Talk:Vacuum brake

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Are vacuum brakes employed on heavy road vehicles and if not, why?Myrtone (the strict Australian wikipedian)

Use on road vehicles: Vacuum brakes were originally developed to provide a continuous brake through all the vehicles in a train. This was not necessary in a road vehicle. Furthermore, the requirement to maintain the vacuum (using the small ejector) meant a constant bleed of steam from the boiler, which would be harder to sustain in a road locomotive. It would have been simpler to use a straightforward steam brake, where a small piston acts directly on the brakes only when required. Indeed, this was the method used on "freight-only" rail locomotives intended for use on unfitted stock (i.e. waggons which carried only hand-operated brakes). Moonraker88 20:50, 15 April 2006 (UTC)

Air brakes is more fool-proof, and is not likly to suck dirt and other things into it as is the case if you have a road as compared to a rail underneat you. Also the English version of the Vacuum brake article is a joke compared to the German one i'm strongly considering translating that one to english and using it instead of the current one. And regarding steam breaks they are the prefered means of breaking a locomotive in any situation even if you do have vacuum/air-brake equipment on board.


[edit] Article Flow

I think this article needs a bit of pruning. It doesn't flow very well for an uninformed reader -- and they are the people we are writing this for. Also several non sequiturs and logical jumps, and the inclusion of slang terms reduce the authority of the writing.

Afterbrunel 06:59, 7 August 2007 (UTC)

User:Afterbrunel is right in his criticisms, and I say this as the guilty party regarding some of the colloquial terms. However, his/her removal of the step-by-step operational sequence makes the article harder to follow for the "uninformed reader" and in my view is "pruning" too far. Some valuable material has been lost here. I am considering tidying and reinstating some of it, as a standalone "Operational sequence" paragraph. WP is not a "how to" manual, so possibly the detail of actually how to use the gadget (which I thought was interesting) could stay deleted. Views? --Old Moonraker 07:12, 19 August 2007 (UTC)

Happy for your improvements to be made. Can you give me a couple of days to finalise what I am doing (in case we cut across one another's edits)?

There's still a lot to do; by the way, I deleted most of the "other railways that use vackum" paragraph because it looked a bit non-authoritative -- I was expecting someone to put "citation needed" on it at any moment.

So far as Armagh is concerned -- obviously dear to your heart -- I am happy that you have reinstated it. Could you maybe just hone the wording a bit. When I read "This happened in the Armagh accident", I look for what it was that happened in the preceding words. (I presume you know that you can get the full text of the Inquiry at http://www.railwaysarchive.co.uk/documents/BoT_Armagh1889.pdf

regards

Afterbrunel 20:16, 20 August 2007 (UTC)


Sorry, I meant to say, after "because it looked a bit non-authoritative " that if you know of any way of checking that the information is up to date, that would be a great help. Afterbrunel 20:17, 20 August 2007 (UTC)

Thanks for the greeting on my talk page.
I will certainly wait until the changes have settled. The "Armagh" edits weren't mine (but the topic should be in). I am more interested in seeing the "operational sequence" material restored, as I think that it aided understanding.
The old diagram from the 1911 Britannica was poor, but the new one is misleading as it doesn't show the ball valve: how does the vacuum reach the space above the cylinders? How does the fail-safe "vacuum reservoir" operate? I was waiting until "Handbook for steam locomotive enginemen" from the British Transport Commission (one of my sources) comes out of copyright at the end of this December to replace that image with one or two from the book, but if really pressed I could draw one for use here, showing the critical components. This would not be any time soon, as I will shortly be on wikibreak.
I cannot comment on whether the "non authoritative" terminology is still current, but as it is original research, dating from my own days of firing and driving steam locomotives, it doesn't really have a place here.
I readily concede that the article "as was" needed improvement, but this is not yet it.--Old Moonraker 05:30, 21 August 2007 (UTC)


If you have a minute before you go, why not just put a few bullet points here about what you think is missing (and would plan to add when you get back).

I'm not being defensive about the diagrams, but: I wanted them to be as simple as possible; how does the vacuum get to the top? well, as the former non-authoritative text said, by having a flap piston ring like a bicycle pump does. But this only happens once a day (when the vehicles first get coupled to a locomotive after sleeping overnight) and never again during that day's work, so (I humbly suggest) it is a complication that migth not be essential.

Everyone: there are several things this still lacks, and anyone who can help would be welcome; no doubt you can see shortcomings yourselves, but these are the ones I can see:

  • Were the Caley and the GER the only UK companies that used Westinghouse? Did they do so exclusively, or only on some passenger stock? Did they do so throughout their lifetime or only for a time? Cna we track down a source?
  • When was the simple vacuum brake first adopted on a widespread basis? Ditto for automatic vacuum?
  • Did no European railways dabble with a vacuum brake? Ever?
  • Can we track down an authoritative source on what major railways still use vacuum if any?
  • When did BR (or whatever it was then called) discontinue using the automatic vacuum brake?
  • Can we add some more detail about freight use of the vacuum?

That will do for now.

Afterbrunel 17:10, 21 August 2007 (UTC)