These are wire rope pulley sheaves from a 500 ton crane.  The sheaves are 33" in diameter, 5.25" wide.  The bronze bearing is 4.25".  These can be used for table bases, lamp bases or just about anything.  What ever you plan to build.  Any tall sculpture can use the 4" pipe to work as a base.  

All you steampunk builders, these are Superheated steam, we are talking 700°F steampunk.