Water in loco steam brake and ejector systems

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John M
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Joined: Fri Oct 23, 2015 7:01 pm

Water in loco steam brake and ejector systems

Post by John M »

If my Allen mogul could talk, it would scream "Quit water-boarding me, I ain't no terrorist!"

On air, both the loco brakes and ejector work fine....of course! However, on steam, quite a different matter.

After application, lap and release the trapped water in the loco steam brake cylinders and lines prevent the shoes from releasing completely, and drag for some time. Even additional external springs don't help much. What to do?

My Nelson-designed vacuum ejector (18" hg at 80 psi) seems to entrain water enroute to the tender. Another what to do?

Any articles in Modeltec or Live Steam magazines address this matter?
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Fred_V
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Re: Water in loco steam brake and ejector systems

Post by Fred_V »

I think, typically, with a steam brake you need to drill a small hole at the lowest point in the cyl. It will blow steam while the brakes are applied but will allow water to get out on release.

The vacuum system shouldn't get water in it since the ejector is drawing a vacuum. I've been running vac. brakes for 20 years and have never had a problem with water. Maybe look at how the ejector is mounted as on release the diaphrams will draw air back in. If there is condensate at the ejector it could be drawn into the piping.
Fred V
Pensacola, Fl.
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cbrew
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Joined: Sat Jan 04, 2003 12:17 pm
Location: Vancouver Wa

Re: Water in loco steam brake and ejector systems

Post by cbrew »

John M wrote:If my Allen mogul could talk, it would scream "Quit water-boarding me, I ain't no terrorist!"

On air, both the loco brakes and ejector work fine....of course! However, on steam, quite a different matter.

After application, lap and release the trapped water in the loco steam brake cylinders and lines prevent the shoes from releasing completely, and drag for some time. Even additional external springs don't help much. What to do?

My Nelson-designed vacuum ejector (18" hg at 80 psi) seems to entrain water enroute to the tender. Another what to do?

Any articles in Modeltec or Live Steam magazines address this matter?
are you just using a steam valve to control the brakes,
when i was still running vacuum, my ejector would run full time and i used a three way valve to control the brakes.
zero chance of drawing water into the vacuum line at that point
If it is not live steam. its not worth it.
little giant
Posts: 187
Joined: Tue Jan 06, 2015 5:35 pm
Location: Rochester NY

Re: Water in loco steam brake and ejector systems

Post by little giant »

If you are getting water in your vacuum lines or cylinder, you should make an inline reservoir to capture the water so you can drain it at the end of the day. This reservoir will keep the water from getting into the vacuum cylinder and ruining the diaphragm.
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Fender
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Location: Chattanooga TN

Re: Water in loco steam brake and ejector systems

Post by Fender »

Another suggestion on the vacuum brakes: put a check valve between the ejector and the vacuum cylinder(s). A Clippard MCV-1 check valve would be suitable. Then use a separate valve to open the vacuum line to release the brakes. This will keep any condensate in the ejector from being drawn back into the system when the steam is turned off. If the vacuum system is tight, you should be able to retain braking action even after the steam is turned off to the ejector.
Dan Watson
Chattanooga, TN
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John_S
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Location: Cumming, GA

Re: Water in loco steam brake and ejector systems

Post by John_S »

Fred_V wrote:I think, typically, with a steam brake you need to drill a small hole at the lowest point in the cyl. It will blow steam while the brakes are applied but will allow water to get out on release.
This is EXACTLY what I missed on my Allen mogul when building the brake system and had the same problem as John M is speaking of. There's a 1/16" hole that needs to be drilled in the atmosphere side of the brake cylinders. This allows condensate to drain out.
Steamin
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Location: St. Louis, MO, USA
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Re: Water in loco steam brake and ejector systems

Post by Steamin »

little giant wrote:If you are getting water in your vacuum lines or cylinder, you should make an inline reservoir to capture the water so you can drain it at the end of the day. This reservoir will keep the water from getting into the vacuum cylinder and ruining the diaphragm.
I added a steam/water separator inline with the steam line to the locomotive brake cylinder, with success. I used an 'automatic drain' in place of a manual drain valve.

It was a simple fabrication.
http://www.neidrauer.com/HeavyMikado/Se ... _4396.html
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