9781422273340

CHAPTER 1

THE WORLD OF WELDING WELDING: YESTERDAY AND TODAY Welding is the process of using high heat, and often a filler metal, to join two or more pieces of metal or to fill gaps in metal parts. Welders may also connect thermoplastic pipe and other materials. Some welding methods use pressure to help join the two pieces together, while others use pressure and high heat, or just high heat. The two metals that are being welded must be similar in chemical makeup. When the weld is completed and the metals cool, a joint has been created that is as strong or stronger than the base metal. There aremany types of welding processes. Welding plays an important role in construction, manufacturing, and other industries. It is used in approximately 50 percent of the industrial and commercial products that make up the gross domestic product (GDP) of the United States, according to the American Welding Society (AWS). The technical process of welding may seem modern, but archaeologists have found evidence of welding all the way back to the Bronze Age , when

The World of Welding

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