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(erielack) questions about Erie steam locomotives



  Niether one was an "Assembled "  truck.  Both were a
cast bed frame truck, but were signifigantly
different.

 The "LIMA Articulated Trailing Truck " was a patented
,set up, developed and built ONLY by Lima Locomotive
Works initially for the original 63" driverwed Berks
and later the T&P 2-10-4's with the Erie Berks being
the last locomotive to recieve this truck. 

  When Lima developed a firebox big enough to need a 4
wheel trailing truck they also wanted to not have to
pay any licensing to General Steel Castings and the
owner of the patent rights on the "Delta " style truck
. They also developed the "split frame articulation
bed as purely a way not to have to pay patent rights.
The idea was the frame ended right after the rear
driver with a pocket / pin assembly for the trailing
truck to insert into like a draw bar. Hard pinned in
and with little allowance for vertical movement, the
trailing truck was to act in conjunction with the main
frame as an articulated frame to the draw bar buffer
assembly connection to the tender. 

   Lima's problem with this was that the system was
developed for the small "mikado" sized berks and 
worked reasonably well for the T&P texans but when you
got to the Erie Berks the sheer size was out of the
range of this systems capabilities. The reason being
that the boiler is fix mounted to the frame, on every
locomotive, only at the cylinder saddle and all heat
expansion of the boiler is thrust rearward and
supported by the waist / firebox  bearers (big sliding
blocks in channels). The boiler is not attached to
anything but the cylinder saddle and just rests on
frame and at full temp / pressure is about 7 1/2
inches longer than it's assembly / unpressurized /
cool  size. 

  With that said on a normal locomotive ,fire box
bearers move horizontally rearward on the frame and
the frame moves side to side on the rear rockers of
the pivoting trailing truck. That trailing truck
floats freely and only supports weight and acts as a
guide in curves.  Where as the Lima Truck they carry
weight and handle two directions of movement and as a
frame extension. Also Without a frame to hold the ash
pan the lima truck had one mounted to the truck and it
had to be considerably larger to account for the
lateral movement of the truck.

The biggest problem with that truck was ( from AMC
documents) the tendancy of the truck to wanting to
"clothesline" from the weight of the train and force
of forward movement and "jacking"  in reverse. This
clothes lining caused extreme excesive wear on the
lateral of the engine and trailing truck in the hub
liners and bearing boxes ( in fact there is special
retrofitting done on the driving boxes to add
additional support to the ears to keep them from
breaking off), and excesive chewing on all flanges due
to the wheel base size.

Shortly after these berks were in service drawbar
horsepower tests were done by with CB&Q's Dyno car and
it was determined there was vertually no difference in
draw bar horsepower ratings between the two systems. I
have never found out who initiated the tests but no
other Locomotives were ever built with that system
again after the last order Erie engines.


As a note to definitions:

An assembled frame has two styles for a locomotive.

A full riveted bar frame. Consisting of bent or
straight bar riveted ridigly together to form the full
frame , later welded 
 
or

two cast  complete side frames ( left and right ) with
cast or bar cross members rivetted or welded together
. 

Erie berks were the latter and did not have full cast
intergal frames like the NKP or other Van berks.

In trailing trucks the closest thing to assembled
would be a cole or hodges trailing truck 

 Also, There is very little thrust bending on a cast
side frame locomotive as drive thrust is all in line
with the frame and the direction of movement and
crossmembers are larger and welded in place. 

Quote:

"over 75 % of frame repairs are cracks resulting in
stress from vertical movement working a joint or pin
location , caused by unballanced wheels( pounding) or
poor track conditions. The remaining 25% is a direct
result from incedent trama."

(Railway mechanical Age magazine)

Also there is NO additional weight placed or thrust on
the rear trailing truck. 

With fully equallized spring rigging set up the way it
is if there was weight added to the trailing truck it
was weight taken off the main drivers. Which they
would not have done. They would not have cared about
the TF they would have gained on a device only usable
up to a speed of around 20 MPH.  Overall weight on
drivers was determined by the structures Dpt. and
bridge loading capabilities. And dispersed in equal
proportions to all drivers and truck axles.  Vertical
clothes lining that would add downward thrust onto a
trailing truck is elimiated between the tender and
Locomotive through the use of the radial buffer and
drawbar. This is done specifically to eliminate
jacking due to slack action from the train.  The only
TF added is the additional weight of the franklin  c-2
booster unit ( 2250 pounds not including the axle
mounted gear)

Believe me because in the last year I have been
involved in redrawbarring three mainline locomotives ,
retramming two and rewheeling two, removed the booster
and trailing truck wheel sets from one. 


The main reason for the abandonment of this truck was
that the excessive wear and maintenance by the
railroads was cost prohibative. And if Lima was going
to lose orders due to that they were going to pay the
money to general steel castings. As a side note CB&Q
2-10-4s were built by Baldwin even though Lima's Cost
Quote was less.

Rich Young






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