Chapter 7 GTAW, GMAW, and FCAW Equipment and Supplies
Learning Objectives
After studying this chapter, you will be able to:
Gas metal arc welding (GMAW) is a welding process in which an arc is struck between a consumable metal electrode and the metal workpiece. The consumable electrode wire is fed to the welding gun from a large spool that can hold several hundred feet (meters) of wire. The consumable electrode is the filler metal. The weld area is protected by a shielding gas. This process is used in production, welding shops, and automobile body repair shops to make excellent welds almost continuously. The welding skills required for this process are not as great as those required for some manual welding processes. In shop terms, this process is also known as metal inert gas or MIG welding.
Flux cored arc welding (FCAW) is similar in most respects to the gas metal arc welding (GMAW) process. The difference is in the electrode wire used. GMAW uses a solid wire electrode, and FCAW uses a hollow-core wire electrode that contains flux and alloying materials. The flux core provides a gaseous shield around the arc. FCAW can also use a shielding gas provided through the gun, similar to the GMAW process.
The equipment and supplies used for each process will be explained in this chapter. Chapter 8 will cover gas tungsten arc welding techniques and principles, and Chapter 9 will cover gas metal arc welding and flux cored arc welding principles and techniques. Studying these chapters, coupled with actual welding practice, will build the skills and techniques you need to master these welding processes.
Learning Objectives
After studying this chapter, you will be able to:
- Identify and describe the function of each component of a GTAW, GMAW, and FCAW station.
- Name the various types of shielding gases used in GTAW, describe their characteristics, and evaluate their effectiveness.
- Name the various types of shielding gases used in GMAW and FCAW, describe their characteristics, and evaluate their effectiveness.
- Identify and specify the type of electrode used for GTAW, referring to the tables provided in the book and using the AWS electrode classification system.
- Identify and specify the various electrode wires used for GMAW and FCAW, using the tables provided in the book and the AWS electrode classification system.
Gas metal arc welding (GMAW) is a welding process in which an arc is struck between a consumable metal electrode and the metal workpiece. The consumable electrode wire is fed to the welding gun from a large spool that can hold several hundred feet (meters) of wire. The consumable electrode is the filler metal. The weld area is protected by a shielding gas. This process is used in production, welding shops, and automobile body repair shops to make excellent welds almost continuously. The welding skills required for this process are not as great as those required for some manual welding processes. In shop terms, this process is also known as metal inert gas or MIG welding.
Flux cored arc welding (FCAW) is similar in most respects to the gas metal arc welding (GMAW) process. The difference is in the electrode wire used. GMAW uses a solid wire electrode, and FCAW uses a hollow-core wire electrode that contains flux and alloying materials. The flux core provides a gaseous shield around the arc. FCAW can also use a shielding gas provided through the gun, similar to the GMAW process.
The equipment and supplies used for each process will be explained in this chapter. Chapter 8 will cover gas tungsten arc welding techniques and principles, and Chapter 9 will cover gas metal arc welding and flux cored arc welding principles and techniques. Studying these chapters, coupled with actual welding practice, will build the skills and techniques you need to master these welding processes.