The meaning of Welding tattoo is firm and non separation. Before the end of the 19th century, the only welding process was metal forging welding, which was used by blacksmiths for hundreds of years. The earliest modern welding technology appeared at the end of the 19th century, first arc welding and oxygen gas welding, and then resistance welding.
The history of metal connection can be traced back to thousands of years ago. The early welding technology was found in Europe and the Middle East in the bronze age and iron age. Thousands of years ago, the Babylonian civilization in Cuba began to use soldering technology. In 340 BC, welding technology was adopted when the ancient Indian Delhi iron column weighing 5.4 tons was manufactured.
Source: @josephgutshall