Broadway Limited T-1 4-4-4-4 (or is it a 4-8-4 ? )

Ahhh, BR19.1001! There was a V twin on each of the four driven axles. It was going to suffer from having unconnected individual axle drive.

The part above the frame was common with the class BR03.1000 series which was built with streamlining.

The loco suffered from boiler problems, if my limited German is correct, and as it was built during the war it was put aside in storage rather than being sorted. My guess as to the real problem was getting the high pressure steam pipes to the four sets of cylinders steam tight. As the boiler was identical to the series of about

70 BR03.10 locos there should have been sufficient experience to get that bit right.

As most electrics (and Diesels) were by that time being built with individual axle drive, it makes sense that steam locos should also be built that way. Why cart around all the extra unsprung weight of those huge drivers and rods?

Regards, Greg.P.

Actually, it was a 2-8-2, or is that a 2-2-2-2-2-2 ... lets not start THAT again!

Anyway, it had FOUR driver sets, each one driven by a TWO cylinder 'V' engine mounted at ONE end of the axle. The directions of the powered axles alternated, so only two engines were visible from either one side of the loco, but all drivers were powered. 2-cylinders times four axles equals eight total, so it was a 'V-8', sort of, actually four 'V-2's.

It made for a VERY strange looking locomotive. Apparently it survived the war, and was found by the US occupation forces.

Dan Mitchell ==========

PEACHCREEK wrote:

They are connected suspension wise in the same frame, but the driving forces are NOT connected. Each engine is separate. That is what is meant by a duplex. TWO engines, not connected power wise, in the same rigid frame. It is sometimes called a 'divided drive' locomotive.

There was some discussion of adding additional drive rods to connect the two engines. THEN it would have been, unambiguously, a 4-8-4 with four cylinders. Several such 4-cylinder locomotives were built, in various configurations, D&H had them (as compounds, but that's a separate story) with two cylinders forward, driving back (conventionally), and two more under the cab, driving forward. A bunch of foreign (the the USA) locomotives had four cylinders all at the front, usually two outside the frames and two inside. More cylinders made for a smoother torque flow, and a better factor of adhesion, bu the added complication just wasn't worth the slight improvement in performance. Same goes for the three cylinder locos, some of which were used in service in the USA by SP, UP, IHB, and perhaps others.

The PRR T-1s had all cylinders in conventional orientation, as did their S-1 and Q-2 duplexes. This placed the rear cylinders between the two sets of drivers, lengthening the wheelbase (which was long to start with). The odd Q-1, however, had the rear cylinders under the cab, and driving forward. This desirably shortened the rigid wheelbase, but caused other problems.

Dan Mitchell ==========

The O-Family wrote:

Yup! And the D&H's "L.F. Lorree", a big 4-8-0, was a high pressure compound to boot. Yet another bold but failed experiment.

LOTS of well intentioned people tried LOTS of things to make a better steam loco. Some of their ideas actually worked, but it was a all for a lost cause.

Dan Mitchell ==========

PEACHCREEK wrote:

Maybe, but then other locos of the period had boiler problems that were related to the use of unsuitable material and some design quirks. Not all of Wagner's ideas were successful. Do you know what the loco's working pressure was?

What's confusing about it? It was a 4-8-0.

On Thu, 12 Feb 2004 14:42:33 UTC, "Daniel A. Mitchell" wrote: 2000

Since steam cylinders are normally double acting (one of the benefits of external combustion) they would be V-4s, maybe even V-8s since they produce power on each stroke.

Not really ... it's still just a V-2, but a double acting one granted ( I assume the prototype WAS double acting ... it was a strange beast to be sure).

The number of power impulses per stroke is NOT a measure of the number of cylinders. A conventional loco has just two cylinders, but still produces four power impulses per turn, same as each 'stage' of this odd German creation.

And, a Heisler is considered a two cylinder engine, a V-2, even though it too produces four power impulses per revolution of the drive shaft (many more per driver rotation, as it's geared down).

Dan Mitchell ==========

Ernie Fisch wrote:

20 kp/cm2 DWD 1250mm Cylinders 300mm x 300mm

The BR03.10 and BR 01.10 boiler pressure was 16 kp/cm2

On comparing the boiler volumes, this loco was not a match with the BR 03.10 which was the lightweight S/L Pacific but it could have been based on the BR

01.10 heavy S/L Pacific with variations in superheating and heating dimensions.

Regards, Greg.P.