While watching the video of a full scale replica of a class A Climax another member posted a link to in the "Smallest Heisler" thread, I began to consider, "what is a locomotive boiler?" This may be a more relevant question than ever considering there is an ASME committee establishing rules for locomotive boilers. The class A Climax had a vertical boiler on it. Some park trains and large scale live steam locomotives have Briggs boilers (looks like a traditional locomotive boiler but has no water legs around the firebox). The little 0-4-0 the folks in Nevada built has a coil steam generator on it. Are these locomotive boilers because they are attached to locomotives? What about tractors? What about 7 1/2" gauge live steam engines? What about steam powered automobiles?

What does the community think?

S.O.

anything that produces steam from heating water for propulsion?

I recall riding a Stanley Steamer auto years ago at a steam threshers reunion.

Engine 10000, a 4-8-4 preserved in Philadelphia I think uses a watertube boiler with pressure up to 600 psi, its moved back and forth from time to time as demonstration, non-powered. There was an article in one of the mags about it demonstrating it and the engineer to run it looked at the Steam Gauge and got off.... 8-D

One of the operative words, " style ", is missing from the title.
To Wit:
...incorporating a water jacketed firebox with flat stayed surfaces, supported and braced against expansive and collapsing forces due to pressure by staybolts...

You can add a firetube section, a watertube section, a reverse bend, a third pass, no doubt, someone will remind us here shortly. Getting away from that water jacketed firebox with flat stays, and we'll have a different sort of duck, IMHO.

Agreed - semantics aside, the "locomotive boiler" term as common usage refers to the old reliable kind we all know and love (until it needs heavy work, anyhow). I've seen the term applied to boilers of similar style of construction installed in stationary and marine applications. You talk to an old boiler guy, and tell him you have a locomotive style boiler powering your machine shop, he'll know what sort you are describing. Other types applied to locomotives are generally considered "experimental" types on the railroad, might have other names in other places.

dave

As defined in an International Correspondence School handbook I own, a "locomotive type" boiler is the traditional boiler with a water jacketed and stayed firbox and a single-pass set of flues running through the water space to carry the combustion gasses to the smokebox. Vertical boilers are essentially considered a variation on the locomotive type boiler.

The locomotive type boiler has been used on steam traction engines, steamships, and in stationary applications. It's main advantage in applications other than locomotives is that it is essentially a self-contained boiler, requiring a minimum of supporting structure and/or firebrick mounting when compared to a typical water-tube type.

As noted, locomotives can have different types of boilers, including the traditional locomotive type, a variation with a water-tube firebox (Emmerson and McClelland experiments on the B&O and New Haven respectively), Schmitt multi-pressure steam circuit boilers (NYC and CP experimentals, also tested on the LMS in Great Britain), full marine tube types (LNER experimental 4-6-4, N&W's Jawn Henry steam-turbine-electric and Union Pacific's two GE-built experimentals). A number of small locomotives have used return-tube or return flue boilers, among them a tiny engine that ran on a Nickel Plate predecessor in the 19th century, and apparently the tiny Heisler 4-wheeler in the "smallest Heisler" thread. This configuration was common in marine and stationary applications, one variation being known as a "Scotch" boiler, and its main advantage was a comparable firetube length to the locomotive type boiler in a little over half the overall length, which could be an important consideration in some cramped locations. Generally speaking, most did not work well in locomotive practice, suffering from leaks and other problems that arose from being mounted on a bouncing, vibrating, twisting frame instead of a solid masonry foundation in a power plant or deep in the stiffest part of a ship's hull.

The engine in the Franklin Institute in Philadelphia is a Baldwin demonstrator numbered 60000, and is a three-cylinder compound 4-10-2 with a 350 psi water tube firebox boiler.

http://www.steamlocomotive.com/3cylinder/#60000

http://www.cwrr.com/Lounge/Reference/ba ... ldwin.html

Those little Stanley steamer boilers are interesting little animals. They are essentially a vertical firetube boiler with wire wrapping to reduce weight and stand up to a working pressure of almost 600 psi! The wire wrapping was a technique borrowed from military gun manufacture, and was invented by the Stanley brothers for that original military application. They also invented a number of automatic controls for those little boilers as well.

http://en.wikipedia.org/wiki/Stanley_Steamer

http://www.jaylenosgarage.com/video/cat ... ars/30507/

http://www.stanleysteamers.com/

http://www.stanleymotorcarriage.com/

http://www.stanleymotorcarriage.com/Par ... ctions.htm

My only closing comment is to say I wish I had Jay Leno's money--what a collection of toys!

Enjoy!