'What-If' locomotives ...

[D-Angle]

Russkies do Donk!




Yeah Boyeee...   

We be pimpin', comrades!

[jcf]

ATSF experimental concept from the late '60s - early '70s, the coaxial train.
Deck only 24" above the top of the rail, individually powered 16" modular wheel
assemblies on 4' centres. I'll post the rest of the details later.

[PR19_Kit]

INDIVIDUALLY powered, or powered as pairs?

It makes a whole lot of difference to the way such a wheelset takes curves or not.

[Dizzyfugu]

I wonder about the rotation speed of those small wheels, depending on the indented speed of this concept. Looks as if it was supposed to be rather fast? 

[jcf]

Individually powered.

I'll be scanning in all of the text later, there's a fair amount, and then run it through my old version
of Acrobat with OCR.

The info is from The Bulletin, Vol. 35 No.1 1970, National Railway Historical Society.

[PR19_Kit]

Individually powered.

Hmmm, I'm not surprised they didn't take it further.

Coned railway wheels depend on both wheels being attached to each other to curve properly. That individual powered wheel system would have needed a REALLY precise speed control system for each wheel to enable it to curve without horrendous wheel tread and flange wear, probably rail wear as well.

I'll look forward to the text, it should be very interesting.

[jcf]

The full text of the article after OCR and cleanup:

"Eighteenth century mine waggons slowly evolved into 1970's freight cars.
Like dinosaurs, these cars have become too big, too heavy and too clumsy.
But are such units the only practical way to move freight along a railroad?
Santa Fe researchers pondered this. The result of their pondering and
experimentation is a 12-flanged-wheel centipede known as the 'coaxial train',
which now exists as a 1/8-scale model in the R&D laboratory at Topeka, Kan.
It is predicated on the realization that U.S. railroads will be forced to make do
with conventional - if improved - track, and on presently existing routes.

Says Railway Age: 'The Santa Fe design had to provide:
-A lowered center of gravity,
-Minimum wind resistance,
-An alternative to standard, rigid axles, to cut down on rail and wheelwear
on curves,
-Improved weight distribution,
-Modular construction, to permit maintenance to make quick repairs/parts
replacements,
-A smoother ride, through elimination of slack action,
-Power distribution evenly throughout the train, for smooth acceleration,
-A redesigned braking system.'


The coaxial train would have a diesel powered electric generator car at the head
end, whose power would be distributed to small motors on each individual wheel
in the train. The design does not incorporate such traditional devices as brake shoes,
couplers, draft gear, slack adjusters or (in the normal sense) truck side frames and
bolsters.

Coaxial trains would be built to predetermined lengths. Each train would have one
continuous center sill, which would flex around curves and still have ample strength
to support very heavy loads. Santa Fe points out that the feasibilityof the laterally-flexible
center sill has been proved in operation of welded-rail trains, in which 1440-foot rail
strings bend around curves and create no derailment problems.

The main deck of the coaxial train would be just 24 inches above top of rail.
The designers have packed a lot of hardware into that two-foot space. First, there
are the modular wheel assemblies, using wheel approximately 16 inches in diameter.
Assemblies are spaced about four feet apart. A wheel deck, fastened to the flexible
center beam, is provided for each opposing pair of wheels. No axles are used and
each wheel has its own knee-action, enabling it to stay right with the rail, no matter
how rough or curving the track. Between the wheel deck and the main deck are plastic
cushioning tubes which run longitudinally on each side of the train. These tough,
liquid-filled tubes would effectively distribute any bump on one side to all other wheels
on that side. Above the wheel decks is the main deck. This can be varied in length, but
in a prototype, it would probably be designed to handle a 40-foot container. Support
between the wheel decks and the main deck is "provided by rollers, spaced four to
each wheel deck. The main deck is fastened to the flexible center beam at only two
points, approximately one-fourth of the deck length in from each end. This two point
fastening and the angling of the support rollers toward the two points would permit the
deck to 'float' around curves.

Top speed? ATSF says 'over 100 mph.' And braking 'would be fully dynamic, with
uniform brake application, through either electrical or hydraulic systems.' Although this
Santa Re idea is supposed to be primarily concerned with container traffic, a similiar
concept might be able to carry enormous loads of bulk traffic at high speeds and still
be easy on equipment, track and costs."


Cheers 

[PR19_Kit]

Hmm, at 100 mph those 16" wheels will be doing 2112 rpm, pretty darn fast.

And the bit that says '-An alternative to standard, rigid axles, to cut down on rail and wheelwear on curves' is just plain wrong.

Disconnected wheels like that won't steer properly on curves and would have INCREASED the wheel and rail wear, unless they had a variable speed control for each wheel that adjusted its speed appropriately to the radius of the curve.

I'm not sure if the technology required to do that existed in the early 70s. I certainly did maybe 10-15 yrs later, but not then.

[jcf]

Hmm, at 100 mph those 16" wheels will be doing 2112 rpm, pretty darn fast.

And the bit that says '-An alternative to standard, rigid axles, to cut down on rail and wheelwear on curves' is just plain wrong.

Disconnected wheels like that won't steer properly on curves and would have INCREASED the wheel and rail wear, unless they had a variable speed control for each wheel that adjusted its speed appropriately to the radius of the curve.

I'm not sure if the technology required to do that existed in the early 70s. I certainly did maybe 10-15 yrs later, but not then.

I think that was the point of each motor/wheel being independently sprung and attached to the flexible center beam:
"No axles are used and each wheel has its own knee-action, enabling it to stay right with the rail, no matter
how rough or curving the track."

It's entirely possible that things didn't work out as hoped in testing.

[PR19_Kit]

I'm sure they didn't, but it's odd that they took little notice of one of the fundamentals of wheel-on-rail technology, which was reasonably well known at the time.

My divisional boss at British Rail, Dr. Alan Wickens, did a vast amount of research into these fundamentals in the mid to late 60s and discovered new factors in the wheel-rail interaction field, and British Rail made that knowledge freely available world-wide. As a result almost every high speed railway in the world uses that technology today, with the prime exception of the Japanese Shin Kansen lines, who have much increased wheel and rail wear as a result.

[zenrat]

Rail and wheel wear:  Gives us a valid reason to use a phrase which always caused me to snigger when working for the railway, and still does - Flange Lubrication.

[PR19_Kit]

If the wheels and track are in good condition, and aligned correctly, there shouldn't be any need for flange lubricators, but sadly that's rarely the case, especially with freight lines.

[zenrat]

IME grease pots were mostly used on S&C.  Possibly also on particularly tight curves.  It's long while ago and i've forgotten a lot.

[PR19_Kit]

Our route to the Test Track went round Syston North Curve, a few miles north of Leicester, and it had a 10 mph speed limit as it was so tight.

That curve had TWO flange lubricators, one at each end, and they made a right mess of our hi-tech wheels! So much so that we always had to clean the wheels over the drop pit once we'd got to the Test Control Centre.

[NARSES2]

Rail and wheel wear:  Gives us a valid reason to use a phrase which always caused me to snigger when working for the railway, and still does - Flange Lubrication.

I now have visions of you in the background of an old black and white Carry On film doing just that