S669510-055 - Hobart SWX 150 High Basicity Submerged Arc Flux

Technical Overview of Hobart SWX 150 Flux

The Hobart SWX 150 is a high-basicity, agglomerated aluminate-basic flux specifically engineered for the most demanding submerged arc welding (SAW) applications. With a basicity index of approximately 3.0 (Boniszewski), this flux is designed to promote superior metallurgical purity and mechanical properties in the weld metal. It is particularly effective when paired with a wide range of solid and cored wires to weld high-strength, low-temperature, and creep-resistant steels.

One of the defining characteristics of SWX 150 is its ability to deliver excellent impact toughness at very low temperatures, making it a standard choice for industries where structural integrity is paramount, such as offshore fabrication and nuclear power generation. The flux formulation ensures very low levels of diffusible hydrogen (typically less than 5ml/100g), which is critical for preventing cold cracking in thick-section weldments. It supports both AC and DC current types, offering flexibility in process setup while maintaining a stable arc and good slag detachability.

In specialized applications like narrow gap welding, the SWX 150 excels due to its good grain size distribution and slag removal properties. It is also widely used for double-jointing of pipes and fabrication of heavy pressure vessels. The flux is chemically neutral, meaning it does not significantly alter the alloy composition of the wire, allowing for predictable mechanical results based on the wire selection.