Screen printing can be done very easily on flat objects. If the lettering you wish to put on a cylindrical object is small enough, you can probably get it to work, but it won't be easy. The expensive machines are capable of doing it well and doing a lot of items in a short period of time. Best thing to do is make a screen and try it.

It's been years since I did any screeing, so don't ask me any questions about current technology. Maybe someone else here will chime in.......