Causes of Burrs in Medium-Frequency Inverter Spot Welding？

Burrs, also known as projections or flash, are unwanted raised edges or excess material that can occur during the spot welding process using medium-frequency inverter spot welding machines. They can compromise the quality and aesthetics of the weld joint. This article aims to explore the reasons behind the formation of burrs in medium-frequency inverter spot welding.

1. Excessive Welding Current: One of the primary causes of burrs is excessive welding current. When the welding current is too high, it can lead to excessive melting and expulsion of molten metal. This expulsion creates protrusions or burrs along the weld seam, resulting in an uneven and imperfect joint.
2. Inadequate Electrode Pressure: Insufficient electrode pressure can contribute to the formation of burrs. The electrode pressure is responsible for maintaining proper contact between the workpieces during the welding process. If the electrode pressure is too low, it may not effectively contain the molten metal, allowing it to escape and form burrs along the edges of the weld.
3. Improper Electrode Alignment: Incorrect electrode alignment can cause localized heat concentration and, consequently, the formation of burrs. When the electrodes are misaligned, the heat distribution becomes uneven, leading to localized areas of excessive melting and material expulsion. These areas are prone to burr formation.
4. Excessive Welding Time: Prolonged welding time can also contribute to the generation of burrs. When the welding time is excessively long, the molten metal may flow beyond the intended boundaries, resulting in the formation of unwanted projections. It is essential to optimize the welding time to prevent excessive melting and burr formation.
5. Poor Workpiece Fit-up: Inadequate fit-up between the workpieces can lead to burr formation during spot welding. If the workpieces are misaligned or have gaps between them, molten metal can escape through these openings, resulting in the formation of burrs. Proper alignment and fit-up of the workpieces are necessary to prevent this issue.

Understanding the factors that contribute to the formation of burrs in medium-frequency inverter spot welding is crucial for achieving high-quality weld joints. By addressing issues such as excessive welding current, inadequate electrode pressure, improper electrode alignment, excessive welding time, and poor workpiece fit-up, manufacturers can minimize the occurrence of burrs and ensure clean and precise welds. Implementing appropriate welding parameters, maintaining optimal electrode pressure, ensuring proper alignment and fit-up of workpieces, and optimizing welding time are essential steps in preventing burr formation and achieving aesthetically pleasing and structurally sound weld joints.