Empire Belt RR ALcos

Empire Belt RR ALcos
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Tuesday, July 28, 2015

Pullman Standard Hydro Frame 60 Boxcar

Hello Everyone,

Just back from vacation and thought I'd post this blog entry while I continue my research for the NYC-PRR Throw Down Series. I recently acquired a few boxcars from fellow modeler Bobby G. who I know from TrainLife.com. Bobby is moving to O scale and disposing of the last of his HO rolling stock. One the cars I purchased from Bobby was an Atheran BB 50' Kansas City Southern ribbed side boxcar with the words
PS HYDRO FRAME 60 keeps loads SAFE from SHOCK in big letters.

PS Hydro Frame 60? Interesting. I checked my box car fleet and discovered an Athearn BB New Haven 50' boxcar also had this lettering but in a circle. So what was this Hydro Frame 60 from Pullman Standard?

Hydro-pneumatic cushion gear for railway car
US 3917075 A

In a railway car underframe center sill structure, an end-of-car cushion unit of the hydro pneumatic type for absorption of buff forces and located in the cushion pocket at the end of the center sill and coupled with the yoke and coupler arrangement. The cushion unit has a moveable hydraulic fluid containing cylinder connecting with the yoke and coupler arrangement and fixed piston having its inner piston rod end connected in the center sill and its outer piston head orificed within the cylinder to receive reciprocably a central metering pin fixed in the cylinder for transfer of hydraulic fluid to either side of the piston head and in and out of draft chamber portions of the cylinder. A moveable gas piston is in the inner end of the fixed piston and has gas under pressure on the piston inner end, the piston outer side being in hydraulic fluid communication with the orifice. The gas piston has a rolling seal connection and stop within the fixed piston. A rolling seal in the form of a boot connects the cylinder and piston and acts as a dust protector for the piston rod. An alternate form of gas piston slidingly floats in the hydropneumatic chamber in the fixed piston. The cushion arrangement is also provided with buff cylinder stops that hit the striker and provided with recessed draft cylinder stops near the outer end of the cylinder.

For much more on this check this link: https://www.google.com/patents/US3917075

From the Virginia Museum of Transportation
  • Manufacturer: Pullman Standard
  • 100 produced for the Richmond Fredericksburg & Potomac in 1963. The RF&P ran exclusively in Virginia and was partially owned by the Commonwealth of Virginia Retirement System.
  • Equipped with the Pullman Standard Hydro frame-cushioning device, this spring loaded coupler softened the impact when cars were switched. The device added approximately 10 ft to the length of the car.

# 2305

  • Built in 1963
  • Served the RF&P for 24 years
  • Retired May 1987
  • Donated to the Museum by the Richmond, Fredericksburg & Potomac Railroad in February, 1988

RF&P Boxcar

Kansas City Southern 1365 proudly display it's PS HYDRO FRAME advertisement. Checking the RF&P car above note the extension of the coupler box on the end of the car. 

KCS 1365 coupled up to a 40' NH boxcar (also from Bobby G).

Cleaned up but standard under frame on the car. Now to see if I can find a way to make this an actual PS Hyrdo Frame 60 boxcar. And yet another modeling project is born! 

 A quick search reveals that Details West offers a cushioned coupler box that might work quite nicely for extending the coupler pockets on this car. They also offer a hydra frame  that might work as well.


  1. Nice couple of cars John! I didn't know anything ab out the cushioned couplers or hydro frames. Looks like an interesting project for the KCS boxcar. Have to admit that before coffee that long paragraph describing the Hydro-pneumatic cushion gear for railway car US 3917075 A had my eyes crossing while I vocalized "Whaaat?" I get it though...less impact shock during coupling. I think I have an old Santa Fe boxcar with something like Shock Control printed on the side. Cool stuff!

    1. Thanks Ralph! That patent info is a tough read with coffee. My eyes glazed over every time I tried to read and sum it up. A copy and paste was the way to go. Could be an interesting project though for the cars that advertise this type of cushioning device.

  2. The fleet is growing in leaps and bounds! Freight car acquisitions looks good. Nice recap of the PS Hydro Frames

  3. Thank You 1 to 1 scale Sir Neal!