The lock core has a shoulder strap that can be fixed, also called marbles. There are springs on marble, which are usually sealed with lead or tin. To fold the lock core, you must first pry open which lead or tin seal is fastened on the lock core, then take out the spring and pour out which shoulder strap, and then you can remove the lock core. If the pin of the key is not removed, neither can the lock core. At this time, which part of the key should you remove together according to the above method? Generally, there are 4-5 groups.