Hi Ray,
Looked at your pics........studied 'em well....and I've arrived at the conclusion that........well,it's.......then again........yup...that's what it is, and yessir, that's what it does!
First guess, an underpowered section car, with some extra junk layed on it.
Second guess, the shroud at the "back end" could hide a saw blade, so possibly it was used to cut the ties, in the middle, so they could be pulled out from either side.
Third guess, well, yours is as good as mine..
(and a smilie here that represents shrugging shoulders)
Pete