If you register, you can do a lot more. And become an active part of our growing community. You'll have access to hidden forums, and enjoy the ability of replying and starting conversations.

Condensing apparatus on steam locomotives.

Discussion in 'Steam Traction' started by Matt35027, Jan 26, 2013.

  1. Matt35027

    Matt35027 Well-Known Member

    Joined:
    Oct 16, 2009
    Messages:
    1,122
    Likes Received:
    143
    Gender:
    Male
    Occupation:
    Builder
    Location:
    Near 74D
    Heritage Railway Volunteer:
    No I do not currently volunteer
    I was thinking while watching footage of the LU150 steam specials (of course, early underground engines had condensing gear, which sparked this thought in my head) could locos operating on the mainline, where water capacity is a major constraint, be kitted out with condensing apparatus to save water?

    Bit of a whimsy, but could it be done? Would it be effective enough to make it worthwhile?
     
  2. Jamessquared

    Jamessquared Nat Pres stalwart

    Joined:
    Mar 8, 2008
    Messages:
    26,105
    Likes Received:
    57,435
    Location:
    LBSC 215
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    I think the significant problem (apart from all the extra plumbing) is that the feedwater would gradually heat up, eventually getting to near boiling point. At that point, the injectors (which rely on cold water to condense a jet of steam) no longer work. So you can't get water in.

    If you look at most 19th century locos that had feedwater heating and / or condensing gear, they also had something other than injectors to get the water into the boiler: either steam driven donkey pumps (favoured by Beattie, amongst others: take a look at an early photo of a Beattie well tank) or crosshead driven feed pumps (favoured by Stroudley, amongst other). Donkey pumps have the advantage that you can run them even when the loco is stationary, but mechanically they are another system on the loco that needs building and maintaining, with moving parts that need lubricating, valves that need maintaining etc. Crosshead pumps tend to be simpler, but only work when moving - if you needed to put water in the boiler while stopped in a station, you needed to find a convenient siding to run up and down, or, in extremis, slip the loco on greased rails.

    You then have two secondary problems. Firstly, the condensed steam is contaminated with oil, which either has to be separated out, or else enters the boiler as a contaminant and can cause problems such as excessive priming.

    Secondly, the hot water can cause degradation of the paint on the water tanks (and could also scold a passenger inadvertantly leaning against the tank or tender). If you look at a Stroudley loco such as Terrier, they have an inner tank, surrounded by an outer sheet with a small gap between, so that the hot water in the proper tank is insulated from the outside of the loco. Billinton continued that pattern of tanks even though his engines didn't have condensing gear: call it conservative drawing office practice.

    I suspect it would be a non-starter on the modern railway, certainly to retrofit to an existing loco.

    Tom
     
    domeyhead likes this.
  3. RalphW

    RalphW Nat Pres stalwart Staff Member Administrator Friend

    Joined:
    Sep 11, 2005
    Messages:
    35,446
    Likes Received:
    9,144
    Gender:
    Male
    Occupation:
    Retired-ish, Part time rail tour steward.
    Location:
    Northwich
    Heritage Railway Volunteer:
    No I do not currently volunteer
  4. QLDriver

    QLDriver New Member

    Joined:
    Apr 3, 2011
    Messages:
    81
    Likes Received:
    40
    Gender:
    Male
    Occupation:
    Materials Testing
    Location:
    California, USA (From Yorkshire)
    Heritage Railway Volunteer:
    No I do not currently volunteer
  5. ADB968008

    ADB968008 Guest

    There's a condenser tender from a BR52 in Neuenmarkt-Wirsberg germany.. just no loco to go with it
     
    Sir Nigel Gresley likes this.
  6. John Webb

    John Webb Member

    Joined:
    Mar 2, 2010
    Messages:
    501
    Likes Received:
    86
    Occupation:
    Retired
    Location:
    St Albans, Herts
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    The other problem is that the steam, if directed into the tanks to condense, is not exhausting up the chimney to draw air through the fire in proportion to the working of the loco. So there had to be a compromise between using the condensing facility and switching to normal exhaust whenever possible to keep the fire going.

    Besides LT engines, some LNER locos, particularly Class N2 0-6-2T, were fitted with condensing apparatus for use over the Metropolitan "Widened Lines" to work to Moorgate. These were in use up to the 1960s.
     
    Simon4576 likes this.
  7. huochemi

    huochemi Part of the furniture

    Joined:
    May 6, 2008
    Messages:
    2,751
    Likes Received:
    1,393
    Gender:
    Male
    Location:
    UK
    Heritage Railway Volunteer:
    No I do not currently volunteer
  8. marshall5

    marshall5 Well-Known Member

    Joined:
    Oct 26, 2010
    Messages:
    2,377
    Likes Received:
    3,981
    Location:
    i.o.m
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    As were the 97xx panniers and some ex LMS 3F tanks eg 47202. Ray.
     
  9. Jamessquared

    Jamessquared Nat Pres stalwart

    Joined:
    Mar 8, 2008
    Messages:
    26,105
    Likes Received:
    57,435
    Location:
    LBSC 215
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Another problem with the Stroudley variant was that sharp stops caused oily mucky water to surge back through the condensing pipes into the smokebox, where it would be ejected through the chimney upon starting, to the detriment of the locomotive's paint finish and the clothes of any nearby passenger. A sharp clout with a heavy hammer by the driver on the end of the copper condensing pipes generally worked wonders on the future cleanliness of the engine and passengers, but didn't do much for the future ability to condense steam...

    Tom
     
  10. RalphW

    RalphW Nat Pres stalwart Staff Member Administrator Friend

    Joined:
    Sep 11, 2005
    Messages:
    35,446
    Likes Received:
    9,144
    Gender:
    Male
    Occupation:
    Retired-ish, Part time rail tour steward.
    Location:
    Northwich
    Heritage Railway Volunteer:
    No I do not currently volunteer
  11. std tank

    std tank Part of the furniture

    Joined:
    Sep 20, 2005
    Messages:
    3,808
    Likes Received:
    946
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Liverpool
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Also add the Fowler 2-6-2 tanks based at Cricklewood and Kentish Town and the Mersey Railway locos, such as Cecil Raikes.
     
  12. Jimc

    Jimc Part of the furniture

    Joined:
    Sep 8, 2005
    Messages:
    4,052
    Likes Received:
    4,665
    Occupation:
    Once computers, now part time writer I suppose.
    Location:
    SE England
    Heritage Railway Volunteer:
    No I do not currently volunteer
    One of the more interesting must have been the Dean Goods fitted with Pannier Tanks and Condensing gear for wartime service. Reading the piece about managing the condensing system linked above makes me thing that one set of tanks must have been reserved for the hot water.
     
  13. Jamessquared

    Jamessquared Nat Pres stalwart

    Joined:
    Mar 8, 2008
    Messages:
    26,105
    Likes Received:
    57,435
    Location:
    LBSC 215
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Does the preserved LNER N2 still have working condensing gear, or is it cosmetic only these days? (I assume cosmetic, but would be nice to know).

    Tom
     
  14. brit70000

    brit70000 Member

    Joined:
    Jul 7, 2007
    Messages:
    274
    Likes Received:
    30
    It's cosmetic only. Other than the external pipes which are blanked off there is no condesing equipment fitted.
     
  15. John Stewart

    John Stewart Part of the furniture

    Joined:
    Sep 22, 2011
    Messages:
    4,206
    Likes Received:
    2,072
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Hilton, Derby
    Heritage Railway Volunteer:
    No I do not currently volunteer
    In Britain there was never any shortage of water so condensing was only ever used for locomotives on underground railways to try to limit the emission of smoke and steam. Therefore it was only on tank locomotives where there was no room for cooling and the water in the tanks did warm up, but not to an impossible extent as the underground sections, where condensing was next to compulsory, were not too long. In South Africa, condensing was used on tender locomotives to conserve water in desert regions. There was room for cooling equipment which, whilst not producing cold water, could keep its temperature down to workable limits.

    As John Webb says, there is bound to be a deleterious impact on steaming. Whilst the opposite of condensing, the Franco-Crosti boilers remain a dreadful lesson in the perils of interfering with the proven way of working boilers.
     
  16. ADB968008

    ADB968008 Guest

    The German BR 52 could cover several hundred miles between water stops... but also had thousands of screws to separate engine from Tender... (in order to turn them)...however they were kind of built to only go one way... East...
     
  17. sowerbylad

    sowerbylad Guest

    Was an awesome sight Ralph. Saw this run at the Kimberley Steam Festival in July 1991.
    Will have to get round to getting the video off u-matic onto the pc and YouTube.
    Regards, John.
     
  18. andrewtoplis

    andrewtoplis Well-Known Member

    Joined:
    Mar 28, 2006
    Messages:
    1,357
    Likes Received:
    816
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    The Metropolitan and the District Railways both had locomotives fitted with condensing apparatus, but I believe this was to do with reducing the volume of smoke and steam exhausted rather than saving water. I know that the Met. had a series of troughs into which the locomotives would dump their condensing water when they were being serviced. Where this waste water ended up is not recorded - presumably it found its way into the Thames! Secondly, the Met condensing locos had a lever for the driver to close or open the condensing feed - presumably when the came out on the Hammersmith branch they would shut the condensing off and run as a normal locomotive. This is still present on number 23 in the London Transport Museum.

    Fenchurch also has dummy condensing pipes fitted.
     
  19. Thompson1706

    Thompson1706 Part of the furniture

    Joined:
    Nov 19, 2007
    Messages:
    2,438
    Likes Received:
    1,844
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Rhiwabon
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    The Mersey Railway locos also dumped water & re-filled their tanks at the end of each journey. Mersey no. 5 'Cecil Raikes' still has its condensing gear despite 50 years of industrial service.

    Bob.
     
  20. Jamessquared

    Jamessquared Nat Pres stalwart

    Joined:
    Mar 8, 2008
    Messages:
    26,105
    Likes Received:
    57,435
    Location:
    LBSC 215
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    I guess that mode of working you get the primary advantage of reducing condensation in tunnels, but by trapping the condensate in a separate tank that is not part of the main water feed system, you avoid the disadvantages of lubricating oil carry over into the boiler.

    Tom
     

Share This Page