Name that cyrogenic tank car thingamajig

[sirenwerks]

Found some pics of modest-sized Industrial Air Products six-axle cyrogenic tank cars that were built in the late 60s and called out of Portland OR, so they caught my eye as something I'd like to model. All of the five cars in the series have some sort of bird cage box underneath. At first I thought it was for hosing required to offload the car, but when I found this close up, I became perplexed. And, as usual, these things keep me up at night so I could use help identifying what is in there. My educated guess mechanism is grasping at straws - Radiator tube sets? Removable safety handrails? An old cast iron bed frame? It's a great place to hitch a ride and, because the cage is not secured, I presume whatever is in it is not that valuable...

[muktown128]

I believe these are the heat exchangers.  I wouldn't suggest staying there if trying to hitch a ride.

[C855B]

I believe these are the heat exchangers.  I wouldn't suggest staying there if trying to hitch a ride.

Yes. The cage serves as both protection from objects being thrown into them, and protection for personal accidentally bumping into them.