Bridge girder on three PRR FM flat cars
Brian Rochon
http://lists.railfan.net/erielackphoto.cgi?erielack-12-21-19/X5845.jpg
From EL photo archive today.
Brian Rochon
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Claus Schlund \(HGM\)
Hi Brian and List Members,
Thanks Brian for calling our attention to
this.
I find it interesting that the bridge girder is NOT
mounted on the exact center of the trio of PRR class FM flat cars, and the
bridge girder is instead somewhat closer to the camera. This does two
things that I find somewhat puzzling...
(1) It imbalances the load on the trucks on the two
flats at the ends - for each of these two cars, one truck will be carrying more
load than the other truck
(2) It required the brake wheel on the flat
closest to the camera to be removed. Had the load been placed so it was in the
center, that car maybe could have kept its brake wheel in place, as is the case
on the flat furthest from the camera. Note there is a removed
brakewheel mounted to the deck of the flat closest to the camera, and
another removed brakewheel mounted on the deck of the flat furthest from the
camera - presumably this last one came off the midle flat car
Any thoughts on this?
Claus Schlund
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Lloyd Keyser
Why is there not a Do No Hump sign on this load Lloyd Keyser
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Lloyd's question raises another question. When was the first hump yard built and where? Chuck Peck
On Sat, Dec 21, 2019 at 11:45 AM Lloyd Keyser <lloydkeyser@...> wrote:
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https://en.wikipedia.org/wiki/Classification_yard#Hump_yard
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"According to the PRRT&HS PRR Chronology, the first hump yard in the United States was opened May 11, 1903 as part of the Altoona Yards at Bells Mills (East Altoona). Other sources report the PRR yard at Youngwood, PA which opened in the 1880s to serve the Connellsville coke fields as the first U.S. hump yard." Only as far away as Google and Wikipedia. ;o) Bill Lugg
On 12/21/19 9:56 AM, Charles Peck wrote:
Lloyd's question raises another question. When was the first hump yard
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mel perry
out of curiousity, why weren't these comments/questions not included, in the OP?, where they belonged, instead of creating a seperate thtead? mel perry
On Sat, Dec 21, 2019, 9:13 AM Bill Lugg <luggw1@...> wrote: https://en.wikipedia.org/wiki/Classification_yard#Hump_yard
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Lloyd Keyser
Sorry, I just did not think of it. Lloyd Keyser
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Drew Bunn
Not to sound insulting, Claus - but I think you're seeing things. There is no way that load would remain upright unless it was perfectly centered on those flats. I've unloaded centerbeams, and two forklift operators have to remove the load evenly on both sides or the car will fall over. Cheers
On Sat., Dec. 21, 2019, 10:21 Claus Schlund \(HGM\), <claus@...> wrote:
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Bill Keene
OK. Here is my take on why the girder was not mounted to pivot on the longitudinal center of the end flat cars…
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Placing the pivot point closer to the truck would result in less overhang inward on curves. Also doing so may reduce the outward overhang at the ends of the girder. In short, there may have been operational restrictive reasons for what appears to perhaps be an odd loading. Also, a long shot idea here, loading closer to the trucks would perhaps allow for a heavier load to be carried than what would be the limit if loaded at the longitudinal center of the car. Both of the above are just food for thought. Cheers, Bill Keene Irvine, CA
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Claus Schlund \(HGM\)
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Hi Drew,
No insult taken, but perhaps I was unclear in my
question...
I meant to say it was not centered across THE LONG
WAY. Indeed, I feel as you do, that it is properly centered across the
short way
On the flat car closest to the camera, the load
comes to nearly the end sill of the car. On the flat car furthest from the
camera, the load comes to only about the middle of the car. If centered the long
way, both flats would have the load end at roughly the same place
on both cars.
Claus Schlund
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Claus Schlund \(HGM\)
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Hi Bil and List Members,
Interesting insights there Bill!
From the flat car's point of view, this would
appear like it is a point load, since the flat carries the full load at
the spot where the load bolsters (is there a more correct term for this?)
are installed on the flat. Puting the point load right in the middle of the car
would make the load stress the worst it could possibly be, and moving it closer
to the trucks would help with this.
Claus Schlund
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Drew,
He meant end to end, not side to side 😉 and the load is definitely offset to the near end of each of the end cars. That is for good reason. The location of this load is due to several factors:
1) Most flat cars CANNOT carry their rated load concentrated at the center of their span. Offsetting the load to one end or the other allows a heavier load to be carried. In the PRR fleet, the F22 and F23 were among the only cars that could carry their rated
weight in the center of the span of the car.
2) There were limits for the allowed free span between the pivot points. Too long a span would overhang on curves and could exceed line side clearances. Think about 85' passenger cars on 18" HO scale radii 😉
3) There were also limits for the free end length for the same reasons as #2, although that was less likely to be an issue
Removal of the brake wheel was no big deal... done all the time.
While hump yards were at least 25 years old at the time, they were not common. Looking at this load, I see a card on the side of the 3rd flat. While this is most likely a route card, it may also contain the instructions "Do Not Hump". Alternatively, rules are
made because of stupid people. At this point in time, that rule may yet to be in effect as everyone looks at this load and KNOWS it should not go over the hump. Give stupid folks a few more years to screw it up and the sign will be required.
Regards,
Bruce Smith
Auburn, AL
From: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io> on behalf of Drew Bunn <drew.r.bunn@...>
Sent: Saturday, December 21, 2019 12:24 PM To: main@realstmfc.groups.io <main@realstmfc.groups.io> Subject: Re: [RealSTMFC] Bridge girder on three PRR FM flat cars Not to sound insulting, Claus - but I think you're seeing things. There is no way that load would remain upright unless it was perfectly centered on those flats. I've unloaded centerbeams, and two forklift operators have to remove the load evenly on both
sides or the car will fall over.
Cheers
On Sat., Dec. 21, 2019, 10:21 Claus Schlund \(HGM\), <claus@...> wrote:
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I think he was referring to the fact that the load is all the way left on the nearest car, and not centered on the center car.
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Thanks! Brian Ehni (Sent from my iPhone)
On Dec 21, 2019, at 12:24 PM, Drew Bunn <drew.r.bunn@...> wrote:
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Tony Thompson
Not that the load rests on both end flat cars between 4 and 5 stake pockets from the end. As Bruce Smith mentioned, this is doubtless the preferred loading point. Tony Thompson
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Charlie Vlk
Llyod
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Think about the dynamics of the three cars going over the approach and crest of the hump.....the load is not secured for extreme vertical curves nor the impact of running into a string of cars after being humped (if the middle car didn’t dislodge the girder as it went over the top!!). Charlie Vlk
On Dec 21, 2019, at 10:57 AM, Charles Peck <lnnrr152@...> wrote:
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mel perry
that also my thought, there is no forward or backwards restrains at all, i guess back then "g's" hadn't been invented, lol :-) mel perry
On Sat, Dec 21, 2019, 12:32 PM Charlie Vlk <cvlk@...> wrote:
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Matthew Metoyer
These Erie photos tend to be of damages, either to the car or lading. Could the load have shifted and hence the photo? Matthew Metoyer
On Sat, Dec 21, 2019 at 3:01 PM mel perry <clipper841@...> wrote:
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Guy Wilber
mel perry wrote:
“that also my thought, there is no forward or backwards restrains at all, i guess back then "g's" hadn't been invented, lol” The load matches The ARA’s Open Top diagram (for the period) for girders. The manufactured bolsters are bolted to the flat car deck through its ends and on each side of the center sill. The girder is secured on each end with the rods passing through the attached bolster and into the bracket bolted to the bottom flange. Guy Wilber Reno, Nevada
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mel perry
if you look closely at the pic, the front centering bracket is partially separated from the bottom of the girder, indicating that the load had shifted forward slightly probably becauae of lack thereof or insufficient restraints, wonder if cfr49 was in existence back then or would have been the aar? mel perry
On Sat, Dec 21, 2019, 3:23 PM Matthew Metoyer <mmetoyer@...> wrote:
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Bud Brock
Also note the watermelon car. The 2 doors are strapped together to move as one.
Bud Brock
PC&C RR
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