Steam & Excursion > 1309 tonnage

(Please don't make this into a negative thread)

When WMSR acquired 1309 it was hoped that she would haul more without help than #734 to Frostburg.

Is she pulling doing what they hoped regarding tonnage etc?

Thanks in advance,

-Alan

Ironman Wrote:
-------------------------------------------------------
> (Please don't make this into a negative thread)
>
> When WMSR acquired 1309 it was hoped that she
> would haul more without help than #734 to
> Frostburg.
>
> Is she pulling doing what they hoped regarding
> tonnage etc?
>
> Thanks in advance,
>
> -Alan

I have not gotten up there yet; however, looking at the videos that have been posted on here and on other sites, the 1309 is pulling more passenger cars and the diesel engine for the return trip.  There is no doubt that she is pulling a much heavier train than the 734.
John in White Marsh, Maryland

I don’t know how many cars 1309 is capable of pulling out of Cumberland.

Lots of photos and videos exist online of 734 pulling nine passenger cars into Frostburg, without any diesel assistance.

With close to 100,000 lbs of 'calculated' tractive effort, on level tack
1309 could easily pull 25 to 30 passenger cars..

Grades mean physically lifting the 'weight'...so, you'd be down to 
about 15 cars on a 2% grade...in assisted.

As I remember, Western Maryland didn't have 2% grades on it's Main,
where the 1309 roams.

Remember, Tractive Effort is derived from guesses. ----  in the forms of 
math formulas, using subjective assumptions about pressures and only one
area of a single piston-face.

The actual pull generated is low at the 'standing start' since
there may only be one piston-face getting boiler pressure at the start, 
depending on the position of tte driver crankpins.
The greatest rotative-effort is at mid stroke of the piston and crankpin,
while drivers are rotating at about 12 to 15 mph.

True starting power was measured with the strain-gauge of the trailing 
dynamometer car and its instruments.   The most reliable dynamometer
measurements were conducted using two locos:  separated by the lead loco
and it's trailing dynamometer ca; then, the second loco + cars, behind.

The most useable factors were the ability to easily maintain strong pulling forces,
at the upper-end of the maximum allowable track speeds.  
The upper end of the horsepower 'curve'.  
You would want the lowest commensurate firing-rate, and highest firebox temps
with the greatest superheat temps.

You don't have superheated steam available during start-ups, or until the refractory 
brick of the firebox is actually glowing red, with incandescence..--- it takes 
15 to 20 minutes of hard drafting to get the engine THAT hot.

Power measurements would be gathered once up-to -heat' and available track-speeds allowed.
The easiest is achieved while climbing long grades, with inclines under 1%...that'll give you
the high, steady drafts and the consistent pull behind the drawbars.  That way, you can pull
the flame tips towards the hot ends if the superheater units.

The trailing-strain on flat, level track is very low, so NKP Berks, with small-ish (25") 
diameter pistons could easily haul an 80-car freight train, at speeds over 65, across the
flat plains of the Midwest--- all the while using little water & coal...

One of the reasons NKP went with smaller diameter pistons was to get longer mileage
with coal and water.
 
Excursion service, in today's world, uses more fuel and water, than hauling 
long freight trains... mostly because drafting velocities through the grates are low.

You're using the carbon fuel to 'burn' the oxygen..... the hotter the fire, the easier it is
to do that.  

The challenge for the fireman is to build a thin firebed and keep a steady 
coal-feeding rate, with comparatively low draft rates (light trains)  ...

Remember that oxygen is only about 12% of the air, by volume; nitrogen and the other
gasses ( 88%) are 'inert': thus, no help when it comes to combustion.

The engineer matches the throttle setting to limit his top, allowed track speeds.
So, you can be pulling a speedy excursion, with the throttle only open at 25%---and the
valve gear setting with a tiny opening, that closes after 15% of the power stroke!

What's doing the 'work' is the full boiler pressure at the piston valves , coupled with the
high superheat acting on the pistons.   It's the HEAT that powers the piston-stroke...
the superheat,  although losing temperature, lasts the entire stroke --- all the way to the
opening of the exhaust ring...

You can have superheat conditions out the stack... meaning that the exhaust steam
(of a superheated loco), is hotter than the commensurate temperature of the exhaust steam
of a non-superheated engine, at atmospheric pressure .... 

And, yes, if 1309 is running in compound, you can have superheated steam powering the 
LP pistons.... The steam used by the HP cylinders is still under (reduced) pressure in the
receiver pipe that feeds the LP cylinders --- and the steam in that pipe can still be
at superheated temperatures, even though at a lower pressure .... that superheated steam
will exert it's force for virtually the entire stroke, even with the valve gear shortened  at a
limited  cut-off point.

Also see N&W's Y-class, 2-8-8-2, articulated compounds ....all superheated ...

​W.

 



Edited 1 time(s). Last edit at 09/07/22 09:29 by wcamp1472.

My understanding is that the last stretch on the WMSR into Frostburg, where it laves the allignment of the old WM mainline and uses the alignment of the former C&P, is considerably more than 2%.  Any experts here know the exact grade on the C&P into Frostburg?



Edited 1 time(s). Last edit at 09/07/22 08:58 by LTCerny.

2%!

That'll make her BARK!

​W.

wcamp1472 Wrote:
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> 2%!
>
> That'll make her BARK!
>
> ​W.

I took several cab rides in 734 and you could definitely tell when the train hit the old C&P. The locomotive was definitely getting after it on the last little bit up into Frostburg.

Posted from iPhone

I believe the ruling grade on the C&P portion of the route is 2.8%. As far as what 1309 can and can’t pull, it is a moot point since all runs include a diesel anyway until the turntable situation is resolved.

Posted from iPhone

Whatever it might do it sure looks good doing it!

Out 

I do know that back in the earlier years when Dan Pluta, Mike Manwiller, and some others, were still around, the 734 could pull 11-12 cars to Frostburg unassisted, if the sanders were working. But in later years the valve timing got pretty poor and likely driver tires were worn, etc, and her rating was much less.

bmoore765 Wrote:
-------------------------------------------------------
> I believe the ruling grade on the C&P portion of
> the route is 2.8%. As far as what 1309 can and
> can’t pull, it is a moot point since all runs
> include a diesel anyway until the turntable
> situation is resolved.
>
> Posted from iPhone

Train length is also dictated by how long the passing siding is in Frostburg. Unless they decide to extend it in the future, longer trains will still have to have a diesel on the rear.