Commonly used are R-type rivets, fan rivets, blind rivets (core rivets), tree rivets, semi-circular heads, flat heads, semi-tubular rivets, solid rivets, countersunk rivets, blind rivets, hollow rivets, which are usually used The self-deformation connection is riveted. Cold rivets, generally less than 8 mm, are hot rivets larger than this size. However, there are exceptions. For example, the nameplate on some locks is riveted by the rivet and the interference of the lock hole.