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Pop Safety Valve and Wooden Deck Question

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Pop Safety Valve and Wooden Deck Question
Posted by ryzormachine on Wednesday, October 2, 2013 5:24 PM

Hey everyone. I have a question about Union Pacific 3985. I am curious if anyone knows if UP modified her pop safety valve from two domes to one? If so, what was the purpose and does anyone think they will make the same modification to 4014? I also have a question about when UP removed all the wooden tender decks on their locomotives?

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Posted by Semper Vaporo on Thursday, October 3, 2013 11:57 AM

Don't know what you mean by "two domes to one".  The 3985 has only one "steam dome" (the other two raised "domes" are containers for sand, to sand the rails for traction).

I also believe that all steam locomotives are required to have at least 2 safety valves, both capable by themselves of releasing more steam than the firebox is capable of producing.  (A redundant safety factor.)

 

What do you mean by "tender decks on their locomotives"... tenders are separate from locomotives.  Do you mean "cab decks/floors" or the "floor of the tender"?

 

Semper Vaporo

Pkgs.

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Posted by West Coast S on Thursday, October 3, 2013 12:56 PM

I suspect the OP is inquiring about the wooden walkways some UP tenders were equipped with, i've seen photos from the forties of  these on some four thousands and FEF's, all were coal fired. Can't say when they were removed. 

 

Dave

SP the way it was in S scale
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Posted by ryzormachine on Thursday, October 3, 2013 4:09 PM

Yes, I am inquiring about the wooden deck on the actual tender. If some one could answer when and why they were removed? Also I am not inquiring about the sand domes. I am inquiring about the one or two small domes closest to the cab of the locomotive. I hope I am giving them the proper name of pop safety valves. The Challenger 3977 looks as if it has two and the 3985 looks as if it has only one? Curious if this was a modification made by UP? Here is a photo with the arrow pointed to what I am inquiring about. Thanks!photo.php?fbid=664608293563571&set=gm.642305482456962&type=1&theater

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Posted by BigJim on Thursday, October 3, 2013 6:19 PM

That is a cover for the steam "TURRET", which is a manifold that directs steam to different steam powered accessories one being the injector, etc.

In the picture you provided, directly behind the first sand dome is the steam dome, the safety valves, the second sand dome and the turret cover.

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