Essential for Factory Automation: Four Advantages of Resistance Brazing

Resistance Brazing is a welding method that utilizes the resistance heat generated by the passage of an electric current through the workpieces and their contact points. It requires no filler metal, offers high production efficiency, minimizes weld deformation, and is easily automated. The main principle of resistance welding is that the resistance heat generated by the current flowing through the contact surfaces and adjacent areas of the workpieces heats the workpieces to a molten or plastic state, thereby achieving a metallic bond.

Spot welding: The workpieces are assembled into an overlapping joint and pressed between two cylindrical electrodes. Resistance heat melts the parent metal, forming a weld spot. This method is primarily used for welding thin sheets.

Seam welding: A rotating, disc-shaped roller electrode replaces the cylindrical electrode. The workpieces are assembled into an overlapping or butt joint and placed between two roller electrodes. The roller presses the workpieces while rotating, applying current continuously or intermittently to form a continuous weld seam. This method is primarily used for welding structures with relatively regular weld seams that require a tight seal.

Butt welding: The workpieces are welded together along the entire contact surface. This method includes resistance butt welding and flash butt welding. Resistance butt welding is primarily used for welds with simple cross-sections, diameters, or sides less than 20 mm, and low-strength welds. Flash butt welding is often used for critical welds and can weld both homogeneous and dissimilar metals.

Projection welding: It is a variation of spot welding, in which a prefabricated raised spot is placed on one workpiece. During projection welding, one or more nuggets are formed at the joint.

When the nugget is formed during Resistance Welding, it is always surrounded by a plastic ring, isolating the molten metal from the atmosphere and simplifying the metallurgical process. The heating time is short, and the heat is concentrated, resulting in a small heat-affected zone, minimal deformation and stress, and generally no post-weld correction or heat treatment steps are required.

Compared with processes like Furnace Brazing, Resistance Welding requires no filler metals, such as wire and electrodes, or welding materials such as oxygen, acetylene, and hydrogen, resulting in low welding costs. The operation is simple, easily mechanized, and automated, improving working conditions. The weld is highly productive, noise-free, and odor-free. In large-scale production, it can be integrated into the assembly line with other manufacturing processes.

As welded and Brazed Joints continue to advance, we should also pay attention to a closely related technology: Butt Welding, which uses the resistance heat generated by an electric current passing through the workpiece and the brazing filler metal to melt the brazing filler metal and fill the gap between the joints, thereby achieving metal connections.

Compared to resistance welding, it offers unique advantages in certain applications. For example, it can achieve connections at lower temperatures, minimizing thermal impact on the parent metal, making it suitable for welding heat-sensitive materials. Furthermore, it can also connect dissimilar metals, expanding the scope of welding applications. In the manufacturing of high-precision, high-performance components, Resistance Brazing provides more reliable connections and meets higher quality requirements.