Trailer on Flat Cars

[Anonymous]

QUOTE: Originally posted by dharmon

What you probably saw was a TTEX 2-Unit ''Long-Runner'' Trailer-Only Car. It's two cars treated as a unit, with a drawbar between them.
(I can't seem to be able to post the direct link but its at

http://www.ttx.com/

Go to Equipment Overview
Then Cars
and down to TTEX

It's a good site for general info.

Yep- that's exactly what I saw. The only trailer on the unit was the one I mentioned. Do they place it over the drawbar for weight on the couplers or is that just where it goes based on its size? Thanks for the link and info.

[DTomajko]

Chains or straps are no longer used to secure trailers on flatcars anymore. The only things that secure a trailer are the hitch the trailer kingpin couples to,(similar in design and function to a tractor 5th-wheel), and the rubrails on the car deck. The rubrails prevent the trailer tires from sliding sideways off the deck. Also, the design of trailer air brakes applies the brakes even when there is no air or truck attached. If the trailer wheels are moving, there is a problem with the brake system. What you may be seeing is a sliding of the tires or the rocking of the suspension. Good luck and stay safe.

[dharmon]

What you probably saw was a TTEX 2-Unit ''Long-Runner'' Trailer-Only Car. It's two cars treated as a unit, with a drawbar between them.
(I can't seem to be able to post the direct link but its at

http://www.ttx.com/

Go to Equipment Overview
Then Cars
and down to TTEX

It's a good site for general info.

[Overmod]

By definition yes; it's a kingpin-in-fifth-wheel arrangement.

Even though the trailer bogie is secured by chains or straps, it can roll or move just a little fore-and-aft to accommodate the slightly different length and direction as the trailer nose attach point moves relative to the trailer centerline on curves.

[Anonymous]

This last weekend at Porter Junction I saw a trailer on a flat car with it's tongue on the following flat car- is the tongue on some sort of a pivot to negotiate curves?