If we want to loosen the rusty screw, we can drop a few drops of kerosene around the screw mouth, wait a while, let the kerosene penetrate, and it will be easy to come down.

If the purpose is to remove the rust on the screw, there is no good simple method. The rust at the bottom can be removed by pickling, and then corrosion inhibition treatment can make it rust-free for a short time, but not for a long time.

If it doesn't rust for a long time after rust removal, it will only be sent to the electroplating factory for galvanizing, and the galvanized screws can not rust for many years.