Common Welding Processes Employing Constant Current Power Sources- A Comprehensive Overview

Which welding processes normally use a constant current power source?

Welding is a critical process in various industries, from construction to automotive and aerospace. The choice of welding process can significantly impact the quality and efficiency of the final product. One of the key factors in selecting a welding process is the power source used. Among the various types of power sources available, constant current power sources are commonly used in several welding processes. This article will explore the welding processes that typically utilize a constant current power source.

1. Shielded Metal Arc Welding (SMAW)

Shielded Metal Arc Welding, also known as stick welding, is one of the most common welding processes. It involves the use of a consumable electrode coated with flux, which generates an arc between the electrode and the base metal. The constant current power source is ideal for SMAW because it provides a stable arc and allows for better control of the heat input. This makes it suitable for a wide range of materials, including carbon steel, stainless steel, and aluminum.

2. Gas Tungsten Arc Welding (GTAW)

Gas Tungsten Arc Welding, also known as TIG welding, is a precision welding process that is often used for thin materials and high-quality welds. In GTAW, a non-consumable tungsten electrode is used to create an arc, and an inert gas, such as argon or helium, is used to shield the weld area from atmospheric contamination. A constant current power source is preferred for GTAW because it allows for precise control of the arc length and heat input, which is crucial for achieving high-quality welds.

3. Submerged Arc Welding (SAW)

Submerged Arc Welding is a high-productivity welding process that is commonly used for thick sections and long welds. In SAW, the weld pool is covered with a layer of flux, which protects the weld from atmospheric contamination. A constant current power source is typically used in SAW because it provides a stable arc and ensures consistent heat input, which is essential for achieving high-quality welds in thick sections.

4. Flux-Cored Arc Welding (FCAW)

Flux-Cored Arc Welding is a semi-automatic or automatic welding process that is often used for outdoor and underwater welding applications. In FCAW, a continuously fed flux-cored wire is used to create the arc, and the flux protects the weld area from atmospheric contamination. A constant current power source is suitable for FCAW because it provides a stable arc and allows for better control of the heat input, which is crucial for achieving high-quality welds in challenging environments.

In conclusion, constant current power sources are commonly used in several welding processes, including SMAW, GTAW, SAW, and FCAW. These processes benefit from the stable arc and precise control of heat input that constant current power sources provide. By understanding the advantages and limitations of each welding process, welders can choose the most appropriate power source to achieve high-quality welds in their specific applications.