On Sat, 16 Jul 2011 01:09:32 -0700, harry wrote:

On Jul 15, 10:16Â*pm, Gib Bogle wrote:
On 7/16/2011 12:54 AM, Andy Breen wrote:

On Fri, 15 Jul 2011 05:05:17 -0700, Matty F wrote:

shurely shome mistake

Boilers are not cast iron just for starters

Not (usually..[1]) in locomotive applications for many years, but it
was the standard material for many boilers - including locomotive
ones back in the earlies.

The first commercially successful locomotives - and the first
exported - had cast iron boilers, after all..

Pretty hard to cast a boiler, shirley?

No they were very common for low pressure steam heating of buildings pre
WW2 especially in America,
The technology is still in use but only for water boilers.

They use similar technology to cast iron radiators. Trevethicks first
loco in Merthyr Tyfil had a cast iron boiler apparently. But it was very
low pressure.

Between 35 and 50 psi are the figures I've seen quoted. These were very high
pressures for the day (and would remain respectable for another 35-odd years
in railway applications).

The thing only ran at 2mph.

It was geared down for low speed. Hauling unsprung waggons on plate rail,
you'd not want to go faster. Speeds of 3-5mph or so were typical for plateway
locomotives, certainly as long as cast-iron plates stayed in use (say
1850s at Dowlais). You'd not want to go faster, given that you needed to carry
platelayers on the train to replace the rails that had broken under you..

It's often forgotten that the Pen-y-Darren machine was not designed as a
locomotive, but was an adaptation of a multi-purpose stationary engine.
Nonetheless, it managed the longest continuous run undertaken by any
locomotive until 1825..


--
From the Model M of Andy Breen, speaking only for himself