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Post by niels on Nov 19, 2020 16:26:32 GMT
So a 240v genny in the riding car powering a small immersion heater in the loco would be out then. Not nessecaryli but big and heavy.The 5 inch gauge Peverill(My favourite) made 220Watt between wheel and track at the IMLEC 2019 and efficiency coal to traction was 1.3%.An electric boiler can have better insulation and do not send out lukewarm exhaust.Let us say 2% then and the electric heater then needs 11kW.
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Post by RGR 60130 on Nov 19, 2020 16:41:39 GMT
One of the disadvantages of an electrically heated boiler is that it will only generate saturated steam so you need to be careful when comparing to IMLEC contestants who may be using super heaters over the fire.
Reg
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mbrown
Elder Statesman
Posts: 1,713
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Post by mbrown on Nov 19, 2020 19:08:23 GMT
Somewhere in an old copy of The Locomotive Magazine, I have a short article about a shunting loco driven by steam - heated electrically from the overhead supply. It was in Switzerland? or Austria? or somewhere like that, and I believe it was a response to a coal crisis - they knew it was inefficient, but it was a case of needs must.
It will take a while, but I will see if I can find it and post a scan.
Malcolm
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Post by delaplume on Nov 19, 2020 20:40:22 GMT
Cyclopede? One horse power... Malcolm Yep !!---------- a real "One horse race"....
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Post by andyhigham on Nov 19, 2020 20:51:54 GMT
Back in the day there would have been 2 reasons for a fireless loco A large quantity of steam "on tap" The need for cleanliness on food factories, example the Bagnall fireless locos at Huntley and Palmers
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Post by andyhigham on Nov 19, 2020 21:15:41 GMT
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Post by steamer5 on Nov 20, 2020 0:01:34 GMT
One of the disadvantages of an electrically heated boiler is that it will only generate saturated steam so you need to be careful when comparing to IMLEC contestants who may be using super heaters over the fire. Reg Hi Reg, Maybe get around that by having both an immersion heater & a radiant heater in the fire box, maybe? Cheers Kerrin
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Post by delaplume on Nov 20, 2020 1:07:09 GMT
Back in the day there would have been 2 reasons for a fireless loco A large quantity of steam "on tap" The need for cleanliness on food factories, example the Bagnall fireless locos at Huntley and Palmers Plus the safety factor}----- Flour dust is highly combustible.... Mum worked at H&P's right up to their relocation to Huyton, Liverpool.........She'd quite often bring home a bag of broken biscuits from the staff shop on a Friday afternoon.......
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jackrae
Elder Statesman
Posts: 1,333
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Post by jackrae on Nov 20, 2020 8:17:55 GMT
The Manchester museum appears to be in error by stating "A fireless locomotive is similar to a conventional steam locomotive, except that the ‘boiler’ was in fact a large pressure vessel which was replenished with steam at intervals from the factory mains." These locos were replenished with high pressure hot water, leaving a relatively small steam space under the steam dome. As the steam was drawn off the reduction in pressure caused further steam to be released from the hot water.
Museum curators really should be taken up on their errors as they 'mis-educate' the public with false information. When I last visited The Greenwich Maritime Museum there was similar mis-information on it's torpedo display
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Post by andyhigham on Nov 20, 2020 9:13:33 GMT
Are you sure? As water is incompressible it cannot exert pressure, it a boiler the pressure is exerted by the steam Boiling water cannot exceed 100 degrees C, in a boiler the pressure of the steam stops the water boiling until it reaches a higher temperature. I would suggest the fireless loco is charged with high pressure steam which condenses in the pressure vessel. Most factories would have had a steam supply. A hot water supply would have needed to be piped from the bottom (coldest part) of the boilers. The loco would need to be right next to the boiler for charging unless there were circulation pumps for the hot water, otherwise after a short while there would be a dead leg full of tepid water
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Post by chris vine on Nov 20, 2020 9:24:48 GMT
Hi Andy,
Sorry if I have misunderstood your post but,
Yes, water is pretty incompressible, but it can still exert pressure. for example in hyrdraulic rams. In the fireless "boiler", the pressure in the steam and water will be the same. The temperature of the boiling water goes up with the pressure. So that, from memory, at 120 psi, the saturated steam (and boiling water) will be at 175 C. In the fireless engine, if you extract steam without adding heat, the temperature of the water/steam will drop so that the pressure drops as well. Once you get down to 100 C, the pressure will be atmospheric and the locomotive will do no more work!
You could still describe the pressure vessel on a fireless locomotive as a boiler, I think, because as the steam is taken off, the water boils (as it temperature falls) to replace the steam... Chris.
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mbrown
Elder Statesman
Posts: 1,713
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Post by mbrown on Nov 23, 2020 22:17:51 GMT
I mentioned in an earlier post ion this thread that I recollected an electrically heated steam locomotive somewhere in Europe Well, here it is - as reported in The Locomotive Magazine for 15th January 1946. It was indeed in Switzerland, during the War when coal was scarce. I hope the photos are legible. IMG_20201123_220843 by malcolm brown, on Flickr IMG_20201123_220915 by malcolm brown, on Flickr As sort of cross between Roger's electrically heated test boiler and a Rob Roy, Simplex or similar tank loco! Malcolm
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Kevan
Seasoned Member
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Post by Kevan on Nov 24, 2020 7:53:29 GMT
Hmm certainly an idea though not sure how I could persuade the club to put in the overhead supply! The consequent burn marks on people’s hats and compulsory centre partings for those of us still with some hair would probably not go down well with other members🤣
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Post by keith1500 on Nov 24, 2020 10:16:18 GMT
That’s an interesting article. I knew off these locos before and seem to recall one at a model engineering exhibition, or did I imagine that?
But, Any way, what caught my attention was the fact they could be coal fired in places where the overhead supply was not. So the modification was well engineered to slot into the existing boiler. It does make you wonder what the effect of drafting would have been. Presumably working against the electric heating by pulling cold air through the tubes.
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Post by delaplume on Nov 24, 2020 11:10:43 GMT
Hmmm.......High tension Electricity, water and 2 humans all in close proximity to one another !!!......some might call that situation "Shocking"....LoL !!
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Post by ettingtonliam on Nov 24, 2020 12:23:10 GMT
Would be interesting if there were ever any published comments from the guys who actually drove the things.
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pault
Elder Statesman
Posts: 1,496
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Post by pault on Nov 24, 2020 13:11:01 GMT
Hmm certainly an idea though not sure how I could persuade the club to put in the overhead supply! The consequent burn marks on people’s hats and compulsory centre partings for those of us still with some hair would probably not go down well with other members🤣 I'm sure it would be fine, have a looks at to see how it can be done. They even have pulse width modulation for speed control www.youtube.com/watch?v=unhXEQQk8G8
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Post by ettingtonliam on Nov 24, 2020 13:44:41 GMT
Thats scary! Wonder what voltage they were using?
Love the points though.
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Post by delaplume on Nov 24, 2020 20:20:22 GMT
Anybody remember "Daddy Longlegs" at Brighton beach ?>??
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Post by andyhigham on Nov 24, 2020 20:37:22 GMT
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