SMA: Shield Metal Arc Welding (SMAW)
SMAW is the most widely used welding process for metal fabrication because of its low cost, flexibility, portability, and versatility. The welding machine itself can be as simple as a 110-volt, step-down transformer that can be plugged into a normal electrical outlet. The electrodes are available from a large number of manufacturers in packages ranging from 1 lb (0.5 kg) to 50 lb (22 kg).
The SMAW process is very versatile because the same SMA welding machine can be used to make a wide variety of weld joint designs in a wide variety of metal types and thicknesses, and in all positions:
• Joint designs—In addition to the standard butt, lap, tee, and outside corner joints, at SMAW has been certified to be used to weld every possible joint design.
• Metal types—Although mild steel is the most common SMA-welded metal; stainless steel, aluminum, and cast iron are easily SMA welded.
• Metal thickness—Metal as thin as 16 gauge and approximately 1/16 in. (2 mm) thick up to several feet thick can be SMA welded.
SMAW is a very portable process because it is easy to move the equipment, and engine-driven generator-type welders are available. Also, the limited amount of equipment required for the process makes moving easy.
The process is versatile, and it is used to weld almost any metal or alloy, including cast iron, aluminum, stainless steel, and nickel.