Steam Cylinder Cocks

[atsfsteam]

How important are the steam cylinder cocks on live steam engines. Are they just for show or they really important.
I have seen some engines where they do not work and they a are still operated.
Just wondering.

[cbrew]

very important,
one can get away with out using any on slide valve engines because it is possible to raise the slide valve but it is still not wise and can get messy,
on piston valve engines, risking damage due to hydro lock.

need someplace for the water to go.

[atsfsteam]

Thank you.
I know what hydrostatic lock can do to gas and diesel engines and it is not good.
I just could not figure out why they still operated the locomotive with the steam cylinder cocks not working.

[littleevan99]

Like cbrew said, they're really important. When I've ran my CliShay the few times I have, the cylinder cocks shoot water out a few feet at first then a mist until the cylinders have warmed up.

[Kimball McGinley]

Getting away with something is not the same as doing the correct thing. A practical answer may involve the size of the loco and cylinders, how robust they are, how hot the steam is, boiler pressure etc. and how much risk one is willing to take, in addition to slide vs. piston valves.

[Marty_Knox]

I can tell you stories about their use on full size locomotives. We blew out a cylinder head on our Ten-Wheeler at the Huckleberry RR when the engineer didn't open them - the wheels didn't even make one full revolution.
I was firing 1225 from Cadillac back to Owosso. We had a Canadian 'Guest' Engineer running the photo runby at Lake George. When he went to back up he didn't open them - I yelled over "cylinder cocks!" We had to wait a while for the go ahead, again he didn't open them. I yelled over "cylinder cocks!" again. He said "You Americans have a fetish for cylinder cocks!" My reply was "We've been working water all the way down from Cadillac! Now open the blank-blank cylinder cocks!"
Oh, and they are operated by air on a full size locomotive.

[Harlock]

It is a huge issue on full size engines, live steam locomotives can typically take the brunt of a water hammer. The only major side effect is getting a shower of oily water.

I hate wet steam so I use mine liberally, especially when starting out for the day. The cylinders take a while to completely warm up so the engine tends to run wet for a half a lap.

-M

[Erie2936]

A lot of good posts on the importance of cylinder drains on a steam locomotive. I would like to add that having a drain that can open automatically when hydraulic pressure becomes too great when in the closed position is a nice feature to have as well. There are quite a few steam operated cylinder drains on the market and I believe most will open momentarily to let a slug of water out. Mechanically operated drains however are usually not so forgiving.

Below is a link to a video of my Okadee style cylinder drains in operation.

https://www.youtube.com/watch?v=CT-JTWHuScc



Okadee Cylinder Drain Operation

Regards,
Brian

[DianneB]

I believe most will open momentarily to let a slug of water out. Mechanically operated drains however are usually not so forgiving.

I have seen a design for manual cylinder cocks that use a ball, a spring, and the activating lever is a ramp that tightens up on the spring - they will open automatically if there is enough water. "One day" (which is sort of like "A Round To It") I would like to build a set of those for my American.

I have steam-operated drains right now and they work great. Sometimes I am out on the track, well away from the station, and one or more drains will "sneeze" and blow a little water - NICE feature! - but they are either open or closed and I would like to be able to 'feather' them when starting off (which I would be able to do with mechanicals).

[NP317]

I believe most will open momentarily to let a slug of water out. Mechanically operated drains however are usually not so forgiving.

[snip]

I have steam-operated drains right now and they work great. Sometimes I am out on the track, well away from the station, and one or more drains will "sneeze" and blow a little water - NICE feature! - but they are either open or closed and I would like to be able to 'feather' them when starting off (which I would be able to do with mechanicals).

My full-sized steam locomotive experience had the cylinder cocks either fully open of fully closed. No "feathering.
That defeats their purpose.
I see no reason to do otherwise with our miniature locos.
~RN

[steamin10]

Some one has plans for mini drains that are self opening. They squirt the water out and seal up when under steam. Any time they load up with water they will jet it out and reseal. Any body know where those drawings were, Kozo perhaps?

[DFB]

Dave, I'm not sure, but I believe that is what's on my little engines 0-6-0. I'll get a picture of them later on. Basically theres just a small steel ball inside. No springs or other control. I have not steamed the loco yet but hopefully will soon.
Dale