St George

[corydoras]

Komodo dragon apart, slaying a monitor lizard is more an act of foraging than of heroism!

 

"And this is Saint Tiggywinkle, who slayed a giant ferocious land hog, covered in prickles it were, and turning people to stone with its little beady eyes. He is depicted eating some kind of meat baked in clay"

I would not like to mess with a perentie either. Mind you I doubt that George ever stumbled across one.

[corydoras]

I spent several years taming, tending and riding the descendants of Trevithick's dragons. Stirring stuff !

Have you given up driving locos then Dave?

[Vagabond]

Have you given up driving locos then Dave?

Yes, my increasing deafness saw to that.

 

Steam locomotives are potentially very dangerous, and it is only the skill and vigilance of locomotive crews that keep them safe. One piece of that vigilance involves listening very carefully to what sounds the loco is making.

 

One instance (out of many, which I won't bore you with)

It is essential that the water level in the boiler is kept above the crown of the firebox or the firebox crown melts and the boiler goes off like a bomb. There is however, a "safety" device whereby a fusible plug melts first, and the boiler water is thus forced into the firebox at high pressure, which puts out the fire and saves the bystanders from an explosion - merely scalding the loco crew - often fatally.

The water level also has to be kept below the level of the steam pipe leading to the cylinders, or else incompressible water gets drawn into the cylinders, so that the moving piston meets an immovable object (water) and something has to give - not funny if the loco is travelling at speed.

 

To keep the water level between these two extremes - (which are not very far apart !), there are devices called injectors, which use steam to squirt water into the boiler - to replace the water converted to steam to make the loco go.

Injectors are temperamental chunks of equipment, and sometimes require very fine tuning to get them to work - good hearing is essential in that tuning, When working a loco, turning injectors on and off and adjusting the rate of flow of both water and steam is a fairly frequent activity.

 

When I noticed I had difficulty hearing what I needed to hear, I took myself off the footplate. To stay would have been irresponsible.

Edited April 24, 2014 by Vagabond

[rob.imk2]

I hope you guys are not saying The soup dragon and the ice dragon dont exist

[Andrew]

I hope you guys are not saying The soup dragon and the ice dragon dont exist

 

They are blasphemers, pah may the soup dragon spirits give the non believers nightmares.

 

Looks like the toic has strayed onto loco's mate, nowt to do with dragons now, LoL LoL

[Vagabond]

strayed onto loco's mate, nowt to do with dragons now, LoL LoL

A working steam loco is as near a real dragon as you could meet. Try firing one!

[corydoras]

It is essential that the water level in the boiler is kept above the crown of the firebox or the firebox crown melts and the boiler goes off like a bomb. There is however, a "safety" device whereby a fusible plug melts first, and the boiler water is thus forced into the firebox at high pressure, which puts out the fire and saves the bystanders from an explosion - merely scalding the loco crew - often fatally.

The water level also has to be kept below the level of the steam pipe leading to the cylinders, or else incompressible water gets drawn into the cylinders, so that the moving piston meets an immovable object (water) and something has to give - not funny if the loco is travelling at speed.

I'm surprised that some bright spark never invented some device to automate that process.

Edited April 24, 2014 by corydoras

[Steve Walker]

I'm surprised that some bright spark never invented some device to automate that process.

Perhaps loco crew were more reliable (or cheaper!).

[chesters1]

A working steam loco is as near a real dragon as you could meet. Try firing one!

Dragons live in one

 

Seen in this rare documentary

D

Edited April 24, 2014 by chesters1

[Vagabond]

I'm surprised that some bright spark never invented some device to automate that process.

It's MUCH more complicated than just setting a constant feed. Railway lines go up and down hills. Think of the implications of the water level in a tilted boiler when it goes over a summit - and think also of the variability of the amount of steam required for different parts of the journey.

 

Engine crews must "think ahead" all the time - if you need more steam, the coal needs to be in the firebox ten minutes ago !

Coal quality varies, so a fire must be watched and weak spots repaired before the loss of heat leads to loss of steam pressure,

OTOH you don't want too much steam at the wrong time - wasting steam through safety valves is expensive - so you put more water in to cool the boiler - if you have had the forethought to have left enough room to do so !

 

Water quality varies - some water will foam easily when heated, with the danger of water getting carried over to the cylinders.

 

Far too many variables to entrust to automation in the days when human brains were the best computers available.

 

(In many cases they still are - I can still beat in-flight chess-playing computers without too much trouble - only the cutting edge of computing can produce a program to defeat a good club player)

 

PS ...and to top it all, two engines of the same class with identical dimensions in theory could well demand two quite different approaches to get the best out of them.