Manual metal arc welding (MMAW)
Arc electrode welding
Manual metal arc welding is a metal arc welding process (MMAW) in which an electrical arc burns between a sheathed rod electrode and the material. No shielding gas is used in manual metal arc welding. The sheathed melting electrode forms a shielding gas to protect the smelt and supplies additives to create the required seam. Manual metal arc welding can be used on nearly all materials suitable for welding, simply and efficiently. Shielding gas is not supplied but is created – depending on the requirement and material – when the electrode sheath melts. The procedure is also used in small and medium-sized businesses and when building ships, pipelines as well as steel constructions and bridges outdoors.
Simple and gas-free
In Manual metal arc welding the welder clamps a rod electrode into an electrode holder and places it on the weld. When the rod electrode and its sheath melt, gas and slag are created that shield the weld pool and the arc from the atmosphere and prevent oxidisation of the seam. The slag reduces the surface tension, binds contaminates and helps to ensure that the weld cools evenly. Once the seam has cooled down, the slag is removed mechanically. Manual metal arc welding is a sturdy, simple and safe welding process that does not require gas. Manual metal arc welding is not dependent on the weather and can even be used under water. A further benefit is that the manual metal arc welding devices are usually very compact and easy to transport making them suitable for various sites.
Rod electrodes can be used to join almost all weldable ferrous materials, nickel and nickel alloys. These include structural, boiler and pipe steels, and also cast steel, stainless steel and hard-facing steels. The most important application fields are steel constructions, pipeline construction work and industrialised buildings.