Around 1920, electric arc welding technology was widely used, the processing of safes, also soon used this new technology, the safe industry into a whole new era.

The history of the safe, with the development of locks. 8th century, the East Romans made the original blade lock, In the early 18th century, the British Denis Kevan will lock the metal blade using spring control rotation, the key inserted into the lock must first turn the blade to contact the latch notch to open. 19th century, European manufacturers invented a senior cam turn piece lock, the key teeth increased to 1600 kinds, and later a variety of improvements to make The key tooth pattern increased to tens of thousands of variations.

In the mid-18th century, most of the American lock industry was a copy of European products, with the American contribution being the widely used poppet lock, which was made by American Nirus Yale and his son Nirus Jr. Yale and his son, Linus Yale, Jr. Linus Yale, Jr. invented in the nineteenth century, the sling lock and the leaf lock were widely used at the beginning of the development of safes, they were widely used, while leaf locks have been used since then through continuous development. The lock-making industry and the safe product industry are mutually reinforcing and complementary.