pressure gauge setup to adjust these machines when I have repaired them and have seen the temperature rise well over the 300 mark and literally melted non steam rated double wire pressure hose.
I have one Karcher that had a blow out in the coil near one end. The flow switch stuck on again and the employee was not paying attention. The burst disk had already blown earlier in the day but instead of bringing it back to the shop so I could figure out why he just pulled it off and installed a pipe plug.
I swear every time I try to make the equipment "stupid proof" they come up with a "smarter stupid"!!
The flow switch typically gets flakes of rust on it and the plunger sticks in the bore. It does not help that the plunger has a magnet in it to activate the reed switch. But I have yet to find a reliable switch to replace it, so we depend on the burst disks to pop when things go really wrong.
I will take some detailed pics of the coil that was removed from the case. I am not sure how long the coil is, I will try and find that info for you. The damaged coil I was going to cut down and use as a pre heater or super heater.
I got another question for you... Is there some significants behind using a right hand prop over a left hand?
Cyruscosmo
My Grandpa told me when I was 8 or so that “You have to learn by the mistakes of others! Because you will NOT live long enough to make them all yourself.” At that age I though I had forever to learn everything...
"Is there some significants behind using a right hand prop over a left hand?"
I think this is just a strong tradition, perhaps a standard years ago, where the better crosshead bearing area is loaded running ahead with a right hand prop?
Many engines are designed with no preference as to the running direction of the crosshead slipper, so it really does not matter technically right or left propeller.
I agree with most of what Ron (Detroit Tug) says about monotube boilers, especially about needing a controlable fire, which implies gas or oil firing. However my monotube design runs with constantly flooded coils, so burnout will not occur, and close control is not needed. That setup, running my first steamboat, worked well, used no electricity, and had no special automatic controls. The plant did not have a wide range of output, only about 2:1 turndown, which worked OK on a small boat. See Radow Rainer's website under "Scanoe Steamboat"
All this talk of monotone boilers and controls and such . . . .
Do you want to go steaming or mess with your power plant all of the time? There is some overlap but less than you might think.
I know of one (count it, one) boat that has a complicated power plant that gets much real use. Wes's boat. And it took a lot of sorting out over many years to get it that way.
As an aside, the notion of trying to fire a monotube with solid fuel is surely the precurser of a wonderful YouTube video. Out of control!!!
If you think you are too small to make a difference, try sleeping with a mosquito.
Dalai Lama
LOL Hello Mike!
No I was leaning more towards using all this free waste oil I have. And yes I do like to tinker. If all I had to do was turn the key and putt around the sound you would find me bored to death, or asleep at the wheel. That said I am not entirely sold on the mono tube or the LaMont or just good old wood. I do know that I want something that has a fair amount of fiddling to go with it which is why I chose steam instead of diesel. Lots of interesting goings on in the engine department. Maybe I can hitch a ride with you one of these days. I live in Woodinville.
Ok Fred I got some pictures for you today. These are of the burst coil out of the smaller heater we use. One of the pics shows the hole. It was a shame too as this burner was barely a year old.
[img][IMG]http://i12.photobucket.com/albums/a222/ ... vyacyb.jpg[/img][/img]
I am not sure how long the total tube length is. I got the measurements shown so you can throw some math at it if you like.
Cyruscosmo
My Grandpa told me when I was 8 or so that “You have to learn by the mistakes of others! Because you will NOT live long enough to make them all yourself.” At that age I though I had forever to learn everything...
As to fiddling, I probably have the simplest power plant afloat (And the ugliest hull!). It is a single cylinder piston valve engine fed by a VFT boiler. No feed water heater, economizer, auxiliary feed water pump or injector. The closest thing to complication is a hot well float. I have an ordinary Hypro feed water pump running off of the end of the crank shaft at engine speed and a hand pump that hasn't been used other than for hydro tests.
And I am ALWAYS fiddling with stuff when under way!
Now I may add a few fun things in the future. I have an almost completed duplex feed water pump that I have no need for but am in love with. Other things like a feed water heater and economizer may happen. But they had better not get in the way of navigating and being a good host.
Yes, I will have Folly on the mainland sometime after the 4th. of July and I will be certain to make connections with you. Any time you want to park your car in Anacortes and visit Lopez you will be more than welcome. Stephanie has Uno almost ready to steam and Folly is parked a quarter of a mile from the launching ramp with bags of wood filling the bow. It takes very little to entice me away from persecuting old growth dandelions.
If you think you are too small to make a difference, try sleeping with a mosquito.
Dalai Lama
And by all means, come to the Northwest Steam Society Annual Meet at Cathlamet, WA August 7 through 9, 2015. There'll be lots boats of different sizes, shapes, and power plants. If you're not a member of the NWSS, go to: http://www.northweststeamsociety.org and select the "2015 meet" button from the navigation column on the left. Bring all your questions.
I will make sure that date gets on my calender. The last time I seen a steam launch in person was the woodin boat show in bremerton about 20 years ago. I wanted to go for a ride but the owner was nowhere to be found the whole time I was there. I did get to go sailing that day, actually had a blast for my first time under sail. By the time we got back to the docks the steam launch was gone.
Hey Mike why do I have to leave my ride in Anacortes? That island is not so small that it has no roads is it? It would be a nice motorcycle ride for the day.
Hey Fred about those pictures I linked for you. I found a place that says the coil is 125 feet long and is rated for 250 Bar. I was thinking about cutting out the center section of the coil to get rid of the hole in the tube and using the rest as a "water wall" section in a LaMont type mock up. I found some information on a set up that someone had for a steam car. They had a circular fire chamber in the bottom of the box sorta like the setup Bart has. I wanna see how hard it would be to make the fire box interchangeable with a grate for burning wood. There is a boiler built like that on Raniers site http://www.steamboating.de/steamboat/st ... ect=boiler
The fire box would be pretty easy to make interchangeable.
How big can the Tube be before it is considered a Boiler? The Lamont has a small tube for a water tank/steam dryer. Would that part have to be made by a boiler maker? http://www.stanleysteamers.com/lamont-1.htm
Cyruscosmo
My Grandpa told me when I was 8 or so that “You have to learn by the mistakes of others! Because you will NOT live long enough to make them all yourself.” At that age I though I had forever to learn everything...
![[IMG]http://i12.photobucket.com/albums/a222/ ... vyacyb.jpg[/img]](http://s12.photobucket.com/user/toejaminearl/media/IMG_0521_zpsw2vyacyb.jpg.html){kind=link}