The Steamboating Forum

Just a thought that I've been on many, small boats with VFT boilers with no steam drier. Just take the steam off as near to the top as convenient and set up your sight glass so that the top reading is far enough below that. With the damping effect of all those fire tubes and perhaps taking the engine steam off near the center line of the boiler one shouldn't have a problem. The water should only get to sloshing if the boat motion and the 'slosh' frequency coincide. I must rock my boat the next time I'm out and see if the glass shows a natural resonance.

The is an entertaining but friendly divide within the steaming community between wanting all systems as close to full sized practice as possible on one side and the sort of 'African Queen' mentality that wants to have things safe but would rather kick things once in a while and spend the rest of the time relaxing and singing a la Bogart.

Both notions coexist in the same head for most of us. I love to look at high tech stuff but lack the drive to deal with it. I prefer to explain to the nearest Chinaman (read: Enthusiastic passenger) the difference between 'dead steam' and live steam and leave the 'Devils in the Boiler' to deal with the rest.

Regarding a slug of water in the steam line, a steam chest and D-valve are inherently designed to deal with it. The steam chest act as a trap and the D-valve theoretically should lift off the valve face from hydraulic force. An advantage over a piston valve.

Considering steamboats and steamcars in the same conversation, the attitudes and methods of each are at stark contrast. We steamboaters use these big heavy boilers, schedule 80 this and that, and consider anything over 100psi rather high pressure(I do anyways). After hanging around in the steamcar circles, it's a bit surprising from that side of the fence. These guys take monotubes up to close to a 1000psi routinely. The Stanhope I rode on last summer with an Ofeldt - he doesn't even take off until he hit's 275 psi. And we were sitting right atop the boiler.. Oh yeah and don't forget the 5 gallons of gasoline in the other tank at 75 psi on the same vehicle. I sure wouldn't want to break a fuel line.

I heard a story that very thing happened on a Stanley bus a few years ago, burned it to the ground.

-Ron

I kinda liked that scene in The African Queen where the rifle bullet knocked loose the steam line and he wrapped it with some tape or something. I need some of that tape!

Maybe the biggest howler in the movie.

Lopez Mike wrote:Just a thought that I've been on many, small boats with VFT boilers with no steam drier. Just take the steam off as near to the top as convenient and set up your sight glass so that the top reading is far enough below that. With the damping effect of all those fire tubes and perhaps taking the engine steam off near the center line of the boiler one shouldn't have a problem. The water should only get to sloshing if the boat motion and the 'slosh' frequency coincide. I must rock my boat the next time I'm out and see if the glass shows a natural resonance.

One other thing you can do is fit an elbow inside the boiler at the outlet. if the elbow faces upwards, the water 'slosh' has to get above the level of the outlet before it can get into the steamline. It also means that the steam is being taken from as close to the top of the boiler as possible. On Zeltic both the main steam and safety valve outlets have elbows on them. Hers is a 3 foot high vertical with sight glass is the middle third of the boiler, and even in big seas carryover has never been a problem, even with a high glass, although i tend to run a lower water level in the big stuff just to be safe.

Daniel

Greetings,

Thank you all for the separator information. I think I'll just take the main steam out of the center of the boiler. I'll just be chugging around on the St. Criox river, not much wave action there so I shouldn't have to worry about priming. Plus having the main pass through the smoke hood should dry the steam somewhat. Though I'd be kinda worried about heat stress on that section of piping.

This weekend I found a steel supplier right in the town where I live. Next weekend I'm going to stop by and pick up some stock for some engine components and get started on that. They also have some 18" pipe with a 3/8" wall so I may get my boiler shell while I'm there as well.

Toodles
Josh

I wouldn't think there would be that much heat stress in the stack. The gasses have cooled a lot by then. And steel is fairly tough stuff. You might try to have the dry pipe connections be welded rather than screwed together when possible though if a pipe thread is well and truly socked down tight, it isn't that dependent on sealants.

On locomotive boilers the stay bolts sometimes weep a tad at first but good old rust closes them up before long.

I wouldn't know how to act around a steam plant that didn't do at least a little hissing and dripping somewhere.

Hey, so here is the main steam line



It would be a 1 1/2" vertical section of Sch 80 going from the boiler fitting to a elbow and to another length of 80 going horizontal out the smoke hood to the main steam isolating valve.

Should I have any problem steaming with this boiler I'm using the Hasbrouck #10 engine?

I'd like to pick up the shell this weekend.

Hope to hear from you soon,

Josh

Seems like a lot of trouble to take the steam off in the middle of the upper tube sheet like that. On most of these donkey boilers like this the steam to the engine as well as the fittings for the pressure gauge, whistle and safety valve are just welded in as near to the top of the shell as i convenient. That way everything that might go wrong or need changing is right out where you can get at it. Also, that pipe run you have drawn in will get in the way of replacing some of the tubes down the road.

Being able to work on things and diagnose leaks is a lot more important than a little bit of superheat. I wouldn't try to re-invent the wheel on your first boiler. You will have enough trouble with nickle and dime stuff without asking for complicated leaks.

So just stick with the original placement location?

Yes, stick to putting the fittings in the side of the boiler. By not taking out of the middle of the boiler, you'll gain an extra tube, which will be far more beneficial than the little bit of drying you gain from the steam pipe. That pipe (inside the smokebox, and thus corroding from the inside and probably rapidly from the outside), would be far more trouble than its worth.

Stick to conventional practice, and if you are remotely worried about carryover, fit an elbow inside the boiler as per my previous posting.

Daniel