Laser Modernization: Advancing Existing MIG/MAG and TIG Welding Systems Without Robot Replacement

As industrial automation grows, robots are increasingly used in both simple handling and advanced manufacturing processes. Welding remains one of the most common robotic applications, typically performed using MIG/MAG, TIG, or hybrid technologies. Although established and widely adopted, these methods impose inherent limitations in welding speed, heat input, fixture requirements, and overall process stability.

Limitations of MIG/MAG and TIG Welding

MIG/MAG welding can reach speeds of up to 3 m/min on thin metals, yet it generates a wide heat-affected zone (HAZ), increasing the likelihood of thermal distortion. This requires rigid and costly fixtures to maintain part geometry. In addition, MIG/MAG produces significant metal spatter, which contaminates torches, sensors, and cables, and often demands manual post-processing such as grinding.

TIG welding, while valued for its precision and aesthetic seam quality, operates at much slower speeds - up to 0.6 m/min - and still produces a considerable HAZ. TIG applications also depend heavily on expensive tooling to control distortion.

Laser Welding as the Third Option

Robotic laser welding combines the high speed of MIG/MAG with the precision and cleanliness of TIG. Despite its advantages, adoption is often constrained by the requirement to purchase an entirely new robotic system, significantly increasing investment costs.

Diodela Retrofit: Laser Welding Using Your Existing Robot

To address this challenge, Diodela developed a retrofit solution that transforms existing MIG/MAG or TIG robotic cells into laser welding cells by replacing the original torch with a dedicated laser welding torch. This approach preserves the robot—typically the most expensive component—while substantially enhancing welding performance.

Laser welding can reach speeds of up to 12 m/min on thin metal alloys. Due to its high travel speed, the heat-affected zone is dramatically reduced, nearly eliminating distortion and minimizing fixture requirements. In many cases, standard clamps are sufficient. The process ensures stable parameters, minimal spatter, and a clean seam profile that often requires no additional finishing.

Retrofit Installation Process

Retrofitting begins with the removal of the existing welding torch and installation of Diodela’s two-axis laser welding torch. The laser source is then connected to the robot controller, using Ethernet TCP/IP for newer robots or Digital I/O for older systems. After mechanical and electrical integration, the robot and laser source are paired to work synchronously.

Diodela engineers train the operators and, if necessary, adjust the laser parameters to the customer’s specific products. The entire conversion typically takes up to two days, allowing production to resume quickly with minimal downtime.

System Architecture and Technical Characteristics

At the core of the retrofit solution is a Diodela CW single-mode laser source available from 1 kW to 6 kW, enabling weld depths from 0.5 mm to 15 mm. The robotic laser torch incorporates a two-axis scanning mirror that simplifies programming, a laser insulator allowing welding at any angle, and an integrated CCD camera for live process monitoring.

Depending on application requirements, the system can include an air-knife module to protect torch components from contaminants such as spatter and smoke. Both the laser and the torch are water-cooled, ensuring reliable 24/7 continuous operation. Communication between the robot controller and the laser PLC is established through Ethernet TCP/IP or Digital I/O, with full integration into the robot’s safety logic.

For applications requiring enhanced accuracy or verification, an optional seam-tracking sensor enables automatic correction for seam deviations and supports post-weld quality inspection.

Testing and Support

Clients can evaluate Diodela’s, robotic, or manual laser systems in the company’s laboratory. Diodela engineers provide process optimization support and help identify suitable laser parameters for a broad range of welding applications.

If you would like to determine whether your existing MIG/MAG or TIG robotic system is suitable for laser retrofit, contact Diodela. Their engineering team will assess your current setup and prepare a clear, application-specific upgrade plan to improve production performance.