Steam & Excursion > A U.P. 4-10-4 ???

I was reading in a book called history of Union Pacific steam from the UPHS and ran into a proposed 4-10-4 Lincoln type locomotive. Not much information was given other than the FEF was chosen instead. Does anyone know if any other road tested this theory of power?

Santa Fe had very successful 2-10-4s with 74" drivers, while SP had 4-10-2s...so 10 coupled power wasn't really unusual, and UP itself had 4-12-2 engines which were powerful beasts. I suppose it's possible that they considered a 4-10-4 as a stretched 4-8-4, I would assume this would have been a freight engine, not a high speed passenger engine.

Posted from iPhone

When I look at how the firebox is over the rear drivers on a 4000 I sometimes wonder how a 10-coupled design would be, like, say a 2-10-10-2, with somewhat smaller drivers instead of the 68" they had, something that probably should have been done anyway.

As I recall I saw somewhere where the ATSF tried a 2-10-10-2 but was not for long and it was dismantled. I never heard why it wasn't successful but alas it went away.

Bob Krieger
Cheyenne, WY

I think it was because it was a compound with HUGE low pressure cylinders, and it was so out of balance that it could only really go about 15 mph. Even in helper service that's going to be quite a restriction.

Posted from iPhone

Yeah, but they were those crazy jointed boiler Mallets. (Technically only the rear being a boiler with the front being a superheater, reheater, and feedwater heater.) Virginian also had some of that wheel arrangement, also Mallets.

I was thinking more along the lines of a faster engine, sort of a doubled 2-10-4.

The problem with this type of locomotive is the size of the driving rods. The boiler would have probably generated 7000 HP and the main crank pin would be a monster. Pennsy faced this with its duplex drive engines. The size of the reciprocating rods was reduced and the Q-2 4-4-6-4 were awesome locomotives with 8000 HP. They pulled monster trains in the west, but unfortunately were massive water consumers.

Speaking of that Santa Fe Mallet, here's a mega huge resolution file of what it looked like:

http://upload.wikimedia.org/wikipedia/commons/a/ac/Detroit_Publishing_-_New_Mallet_articulated_compound_engine_on_the_Santa_Fe.jpg

Pump

The Pennsylvania Railroad's class Q2 comprised one prototype and twenty-five production duplex steam locomotives of 4-4-6-4 wheel arrangement.[1][2][3]

They were the largest non-articulated locomotives ever built and the most powerful locomotives ever static tested, producing 7,987 cylinder horsepower (5,956 kW) on the PRR's static test plant. They were by far the most successful duplex type. The duplex propensity to slip was combated by an automatic slip control mechanism that reduced power to the slipping unit.

The Q2 locomotive was 78% more powerful than the locomotives that PRR had in service at the time, and the company claimed the Q2 could pull 125 freight cars at a speed of 50 mph. [4]

Despite overall success, the Q2s were all out of service by 1951. With dieselization, they were the obvious first targets to be withdrawn since they were only a little more capable than the conventional J1 class 2-10-4s but with far higher operating and maintenance costs.

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Didn't the PRR also have 4-10-4 locomotives with 2 cylinders up front and 2 more at the rear of the 5 axles, with #3 drivers connected to each end differently on each side?

bankshotone Wrote:
-------------------------------------------------------
> I was reading in a book called history of Union
> Pacific steam from the UPHS and ran into a
> proposed 4-10-4 Lincoln type locomotive. Not much
> information was given other than the FEF was
> chosen instead. Does anyone know if any other road
> tested this theory of power?

The Lincoln under consideration was to be a 3-cylinder with 73-inch drivers and 240-psi boiler pressure. Based on a statement published in Union Pacific Magazine in August 1924 a large 3-cylinder locomotive was under consideration as passenger power! The Lincoln Type drawing was dated August 1, 1927, so clearly it was just not a passing thought, since it took three years to put it in image form.



Edited 1 time(s). Last edit at 01/21/15 13:07 by GMUP.

CPRR Wrote:
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> They were by far the most successful duplex type...
>
> The Q2 locomotive was 78% more powerful than the
> locomotives that PRR had in service at the time...
>
> ...they were the obvious first targets to be withdrawn
> since they were only a little more capable than the
> conventional J1 class 2-10-4s.

S'plain? How were they only a little more capable then
the J1's if they were also 78% more powerful?

/Mitch

CPRR mentioned the PRR 4-4-6-4 Q2. Recall, also PRR's Q1, a 4-6-4-4.

http://en.wikipedia.org/wiki/PRR_Q1

On a side note - fun to dream:

Monon 4-10-4 (Proposed by Baldwin)
http://www.railarchive.net/fantasysteam/monon_800_rcl.htm

http://www.railarchive.net/fantasysteam/


And, who knew? Central Pacific 2-10-0 built way back in 1893!
(...and scrapped in 1894):

http://en.wikipedia.org/wiki/4-10-0#mediaviewer/File:El_Gobernador_locomotive.jpg

/Mitch



PS - just for giggles:
The AA20-1, a 4-14-4, was built by the Soviet Union.

http://en.wikipedia.org/wiki/4-14-4#mediaviewer/File:Andreev.jpg

Per Wiki:
Unlike the successful Union Pacific locomotives, however, the
AA20-1 was a complete disaster. The AA20-1 made a publicity
trip to Moscow in 1935. It was then put into storage at the
Shcherbinka test facility and finally scrapped in 1960, though
this was not stated publicly.

Mgoldman Wrote:
-------------------------------------------------------
> CPRR Wrote:
> --------------------------------------------------
> -----
> > They were by far the most successful duplex
> type...
> >
> > The Q2 locomotive was 78% more powerful than
> the
> > locomotives that PRR had in service at the
> time...
> >
> > ...they were the obvious first targets to be
> withdrawn
> > since they were only a little more capable than
> the
> > conventional J1 class 2-10-4s.
>
> S'plain? How were they only a little more capable
> then
> the J1's if they were also 78% more powerful?
>
> /Mitch

Do not know.....Mongo only pawn....in game of life. Ask the Wikipedia folks.

How do all of these supersized steam locos compare to the Garratt's of Europe?

Far bigger, way more powerful.

So the Q2 was "far more powerful" than other Pennsy engines, yet only slightly more capable than a Pennsy 2-10-4??? Only good for speedy trains?

Finderskeepers Wrote:
-------------------------------------------------------
> Santa Fe had very successful 2-10-4s with 74"
> drivers, while SP had 4-10-2s...so 10 coupled
> power wasn't really unusual, and UP itself had
> 4-12-2 engines which were powerful beasts. I
> suppose it's possible that they considered a
> 4-10-4 as a stretched 4-8-4, I would assume this
> would have been a freight engine, not a high speed
> passenger engine.
>
> Posted from iPhone


Somewhere I had recently read where the UP had borrowed a ATSF 2-10-4 for testing. Anyone have any more information on that?

Here is a picture of what I am referring to.

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The ATSF 2-10-10-2 were built in 1911 from 2-10-2 locomotives.

http://en.wikipedia.org/wiki/2-10-10-2