The best way to ensure that your chrome rims will last for a long time, and not incur any damages is by regular and proper maintenance of them. One of the problems with rims, can that be a costly issue to deal with, is that once a chip happens in the rim–a chip that goes through the chrome plate and down to the metal, the only way to repair it is to remove the wheel entirely, sand it down and get it re-dipped in chrome.
This can be a bit costly, but is necessary when one wants that perfect shine of beautiful chrome rims. If the chip does not reach the metal however, there are a variety of buffing substances or creams that will serve to smooth out the smaller chips and scratches, sometimes they will remove these entirely, sometimes they will serve to make those less noticeable. It simply depends on just how severe the damage is.
Most auto stores will have products that will help with the removal of scratches, and most definitely either Pep Boys or Autozone will carry a variety. It is most wise to spend a little money on the cleaning products that you will use on the chrome surfaces of your rims. Saving a little bit and buying the cheaper cleaners will cause frustration as the smear and just do not work very well all around.
Once those smudges are there it is hard to remove them. Cleaning the rims should be done regularly as they are susceptible to the build up of oxidation. When this builds up on the chrome it could cause the tire to eventually separate from the rim, which is dangerous, as well as costly as if the rim separates it could fly off the tire as one is driving down the road, causing the need to replace the rim.