Was the UP Challenger a 100 % substitute for the UP 9000 class as concerns t.e.??

[Juniatha]

Hi Erik

 

Off hands - I guess film boiling should be possible - you only have to have the 'right' combination of heat impact per unit of area , low water circulation speed plus 'sufficiently' low boiler pressure .   If this should happen it would quickly raise mean wall temperature at that area which would be highly destructive of course .   I have wondered more than once about L D Porta's obviously nonchalant approach to firebox heat loads in his super-performing boilers being a back-bone of his light-weight super-output engine concepts made posible with highly efficient draughting , I don't know where and how much if so he accounts for ageing of steel in general and boiler / firebox steel especially under repeating in and out plastic deformation stress .   The classic Stephensonian boiler concept can only be pushed so far until things get out of hands - already the most lively steaming of locomotive boilers were much better performing than stationary boilers of power plants as concerns quotient of mass unit of water evaporated per hour by mass unit of construction material  .  

Regards

Juniatha

 

 

"Making a flame for the photographers"

- a feat that in the 1970s DB steam fans liked to ask steam crews of oil-fired engines for ;  some aquired considerable skills in producing a spectacular effect while others tried and never got much above a plume of smoke .  

In his painting a friend who has spent lots of miles on oil-fired engines widens on history by having a firewoman make a flame in his own design of a late era Atlantik type locomotive.

( with permission by painter for posting in this forum only )

[Firelock76]

Juniatha

Hi Firelock

>> Oh yeah, except there's no Maalox, Alka-Seltzer, Bromo-Seltzer, Brioschi, Gas-X, ...<<

.. or Coca Cola .  

 

 

... only :  why is she holding that Art Nouveau Tiffany glass mobile phone ?

I mean , no doubt we liked chattering back then , Coke or not ...

 

= J =

Hi Juniatha!  Well you know, back those days Coca-Cola DID have cocaine int it.  Maybe she just THINKS it's a mobile phone!  "I get no kick from cocaine, mere alchohol doesn't thrill me at all...."

[Firelock76]

And wow, that painting of the flaming firebox is something else!  Gives a new spin on the term "Hot Blonde"!

[erikem]

Juniatha

"Making a flame for the photographers"

- a feat that in the 1970s DB steam fans liked to ask steam crews of oil-fired engines for ;  some aquired considerable skills in producing a spectacular effect while others tried and never got much above a plume of smoke .  

In his painting a friend who has spent lots of miles on oil-fired engines widens on history by having a firewoman make a flame in his own design of a late era Atlantik type locomotive.

( with permission by painter for posting in this forum only )

Nice..

Some later steamers had overfire openings in the side of the firebox, but my recollections was those were only used on coal burning engines. On an oil burner, those openings probably could spout some serious flame with appropriate manipulation of the firing valve - i.e. shutting it off, then turning it full on.

My only close encounters with an oil burning steamer has been with Ventura County #2 at OERM in Perris.

Film boiling was one of the issues covered in my thermal-hydraulics classes, since the heat production from a fuel rod didn't depend too greatly on that specific rod's temperature, assuming the nearby rods were immersed in water (moderator). In a firebox, the local temperature rise due to film boiling would reduce the radiant or convective heat transfer and possibly drop that low enough to re-establish nucleate boiling. If the firebox wall is hot enough to support film boiling, it is probably weakened enough to be in danger of not supporting full boiler pressure.

- Erik

[GP40-2]

feltonhill

Sorry to be so late with this.  Out of town the past four days.

The video "The Phoenix Engine" covers 614 on B&O and according to both the liner notes and actually counting cars, 614 took 11 cars plus A-tank up 17-mile grade (Hopewell estimate of 1,200 tons) and 22 cars + a-tank up Sand Patch (no estimate of tonnage).  A quick calculation indicates that if 17-mile is 2.6%, 22 cars+a-tank (maybe 1,800 tons??) would have a grade resistance alone over 110,000 lbs, well over 614's total low speed TE of 66,450 lbs engine or 78,850 lbs with booster.  Drawbar pull would be about 3,000 lbs less at 10-15 mph.  This doesn't include curve resistance which can be significant (as you can hear on the YouTube clip).  If this is 17-mile grade (2.6%) , 614 isn't t pulling 24-cars.

'Regardless of the numbers, 614 shows amazing tenacity the whole time, particularly on one of the curves, holding the rail at what must be absolutely full throttle while speed drops to what, below 10 mph?  In the pacing vids you can see 614 swinging from side to side under the piston thrust.  Simply an amazing performance while doing a job for which it wasn't designed.

feltonhill,

You are right, it wasn't 24 cars on the 17 Mile Grade. That was a typo on my part that I didn't even notice until you posted this. I meant to type 14 cars (13 passenger cars + the A tender). That's what I remember the train length being on that trip, but that was 30 years ago, so it very well may have been 11 cars + the A tender for a total of 12 behind the 614.

However, there were multiple trips over Sand Patch, both from Cumberland and Pittsburgh with trains of varying lengths. The shortest was 16 cars + the A tender, the longest was 24 cars + the A tender. With the longest train, the 614 was down to below 10 mph in sections. We calculated that the 614 was putting out between 83,000 lbs and 84,000lbs TE (with booster) with the 24 car + A tender train on Sand Patch.

You are right about the tenacity of the 614 on a hard pull. I really don't remember the 614 slipping once on either the 17 Mile or Sand Patch. The one B&O Grade that got the 614 was when Ross tried to pull 24 cars + A tender up the nasty Streets Run Grade on the W&P Sub out of the Monongahela River Valley in Pittsburgh. Again, no slipping, the 614 simply ran out of pull about 1 mile short of the Whitehall Tunnel.

I suspect the Mechanical Engineers from Lima would be rolling over in their graves if they knew what Ross put the 614 through during these excursions and the ACE tests.

[Juniatha]

Hi -

 

Whatever the number of coaches – it sure was brave work !   Yet , all these ‘gym’ work out type of low speed max pull ramp exploits do read somewhat strange to me .  

     Ok , these locomotives were solidly built if any locomotive ever was .  They took up with really hard work and stood up to it .   Yet , if I were to have a locomotive ( luckily PKP bureaucracy saved me from my headless attack of attempting to buy one 42 class Decapod shelved in what appeared decently good condition ) and were to make excursion trips , I’d probably get a lot of ‘boos’ for keeping it at a rather leisurely trundling pace on fairly easy throttle and cut-off at decently swift yet not too hasty speed with a concise consist behind tender on rather level track following – for example – a lovely river valley , with a pusher diesel waiting at the bottom of the only ramp in a day’s trip - *ggg* .

Alas , I was not the only one to think along such lines : 

     When in the summer of 1987 , to join the 150 years celebration of Austrian railways , the newly and completely overhauled Goelsdorf  310.23 four cylinder compound 2-6-4 made its initial trip from Knittelfeld workshop in a mountain valley to Austria’s capital city , Vienna , the trip included travelling the Semmering pass .   With his vintage electric coupled to the back end of the train before attacking the long climb , intending to be a good colleague the ‘electric driver’ really pushed the train up the winding curves of the steep grades – so much so to have front buffers of front car pressed to tender buffers – leaving no more than its engine unit for the venerable compound to lift up the pass , still with impressive enough plumes of white steam puffing up from narrow stack .  It was only later when on one of the many day trip tours offered during these wonderful weeks of steam # 310.23 came to stretching legs a bit when the compound definitely rose above average Strauss waltz tempo heading a vintage consist at some 65 mph with perfectly smooth running and whispering exhaust .  

But that’s another story …

Regards
            Juniatha

[Lehigh Valley 2089]

Don't know, but railroads got engines as needed, and the 9000 series was bought when the Compound Mallets were on the mainlines. When the problems came up with the 9000s with cornering, that is when the challengers came to the UP, followed by the 3900 class, and the 4000 series Big Boys.

So, I don't think that the 4-12-2s were abandoned when the challengers came, but were stored and used as needed.

As far as rigid verses articulated, the articulateds won hands down, granted that the Texas types were really close with t.e. The articulateds win because t.e. goes up w/ weight by nature, and the nonrigid engines had 4 cylinders instead of 2 or 3.

Also, 2-10-4s weren't as flexible as A classes or challengers or Y6bs.