Steam & Excursion > 4014 Superheater type

Reading the literature, the first batch of Big Boy's were equipped with Type E superheaters, and supposedly, the last deliveries were Type A due to servicing simplicity.
As 4014's tube sheets were rebuilt, it seems there was an opportunity to choose either superheater type. 
Which superheater type does 4014 now contain?

Apologize if this was already discussed.
Thanks,
...bill

Illbay Wrote:
-------------------------------------------------------
> Reading the literature, the first batch of Big
> Boy's were equipped with Type E superheaters, and
> supposedly, the last deliveries were Type A due to
> servicing simplicity.
> As 4014's tube sheets were rebuilt, it seems there
> was an opportunity to choose either superheater
> type. 
> Which superheater type does 4014 now contain?
>
> Apologize if this was already discussed.
> Thanks,
> ...bill

Simply changing the flues/tubes or the tube sheets, hasn't anything to do with superheater type. The key component requiring a change from Type E to Type A, would be the superheater/throttle header housing.

Thanks for that info. That makes sense.
I suspect this means 4014 retains its original Type E design?
...bill

Prior to the 4014 leaving SoCal I was told by a fairly reliable source that the plan was to convert the Type E superheaters to Type A. Whether or not that happened, I can't speak to.

Chico43 Wrote:
-------------------------------------------------------
> Prior to the 4014 leaving SoCal I was told by a
> fairly reliable source that the plan was to
> convert the Type E superheaters to Type A. Whether
> or not that happened, I can't speak to.
I have heard the same thing locally so that can be a winter project for Ed and the boys.

Bob Krieger
Cheyenne, WY

Bob3985 Wrote:
-------------------------------------------------------
> Chico43 Wrote:
> --------------------------------------------------
> -----
> > Prior to the 4014 leaving SoCal I was told by a
> > fairly reliable source that the plan was to
> > convert the Type E superheaters to Type A.
> Whether
> > or not that happened, I can't speak to.
> I have heard the same thing locally so that can be
> a winter project for Ed and the boys.

And just where do they propose to "borrow" a complete front-end throttle/superheater header for such a huge job. Not to mention spending all that money on the existing set-up, only to tear it all out for scrap?

Another 2 million bucks and as Jack says, a minor parts availability issue.

Out

I suppose you could say that when you have a bank account the size of the Union Pacific's, nothing is impossible.

Chico43 Wrote:
-------------------------------------------------------
> I suppose you could say that when you have a bank
> account the size of the Union Pacific's, nothing
> is impossible.

Except,,,,,,,,,,money is NOT the only factor in this. Where would they "obtain" the proper throttle/superheater header assembly which would fit a 4000 class locomotive. If my memory serves, the ONLY one would be inside the front end of #4023, currently on display overlooking Interstate 80, in Omaha, NE. Maybe there are others?

Chico43 Wrote:
-------------------------------------------------------
> Prior to the 4014 leaving SoCal I was told by a
> fairly reliable source that the plan was to
> convert the Type E superheaters to Type A. Whether
> or not that happened, I can't speak to.

Doesn't this mean the conversion was considered before the rebuild? Therefore, the decision has been mande, and whatever is in there now is what will  say there.
...bill

Illbay Wrote:
-------------------------------------------------------
> Chico43 Wrote:
> --------------------------------------------------
> -----
> > Prior to the 4014 leaving SoCal I was told by a
> > fairly reliable source that the plan was to
> > convert the Type E superheaters to Type A.
> Whether
> > or not that happened, I can't speak to.
>
> Doesn't this mean the conversion was considered
> before the rebuild?

Only rumors.

Therefore, the decision has
> been mande, and whatever is in there now is what
> will  say there.

Right.

> ...bill

That would require removing all the tubes and making new tube sheets along with a new header. A hell of a lot of work. The Type A has a number of 5-1/2" inch flues where the Type E are small.  The tube sheets would have to be made new, new braces and a ton of other work.  It is doable, but not practical and I don't understand why they would want to do it. 
Of course my opinion and a dollar will get you a coffee at McDonald's.

And the price of the retrofit would buy you a McDonalds.

Out

HotWater Wrote:
-------------------------------------------------------
> Chico43 Wrote:
> --------------------------------------------------
> -----
> > I suppose you could say that when you have a
> bank
> > account the size of the Union Pacific's,
> nothing
> > is impossible.
>
> Except,,,,,,,,,,money is NOT the only factor in
> this. Where would they "obtain" the proper
> throttle/superheater header assembly which would
> fit a 4000 class locomotive. If my memory serves,
> the ONLY one would be inside the front end of
> #4023, currently on display overlooking Interstate
> 80, in Omaha, NE. Maybe there are others?

Jack (or Don, Wes, etc)... what are the differences between Type A and Type E, why would one be better than the other for an excursion engine? What would the benefit be?

Edit: I know this has been discussed before just can't find the thread

Regards,

Dave



Edited 1 time(s). Last edit at 07/19/19 23:20 by dbesade.

I’ll take a stab at it...

The distinction has to do with the number of “return bends”, nearest the firebox ends,

Type A units fold the superheater tubing into passes inside a single 5 1/2” flue.  The flues are arranged in a rectangular pattern in the flue sheets.  The front flue sheet is a larger diameter sheet than the rear tube sheet.  The rear tube sheet is the front wall of the four-sided furnace.  On a coal burner the flloor is made of cast iron plates, cast with air holes throughout ( there are also types made of smaller, cast iron “fingers” slid onto the rows of grate bars to make a flat array for the the grates).

The rear tube sheet’s size is much smaller than the the front flue sheet since it must fit inside the the boiler....
So,  Type A superheater flues ( the 5 1/2” flues) are squeezed-down, by the manufacturers, down to about 3 1/2” diameters.
The ‘necked-down’  ends are formed in a swedge-Ing press, that evenly compresses the rear operations of the tubes for a length
of 18” to 24”..  The swaged ends are fitted tinto the rear tube sheet in the same rectangular array as the front flue sheet, only squeezed together in a tighter pattern.

Type E superheater units ( ‘ units’ are the tubes that carry the steam to the cylinders, Superheater flues are the boiler’s fire-tubes that  the ‘units’  fit into) are formed into four separate, one-trip, passes, through one of four smaller flues.  A single Tyoe E unit, occupies 4 adjacent flues, to form a four-pass bundle.  The bundle actually splits the steam flow into two streams, each sending the steam into the ‘hot’ end two times —- to superheat the steam.  The two streams are merged into one tube at the front of the boiler & mounted into the ‘superheater header’ casting.

The modern superheater header also includes a steam flow regulating valve ( throttle) consisting of sequentially opened 
disk-like,  smaller valves.  A cam shaft with lobes mounted in a spiral fashion, lifts & holds each valve open, sequentially, as the engineer pulls the throttle handle wider and wider ‘open’.   Engines built earlier than the mid-1930s, typically had a single valve throttle mounted in the steam dome, with the steam pipe ( dry-pipe) leading through the steam spaces do throght the front flue sheet, to the cast iron, superheater header in the smokebox.   The entire, successful desugn was perfected in the late 1800s in Germany by an inventor named Schmidt...thus the Schmidt Superheater became the workable design...
Other various attempts were made..all of which ere problematic..  

Oil burners typically have a single burner, mounted very low down at the front of the firebox and aimed at the rear sheet of the firebox ( the door sheet).  The burner typically drools the oil flow onto a ‘fan-like’ braid steam jet thacarrues the oil, breaks it up into droplets and burns it in mid-air —- as the terrific wind through the firebox carries the flames into the rear flue sheet, over the superheater units , and out the stack.

Oil burners’ floor of the firebox is the firepan, below the flame and firms a tub mounted to the rectangular base of the furnace
( the “mud ring”) .... this sheet-steel tub is covered in several, neatly built layers of refractory brick that completely lines and protects the the steel firepan.  The refractory brick is vital to the steam generating capacity of the firebox —— only coming into play when it has been heated to a hot, red, incandescence by the intensity of burner flame —- fanned by the drafting air-flow regulated by air openings anddampers that durectthe combustion air through the furnace.  Under low draft conditions, like sitting around, long  down-grades of the right-of-way, etc., the incandescence of the firepan subsides, and and the firebox temperatures cool-off...
the cooler furnace leads to the propensity to make dense clouds of solid black carbon of unburned fuel—- drifting across the landscape...

Now, back the the hot flames of a thundering, modern steamer, pulling a decent staring of cars, loaded to about 80%  of the engine’s pulling capacity... all producing a white-hot, 3,000 deg. fire-tornado inside the furnace.  The burning tornado is sucked into the flues ... at a very high velocity ...   

(My essay is getting too large for T.O., and the typing is more problematic...so I’ll start a continuation ...in part 2...)...

W.

not spell checked, yet...



Edited 2 time(s). Last edit at 07/20/19 13:10 by wcamp1472.

Part 2...

Now, let’s pull the pieces together, and get into superheating...

Superheating of steam only occurs when the furnace flames are sucked, deep into the fire-tubes if the boiler.  
So, sitting around, drifting with a partially closed throttle, low speeds and a very light load behind the tender ... all low draft conditions will not make superheating possible... 

Steam DOES NOT absorb heat, as water does.  Steam is a gas of water...it’s molecules (2H2O) are vibrating, separated and bangening into each other .... the steam is at the same temperature as the boiling water ( near 400 deg. F) ....as soon as the steam flow leaves the boiler ...flowing to the cylinders ( flowing towards lower pressure) it begins to cool down—- the lower the pressure, the cooler the steam... soon water molecules combine —forming water droplets, becoming water vapor.  Clouds in the sky are condensed water —- floating in the air....and weighing millions of pounds....recent  rain storms drooping 4 to 5 inches of water per hour,  are tremendously heavy... 

In locomotives, most of their time, under steam, is spent in the saturated state.  The saturated state refers to the heat content of the steam...Remember when boiling, the steam is at the temperature as the water... water at 400 deg can make steam at 400 degrees.
HOWEVER... IT  takes 8-times the quantity of heat to convert water into steam —- at the same temperature, as it took just to get to that boiling temperature.

 if it takes 1,000 BTUs to get ( a small quantity) of the confined water to boil, it takes 8,000 BTUs to make steam, at the same temp...Thus the steam is “saturated” with heat.  Heat saturation has nothing to do with the ‘wetness’ of the steam, only its capacity to maintain its gaseous state.  If the pressure drops,  temperature also drops,—- then a certain amount of the steam compndenses back to a visible sroteam cloud...technically a vapor cloud..

If you redirect the steam flow into a pipe, away from the boiling water, you can heat the pipe-up, which will excite the battering molecules  to greater states vibration....the increasing heat separates the molecules further and further apart.... Now the
temperature is increased, but the pressure remains the same....
The trip through the units results in fewer ( more exited) molecules  exiting the units than enters the Units ....
( lower mass, greater heat..at the cylinders —- which is why operating at superheat temps are more ‘efficient’, when superheating)

We talk about the degree of superheat as being the number of degrees above the nominal 400-deg if the boiling water.
Thus, water at 400 degrees, can be superheated to, say, 750 deg.  
So,  the amount of superheat is 350 deg, added to the nominal 400 deg...

With a heavy load behind the tender, the draft will be strong—- pulling a lot of air theitgh the firebox...If you match the fuel
feed-rate to the air flow ....you can get up to 3000 deg from a carbon fuel..( All Carbon must be turned into a gas before it can be oxidized in a flame...so, it does not matter if  the source is coal or oil...).

With a heavy train, it takes time to get the firebox’s refractory bricks to get to incandesce....Oncevthe bricks get to glowing, you can expect the the whole machine to begin to “heat-up”...  Soon you’re pulling the 3000 degree flame tips into the superheater flues and boiler tubes...

Here’s the problem: the boiling water, at 400 degrees, is 2600 degrees COLDER than the ( 3,000 deg.) flame tips.
The boiler flues and tubes are submerged in the the ‘cold water’.....

After entering the flues and tubes, the gas stream is broken into very small steams inside each flue and tube.
 After about 18” to 24” inches, our hot gasses are cooled down to 400 degs of the surrounding boiler water.
So, how much of the superheater is actually adding superheat to the steam flow?

Answer: only the short distance, at the ( back end) return bends, gets to add significant heat to the steam flow..  

( more cantankerous behavior in the word processor...)

Part 3 coming-up...
still not proofed, yet..



Edited 1 time(s). Last edit at 07/20/19 07:00 by wcamp1472.

Part 3...

Why Type E units came into being...

Type A units are made of one tube, folded 4 times.... thus, there are two “ Hot Ends” for each unit.
If you increase the numbers of Hot Ends, you can increae the the amount of superheat ( over the small er Type A units)
....in the steam flow.

Type E units each have 4 Hot Ends exposed to the flames....thus, Type E units have DOUBLE the number of “beneficial return bends” to generate superheated steam...

So, let’s summarize:  

The amount of superheat depends on the heat of the fire,  the heat of the fire depends on the weight of the train ( NOT the weight of the engine, or the engineer) , AND the grade of the track ( uphill or downhill)..

The draft is produced by, and dependent on, the weight being hauled.  There is also the amount if time that the load is dragging on the engine...so, in gently rolling countryside, your superheat temperatures is gonna vary all over the needle... on a 60-mile grade, like the Continental Divide, your gonna be “in strongest superheat”, pretty much  all day....

Across a fleet of locos, or across TWO fleets of locos, one fleet: Type E equipped &  one fleet: Type A equipped....
Type E’s are  more subject to repairs and down-time, compared to Type A units. ( Also, in today’s world it’s harder to get all the water with compressed air, as in winter-preps, when in outside storage..)

The  fleet of Type E unit locos will spend more time in the shops for superheater maintenance, than the locos equipped
with Type A units.*

With a single specimen to consider upgrading?
I’d stick with with Tyoe A units .....
4014 ain’t ever gonna see glory days again....it’ll be more of a “freak show”, than a working Iron Horse...

Remember, the amount of superheat is only deoendent on the weight behind the tender....with 12, or so cars & 1 dynamic braking unit—- you’ll NEVER get to 700 degrees of superheated steam, ( nor, will you ever get to a 3000 deg. fire in the firebox)
with the current operating modes of 4014...

Only way to get there is with a decent “stack train”, like 3985 got to romp with .... long ago and far away..
Even then,  3985 wasn’t heavily taxed...

Thanks for hanging-in there...
See?  It’s the “simple questions”  that are the hardest ...

Next, we’ll get into ‘radial’ valve gears..

W.

(* NKP Boilermaker, Joe Karal, had a method to repair the split ends of Type E Units, from inside the firebox, without removing the affected unit... 5 minutes and DONE... versus a couple of hours..)
(still not proofed, yet)
 



Edited 2 time(s). Last edit at 07/21/19 08:41 by wcamp1472.

Thanks Wes for another great explanation. Better not tell Ed that all of that train is not taxing the load on the 4014. We want a 120 car freight run.....

Yes... Agreed. ..a goodly numer of cars would be impressive.

I’ll bet that the films of the engines, shot in the 50’s,  shows immense trains being hauled by the 4000’s.

I’d better buy a couple ( DVDs?) ..got any favorites to recommend?

​W.

 

wcamp1472 Wrote:
-------------------------------------------------------
> Yes... Agreed. ..a goodly numer of cars would be
> impressive.
>
> I’ll bet that the films of the engines, shot in
> the 50’s,  shows immense trains being hauled by
> the 4000’s.
>
> I’d better buy a couple ( DVDs?) ..got any
> favorites to recommend?
>
> ​W.

If I remember correctly, Pentrex purchased the rights to the Union Pacific "company film/films" titled "BIG BOY". I'm pretty sure that the Union Pacific Historical Society offers/sells DVDs of that series.