Arc welding

Arc Welding

Arc welding is a process used to join metal to metal by using electricity to create enough heat to melt metal, and the melted metals, when cooled, result in a binding of the metals. It is a type of welding that uses a welding power supply to create an electric arc between an electrode and the base material to melt the metals at the welding point.

History

The history of arc welding dates back to the late 19th century. The first recorded arc welding process was developed by Nikolay Benardos and Stanisław Olszewski in 1881, known as "carbon arc welding." Later, in 1890, C. L. Coffin patented an arc welding process using a metal electrode, which laid the foundation for modern arc welding techniques.

Principles of Arc Welding

Arc welding works on the principle of an electric arc that is formed between an electrode and the workpiece. The arc produces intense heat, which melts the metal at the joint between the two workpieces. The molten metal cools and solidifies to form a strong joint.

Components

• Power Supply: Provides the necessary electrical energy to create the arc. It can be either AC or DC.
• Electrode: Conducts current and melts to form the weld. Electrodes can be consumable or non-consumable.
• Workpiece: The metal pieces that are being joined.
• Shielding Gas: Protects the weld area from atmospheric gases such as oxygen and nitrogen.

Types of Arc Welding

There are several types of arc welding processes, each with its own applications and advantages:

• Shielded Metal Arc Welding (SMAW): Also known as "stick welding," it uses a consumable electrode coated in flux.
• Gas Metal Arc Welding (GMAW): Commonly referred to as "MIG welding," it uses a continuous wire feed as an electrode and an inert gas for shielding.
• Gas Tungsten Arc Welding (GTAW): Also known as "TIG welding," it uses a non-consumable tungsten electrode and is known for its precision.
• Flux-Cored Arc Welding (FCAW): Similar to GMAW but uses a tubular wire filled with flux.
• Submerged Arc Welding (SAW): Uses a granular flux to shield the weld zone.

Applications

Arc welding is used in various industries, including construction, automotive, aerospace, and shipbuilding. It is suitable for welding a wide range of metals, including steel, stainless steel, aluminum, and copper alloys.

Safety Considerations

Arc welding poses several safety hazards, including:

• Electric Shock: Due to the use of high voltage.
• Radiation: UV and IR radiation can cause burns and eye damage.
• Fumes and Gases: Can be harmful if inhaled.
• Fire and Explosion: Due to the high temperatures and sparks.

Proper safety equipment, such as welding helmets, gloves, and protective clothing, is essential to minimize these risks.

Also see

• Welding
• Metalworking
• Electric arc
• Welding helmet
• Welding joint