New preloader, worked about 17 days so some info may be missing or slightly off. Also, this is how it is at my center, your center may differ:
Unloader. Not much info I can give you here, as I haven't worked it or seen it done.
Loader. You put the boxes in the cars. You mentioned this.
Sorter. There are two systems (from what I know); a belt system (unfamiliar with this) and a cage system (what my center has). The cage system at my center has two systems with four colors of cages with three rows. Sorters get the majority of the packages from the belt (aside from most smalls and bulk. Smalls come down the slide in bags for the most part and an occasional bulk piece slides by. Do not sort these, send these to the clerk). You put the box in the corresponding cage.
Clerk. You probably won't work this. From what I hear, UPS is trying to phase these out. My center has one.
Bulk (could be part of unloading). Again, don't know much about this aside from the fact that large packages are loaded onto carts and driven onto package carts. These packages weigh from 70lbs to 150lbs OR are very large or oddly shaped.
Small sort. Also called tilt tray. Essentially, you take small packages (generally 9lbs or less, smaller than the tray. 60 percent or so are envelopes) and place them HIN up for a machine to be scanned. There are others who place packages in bags; however, I have not seen this work done and thus cannot comment.
I apologize for any wrong or missing information. There are probably other aspects to the preload; however, as you are new, I can't imagine you doing anything else.
