NS hopper question

[nitroboy]

While watching the Norfolk Southern main line traffic yesterday with my daughter, I noticed what looks like a very big chunk of rubber in the middle truck spring. It protruded out about a foot also. Now, some of the trucks had them, and some didn't. And these hoppers were older ones, some of the "NEW" date on them were from '77. Does anyone know what these are, or why they are in there?

[88gta350]

I've seen a lot of NS hoppers and have never noticed that. I'd be interested in knowing what it was as well. I'll have to keep a closer eye out next time!

[oltmannd]

I think what you were looking at was likely a hydraulic damper (shock absorber). It's to keep the cars from hamonic rocking at low speeds on jointed rail.

[Overmod]

Don, might also be elastomer block -- same sort of effect as hydraulics except that internal friction in the elastomer does the same job as the dashpot or valving. I believe I have seen several trucks that had elastomer actually replacing some of the springs in the nests -- one thing this would get rid of would be the need to 'tune' the different sizes of spring to eliminate surging at critical speeds or loads.

Might also (he said cynically) be something proprietary to get around patent or royalty issues.

[nitroboy]

Thanks for the info guys!!!

[choochin3]

I heard of someone calling it a snubber.