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Mallet Restoration in Brazil
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Author:  softwerkslex [ Sun May 07, 2017 11:28 am ]
Post subject:  Re: Mallet Restoration in Brazil

I can't tell. What do you think? I see steam supply to back unit, exhaust from front unit. But the rest?

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Author:  J3a-614 [ Sun May 07, 2017 12:52 pm ]
Post subject:  Re: Mallet Restoration in Brazil

The locomotive is a simple 2-6-6-2; the key is that the cylinders are the same size. If it were a compound, the front cylinders would be larger to account for lower steam pressure.

The engine's plumbing looks to be similar to that of a number of simple engines, including the C&O Allegheny. Steam flows to the rear cylinders, where it is divided, with half going to the rear cylinders and half back to the front cylinders in a pipe that runs between the frames of the front engine. This layout features only a single ball joint above the articulated connection that has to handle high pressure steam. Despite its location, it's an easier maintenance burden for high pressure steam than the multiple hinged and sliding joints of something like the N&W A 2-6-6-4.

The exhaust steam, which is of very low pressure, is much easier to handle in the combination of hinged and sliding joints from the front engine to the exhaust stand.

On this engine you can also see the exhaust pipe from the rear engine; this is just inside the piston valve, and runs behind the live steam pipe to the exhaust stand.

Author:  MargaretSPfan [ Sun May 07, 2017 2:47 pm ]
Post subject:  Re: Mallet Restoration in Brazil

J3a-614 --
Thanks for the correction!! My bad.....

Still a great engine! I mean, how many articulated steam locomotives are actually operational these days? Worldwide, I think you can count them on the fingers of one hand -- with fingers left over. Folks -- please correct me if I am wrong.

Author:  Alexander D. Mitchell IV [ Sun May 07, 2017 5:37 pm ]
Post subject:  Re: Mallet Restoration in Brazil

Technically the Double Fairlies of the Ffestiniog Railway in Wales (three operational, one being built anew), the prototype Beyer-Garratt K1 (at Ffestiniog), and the numerous Beyer-Garratts of Africa in Cape gauge and two-foot gauge (including several of the latter at the Welsh Highland) are all articulated steamers.......

.... so you're up to several hands and feet already.......

Author:  MargaretSPfan [ Sun May 07, 2017 6:13 pm ]
Post subject:  Re: Mallet Restoration in Brazil

LOL, Alex! Forgot about the Beyer-Garratts and the double Fairlies!

Author:  hullmat991 [ Sun May 07, 2017 9:45 pm ]
Post subject:  Re: Mallet Restoration in Brazil

MargaretSPfan wrote:
J3a-614 --
Thanks for the correction!! My bad.....

Still a great engine! I mean, how many articulated steam locomotives are actually operational these days? Worldwide, I think you can count them on the fingers of one hand -- with fingers left over. Folks -- please correct me if I am wrong.

I know of two 2-6-6-2T's that are operational and two more that are in the process of being restored back to operational status. Not to mention a certain C&O that will hopefully be operating in a year or less; that makes for a full hand's worth of fingers and we haven't even talked about the Big Boy or the international articulates.

Author:  J3a-614 [ Sun May 07, 2017 10:45 pm ]
Post subject:  Re: Mallet Restoration in Brazil

Oh my, how do you define articulated engines?

Well, working from memory, Lionel Weiner, who wrote the book "Articulated Locomotives," catalogued a huge number of types.

As I recall, they came in several variations, including semi-articulated engines (Mallets and their simple brethren, in which only one engine set was free to move relative to the boiler and main frame), fully articulated engines (Beyer-Garratts, Kitson-Meyers, Fairlies, and geared engines such as Shays, in which all driver sets could move relative to the boiler and main frame), and temporarily articulated engines (a rod engine with a booster would fit this category).

Some engines, notably some German machines, had outside frames with cranks that looked like a rigid 0-8-0 or 0-10-0, but the cranks turned what I would describe as a shaft that ran inside a hollow axle, with a type of ball joint that allowed the axle and its wheels to take up a radial position to the rails, even though the shaft remained stationary relative to the frame.

http://www.douglas-self.com/MUSEUM/LOCO ... indner.htm

Source of the link above:

http://www.douglas-self.com/MUSEUM/LOCO ... coloco.htm

Weiner's full list of classifications, as he used them:

True Articulated Locomotives
1. Articulated Locomotives having one driven and one undriven bogie - eg single Fairlies (Mason Bogies)
2. Articulated Locomotives with one engine and two driven bogies - eg geared locomotives such as Shay, Climax, Heisler
3. Articulated Locomotives with two engines and two two sets of driving wheels - eg double Fairlies, Meyers, Garratts

Semi-articulated Locomotives

1. Semi-articulated Locomotives with a single engine and two driven trucks eg Klien-Lindner axle locomotives
2. Semi-articulated Locomotives with two engines and two sets of driving wheels eg Mallets

Temporarily Articulated Locomotives or Locomotives with Auxiliary Engines
1. Booster Engines

Utilisation of the tender's weight for propulsion
1. No Engine to the Tender eg modified Engerths, St├╝tz tender locomotives
2. Steam Tenders

Wow, that's getting to quite a list. . .and now I've got to dig out my copy of Weiner's book.

Author:  softwerkslex [ Mon May 08, 2017 5:02 am ]
Post subject:  Re: Mallet Restoration in Brazil

Don't forget the Baldwin flexi-beam. It must have had enormous rod klank.

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Author:  dinwitty [ Mon May 08, 2017 12:08 pm ]
Post subject:  Re: Mallet Restoration in Brazil

The throttle mechanism must be underneath the boiler with a steam pipe from the dome above borrowed thru the bottom of the engine boiler to the throttle.
I see the exhaust pipe on top of the cylinders while the inputs are in front on the inside

Author:  dinwitty [ Mon May 08, 2017 12:18 pm ]
Post subject:  Re: Mallet Restoration in Brazil

Earl Knoob wrote:
Looks and sounds to be a simple articulated, not a "true" Mallet. But, the Espee called all their cab forwards "Malleys", whether simple or compound.


Mallet does not define if the engine is simple or compund, it is only another definition of an articulation engine, "Mallet" is the name of the person whose name is coined on the definition of an articulation engine.

https://en.wikipedia.org/wiki/Mallet_locomotive

Author:  Dennis Storzek [ Mon May 08, 2017 1:35 pm ]
Post subject:  Re: Mallet Restoration in Brazil

I beg to differ. From the text of the same source, "The essence of his idea combines articulation of the locomotive and compound steam use."

Therefore, to be a Mallet, the locomotive must:

1. be articulated
2. be compound

Or it is not a Mallet.

Author:  WVNorthern [ Tue May 09, 2017 10:02 am ]
Post subject:  Re: Mallet Restoration in Brazil

Weren't some Mallets capable of being run in both simple or compound mode?

Author:  Dennis Storzek [ Tue May 09, 2017 10:37 am ]
Post subject:  Re: Mallet Restoration in Brazil

Yes, but only for starting, when there is no low pressure exhaust stem to power the low pressure cylinders. To try to run the engine continuously was a simple machine just wastes the efficiency they were trying to attain by using the steam twice, and the larger low pressure cylinders aren't optimized for high pressure steam, IIRC, engines equipped with starting valves had a pressure regulator to reduce the pressure of the steam fed to the low pressure cylinders.

Author:  PaulWWoodring [ Tue May 09, 2017 4:38 pm ]
Post subject:  Re: Mallet Restoration in Brazil

MargaretSPfan wrote:
J3a-614 --
Thanks for the correction!! My bad.....

Still a great engine! I mean, how many articulated steam locomotives are actually operational these days? Worldwide, I think you can count them on the fingers of one hand -- with fingers left over. Folks -- please correct me if I am wrong.


If they are still in service, there are two 0-4-4-0T compounds on the Harz Mountain Ry. in Germany, both I believe late 1890's vintage.

Author:  perudale [ Tue May 09, 2017 8:10 pm ]
Post subject:  Re: Mallet Restoration in Brazil

No one has mentioned that this is a meter gauge locomotive and that it had to travel a fur piece from Southern Brazil to its new home in Central Brazil. Also when I was in Brazil on a charter tour in 2002 we stopped outside the main shops to see a line of dumped locomotives along the mainline of the Dona Theresa where one of it's sister 2-6-6-2 was rusting in the deadline. Also another is plinthed in the home of the shops which I can't recall how to spell it. So as of 2002 all three articulated locos were still intact. Also the shops had a deadline of over a dozen 2-10-4s out of service due to boiler failures that were withdrawn in the 70's. The excursion train in the video is on a active freight railroad that is dieselized.

Dale Brown

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