Originally Posted by PDXrafter
...To whoever said they doubt my ability to restore the trailer. Why do you post stuff like that? You don't know anything about my abilities, you only know that I don't specialize in trailer axles.
I understood his point... if you don't know what kind of axle the trailer has, I too am skeptical of your ability to DIY repairs. It simply implies inexperience and we don't need any more questionably built hunks of metal hurtling down our highways. Maybe your a hell of a welder, but you came onto a forum and asked a group of pretty basic questions so my guess is not likely. Nothing personal meant, I'm sure.
As far as the original question goes, it also looks fairly rusty... you might think about poking around some of those rust spots and see how bad they are. If it's just surface flaking you may be ok, but if it's rusting from the inside out it might turn into a death trap for some other motorist.
On the axle discussion - I'm guessing this is roughly what you have...
It's an offset axle meant to be used with leaf springs mounted directly to the frame. Probably for some sort of non-highway use or by someone that shouldn't have been DIY'ing shit.
At first glance a torsion axle might look similar but the arms would move when weight is applied (plus other less obvious details). They do make torsion axles in all kinds of configurations, but if that is actually one on that trailer, It would likely be upside down.