Sew welding is a widely used resistance welding process, mainly used for continuously welding the joints between two metal workpieces to achieve the purpose of sealing or structural connection. In actual production, welding speed is one of the important factors affecting the quality, efficiency, and cost of sew welding. Therefore, how to reasonably control the welding speed of sew welding has become a key technical issue in welding technology.



One, The Influence of Welding Speed on Seam Weld Quality



The speed of welding directly affects the size of the heat input. Too fast a speed can lead to insufficient heat input, insufficient melting of the weld, and the appearance of defects such as incomplete welding, slag, and pores; while too slow a speed can cause metal overheating, leading to burn-through, deformation, or tissue deterioration, affecting the mechanical properties and sealing properties of the joint. Therefore, an appropriate welding speed can ensure good overlap between weld points and improve the overall quality of the weld.



Two, Factors Affecting Welding Speed



1. Material Properties: Different materials have different thermal conductivity, melting points, and plastic deformation capabilities, so the welding speed needs to be adjusted accordingly. For example, aluminum alloys have good thermal conductivity, and faster speeds should be used during welding to prevent excessive heat loss; while high-carbon steel may require slower speeds to ensure complete melting.



2. Plate Thickness and Lap Width: The thicker the plate, the greater the required welding heat, and the welding speed should be appropriately reduced; the lap width also affects the welding effect, and adjustments should be made according to specific conditions.



3. Electrode Pressure and Current Parameters: In resistance welding, the current and electrode pressure determine the amount of heat input and the ability of plastic deformation. Under the condition of constant current, increasing the electrode pressure may be required to ensure the compressive effect of the weld point when the welding speed is increased.



4. Equipment Performance: The power of the welding equipment, the accuracy of the control system, and the degree of automation will affect the adjustable range and stability of the welding speed.



Three, Methods for Controlling Welding Speed



1. Setting Reasonable Process Parameters: Through welding process evaluation, the optimal range of welding speed is determined, and comprehensive optimization is carried out in combination with welding current and electrode pressure.



2. Adopting Automatic Control Systems: Modern seam welding equipment mostly uses PLC or CNC control systems, which can accurately control the welding travel and speed, thus ensuring the stability and repeatability of the welding process.



3. Real-time Monitoring and Feedback Adjustment: Using sensors and online monitoring systems, changes in the quality of the weld during the welding process are detected in a timely manner, and the welding speed is automatically adjusted according to the feedback information to achieve closed-loop control.



4. Operator Training and Standardized Operation: For manual or semi-automatic seam welding equipment, the experience and standardized operation of the operators are crucial for mastering the welding speed, and skill training and standardized operation management should be strengthened.



Four, Conclusion



In summary, welding speed, as one of the key parameters in the seam welding process, directly affects the quality of welding and production efficiency. In practical applications, welding speed should be scientifically and reasonably controlled according to material properties, product structure, equipment capabilities, and process requirements, and combined with advanced control technologies and management methods to continuously improve the level of welding technology. Only in this way can production efficiency be further improved, manufacturing costs reduced, and the market competitiveness of the enterprise enhanced, while ensuring product quality.