Steam & Excursion > Follow the Flag...

Pending completion of a successful ultrasound inspection on one of the last two remaining Wabash steam locomotives, a path to restoration has emerged...

More details soon.

https://fortwaynerailroad.org/wabash-no-534/

 

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A “soaker”,  with Stephenson Valve gear & piston valves ...
So, how do you change the valve gear (levers) to handle the inside admission piston valves?

Change the valve rod operating lever by 180 deg. at each end?

​W.

That restoration of this locomotive to opeartion is underway makes me so happy.

wcamp1472 Wrote:
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> A “soaker”,  with Stephenson Valve gear &
> piston valves ...
> So, how do you change the valve gear (levers) to
> handle the inside admission piston valves?
>
> Change the valve rod operating lever by 180 deg.
> at each end?
>
> ​W.

What do you mean by "soaker", Wes?

A soaker is a Saturated Steam, non-SuperHeated locomotive.

James R.(Jim) Baker
Whittier, CA

Actually, a non-superheated switcher is not a such a bad idea.

Superheaters on switchers is, in reality, a superfluous accessory.   Most of a switcher’s day was spent sitting still, or shuffling a couple of cars around, then wait.

Superheaters are only effective when a firebed is fully involved and long flame tips are drawn into the flues so that the hot gasses heat up the ends of the units ....to get a loco up to superheating effectiveness can take upwards of 20 minutes of steady, strong drafting.  

Another factor in suoerheated steamer is the firebrick arch, supported on arch tubes reaching from the throat sheet backwards towards the door-sheet.   The brick arch has to get heated-up in the fire —— to near incandescence before the superheaters see enough heat to become effective at raising the steam to higher temps, above heat-saturation.   Again, it takes steady, hard beating to get the brick arch up to those kind of temperatures.   Yard switchers  would be out of town, at those sustained speeds and pounding.  For switchers, a few heavy chugs is about as hot as they get, like in kicking a few cars... 

Most switchers never see that kind of demand, so in reality even superheater-equipped swithcers virtually never see operations reaching to the superheat stage, anyhow... They’re all virtual soakers in actual daily service.

​W.

 



Edited 2 time(s). Last edit at 01/10/19 01:50 by wcamp1472.

Ok Wes I knew the answer, Super Heated, but you supplied the rest of the story and darn it, I learned something again. Your point about switch engines is logical and would explain why I recall few so equiped. In your detailed outline what it takes to make the super heater effective you mentioned it was necessary to "heat up the ends of the units". Now I don't profess to understand all I know, but I had a question. By "ends" I assume you mean the cast return bend that the super heater tubes are installed in. My question is kind of thermal in nature, does the "end" act as a form of "heat sink" to transfer thermal energy to those tubes, and if so is the "end" made of a special material? Oh, and can you explain it without getting too far off in the weeds? I'll try to follow along, Thanks for all the knowledge you share. 

Very good. I had put the term “ends” in to see if anybody picked up on that key.
You get Extra Credit.

You are very close.

Back in the day, Elesco ( Locomotive Superheater Company ) manufactured their units with ‘formed ends’, they somehow made the 180deg. return bends for a tube, with extra heavy ‘lobes’ at the firebox ends to combat severe cinder cutting or erosion of
them in a premature fashion , compared to the life of the units.

It is common for today’s practice to use cast ends, welded-on.  When there was high demand for lots of units, Elesco’s fabricating technique made sense. In today’s low consumption market of theses devices, the cast & weld process seems more economical.
Also, today’s welding processes are far superior to those of the 1930s...

What happens in the boiler is that the flames and hot combustion gasses rapidly cool down within a short distance after entering the gas tubes and flues near the firebox end.  The highest firebox  and flame temperatures are in the 3,000 deg range ( some hotter than 3,000 and some lower)..the water temps in a 250 PSI boiler are around 400 deg. F.  That’s a tremendous temperature differential, towards cold side.  Even the vigorous boiling of the water at the crown sheet is the same 400deg, temperature and is the temp steam: 400 deg.  The steam at 400 deg is said to be “heat-saturated”....as long a the steam and water are in the same container, they will both be at 400 deg. ( in actuality, water in that boiler is at many temps and below the 400 degs F , especially at the lower sections of the boiler. Heat convection currents are responsible to distribute the heat more evenly, but there is always cold water in the belly of the beast.

The superheater is a series of pipes that separate the steam from the water.  ( in the firebox, a hotter fire does NOT  make water hotter than the setting of the safety valves—- hotter fires only make more steam, at that same temperature, I.e. 400 Deg F.).
The superheaters lead the heat-saturated steam into the path of the hottest flame temperatures.  Steam does NOT conduct heat the same way that water absorbs heat...leading to making of steam ...

In the units,  the hot steel tubes ( at the firebox ends) works to excite the molecules of gas-state of water into more rapid states of vibratory activity.  The heated particles greater vibratory activity, and greater temperatures, separate the molecules a greater distance.  The greater physical ( vibratory) bouncing and molecular collisions elevate the steam temperatures ABOVE the the temps of heat saturated steam...typically that temp rise is in the range if 300 degrees.  We call that the “degree of superheat”, or 300 deg superheat.  However, the 300 deg. superheat is additive to the 400 degrees of the boiler steam, so..going to the cylinders ...you get 700 degree steam..superheated steam @ 700 degs...But that’s NOT 700 degrees of superheat...

As you can see MORE quantity steam ( at higher temps) leaves the units, than enters the units😃🔥🔥🔥
Its also possible that exhausted steam up the stack can still be superheated, but at lower temps, because it is expanded.

When a loco is running at superheated states, it consumes less water, burns less coal and is superior in performance of ‘soaker’ locos.

The. Firebox gasses...
The boiler’s tubes break the hot firebox gasses into hundreds of slender gas streams. These ( 3000 deg.) streams typically cool down to the surrounding “cold water” ( 400 deg) temps of the surrounding tubes...the hottest gasses are cooled-down in 12” to 18” after leaving the firebox.  Thus, the steam inside the superheater units only “sees” beneficial heating at the ends nearest the firebox. It’s still plenty cool —— so that you don’t need special alloy steel for the units, you need mild steel that can heat up rapidly, and conduct the heat effectively.

Tyoe A units have two return bends, at the “hot end”.
Elesco devised the Tyoe E units with a single return bend in each unit... So, the Type E units occupy 4 flues, of about 3” diameter, per unit, but there are 4 hot-end bends per UNIT..

TYPE E  units produce hotter suoerheated steam than A units, but across a fleet if locos, the Type A units hold up better, over time, than Tyoe E units.  But those differences disappear in today’s excursion world. There is NO realizable benefit to changing the type of units that your restored engine was built with.  If built with Type E units, keep them, if built with Type A units, keep them!
If upgrading a soaker to a suoerheated engine, then choose Type A units...

Thanks for hanging in there..

W.

not edited or corrected, yet...

the greater danger to units is the danger of standing-water in the units being subject to freeze damage...
more so, in type E units, but freeze-up is still a danger to A Type units... most of the freeze-ups occurs at the rear return bends.





 



Edited 10 time(s). Last edit at 01/10/19 15:37 by wcamp1472.

Okay Thanks Wes I understand it better now, even through the typos. So superheater length was not so much to give length along which to be heated but rather to reach back to the hottest fire. And the mass of the ends was for heating but also to protect from erosion. And that steam locomotives are still wondrous machines. Let's hope the little Wabash switcher has a successful restoration and a long pampered life.



Edited 1 time(s). Last edit at 01/10/19 16:13 by MP4093.

Sorry about the typos..

​But you get 100 for the basics of superheating....

Its sort of like grasping how airplane wings 'work'...its a dynamic ... meaning it must be moving to produce the effects.
​You cant get a plane to fly purely through reason or logic..it requires the physics of rapid movement for wings to work.

​Another factor is that its best if superheated locos are balanced for their load..decent amount of coaches for passenger Pacifics and Hudsons, haul the right amount of freight for Berks, Mountains, Northerns and Challengers...Balance the load to the design of the firebox, superheaters , etc.

​Use double heading, when necessary.

W.

Kelly:

Did the Wabash Railroad Historical Society ever kick in some funds for the 534 or is that in the works? I haven't heard anything since I recommended they contact you. Of course, I too am looking forward to seeing it in operation not only because it is a Wabash loco but also that it was a local engine.  And according to what my research shows, it was the last Wabash steam loco in operation as Lake Erie & Fort Wayne No. 1. There was another B-7 that operated in a gravel pit in Illinois, rather late, but not at late as No. 1.

Victor A. Baird
http://www.erstwhilepublications.com

You can contact me off the list if you like.



Edited 3 time(s). Last edit at 01/13/19 18:50 by wabash2800.

nathansixchime Wrote:
-------------------------------------------------------
> Pending completion of a successful ultrasound
> inspection on one of the last two remaining Wabash
> steam locomotives, a path to restoration has
> emerged...
>
> More details soon.
>
> https://fortwaynerailroad.org/wabash-no-534/

Great news Kelly!! The “Official Heat Treater” (can I say “official”??? - Ha!!) for everything FWRHS is ready, able and willing to assist as needed. Looking forward to providing some quench & temper and/or case hardening “on the house”!!

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