If you are concerned with your black pipe rusting there are a couple of solutions available to you that are easy for you to do.
Since black pipe does not have any protective coating, if you want to keep it from rusting you have to do a couple of things. This becomes more important if your pipe is in an area of moisture and high humidity.
Keeping your black pipe from rusting is as easy as painting it. Locate the areas where you are concerned about rust forming on your black iron pipe. Once you have identified the area you will need to clean it. Clean the surface of any dirt, oils, rust, or flaking. You can use acetone mineral spirits. Make sure that the area you wish to paint is thoroughly clean because any oily surface will not allow the paint to adhere.
Now that your pipe is clean and ready for you to paint, spray with a light coat of rust inhibitor paint. Once this has dried you can then add the first layer of topcoat paint. Let this first layer of your topcoat thoroughly dry before adding a second coat.
Don’t forget any inside areas that need to be protected. Be also especially attentive to those hard-to-reach areas and any crevices that may be on your pipe.
Once this is done, you are good to go. Your pipe should no longer rust. However, you will still need to monitor your pipe periodically to make sure that all of your paint is still in place. If you find areas that don’t have the paint coat needed, you can repeat the process above in these areas.
There you have it. You now know what to do and how to go about doing it to keep your black pipe from rusting. Don’t want to go through all of this to keep your pipe from rusting? Then use a galvanized pipe that is made with steel and zinc to not allow rusting of the pipe.